2023 UPDATE – Canadian Urological Association guideline: Management of cystic renal lesions

Question 1

In the 2023 update of the Canadian Urological Association guideline on the management of cystic renal lesions, how should patients with a renal cyst be classified?
A. Bosniak classification v2015
B. Bosniak classification v2019
C. Bosniak classification v2021
D. Bosniak classification v2023

Answer 1

B. Bosniak classification v2019

Explanation: According to the 2023 update of the Canadian Urological Association guideline, patients with a renal cyst should be classified as per the Bosniak classification v2019.

Question 2

What is the suggested strategy for Bosniak III or IV cyst measuring ≤2 cm, as per the 2023 Canadian Urological Association guideline update?
A. Immediate surgical intervention
B. Active surveillance
C. Radiotherapy
D. Chemotherapy

Answer 2

B. Active surveillance

Explanation: The 2023 update suggests that for Bosniak III or IV cyst measuring ≤2 cm, active surveillance is now the preferred strategy.

Question 3

As per the 2023 update of the Canadian Urological Association guideline, what are the suggested treatment options for Bosniak III or IV cyst measuring 2–4 cm?
A. Active surveillance or radiotherapy
B. Surgery or chemotherapy
C. Active surveillance or surgery
D. Radiotherapy or chemotherapy

Answer 3

C. Active surveillance or surgery

Explanation: The 2023 update of the Canadian Urological Association guideline suggests active surveillance or surgery as equal options for the treatment of Bosniak III or IV cyst measuring 2–4 cm.

Question 4

What has led to an increase in the number of individuals being diagnosed with renal cystic disease?

A) Increase in age of the general population
B) Increase in the use of abdominal imaging
C) Increase in smoking rates
D) Increase in high-protein diets

Answer 4

B. The use of abdominal imaging has increased, which has led to a rise in the diagnosis of renal cystic disease.

Question 5

What percentage of individuals over 60 years of age are estimated to be diagnosed with at least one simple renal cyst following abdominal imaging?

A) 10%
B) 25%
C) 33%
D) 50%

Answer 5

C. It is estimated that up to one-third (about 33%) of individuals over 60 years of age will be diagnosed with at least one simple renal cyst following abdominal imaging.

Question 6

What is the critical factor physicians need to consider when managing cystic renal lesions?

A) The age of the patient
B) The lifestyle of the patient
C) Distinguishing cystic lesions from solid renal masses with necrotic components
D) The cost of the treatment

Answer 6

C. Physicians need to distinguish cystic lesions from solid renal masses with necrotic components, which behave more aggressively.

Question 7

What is the main goal of the updated CUA guideline on the management of cystic renal lesions?

A) To offer guidance to physicians managing cystic renal lesions and standardize their management across Canada
B) To reduce the cost of treating cystic renal lesions
C) To introduce new surgical techniques in the management of cystic renal lesions
D) To promote research on the cause of cystic renal lesions

Answer 7

A. The main goal of the updated CUA guideline is to offer guidance to physicians managing cystic renal lesions and standardize their management across Canada.

Question 8

A patient is first identified with a complex cyst on an ultrasound. What is the recommended next step in management?

Choices:
A) Biopsy the cyst
B) Contrast-enhanced cross-sectional imaging
C) Immediate surgical intervention
D) No further steps are needed

Answer 8

B) Contrast-enhanced cross-sectional imaging
Explanation: Contrast-enhanced cross-sectional imaging is recommended to better characterize the cyst if a patient is first identified with a complex cyst on ultrasound. It provides more detailed images of the cyst.

Question 9

Which classification system is recommended for patients identified with a renal cyst?

Choices:
A) WHO classification
B) Bosniak classification
C) TNM classification
D) Fuhrman grading

Answer 9

B) Bosniak classification
Explanation: Patients identified with a renal cyst should be classified according to the v2019 Bosniak classification. The Bosniak classification is specifically designed for categorizing renal cysts.

Question 10

For patients with a Bosniak I or II cyst, what is the recommended course of action?

Choices:
A) Immediate surgical intervention
B) Follow-up imaging
C) Intervention if the cyst becomes symptomatic
D) Biopsy

Answer 10

C) Intervention if the cyst becomes symptomatic
Explanation: For patients with a Bosniak I or II cyst, intervention is only warranted if the cyst becomes symptomatic. Follow-up imaging is not recommended for these patients.

Question 11

What is the suggested follow-up period for patients with a Bosniak IIF cyst that does not demonstrate progression on imaging?

Choices:
A) 3 years
B) 5 years
C) 7 years
D) 10 years

Answer 11

B) 5 years
Explanation: For patients with a Bosniak IIF cyst that does not demonstrate progression on imaging, a follow-up of five years is suggested.

Question 12

For patients with a Bosniak III or IV complex renal cyst measuring 2–4 cm in diameter, what are the suggested management options?

Choices:
A) Immediate surgical intervention
B) Active surveillance or surgery
C) Thermal ablation
D) Only active surveillance

Answer 12

B

Question 13

What is the suggested management for a Bosniak III or IV complex renal cyst measuring >4 cm?
A. Active surveillance
B. Immediate surgical intervention
C. Surgical excision
D. Biopsy

Answer 13

Surgical excision
Explanation: For patients with a Bosniak III or IV cyst measuring >4 cm, surgical excision is suggested as the preferred strategy.

Question 14

For patients with a Bosniak III or IV complex renal cyst and significant comorbidities and/or limited life expectancy, what is the suggested management strategy?
A. Surgical intervention
B. Active surveillance
C. Observation (or watchful waiting)
D. Thermal ablation

Answer 14

Observation (or watchful waiting)
Explanation: For patients with a Bosniak III or IV complex renal cyst and significant comorbidities and/or limited life expectancy, observation (or watchful waiting) is suggested as the preferred strategy.

Question 15

In patients with a Bosniak III or IV cyst undergoing surgery, which procedure is suggested over radical nephrectomy when technically and oncologically feasible?
A. Partial nephrectomy
B. Total nephrectomy
C. Cyst ablation
D. Cyst drainage

Answer 15

Partial nephrectomy
Explanation: Partial nephrectomy is suggested over radical nephrectomy when technically and oncologically feasible, especially for small complex cysts.

Question 16

Patients diagnosed with a ≤3 cm Bosniak III or IV cyst considering treatment with thermal ablation should be informed of what?
A. The procedure has no risks
B. The high uncertainty surrounding the data on the efficacy and harms of percutaneous thermal ablation treatment compared to surgery
C. The high certainty of efficacy of thermal ablation
D. None of the above

Answer 16

The high uncertainty surrounding the data on the efficacy and harms of percutaneous thermal ablation treatment compared to surgery
Explanation: Patients diagnosed with a ≤3 cm Bosniak III or IV cyst considering treatment with thermal ablation should be informed of the higher uncertainty surrounding the data on the efficacy and harms of percutaneous thermal ablation treatment compared to surgery.

Question 17

Which patients diagnosed with a Bosniak IV cyst may be considered for biopsy?
A. All patients with a Bosniak IV cyst
B. Only patients with a significant solid component amenable to biopsy and if the result may alter management
C. Patients without a solid component
D. Patients with a cyst >4 cm

Answer 17

Only patients with a significant solid component amenable to biopsy and if the result may alter management
Explanation: Patients diagnosed with a Bosniak IV cyst may be considered for biopsy if there is a significant solid component amenable to biopsy and if the result may alter management.

Question 18

What is the concern with complex cystic lesions in the context of renal cysts?
Choices:
There is no concern
They can be difficult to differentiate from solid renal masses with necrotic components
They are always malignant
They require immediate surgical intervention

Answer 18

They can be difficult to differentiate from solid renal masses with necrotic components
Explanation:
It is especially important for physicians managing the more complex cystic lesions to differentiate them from solid renal masses with necrotic components, which behave more aggressively.

Question 19

What is the main challenge with the traditional Bosniak classification?
Choices:
It is outdated
Poor interobserver agreement
It is too complex
It is not applicable to all types of cysts

Answer 19

Poor interobserver agreement
Explanation:
The traditional Bosniak classification has traditionally been subject to poor interobserver agreement, particularly among cysts categorized as Bosniak II, IIF, and III.

Question 20

What was a major update in the Bosniak v2019 classification compared to the original Bosniak classification?
Choices:
Addition of category IIF
Removal of category III
Addition of category V
No major updates were made

Answer 20

Addition of category IIF
Explanation:
The Bosniak v2019 classification was an update of the original Bosniak classification, with one major change being the addition of a new category called category IIF.

Question 21

In which category of the Bosniak classification was most of the observed variation seen?
Choices:
Bosniak I
Bosniak II, IIF, and III
Bosniak IV
Bosniak I and IV

Answer 21

Bosniak II, IIF, and III
Explanation:
Most of the observed variation in the traditional Bosniak classification was seen among cysts categorized as Bosniak II, IIF, and III.

Question 22

What is the main challenge in managing complex cystic lesions?
Choices:
Deciding on the surgical procedure
Differentiating them from solid renal masses with necrotic components
Deciding on the imaging modality
Deciding on the follow-up period

Answer 22

Differentiating them from solid renal masses with necrotic components
Explanation:
The main challenge in managing complex cystic lesions is differentiating them from solid renal masses with necrotic components, which behave more aggressively.

Question 23

Which cysts in the Bosniak classification have most of the observed variation?
Choices:
Bosniak I
Bosniak II and IIF
Bosniak III
Bosniak IV

Answer 23

Bosniak II and IIF
Explanation:
Most of the observed variation in the traditional Bosniak classification was seen among cysts categorized as Bosniak II and IIF.

Question 24

What are the characteristics of a Bosniak category I cyst according to the v2019 CT scan classification?

1. Well-defined, thin (≤2 mm), smooth wall with no septa or calcification, and homogenous simple fluid (-9 to 20 HU). The wall may enhance.
2. One or more enhancing nodule(s) displaying >4 mm convex protrusion with obtuse margins – perpendicular axis.
3. Smooth, minimally thickening (3 mm) of one or more enhancing septa and many (≥4) smooth, thin (≤2 mm), enhancing septa.
4. One or more enhancing thick (≥4 mm) wall or septa and one or more enhancing nodule(s) displaying ≤3 mm convex protrusion with obtuse margins – perpendicular axis.

Answer 24

Well-defined, thin (≤2 mm), smooth wall with no septa or calcification, and homogenous simple fluid (-9 to 20 HU). The wall may enhance.

Explanation: A Bosniak category I cyst, according to the v2019 CT scan classification, is characterized by a well-defined, thin (≤2 mm), smooth wall with no septa or calcification. The cyst contains homogenous simple fluid (-9 to 20 HU), and the wall of the cyst may enhance.

Question 25

What is the recommended follow-up for a patient with a Bosniak category II cyst?

1. No follow-up required
2. Imaging every 6–12 months for the first year and annually for 5 years if no progression
3. Surgical excision if >4 cm
4. Thermal ablation in select cases

Answer 25

No follow-up required

Explanation: For a patient with a Bosniak category II cyst, according to the v2019 CT scan classification, no follow-up is required.

Question 26

What characterizes a Bosniak category IV cyst according to the v2019 CT scan classification?

1. One or more enhancing nodule(s) displaying >4 mm convex protrusion with obtuse margins – perpendicular axis, or one or more enhancing nodule(s) with convex protrusion of any size with acute margins.
2. Smooth, minimally thickening (3 mm) of one or more enhancing septa and many (≥4) smooth, thin (≤2 mm), enhancing septa.
3. Well-defined, thin (≤2 mm), smooth wall with no septa or calcification, and homogenous simple fluid (-9 to 20 HU). The wall may enhance.
4. One or more enhancing thick (≥4 mm) wall or septa and one or more enhancing nodule(s) displaying ≤3 mm convex protrusion with obtuse margins – perpendicular axis.

Answer 26

One or more enhancing nodule(s) displaying >4 mm convex protrusion with obtuse margins – perpendicular axis, or one or more enhancing nodule(s) with convex protrusion of any size with acute margins.

Explanation: A Bosniak category IV cyst, according to the v2019 CT scan classification, is characterized by one or more enhancing nodule(s) displaying >4 mm convex protrusion with obtuse margins – perpendicular axis, or one or more enhancing nodule(s) with convex protrusion of any size with acute margins.

Question 27

In the Bosniak v.2019 CT scan classification, what is the recommended follow-up for a Bosniak category IIF cyst?

1. No follow-up required
2. Active surveillance or surgical excision if 2–4 cm
3. Imaging every 6–12 months for the first year and annually for 5 years if no progression
4. Surgical excision if >4 cm

Answer 27

Imaging every 6–12 months for the first year and annually for 5 years if no progression

Explanation: For a Bosniak category IIF cyst, according to the v2019 CT scan classification, the recommended follow-up is imaging every 6–12 months for the first year and annually for 5 years if no progression.

Question 28

In the Bosniak v.2019 CT scan classification, what is the recommended management for a Bosniak category III cyst that measures ≤2 cm in diameter?

1. No follow-up required
2. Active surveillance
3. Active surveillance or surgical excision
4. Surgical excision if >4 cm

Answer 28

Active surveillance

Explanation: For a Bosniak category III cyst that measures ≤2 cm in diameter, according to the v2019 CT scan classification, the recommended management is active surveillance.

Question 29

What is the recommended management for a Bosniak category IV cyst that measures 2–4 cm in diameter?

1. No follow-up required
2. Active surveillance
3. Active surveillance or surgical excision
4. Surgical excision if >4 cm

Answer 29

Active surveillance or surgical excision

Explanation: For a Bosniak category IV cyst that measures 2–4 cm in diameter, according to the v2019 CT scan classification, the recommended management options are active surveillance or surgical excision.

Question 30

What is a potential management option for a Bosniak category IV cyst according to the v2019 CT scan classification?

1. No follow-up required
2. Biopsy of the solid component to confirm malignancy
3. Active surveillance
4. Imaging every 6–12 months for the first year and annually for 5 years if no progression

Answer 30

Biopsy of the solid component to confirm malignancy

Explanation: According to the v2019 CT scan classification, a potential management option for a Bosniak category IV cyst is a biopsy of the solid component to confirm malignancy.

Question 31

What are the characteristics of a Bosniak category II cyst according to the v2019 CT scan classification?

1. One or more enhancing nodule(s) displaying >4 mm convex protrusion with obtuse margins – perpendicular axis, or one or more enhancing nodule(s) with convex protrusion of any size with acute margins.
2. Well-defined, thin (≤2 mm), smooth wall with no septa or calcification, and homogenous simple fluid (-9 to 20 HU). The wall may enhance.
3. Smooth, minimally thickening (3 mm) of one or more enhancing septa and many (≥4) smooth, thin (≤2 mm), enhancing septa.
4. Six types; all with well-defined, smooth wall. Can be a cystic mass with thin (≤2 mm) and few (1–3) septa; septa and wall may enhance; calcification of any type, or a homogeneous hyperattenuating (>70 HU) at non-contrast CT, among others.

Answer 31

Six types; all with well-defined, smooth wall. Can be a cystic mass with thin (≤2 mm) and few (1–3) septa; septa and wall may enhance; calcification of any type, or a homogeneous hyperattenuating (>70 HU) at non-contrast CT, among others.

Explanation: A Bosniak category II cyst, according to the v2019 CT scan classification, comes in six types; all with a well-defined, smooth wall. It can be a cystic mass with thin (≤2 mm) and few (1–3) septa; the septa and wall may enhance; it can feature calcification of any type, or a homogeneous hyperattenuating (>70 HU) at non-contrast CT, among others.

Question 32

What is the recommended management for a Bosniak category IV cyst that measures ≤2 cm in diameter according to the Bosniak v.2019 CT scan classification?

1. No follow-up required
2. Surgical excision
3. Active surveillance
4. Imaging every 6–12 months for the first year and annually for 5 years if no progression

Answer 32

Active surveillance

Explanation: For a Bosniak category IV cyst that measures ≤2 cm in diameter, according to the v2019 CT scan classification, the recommended management is active surveillance.

Question 33

What characterizes a Bosniak category IIF cyst according to the Bosniak v.2019 CT scan classification?

1. Smooth, minimally thickened (3 mm), enhancing wall and smooth, minimally thickening (3 mm) of one or more enhancing septa, and many (≥4) smooth, thin (≤2 mm), enhancing septa.
2. Well-defined, thin (≤2 mm), smooth wall with no septa or calcification, and homogenous simple fluid (-9 to 20 HU). The wall may enhance.
3. One or more enhancing nodule(s) displaying >4 mm convex protrusion with obtuse margins – perpendicular axis, or one or more enhancing nodule(s) with convex protrusion of any size with acute margins.
4. One or more enhancing thick (≥4 mm) wall or septa and one or more enhancing nodule(s) displaying ≤3 mm convex protrusion with obtuse margins – perpendicular axis.

Answer 33

Smooth, minimally thickened (3 mm), enhancing wall and smooth, minimally thickening (3 mm) of one or more enhancing septa, and many (≥4) smooth, thin (≤2 mm), enhancing septa.

Explanation: A Bosniak category IIF cyst, according to the v2019 CT scan classification, is characterized by a smooth, minimally thickened (3 mm), enhancing wall and smooth, minimally thickening (3 mm) of one or more enhancing septa, as well as many (≥4) smooth, thin (≤2 mm), enhancing septa.

Question 34

What is the recommended management for a Bosniak category III cyst that measures ≤2 cm in diameter according to the Bosniak v.2019 CT scan classification?

1. No follow-up required
2. Surgical excision
3. Active surveillance
4. Imaging every 6–12 months for the first year and annually for 5 years if no progression

Answer 34

Active surveillance

Explanation: For a Bosniak category III cyst that measures ≤2 cm in diameter, according to the v2019 CT scan classification, the recommended management is active surveillance.

Question 35

What are the characteristics of a Bosniak category III cyst according to the Bosniak v.2019 CT scan classification?

1. Well-defined, thin (≤2 mm), smooth wall with no septa or calcification, and homogenous simple fluid (-9 to 20 HU). The wall may enhance.
2. One or more enhancing nodule(s) displaying >4 mm convex protrusion with obtuse margins – perpendicular axis, or one or more enhancing nodule(s) with convex protrusion of any size with acute margins.
3. Smooth, minimally thickened (3 mm), enhancing wall and smooth, minimally thickening (3 mm) of one or more enhancing septa, and many (≥4) smooth, thin (≤2 mm), enhancing septa.
4. One or more enhancing thick (≥4 mm) wall or septa and one or more enhancing nodule(s) displaying ≤3 mm convex protrusion with obtuse margins – perpendicular axis.

Answer 35

One or more enhancing thick (≥4 mm) wall or septa and one or more enhancing nodule(s) displaying ≤3 mm convex protrusion with obtuse margins – perpendicular axis.

Explanation: A Bosniak category III cyst, according to the v2019 CT scan classification, is characterized by one or more enhancing thick (≥4 mm) wall or septa and one or more enhancing nodule(s) displaying ≤3 mm convex protrusion with obtuse margins – perpendicular axis.

Question 36

What is the recommended management for a Bosniak category III cyst that measures 2–4 cm in diameter according to the Bosniak v.2019 CT scan classification?

1. No follow-up required
2. Surgical excision
3. Active surveillance or surgical excision
4. Imaging every 6–12 months for the first year and annually for 5 years if no progression

Answer 36

Active surveillance or surgical excision

Explanation: For a Bosniak category III cyst that measures 2–4 cm in diameter, according to the v2019 CT scan classification, the recommended management options are active surveillance or surgical excision.

Question 37

What characterizes a Bosniak category IV cyst according to the Bosniak v.2019 CT scan classification?

1. One or more enhancing nodule(s) displaying >4 mm convex protrusion with obtuse margins – perpendicular axis, or one or more enhancing nodule(s) with convex protrusion of any size with acute margins.
2. Smooth, minimally thickened (3 mm), enhancing wall and smooth, minimally thickening (3 mm) of one or more enhancing septa, and many (≥4) smooth, thin (≤2 mm), enhancing septa.
3. Well-defined, thin (≤2 mm), smooth wall with no septa or calcification, and homogenous simple fluid (-9 to 20 HU). The wall may enhance.
4. One or more enhancing thick (≥4 mm) wall or septa and one or more enhancing nodule(s) displaying ≤3 mm convex protrusion with obtuse margins – perpendicular axis.

Answer 37

One or more enhancing nodule(s) displaying >4 mm convex protrusion with obtuse margins – perpendicular axis, or one or more enhancing nodule(s) with convex protrusion of any size with acute margins.

Explanation: A Bosniak category IV cyst, according to the v2019 CT scan classification, is characterized by one or more enhancing nodule(s) displaying >4 mm convex protrusion with obtuse margins – perpendicular axis, or one or more enhancing nodule(s) with convex protrusion of any size with acute margins.

Question 38

What are the characteristics of a Bosniak category I cyst according to the v2019 CT scan classification?
Choices:
Well-defined, thin (≤2 mm), smooth wall with no septa or calcification, and homogenous simple fluid (-9 to 20 HU). The wall may enhance.
One or more enhancing nodule(s) displaying >4 mm convex protrusion with obtuse margins – perpendicular axis.
Smooth, minimally thickening (3 mm) of one or more enhancing septa and many (≥4) smooth, thin (≤2 mm), enhancing septa.
One or more enhancing thick (≥4 mm) wall or septa and one or more enhancing nodule(s) displaying ≤3 mm convex protrusion with obtuse margins – perpendicular axis.

Answer 38

Well-defined, thin (≤2 mm), smooth wall with no septa or calcification, and homogenous simple fluid (-9 to 20 HU). The wall may enhance.
Explanation:
A Bosniak category I cyst, according to the v2019 CT scan classification, is characterized by a well-defined, thin (≤2 mm), smooth wall with no septa or calcification. The cyst contains homogenous simple fluid (-9 to 20 HU), and the wall of the cyst may enhance.

Question 39

Q2:
What is the recommended follow-up for a patient with a Bosniak category II cyst?
Choices:
No follow-up required
Imaging every 6–12 months for the first year and annually for 5 years if no progression
Surgical excision if >4 cm
Thermal ablation in select cases

Answer 39

Answer:
No follow-up required
Explanation:
For a patient with a Bosniak category II cyst, according to the v2019 CT scan classification, no follow-up is required.

Question 40

Q3:
What are the management options for a patient with a Bosniak category III cyst that measures 2–4 cm in diameter?
Choices:
No follow-up required
Active surveillance
Active surveillance or surgical excision
Surgical excision if >4 cm

Answer 40

Answer:
Active surveillance or surgical excision
Explanation:
For a patient with a Bosniak category III cyst that measures 2–4 cm in diameter, according to the v2019 CT scan classification, the recommended management options are active surveillance or surgical excision.

Question 41

What is the majority of renal lesions detected by abdominal imaging classified as according to the Bosniak classification?
Choices:
Bosniak category I
Bosniak category II
Bosniak category IIF
Bosniak category III

Answer 41

Bosniak category I
Explanation:
Lesions classified as category I, also known as simple renal cysts, represent the majority of renal lesions detected by abdominal imaging.

Question 42

What is the risk of malignancy for Bosniak category II cysts according to the v2019 classification, excluding earlier studies and conservatively managed cysts?
Choices:
<5%
10%
20%
28%

Answer 42

<5%
Explanation:
If all conservatively managed Bosniak category II cysts were benign, the risk of malignancy would be less than 5%.

Question 43

What does the Bosniak category IIF represent in the Bosniak classification?
Choices:
Simple renal cysts
Cysts with minimal complexity
Moderately complex cystic lesions
Cysts whose differentiation between malignant and benign cannot be reliably made by imaging

Answer 43

Moderately complex cystic lesions
Explanation:
The Bosniak category IIF represents moderately complex cystic lesions. Any lesions not fulfilling the criteria for category II but not as complex as category III should be classified in this category.

Question 44

What is the risk of malignancy for Bosniak category IIF lesions according to the review of the literature?
Choices:
<5%
7%
10%
28%

Answer 44

Answer:
7%
Explanation:
If all conservatively managed Bosniak IIF cysts were benign, the risk of malignancy would approach 7%.

Question 45

What does the Bosniak category III encompass in the Bosniak classification?
Choices:
Simple renal cysts
Cysts with minimal complexity
Moderately complex cystic lesions
Cysts whose differentiation between malignant and benign cannot be reliably made by imaging

Answer 45

Cysts whose differentiation between malignant and benign cannot be reliably made by imaging
Explanation:
The Bosniak category III encompasses a variety of cystic lesions whose differentiation between malignant and benign cannot be reliably made by imaging.

Question 46

What is the mean malignancy rate for cysts categorized as Bosniak category IV according to the traditional classification?
Choices:
49%
60%
76%
89%

Answer 46

89%
Explanation:
Lesions in Bosniak category IV should be considered malignant until proven otherwise, with a mean malignancy rate of 89% according to the traditional classification.

Question 47

What is a characteristic of a Bosniak category IV cyst according to the v2019 classification?
Choices:
Cysts with a nodular component of any size if the margins of protrusion are acute
Cysts with one or more enhancing thickened septa/wall (≥4 mm width)
Cysts with smooth minimally thickened (3 mm) enhancing wall
Cysts with many (≥4) smooth, thin (≤2 mm), enhancing septa

Answer 47

Cysts with a nodular component of any size if the margins of protrusion are acute
Explanation:
According to the v2019 classification, Bosniak category IV cysts have a nodular component of any size if the margins of protrusion are acute.

Question 48

What is the mean malignancy rate of Bosniak III cysts according to a report by Tse et al?
Choices:
49%
60%
76%
89%

Answer 48

60%
Explanation:
According to a report by Tse et al, the prevalence of malignancy for Bosniak III cysts was 60%.

Question 49

What is a characteristic of Bosniak category IIF cysts according to the v2019 classification?
Choices:
Cysts with a nodular component of any size if the margins of protrusion are acute
Cysts with one or more enhancing thickened septa/wall (≥4 mm width)
Cysts with smooth minimally thickened (3 mm) enhancing wall
Cysts with many (≥4) smooth, thin (≤2 mm), enhancing septa

Answer 49

Cysts with many (≥4) smooth, thin (≤2 mm), enhancing septa
Explanation:
According to the v2019 classification, Bosniak category IIF cysts have many (≥4) smooth, thin (≤2 mm), enhancing septa.

Question 50

What is one characteristic of lesions classified as Bosniak category I?
Choices:
They do not contain any septa or calcifications, nor do they demonstrate enhancement following intravenous contrast agent injection.
They are slightly more complex than category I cysts.
They represent moderately complex cystic lesions.
Their differentiation between malignant and benign cannot be reliably made by imaging.

Answer 50

They do not contain any septa or calcifications, nor do they demonstrate enhancement following intravenous contrast agent injection.
Explanation:
Bosniak category I lesions are simple renal cysts characterized by their regular contour and a clear interface with the renal parenchyma. They do not contain any septa or calcifications, nor do they demonstrate enhancement following intravenous contrast agent injection.

Question 51

For patients with a Bosniak I or II cyst, is followup imaging recommended?
Choices:
Yes
No
Depends on the patient’s symptoms
Depends on the cyst’s growth

Answer 51

No
Explanation: According to the recommendation 4, followup imaging is not recommended for patients with a Bosniak I or II cyst.

Question 52

When is intervention warranted for patients with a Bosniak I or II cyst?
Choices:
When the cyst becomes symptomatic
When the cyst grows over time
When the cyst transforms into a more complex cyst
Intervention is not warranted

Answer 52

When the cyst becomes symptomatic
Explanation: According to the recommendation 5, intervention for patients with a Bosniak I or II cyst is only warranted if the cyst becomes symptomatic.

Question 53

What is the natural history of Bosniak category I cysts?
Choices:
They remain the same size over time
They shrink over time
They grow over time
They transform into more complex cysts

Answer 53

They grow over time
Explanation: The natural history of Bosniak category I cysts is that the majority will grow over time.

Question 54

Is growth of a Bosniak category I cyst necessarily considered a sign of malignancy?
Choices:
Yes
No
Depends on the rate of growth
Depends on the patient’s symptoms

Answer 54

No
Explanation: Growth of a Bosniak category I cyst should not necessarily be considered a sign of malignancy.

Question 55

What happens when there is doubt as to the categorization of Bosniak category II cysts based on imaging characteristics?
Choices:
They should be considered as being Bosniak category IIF lesions and followed accordingly
They should be considered as being Bosniak category I lesions and followed accordingly
They should be considered as being Bosniak category III lesions and followed accordingly
They should be considered as being Bosniak category IV lesions and followed accordingly

Answer 55

They should be considered as being Bosniak category IIF lesions and followed accordingly
Explanation: When there is doubt as to their categorization based on imaging characteristics, these lesions should be considered as being Bosniak category IIF lesions and followed accordingly.

Question 56

What is the typical behavior of Bosniak category II cysts, even if malignant?
Choices:
They behave in a relatively benign fashion
They behave aggressively
They transform into more complex cysts
They shrink over time

Answer 56

They behave in a relatively benign fashion
Explanation: Even if malignant, most Bosniak category II cysts behave in a relatively benign fashion.

Question 57

What treatment options are available for symptomatic Bosniak category I cysts?
Choices:
Percutaneous management (aspiration ± sclerotherapy) or surgery
Chemotherapy
Radiation therapy
Immunotherapy

Answer 57

Percutaneous management (aspiration ± sclerotherapy) or surgery
Explanation: Treatment options for symptomatic Bosniak category I cysts include percutaneous management (aspiration ± sclerotherapy) or surgery.

Question 58

According to the literature, what percentage of Bosniak category II lesions are malignant?
Choices:
<5%
About 10%
About 28%
About 60%

Answer 58

About 10%
Explanation: According to the literature, approximately 10% of the operated category II cysts are malignant.

Question 59

: What is the estimated true risk of malignancy among Bosniak category II cysts?
Choices:
<5%
About 10%
About 28%
About 60%

Answer 59

<5%
Explanation: Even if malignant, most Bosniak category II cysts behave in a relatively benign fashion. Thus, the risk of malignancy for these lesions would be <5%.

Question 60

What is the suggested followup for patients with a Bosniak IIF cyst?
1. A followup every 6-12 months for the first year, and then yearly if the cyst is stable
2. A followup every 3-6 months for the first year, and then every six months if the cyst is stable
3. A followup every year for five years
4. No followup is necessary unless the cyst becomes symptomatic

Answer 60

A followup every 6-12 months for the first year, and then yearly if the cyst is stable
Explanation:
The guidelines suggest a followup every 6-12 months for the first year, and then yearly thereafter if the cyst is stable for patients with a Bosniak IIF cyst.

Question 61

For patients with a Bosniak IIF cyst that do not demonstrate progression on imaging, how long is a followup suggested?
1. One year
2. Two years
3. Three years
4. Five years

Answer 61

Answer:
Five years
Explanation:
A followup of five years is suggested for Bosniak IIF cysts that do not demonstrate progression on imaging.

Question 62

What is the traditional belief about the percentage of Bosniak category IIF cysts that will progress in complexity over time?
1. Approximately 5%
2. Approximately 10%
3. Approximately 15%
4. Approximately 20%

Answer 62

Answer:
Approximately 15%
Explanation:
The traditional belief was that approximately 15% of category IIF cysts will progress in complexity over time.

Question 63

What are more recent reports suggesting about the percentage of Bosniak category IIF cysts that will progress in complexity over time?
1. Approximately 5%
2. Approximately 10%
3. Approximately 15%
4. Approximately 20%

Answer 63

Approximately 5%
Explanation:
More recent reports have suggested that the rate of progression in complexity of Bosniak category IIF cysts is closer to 5%.

Question 64

When is progression more likely to occur in Bosniak category IIF cysts?
1. Within the first two years
2. After two years
3. After three years
4. Progression is not likely to occur

Answer 64

Within the first two years
Explanation:
Progression is more likely to occur within the first two years.
 

Question 65

Is there an identified clear progression pattern for Bosniak IIF cysts?
1. Yes
2. No

Answer 65

No
Explanation:
Unfortunately, a clear progression pattern is yet to be identified for Bosniak IIF cysts.

Question 66

Is there an identified clear progression pattern for Bosniak IIF cysts?
1. Yes
2. No

Answer 66

No
Explanation:
Unfortunately, a clear progression pattern is yet to be identified for Bosniak IIF cysts.

Question 67

What is the malignancy rate and metastatic potential of Bosniak IIF cysts?
1. High malignancy rate and high metastatic potential
2. Low malignancy rate and low metastatic potential
3. High malignancy rate and low metastatic potential
4. Low malignancy rate and high metastatic potential

Answer 67

Low malignancy rate and low metastatic potential
Explanation:
Bosniak IIF cysts have a low malignancy rate and if malignant, a low metastatic potential.

Question 68

What is the risk of using closer monitoring for Bosniak IIF cysts?
1. May potentially reduce the detection of a progression if the changes in the cysts from imaging to imaging are very small
2. May lead to unnecessary interventions
3. May lead to progression of the cyst
4. There is no risk in closer monitoring

Answer 68

May potentially reduce the detection of a progression if the changes in the cysts from imaging to imaging are very small
Explanation:
Closer monitoring may potentially reduce the detection of a progression if the changes in the cysts from imaging to imaging are very small.

Question 69

Which imaging modality may be used to better delineate the septa number, septa and/or wall thickness, solid component, and the enhancement in Bosniak IIF cysts?
1. Contrast-enhancement ultrasound (CEUS)
2. Computed tomography (CT)
3. Magnetic resonance imaging (MRI)
4. Plain X-ray

Answer 69

Contrast-enhancement ultrasound (CEUS)
Explanation:
CEUS may be used to better delineate the septa number, septa and/or wall thickness, solid component, and the enhancement in Bosniak IIF cysts.

Question 70

What combination of imaging modalities may be used if a Bosniak IIF cyst is stable on followup?
1. Ultrasound in combination with contrast-enhanced CT or MRI
2. Contrast-enhanced CT in combination with MRI
3. Ultrasound in combination with plain X-ray
4. Contrast-enhanced CT in combination with plain X-ray

Answer 70

Ultrasound in combination with contrast-enhanced CT or MRI
Explanation:
Ultrasound in combination with contrast-enhanced CT or MRI may be used if the lesion is stable on followup.

Question 71

What is the suggested follow-up schedule for stable Bosniak IIF cysts after the first year?
1. Every 6 months
2. Yearly
3. Every 2 years
4. No follow-up is necessary

Answer 71

Yearly
Explanation:
It is suggested to follow up stable Bosniak IIF cysts yearly after the first year.

Question 72

Q: What is the malignancy rate for Bosniak category III and IV lesions respectively?

Answer 72

Studies of resected Bosniak III and IV lesions have found that 50–60% and 80–90% of these cysts, respectively, are malignant.

Question 73

What is the most common malignant cystic renal mass?

Answer 73

The vast majority of malignant cystic renal masses are multilocular cystic renal cell carcinomas (mcRCC).

Question 74

How has the International Society of Urological Pathology (ISUP) modified its terminology for mcRCC?

Answer 74

The ISUP now recommends calling these lesions multilocular cystic renal neoplasm with low malignant potential.

Question 75

Why do mcRCCs have a better prognosis than solid RCCs?

Answer 75

One potential explanation for this better prognosis is that the majority of mcRCCs tumor volume is fluid and thus, the actual tumor burden is much lower when compared to similar-sized solid tumors.

Question 76

How has the treatment approach for Bosniak III and IV cysts evolved recently?

Answer 76

Although the traditional treatment dogma was to surgically excise all Bosniak III and IV cysts, recent direct and indirect evidence suggest that this may lead to significant overtreatment. Given the relatively high rate of benign histology and relatively indolent nature even if malignant, there is emerging evidence suggesting that these Bosniak III and IV cysts, like small renal masses, can be safely managed by active surveillance.

Question 77

What is the preferred management strategy for patients with a Bosniak III or IV cyst measuring ≤2 cm?

Answer 77

Active surveillance is suggested as the preferred management strategy for patients with a Bosniak III or IV cyst measuring ≤2 cm.

Question 78

What should be offered to patients with a Bosniak III or IV cyst under active surveillance?

Answer 78

Patients with a Bosniak III or IV cyst under active surveillance should be offered definitive treatment when the oncological risk increases or when the patient wishes to undergo treatment for personal reasons. They should be transitioned to watchful waiting when the competing risks outweigh the benefits of treatment

Question 79

What is the proposed new stage for mcRCC, and why?

Answer 79

Some experts have suggested abandoning the current pathological T staging for mcRCC and to reassign them a new stage called pT1c (c for cystic). This suggestion is due to the observation that the majority of mcRCCs tumor volume is fluid and thus, the actual tumor burden is much lower when compared to similar-sized solid tumors.

Question 80

What is the suggested followup scheme for patients with a Bosniak III or IV cyst under active surveillance?

Answer 80

In the absence of specific criteria, it is the panel members’ opinion that the same followup scheme as the one proposed for the small renal mass population should be observed (i.e., abdominal imaging every 3–6 months for the first year, and then once every 6–12 months, if the cyst remains stable).

Question 81

What is the role of thermal ablation in the management of Bosniak III or IV cysts?

Answer 81

Thermal ablation therapies also remain an option in well-informed patients

Question 82

What are the criteria used to define progression in the small renal mass population?

Answer 82

In the absence of specific criteria, it is the panel members’ opinion that the same criteria as the ones used to define progression in the small renal mass population should be applied (i.e., growth of tumor to >4 cm, consecutive growth rate >0.5 cm/year, progression to metastases, and patient’s choice).

Question 83

According to recommendation 14, who should be informed of the higher uncertainty surrounding the data on the efficacy and harms of percutaneous thermal ablation treatment compared to surgery?

All patients with Bosniak III or IV cyst
Patients diagnosed with a ≤3 cm Bosniak III or IV cyst considering treatment with thermal ablation
Patients with Bosniak I or II cyst
Patients diagnosed with a >3 cm Bosniak III or IV cyst considering treatment with thermal ablation

Answer 83

Patients diagnosed with a ≤3 cm Bosniak III or IV cyst considering treatment with thermal ablation
Explanation: According to recommendation 14, patients diagnosed with a ≤3 cm Bosniak III or IV cyst considering treatment with thermal ablation should be informed of the higher uncertainty surrounding the data on the efficacy and harms of percutaneous thermal ablation treatment compared to surgery.

Question 84

What is the potential role of thermal ablation therapies in the treatment of cystic renal lesions?
Choices:
They are the first-line treatment
They are considered an alternative in select cases
They are not recommended
They are used in all cases

Answer 84

They are considered an alternative in select cases
Explanation: Thermal ablation therapies may be considered an alternative in select cases, mainly extrapolating from the small renal mass literature.

Question 85

What is the role of radiofrequency ablation (RFA) in the treatment of cystic renal lesions?
Choices:
It is the first-line treatment
It is used in all cases
It should be reserved to patients with small (generally ≤3 cm) Bosniak category III and IV cysts who are poor operative candidates
It is not recommended

Answer 85

It should be reserved to patients with small (generally ≤3 cm) Bosniak category III and IV cysts who are poor operative candidates
Explanation: Given the limited data, RFA should be reserved to patients with small (generally ≤3 cm) Bosniak category III and IV cysts who are poor operative candidates and in whom active surveillance is not being considered.

Question 86

What is the role of cryotherapy in the management of Bosniak III or IV cysts?
Choices:
It is the first-line treatment
It is well-defined and commonly used
It is not well-defined, with only a handful of cases reported to have been treated by the approach in the literature
It is not recommended

Answer 86

It is not well-defined, with only a handful of cases reported to have been treated by the approach in the literature
Explanation: The role of cryotherapy in the management of Bosniak III or IV cysts is not well-defined, with only a handful of cases reported to have been treated by the approach in the literature.

Question 87

What should patients opting for thermal ablation therapies be made aware of?
Choices:
The high success rate of these therapies
The sparse literature on the management of cystic renal lesions using these approaches
The low risk of complications associated with these therapies
The cost-effectiveness of these therapies

Answer 87

The sparse literature on the management of cystic renal lesions using these approaches
Explanation: Patients opting for thermal ablation therapies should be made aware of the sparse literature on the management of cystic renal lesions using these approaches.

Question 88

Question: What is the current understanding of the role of renal tumor biopsy (RTB) in managing solid renal masses?
Choices:
RTB is not reliable and does not contribute significantly to the management of solid renal masses
RTB is safe, accurate, and reliable and can help decrease overtreatment rates
RTB is only useful for diagnosing benign tumors
RTB should only be used if the tumor is larger than 5 cm in diameter

Answer 88

RTB is safe, accurate, and reliable and can help decrease overtreatment rates
Explanation: There is substantial evidence supporting the role of renal tumor biopsy (RTB) for the pretreatment identification of the histology of solid renal masses. RTB is safe, accurate, and reliable, and it has been shown to decrease overtreatment rates when used in the management of solid small renal masses.

Question 89

What is the general consensus about using RTB in cystic renal masses?
Choices:
RTB is highly reliable for diagnosing cystic lesions
RTB is significantly less informative for diagnosing cystic lesions than for solid ones
RTB is only used for cystic lesions larger than 5 cm in diameter
RTB is the preferred method for diagnosing all cystic lesions

Answer 89

RTB is significantly less informative for diagnosing cystic lesions than for solid ones
Explanation: There is evidence that RTBs are significantly less informative for the diagnosis of cystic lesions than for solid ones. Therefore, the utility of RTB in cystic lesions is less than that observed with solid renal masses.

Question 90

Question: In what cases might a biopsy be considered for Bosniak IV cysts?
Choices:
If the cyst is larger than 5 cm
If there is a significant solid component amenable to biopsy and if the result may alter management
If the cyst has been present for more than 5 years
In all cases of Bosniak IV cysts

Answer 90

Answer: If there is a significant solid component amenable to biopsy and if the result may alter management
Explanation: For Bosniak IV cysts, a biopsy of the solid component may be considered to confirm the presence of a malignant tumor and to help with decision-making if the result has the potential to alter management or if a treatment by thermal ablation is planned.