Canadian Urological Association guideline: Management of small renal masses Flashcards
What routine laboratory investigations are recommended for patients diagnosed with SRM?
Serum creatinine and glomerular filtration rate. (Clinical principle)
What imaging modality is suggested for SRM discovered incidentally on routine imaging?
A multiphasic, contrast-enhanced abdominal CT or MRI scan. (Clinical principle)
What imaging is suggested to assess for pulmonary metastases in patients with suspected renal malignancy?
Baseline chest X-ray. (Conditional recommendation, low certainty in evidence of effects)
In patients with SRM and pre-existing renal dysfunction considering radical nephrectomy, what additional test might be offered?
Renal scintigraphy, especially if results may alter management. (Clinical principle)
When is a renal mass biopsy offered to patients with SRM?
When the biopsy results may change their management. (Adopted from KCRNC consensus; expert opinion)
What should be offered to patients with features suspicious of hereditary renal cell carcinoma?
Genetic counselling. (Adopted from CUA guideline on genetic screening for hereditary RCC; expert opinion)
What’s the recommended strategy for patients with SRM suspicious of malignancy AND significant comorbidities/limited life expectancy?
Observation or watchful waiting. (Strong recommendation, high certainty in evidence of effects)
What’s the preferred management strategy for suspected renal malignancy <2 cm in diameter?
Active surveillance due to their slow growth rate and low probability of aggressive histology. (Conditional recommendation, moderate certainty in evidence of effects)
For suspected renal malignancy of 2-4 cm, what are the suggested management options?
Active surveillance and definitive treatment (partial nephrectomy or percutaneous thermal ablation). (Conditional recommendation, low certainty in evidence of effects)
How should treatment choices be made for patients with suspected renal malignancy?
Personalized, using a shared decision-making approach, considering tumor characteristics, patient factors, and patient preferences/values. (Expert opinion)
What treatments are suggested for those who prefer upfront definitive treatment for suspected renal malignancy?
Surgery or percutaneous thermal ablation. (Conditional recommendation, low certainty in evidence of effects)
What should patients be informed about regarding the uncertainty surrounding percutaneous thermal ablation vs. surgery?
There’s higher uncertainty about the efficacy and harms of percutaneous thermal ablation compared to surgery. (Expert opinion)
When should a renal mass biopsy be performed for patients opting for percutaneous thermal ablation?
Prior to, or at the time of thermal ablation. (Adopted from KCRNC consensus; expert consensus)
For malignant SRM undergoing surgery, which procedure is recommended over the other?
Partial nephrectomy is recommended over radical nephrectomy. (Strong recommendation, moderate certainty in evidence of effects)
: For suspected malignancy undergoing partial nephrectomy, which approach is suggested if technically feasible and oncologically safe?
Minimally invasive approach (robotic-assisted or conventional laparoscopy) over an open approach. (Conditional recommendation, moderate certainty in evidence of effects)
For suspected malignancy undergoing radical nephrectomy, which approach is recommended?
Conventional laparoscopic approach over open or robotic-assisted approaches. (Strong recommendation, moderate certainty in evidence of effects)
For those undergoing percutaneous thermal ablation for suspected malignancy, which two management options yield similar outcomes?
Cryoablation and radio-frequency ablation. (Conditional recommendation, moderate certainty in evidence of effects)
What are the well-accepted factors that define oncological risk in patients under active surveillance?
Growth of tumor to >4 cm, consecutive growth rate >0.5 cm/year, progression to metastases, and patient’s choice. (Clinical principle)
If there’s suspected tumor growth on ultrasound, what is the recommended next step before intervention?
Undergo cross-sectional imaging to confirm growth. (Expert opinion)
What is the suggested imaging for those managed by active surveillance until definitive treatments are no longer considered?
Routine abdominal ultrasound. (Conditional recommendation, low certainty in evidence of effects)
Alongside abdominal imaging, what other imaging is suggested for patients on active surveillance?
Chest X-ray imaging. (Conditional recommendation, low certainty in evidence of effects)
How frequently should abdominal and chest imaging be performed for patients with SRM on active surveillance?
Consensus varies. Abdominal imaging ranges from every 3-6 months for the first year to 6-12 months if the lesion remains stable. Chest imaging varies from for-cause to once a year. (Expert opinion)
What follow-up is recommended for patients with RCC who have undergone definitive treatment?
Routine chest and abdominal imaging to rule out recurrence or metastasis. (Adopted from CUA guideline for follow-up of non-metastatic RCC; expert opinion)
What action is recommended for patients with an eGFR <45 ml/min/1.73m2 or progressive CKD post-definitive treatment?
Consider referral to a nephrologist or their general practitioner, especially if associated with proteinuria. (Adopted from CUA guideline for follow-up of non-metastatic RCC; conditional recommendation, low certainty in evidence of effects)
What has led to the increased incidence of small renal masses (SRM) detection worldwide?
The increasing use of abdominal imaging.
: What percentage of SRM are benign?
10-30%.
What consequence has the rise in SRM detection had concerning renal cell carcinoma (RCC)?
There’s been an increase in the detection of RCC.
: How many Canadians were estimated to be diagnosed with kidney cancer in 2020?
Approximately 7500.
: Name the well-accepted treatment strategies available to manage SRM.
Surgical excision (partial/radical nephrectomy), thermal ablation (cryoablation/radio-frequency ablation), and active surveillance.
Why do most patients with many small cancers that behave indolently receive invasive treatments?
Even though many of these cancers have low metastatic potential, the vast majority of patients still receive invasive treatments.
Which diagnostic test has been proposed to decrease overtreatment of patients with SRM?
Renal mass biopsies.
What is crucial in the management of patients with SRM?
There’s no “one-size-fits-all” strategy. Shared decision-making that considers tumor characteristics, competing medical risks, and patient values/preferences is vital for individualized management plans.
What is the main objective of the Canadian Urological Association guideline on the management of SRM?
To provide evidence-based recommendations to assist clinicians and patients in the evaluation and management of SRM.
What routine laboratory investigations are suggested for patients diagnosed with an SRM?
Serum creatinine (Cr) and glomerular filtration rate (GFR).
Why is routine blood work like serum Cr and GFR suggested for patients with an SRM suspicious for renal malignancy?
To better counsel patients on the potential harms of treatments.
What additional test is suggested for patients with renal impairment being considered for invasive treatment?
Urinalysis to screen for proteinuria.
What alternative test can be used instead of urinalysis to screen for proteinuria in patients with renal impairment?
Urine albumin-to-creatinine ratio.
What other blood tests may be considered for patients being considered for an invasive treatment?
A complete blood count and a coagulation study.
When might synchronous metastasis be found in patients diagnosed with an SRM?
Although uncommon, it can be found in patients diagnosed with an SRM.
What tests are suggested for patients with features suspicious for liver metastases?
Liver function tests.
Which tests should be ordered for patients presenting with bone pain?
Alkaline phosphatase, serum calcium, and lactate dehydrogenase (LDH).
What tests are suggested for patients where urothelial cancer is suspected?
Urine cytology and endoscopic assessment.
What percentage of all SRM are benign, and how does the metastatic potential of the malignant lesions usually rank?
10-30% of all SRM are benign. The majority of malignant lesions have low metastatic potential.
If a SRM is incidentally discovered on routine imaging, what further imaging is recommended?
A multiphasic, contrast-enhanced, abdominal CT or MRI.
How many malignant SRM are typically metastatic at the time of diagnosis?
Under 2% of malignant SRM will be metastatic at the time of diagnosis.
What is the main use of contrast-enhanced abdominal imaging in SRM diagnosis?
To exclude the presence of visceral metastases and tumor thrombus.
What is the most common site of metastases for SRM?
The lungs.
In the context of SRM diagnosis, why is a chest X-ray suggested over a chest CT as the initial imaging of choice?
Given the low incidence of metastasis and the lower harms and costs to the healthcare system compared to chest CT. If abnormalities are detected on the chest X-ray, a chest CT should then be performed.
When should bone scintigraphy and brain imaging be performed for SRM patients?
Only for-cause in patients with symptoms, as most bone/brain metastases are symptomatic at diagnosis.
In which SRM patients might renal scintigraphy be considered?
In patients with renal impairment and in whom a radical nephrectomy is considered or in whom the assessment of differential renal function could alter management.
What percentage of Small Renal Masses (SRM) turn out to be benign?
10–30% of SRM are benign.
Why are renal mass biopsies performed on SRM?
To identify the histology of a SRM before treatment, to inform management and decrease overtreatment, since imaging modalities cannot reliably differentiate benign lesions from malignant ones.
When should a patient be offered a renal mass biopsy?
When the result of the biopsy may alter their management.
Under which circumstance should a renal biopsy not be performed?
For patients where the outcome will not influence treatment decision, such as someone not fit for invasive treatment or a patient who seeks surgical removal regardless of histology.
What is the median diagnostic rate of biopsies as shown by a recent meta-analysis by Marconi et al?
92% (interquartile rate [IQR] 80.6–96.8%).
How can a renal mass biopsy be helpful beyond identifying benign lesions?
It can be helpful for risk stratification. For instance, growth rates vary by RCC subtype, with clear-cell RCC showing the fastest growth rates.
What is the complication rate of renal mass biopsies?
Median overall complication rate is 8.1% (IQR 2.7–11.1%), with most complications being Clavien-Dindo <2 (>99%).
What is the reported risk associated with biopsy tract seeding with tumor?
The evidence remains controversial and this risk is likely very low.
Why should patients be informed about the benefits and harms of renal mass biopsies before proceeding?
Due to its non-diagnostic rate, the unknown false-negative rate, and the variability in outcomes based on experience of the biopsy centers and patient/tumor factors.
What factors may influence biopsy outcomes?
Size of the mass, consistency (cystic or necrosis component), location (exophytic vs. endophytic), and skin-to-tumor distance.
How should the decision to proceed with a biopsy be approached?
Through a shared decision-making approach after weighing the potential benefits and harms of the diagnostic test and discussing the patients’ preferences and values.
What is recommended for patients with features suspicious of hereditary RCC, according to the Canadian Urological Association guideline?
Patients with features suspicious of hereditary RCC should be offered genetic counselling.
Who is responsible for the detailed discussion on the role of genetic testing in the management of kidney cancer in the CUA clinical practice guideline?
Reaume et al.
According to the Canadian Urological Association guideline, which patients should be offered genetic counselling and referred for genetic assessment?
Patients with the criteria presented in Table 1.
(True/False) The role of genetic testing in the management of kidney cancer is briefly mentioned and not explored in depth in the CUA guidelines.
False. The role of genetic testing in the management of kidney cancer is extensively discussed in a separate CUA clinical practice guideline.
Which patients with renal tumors should be recommended for genetic counselling, according to the Canadian Urological Association?
Patients with bilateral or multifocal tumors
Early age of onset (≤45 years of age)
1st or 2nd degree relative with any renal tumor
History of pneumothorax, lymphangiomyomatosis, or childhood seizure disorder (either personal history or in 1st degree relative)
Presence of skin leiomyomas or fibrofolliculomas/trichodisomas (either personal history or in 1st degree relative)
Concomitant tumors: Pheochromocytoma, paraganglioma, hemangioblastoma (retina, brainstem, cerebellum or spinal cord), early onset of multiple uterine fibroids (either personal history or in 1st degree relative)
Patients with non-clear-cell carcinoma with unusual associated features (e.g., chromophobe, oncocytic, or hybrid tumors)
Patients who report a family member with a known clinical or genetic diagnosis that places them at higher risk of kidney cancer diagnosis
When should patients with non-clear-cell carcinoma be recommended for genetic counselling?
When the non-clear-cell carcinoma has unusual associated features, such as chromophobe, oncocytic, or hybrid tumors.
How does a family member’s reported clinical or genetic diagnosis relate to recommending genetic counselling for renal tumor patients?
If a patient reports a family member with a known clinical or genetic diagnosis that places them at higher risk of being diagnosed with kidney cancer, they should be recommended for genetic counselling.
Fig. 1. Algorithm for the management of small renal masses
For patients with a Small Renal Mass (SRM) suspicious for renal malignancy AND significant comorbidities and/or limited life expectancy, what is the recommended strategy?
Observation (or watchful waiting) is recommended as the preferred strategy. (Strong recommendation, high certainty in evidence of effects).
For patients with a suspected renal malignancy measuring <2 cm in diameter, what is the suggested strategy?
Active surveillance is suggested as the preferred strategy, given their slow growth rate and low probability of aggressive histology. (Conditional recommendation, moderate certainty in evidence of effects).
For patients with a suspected renal malignancy measuring 2–4 cm in diameter, what are the suggested management options?
Both active surveillance and definitive treatment (partial nephrectomy or percutaneous thermal ablation) are suggested management options. (Conditional recommendation, low certainty in evidence of effects).
For patients with a suspected renal malignancy, what approach should be used for treatment choice?
The choice of treatment should be personalized using a shared decision-making approach, after proper counselling and considering tumor characteristics, patient factors, and patient preferences and values. (Expert opinion).
How many well-documented management options are there for the treatment of SRM? And what about the quality of evidence comparing these options?
There are three well-documented management options for the treatment of SRM. The evidence comparing each of these treatment options is of low quality, and no one option has been demonstrated to be superior to another in a randomized controlled trial.
How should the choice of treatment for SRM be determined?
The choice of treatment should be personalized using a shared decision-making approach. This involves proper counselling according to each patient’s values and preferences, while also considering the patient’s competing risks and tumor characteristics.
Are there any tools to estimate the risk of other-cause mortality for SRM patients?
Are there any tools to estimate the risk of other-cause mortality for SRM patients?
Is there a decision aid available to inform patients diagnosed with a SRM?
Yes, a decision aid has been developed to inform patients diagnosed with a SRM, available at https://decisionaid.ohri.ca/docs/das/Small_Kidney_Tumour_Treatment.pdf. It may help facilitate shared decision-making.
What are the two main expectant management strategies for small renal masses?
Active surveillance and watchful waiting.
How does active surveillance differ from watchful waiting in managing small renal masses?
Active surveillance involves serial, scheduled imaging to monitor the mass, offering definitive treatment if disease progression is evident or patient preferences change. Watchful waiting is reserved for patients with limited life expectancy, with treatment considered only for symptom palliation from disease progression, not for cure. No regular imaging followup is required unless clinically indicated.
What outcomes are associated with active surveillance according to the meta-analysis of patients with a Small Renal Mass (SRM)?
Cancer-specific survival similar to other treatment strategies, and a low associated risk of developing metastasis after short- to mid-term followup.
What findings were made from the DISSRM study regarding active surveillance for small renal masses?
Most tumors grow slowly with a median growth rate of <0.1 cm/year. Approximately 10–15% of patients discontinue active surveillance in favor of definitive therapy over time.
How does the quality of life scores compare between active surveillance and immediate intervention cohorts?
Immediate intervention cohort had higher quality of life scores at baseline and throughout followup. However, mental health domains were not negatively affected while on active surveillance, and even improved over time.
Is active surveillance safe for younger patients?
Yes, recent evidence demonstrated that active surveillance is safe among younger patients, with no significant difference in cancer-specific survival and overall survival among patients <60 years of age managed by either definitive treatment or active surveillance.
How does the rate of progression to definitive treatment compare for lesions <2 cm versus lesions between 2–4 cm?
Rate of progression to definitive treatment was lower among patients with a lesion <2 cm (15.1%) compared to patients with a lesion measuring 2–4 cm (33.3%).
What should be noted regarding the active surveillance series’ duration and patient demographics?
Most active surveillance series have relatively short followup (median 42 months, range 1–137 months) and are based on older, more comorbid patients compared to surgical series.
What is the suggested preferred management strategy for patients with a lesion measuring <2 cm?
Active surveillance is suggested as the preferred management strategy. However, immediate, definitive treatment remains an option and should be discussed.
For patients with a lesion measuring 2–4 cm, what was the consensus regarding the preferred management strategy?
There was no consensus. While active surveillance should be offered as an option, nearly 40% of the panel members felt that definitive treatment (surgery or thermal ablation) should be the choice. Biopsy may also inform the management decision for patients considering active surveillance.
List three categories of characteristics that may influence the treatment decision for small renal masses.
Patient
Tumor
Hospital-level
What patient-related factor reflects their wishes or desires in treatment decision-making?
Patient preferences.
Which index score might be relevant when considering the physical robustness of a patient with a small renal mass?
Frailty index score.
What are three tumor-related characteristics that can influence treatment decisions?
Size
Location
Number of lesions
The histological examination of a renal tumor can be obtained from which diagnostic method?
Renal mass biopsy.
What score measures the complexity of a renal tumor?
Nephrometry score.
From a hospital-level perspective, what are three aspects of healthcare access that might influence treatment decisions for small renal masses?
Access to healthcare
Access to thermal-ablative therapies locally
Access to minimally invasive surgery locally
What are the suggested definitive treatments for patients with a suspected renal malignancy who prefer upfront management?
Surgery or percutaneous thermal ablation.
Why should patients with a Small Renal Mass (SRM) be informed regarding percutaneous thermal ablation?
There’s higher uncertainty surrounding the data on the efficacy and harms of percutaneous thermal ablation compared to surgery.
When should a renal mass biopsy be performed for patients choosing percutaneous thermal ablation?
Either prior to, or at the time of thermal ablation.
What is the significant drawback in the current evidence comparing outcomes of surgery and percutaneous thermal ablation for SRM management?
The evidence is mainly based on retrospective studies, making them prone to selection bias.
Is the local recurrence rate higher after thermal ablation or partial nephrectomy?
Local recurrence is higher after thermal ablation, but with multiple ablative treatments, the local recurrence-free survival becomes comparable to partial nephrectomy.
What were the findings of the most recent meta-analysis on the topic reported by the European Association of Urology Renal Cell Cancer Guideline Panel in 2020?
Percutaneous ablation appears safe in terms of adverse events and complications. However, its long-term oncological outcome compared to partial nephrectomy remains uncertain due to high or uncertain risk of bias across studies.
What advantage does surgery offer compared to thermal ablation?
Surgery provides a definitive pathology specimen, which can be important for genetic counselling considerations.
What factors should influence the choice of treatment for SRM?
The choice should be individualized based on each patient’s values and preferences, and according to patient, tumor, and hospital-level characteristics.
What’s the recommendation if a patient chooses percutaneous thermal ablation as their treatment?
he patient should undergo a renal mass biopsy either prior to or at the time of thermal ablation for histological confirmation and to tailor the follow-up strategy.
What is the recommended definitive treatment for patients with suspected malignant SRM undergoing surgery?
Partial nephrectomy is recommended over radical nephrectomy.
What was the primary finding from the randomized controlled trial comparing oncological outcomes of patients with localized renal mass treated with radical vs. partial nephrectomy between 1992 and 2003?
Comparable 10-year cancer-specific survival for both options, but an improved 10-year overall survival in favor of radical nephrectomy.
Based on the Cochrane review published in 2017, what was the hazard ratio indicating time to death of any cause for partial nephrectomy compared to radical nephrectomy?
Hazard ratio (HR) of 1.5, 95% confidence interval (CI) 1.03–2.18.
In the context of easily resectable tumors with a normal contralateral kidney, how do significant harms compare between partial and radical nephrectomy?
There is no difference in the rate of significant harm between both surgeries.
What is one potential explanation for improved survival with partial nephrectomy over radical nephrectomy?
Partial nephrectomy results in increased renal function preservation and subsequent decrease in cardiovascular events compared to radical nephrectomy.
Partial nephrectomy results in increased renal function preservation and subsequent decrease in cardiovascular events compared to radical nephrectomy.
For patients in whom a partial nephrectomy or percutaneous thermal ablation isn’t feasible even in experienced centers, or for those who are unwilling to accept the short-term risks of partial nephrectomy/thermal ablation compared to radical nephrectomy. Also for cases where there’s a potential risk of removing the entire organ for a benign lesion, considering a preoperative renal mass biopsy.
Name the three mentioned nephrometry scoring systems developed to communicate renal tumor complexity.
RENAL (radius, exophytic/endophytic, nearness, anterior/posterior, location), PADUA (preoperative aspects and dimensions used for an anatomical), and SPARE (Simplified PADUA Renal) nephrometry scores.
What outcomes have the RENAL and PADUA nephrometry scoring systems been shown to be predictive of?
They predict the length of hospital stay, tumor pathology, surgical margins, tumor growth rate, renal function outcomes, and survival. The RENAL nephrometry score also predicts outcomes and complications following percutaneous ablation.
What is a significant limitation of using nephrometry scoring systems?
Interobserver variability in assessments and inconsistent associations with outcome measures.
Why are nephrometry scoring systems valuable despite their limitations?
They provide a common language that can standardize classification of renal tumor complexity, allow for the comparison of surgical outcomes, enhance patient counselling, and inform surgical decision-making.
What are the key renal nephrometry scoring systems mentioned in the Canadian Urological Association guideline?
R.E.N.A.L., PADUA, SPARE, and Simplified PADUA system.
In the R.E.N.A.L scoring system, what does “R” stand for, and how is it scored?
R stands for Radius (maximal diameter).
≤4 cm: 1 point
4 cm & <7 cm: 2 points
≥7 cm: 3 points
In the R.E.N.A.L scoring system, how is Exo/endophytic properties (“E”) scored?
≥50% exophytic: 1 point
<50% exophytic: 2 points
Entirely endophytic: 3 points
What does “N” represent in the R.E.N.A.L scoring system, and how is its proximity to the collecting system scored?
“N” stands for Nearness to collecting system.
≥7 mm: 1 point
4 mm & <7 cm: 2 points
≤4 mm: 3 points
How is the “L” in R.E.N.A.L, which stands for Location relative to polar lines, scored?
Entirely above upper or below lower polar lines: 1 point
Lesion crosses polar line: 2 points
50% of mass is across polar line, or mass crosses axial renal midline, or mass is entirely between polar lines: 3 points
What are the complexity scores for the R.E.N.A.L scoring system?
Low complexity: 4–6 points
Moderate complexity: 7–9 points
High complexity: 10–12 points
How are the points scored for Exophytic rate in the renal nephrometry system?
≥50% exophytic: 1 point
<50% exophytic: 2 points
Entirely endophytic: 3 points
What are the scoring criteria for Renal rim location?
Lateral: 1 point
Medial: 2 points
How is involvement of the Renal sinus scored?
Not involved: 1 point
Involved: 2 points
How are the Urinary collecting system parameters scored?
Not involved: 1 point
Dislocated/infiltrated: 2 points
What are the complexity scores based on the total points for renal nephrometry?
Low complexity: 6–7 points
Moderate complexity: 8-9 points
High complexity: 10–14 points
In the Simplified PADUA system, how is the Maximal tumor diameter scored?
≤4 cm: 0 points
4 cm & <7 cm: 2 points
≥7 cm: 4 points
What are the scoring criteria for the Simplified PADUA system based on complexity?
Low complexity: 0–3 points
Moderate complexity: 4–7 points
High complexity: ≥8 points
For patients with suspected renal malignancy undergoing partial nephrectomy, which approach is suggested when technically feasible and oncologically safe?
A minimally invasive approach (robotic-assisted or conventional laparoscopy) is suggested over an open approach.
For patients undergoing radical nephrectomy with suspected renal malignancy, which approach is recommended over open or robotic-assisted methods?
A conventional laparoscopic approach is recommended.
Between open partial nephrectomy, conventional laparoscopy, and robotic-assisted techniques, which one is generally associated with less blood loss, shorter hospitalization stay, and less severe postoperative complications?
Minimally invasive techniques (conventional laparoscopy or robotic-assisted partial nephrectomy) are generally associated with these benefits.
When is open partial nephrectomy deemed appropriate for complex small renal masses (SRM)?
Open partial nephrectomy is appropriate for complex SRM if the alternative is radical nephrectomy.
When performing a radical nephrectomy, why is the conventional laparoscopic approach favored over the robotic-assisted approach?
Due to the higher total cost, higher equity, and the lower surgical complexity of a radical nephrectomy (compared to a partial nephrectomy), conventional laparoscopic radical nephrectomy is strongly favored.
Do conventional laparoscopy and robotic-assisted partial nephrectomy differ in terms of oncological and functional outcomes?
There does not seem to be any clinically significant difference between conventional laparoscopy and robotic-assisted partial nephrectomy in terms of oncological and functional outcomes.
Which type of surgery for partial nephrectomy is potentially associated with a higher incidence of major bleed and shorter ischemia time, especially early in the robotic experience era?
Robotic-assisted surgery.
For radical nephrectomy, what key advantages do minimally invasive approaches offer over an open approach?
Minimally invasive approaches offer decreased hospitalization stay and fewer complications while providing similar oncological outcomes.
What are the two main techniques of percutaneous ablation for small renal masses (SRM)?
Cryoablation (tissue damage by freezing) and radio-frequency ablation (tissue damage by heat).
Based on retrospective studies, how do cryoablation and radio-frequency ablation compare in terms of oncological outcomes and adverse events?
Both yield similar oncological outcomes and adverse events.
What factors should influence the choice between cryoablation and radio-frequency ablation?
Availability, provider’s experience, and tumor-related factors (size, location, adjacent structures, etc.).
According to the panel, what procedure is recommended before percutaneous ablation of a renal tumor?
A renal tumor biopsy should be performed prior to ablation for histological confirmation.
For which tumor sizes are the majority of reported outcomes available concerning ablation techniques?
Tumors <3 cm in size.
How do 3-4 cm tumors compare to tumors <3 cm in terms of complications and local recurrence after treatment?
3-4 cm tumors have a higher likelihood of complications and local recurrence compared to <3 cm tumors.
Between cryoablation and radio-frequency ablation, which technique is suggested to have a lower cancer-specific mortality for tumors 3-4 cm based on some evidence?
Cryoablation.
Given a choice between cryoablation and radio-frequency ablation for tumors 3-4 cm, which technique seems reasonable to favor?
Cryoablation.
What are the primary factors that define oncological risk for patients under active surveillance?
Growth of tumor to >4 cm, consecutive growth rate >0.5 cm/year, progression to metastases, and patient’s choice.
What is the recommended imaging method when suspected tumor growth is observed on ultrasound?
: Patients with suspected tumor growth on ultrasound imaging should undergo cross-sectional imaging to confirm growth prior to intervention.
What is the average growth rate for a Small Renal Mass (SRM) during surveillance?
Typically 0.1–0.25 cm per year.
What was the average growth rate of tumors in patients who had metastatic progression on surveillance?
0.8 cm per year.
Which two registries have specific criteria for progression based on tumor growth?
The DISSRM registry (uses growth rate >0.5 cm per year) and the Renal Cell Carcinoma Consortium of Canada (doubling of calculated tumor volume within 12 months).
What are the challenges associated with growth rate assessments?
Comparisons might require different imaging modalities.
Growth may be exponential.
Intra- and inter-observer variability in tumor measurement.
Stochastic growth patterns in some tumors.
For what reasons might a renal mass biopsy be considered in a patient on active surveillance with concerning tumor growth?
A biopsy can be considered if it will change the management of the patient.
What are the risks associated with an increased tumor size?
Increased risk of harboring malignancy, risk of aggressive histology, risk of developing metastatic disease, and survival outcomes.
What criterion do the Renal Cell Carcinoma Consortium of Canada and the DISSRM registry consider for progression based on tumor size?
Tumor diameter >4 cm.
Why might patient age, frailty, and comorbidities be considered when deciding on delayed interventions?
These factors should be used to estimate the risk of mortality from competing medical conditions. In elderly, frail, or comorbid patients, the risks of intervention might outweigh the benefits.
What role should patient anxiety play in decision-making for intervention?
While patient anxiety should be factored into decision-making, it should not be the sole criterion. Clinicians should provide appropriate counseling, potentially including decision aids.
How did active surveillance for a renal mass impact depression and anxiety in patients, based on one study?
The study found that depression and anxiety were not adversely affected while on active surveillance for a renal mass and, in fact, improved with time.
What is the primary objective of active surveillance for small renal masses?
The objective of active surveillance is to delay treatment until evidence of disease progression.
Which imaging modality is suggested for routine abdominal check-ups for patients under active surveillance for suspected renal malignancy?
Abdominal ultrasound, especially when there is good visualization and agreement in size measurements between ultrasound and cross-sectional imaging.
In the event that tumor growth is suspected on surveillance ultrasound or the mass can’t be identified reliably, what step is recommended?
An abdominal cross-sectional imaging using CT or MRI is required for confirmation.
Why are chest X-rays included in most renal mass active surveillance protocols?
Though rare, patients on active surveillance may develop distant metastases. Chest X-rays help in early detection of these metastases.
What is the probability of asymptomatic patients with tumors <4 cm in size harboring pulmonary metastases?
Less than 1% as assessed by CT chest.
How often do the panel members suggest abdominal imaging during the first year of active surveillance?
Every 3-6 months for the first year and then every 6-12 months if the lesion remains stable.
What is the recommendation regarding the frequency of chest imaging for patients on active surveillance?
There’s no consensus. Recommendations varied from for-cause (52.6% of members) to once a year (47.4% of members).
Why is ultrasound suggested over CT or MRI for surveillance of small renal masses?
Ultrasound is cost-effective, avoids ionizing radiation, offers adequate assessment of growth, and is more readily accessible/available than CT and MRI.
What is recommended for patients with RCC post definitive treatment?
They should be followed with routine chest and abdominal imaging to rule out recurrence or progression to metastasis.
When should a patient be considered for a referral to a nephrologist post-definitive treatment?
When should a patient be considered for a referral to a nephrologist post-definitive treatment?
Who provides an in-depth guidance for the follow-up of patients with hereditary RCC?
The guideline by Lattouf et al.
What is the recurrence or metastasis rate post-surgery for patients with pT1a RCC?
5%.
5%.
Annual blood test (CBC, serum chemistries, LFT), annual chest X-ray, abdominal CT, MRI, or ultrasound at 24 and 60 months.
When is a contrast-enhanced abdominal CT scan/MRI recommended for patients treated with partial nephrectomy?
Optional at 3-12 months post-treatment to evaluate the residual baseline renal appearance.
How often is a contrast-enhanced abdominal CT scan/MRI recommended after thermal ablation?
At three, six, and 12 months post-treatment, then annually, along with annual bloodwork and chest X-ray.
Why might patients with postoperative chronic renal failure be referred to nephrology or their GP?
Due to a potentially higher risk of developing cardiovascular disorders.
