W1 Renal Masses & Cancer (Joey)

Question 1

Which fascia encapsulates both the kidney and the adrenal gland?

Which just surrounds the kidney?

What is stage 4 renal cancer?

Answer 1

Gerota’s Fascia (aka the Anterior Renal Fascia):

Gerota’s Fascia is the fascial connective tissue layer that
surrounds and encapsulated both they kidneys & the adrenal
glands

the renal capsule (aka fibrous renal capsule), which just surrounds the kidney itself

Extension of a renal mass BEYOND the GF or INTO the ipsilateral ADRENAL GLAND is considered Stage 4 renal cancer

Question 2

Clinically, what size renal mass is concerning?

What size is definitely cancer?

What else could it be?

Where do most cancers start?

What type of cancer would be in the renal pelvis?

Answer 2

Clinically however we start getting most interested in renal masses that are > 4 cm (or some renal masses < 4 cm that look very abnormal)

>7cm is most likely cancer

Is the mass solid, or cystic appearing? If cystic does it look complex?

Location: Is the mass starting in the renal CORTEX, or elsewhere?

the majority of renal cell carcinomas start in the renal CORTEX

A renal mass appearing to start from the renal PELVIS should raise suspicion for Transitional cell carcinoma (TCC)

Question 3

Surveillance of small renal masses (SRM)

Answer 3

The detection of renal masses, especially incidental small renal masses (renal masses < 4 cm) has increased over the past few decades d/t increased use of imaging tests (US, CT, MRI) performed for unrelated (not related to s/sx of renal disease) indications, and these incidental renal masses are often asymptomatic

Despite the increased incidence of such masses, mortality rates from concerning masses like RCC have remained stable (or even decreased) in developed countries…

Question 4

How to confirm if a cystic mass is malignant?
It has a similar density to ______
Cystic renal mass has a HU score of ______
A score of over ______ is more likely to be solid

Answer 4

A “Cystic Renal Mass” on imaging is a mass that appears to have “similar density to water”

“Hounsfield Units” where the higher value of Hus = more likely to be solid or vascularised.

A true simple (non-septated) cystic renal mass typically has a HU score of ≤ 10

A cystic renal mass w/ HU score >20 is usually at least a highly proteinaceous fluid-filled or blood-filled mass, point: higher HU >20, the > likely to actually be solid

About 10% of cystic renal masses end up being RCC

Bosnian Classification helps radiologist categorise each cystic renal mass as non surgical or surgical.

Question 5

Notable autosomal dominated inherited cystic renal syndromes (3)
And what are they associated with —
Polycystic kidney disease is a/w?

Tuberous sclerosis is a/w with? 2
Von Hippel-Linda disease is a/w?

Answer 5

CKD is a/w AD polycystic kidney disease

Tuberous sclerosis is a/w angio-myo-lipomas and RCC

⭐️von Hippel-Linda’s disease is a/w RCC.

The gene mutation is VHL

AD = autosomal dominant

Question 6

What about other renal mass sizes that aren’t small?

Answer 6

● “Intermediate Renal Mass”: Renal Masses (>4 cm but < 7 cm)
—There are more suspicious and if decision is made not to resect these immediately then they warrant closer monitoring (frequency variable), however if they appear to be solid in nature, heterogenous, or complex cystic, then these should likely be excised

● “Large Renal Mass”: (> 7 cm)
—These are more concerning and much more likely to be malignant in nature, or if they are benign may impact renal function from a pure mass effect / obstructive standpoint

Question 7

Which size solid renal mass is likely to be RCC?

Answer 7

> 4cm

Question 8

Renal cell carcinoma
Definition — arises from which tissue, where?
Which gene association?
Which histologic finding in 75% of all cases?

Answer 8

Malignant growth of renal cells, often arising from the renal
epithelial tissue of the renal cortex (so arises along the nephron)

50% of RCC cases are a/w mutations in the VHL tumour suppressor gene

Most common histologic form of RCC is clear cell RCC which accounts for 75% of all RCC cases

Question 9

Risk factors for renal cell carcinoma — main one

Answer 9

Smoking & Toxin Exposures (similar to TCC)

VHL inherited mutation a/w RCC are more likely to be sporadic

VHL gene mutations are a/w earlier presentation and bilateral disease

Question 10

Renal Cell Carcinoma Presentation
What is the classic triad?
What might you see on labs in pts w/ advanced disease?

Answer 10

The classic triad of presentation for RCC has been:

⭐️Hematuria
⭐️Flank Pain
⭐️Palpable Abdominal Mass

however in more recent decades RCC actually tends to be more often initially suspected/identified when performing imaging for another indication (aka by the modern term “incidental renal mass”

RCCs may also inappropriately generate hormones (including erythropoietin), or other signalling molecules (like interleukin 6, prostaglandins, TNF-alpha) or promote excessive production of active Vitamin D3 (aka calcitriol) so on labs in pts w/ more advanced dz you may see findings like

⭐️anemia OR erythrocytosis and
⭐️hypercalcemia

Question 11

Renal cell carcinoma
What do you need for diagnosis ?
What else will you see on imaging? 2 characteristic findings…

Answer 11

—CBC and CMP for assessment of erythrocytosis
—baseline renal fxn
—serum calcium status
—and +/- INR for pre-operative assessments

⭐️For definitive diagnosis of RCC, you need BIOPSY!⭐️
collected via nephrectomy

—on u/s the mass does not meet the criteria for a simple cyst

—on CT, the features of RCC include thickened irregular walls or septa and enhancement w/ IV contrast

Question 12

Renal cell carcinoma treatment
What is 1st line gold standard?
What is a hallmark of stage 3 disease?

Answer 12

⭐️1st line gold standard is a radical nephrectomy ⭐️

One of the hallmark features of of stage 3 RCC is a phenomenon called “IVC Invasion” which is invasion of an RCC tumor into the inferior vena cava.

This is tumour thrombus

Patients will need nephrectomy + tumour thrombectomy

Pts will be started on anticoagulants

Question 13

Just an FYI

Question 14

RCC: Post treatment surveillance

Answer 14

q3-6 mo CT A/P and CT Chest for the first 1 year, then spaced out from there based on staging algorithm.

Question 15

RCC: Characteristics of stage 1-4 and survival rates

Answer 15

Stage 1 (tumor <7 cm and limited to the kidney): typically
—5-Year Survival is typically >90%

Stage 2 (tumor is >7 cm and limited to the kidney):
—5-Year Survival is typically 75-90%

Stage 3: many stage 3s but tumour
—renal vein, artery, ICV invasion
—has not invaded ipsilateral adrenal gland
—5 year survival in pts who undergo nephrectomy 60-70%

Stage 4:
—into ipsilateral adrenal, beyond GF, mets
—5 year survival <10-20%

Question 16

Renal cell carcinoma commonly metastasises to? 3
Think about it like this, this is cancer of the KIDNEY, it’s going to spread to other big organs….

Answer 16

1. Heart
2. Lungs
3. Brain

Question 17

RCC:
What are some post treatment conditions a patient may have to live with / require tx for?

Answer 17

—increased risk of developing AKI and CKD b/c only 1 kidney
—increased risk of developing adrenal insufficiency
—may need hormone replacement
—may need lifelong steroids to replace normal activity of cortisol

Question 18

⭐️Which Pediatric renal mass do you need to know about?
Presents with?

Answer 18

⭐️Nephroblastoma : Wilms Tumour

—malaise
—HTN
—palpable abdominal mass
—hematuria
—fever

most common renal tumour in children <15y/o in the US

Wilms Tumor is a (nearly exclusively pediatric) renal tumor that develops from abnormal persistence & proliferation of metanephric mesoderm tissue cells (one of the embryological structures that gives rise to the kidney → proliferation leads to development of a tumor made of cells that are in a “pre-development of the normal tubular / glomerular differentiation” stage)

Question 19

Wilms tumour
Most common presenting symptom
First diagnostic test?
2nd diagnostic test if suspicious?
Which cancer is rare in pedis?
Definitive diagnosis?

Answer 19

Almost always presents symptomatically as an abdominal mass or swelling w/o other specific sx

typically abdominal ultrasound is used to start given peds population

If Abd US concerning for WT, then often move to CT A/P (RMP) vs MRI to further evaluate

R/o suspicion for other type of renal tumors (benign, RCC - but RCC RARE in pre-adolescent children)

⭐️need biopsy!!

Question 20

Wilms Tumour
Treatment — what is often given?
Surveillance

Answer 20

Surgical Resection:
—Radical vs Partial Nephrx +/- rads +/- chemo standard of care, however highly variable b/o +/- invasion, mets
—⭐️Chemo (is often given to WT patients post-nephrectomy):
—Highly dependent on staging, however is commonly combo tx

—often via q 3 - 12 mo surveillance imaging, regular assessment of renal fnx

Prognosis IS dependent on staging & histology

Question 21

❗️[must know]
Renal mass and renal cell carcinoma take away
—what is the classic triad presentation?
—nowadays, how are masses discovered?
—closely monitor which size?
—which size raises suspicion?
—which size is highly concerning for malignancy?
—what are 2 concerning characteristics of complex cysts?
—Which gene mutation is a/w 50% of RCCs?
—what is the classic treatment?
—what is the MC ped mass? Which age? Which treatments (2)

Answer 21

Renal Masses & RCC:
● The classic triad of presentation for RCC has been: “Hematuria, Flank Pain, & Palpable Abdominal Mass,”
however in more recent decades RCC actually tends to be more often initially identified / suspected when performing imaging for another indication (aka the “incidental renal mass”)
○ In countries where regular access to imaging is less common, the traditional “triad” of RCC still stands

● Renal masses < 4 cm can often be safely closely monitored for changes in size or characteristics rather than being immediately resected, however very abnl appearing SRMs may warrant resection

● Not all renal masses are malignant or RCC, however renal masses > 4 cms should raise significant suspicion
and warrant workup, while renal masses > 7 cm are likely to be malignant

● Complex cystic renal masses with rim enhancing walls or septations regardless of size are highly correlated with cystic RCC and often warrant excision

● Mutations in VHL gene are present in > 50% of RCCs on pathology

● Classic treatment for RCC is a radical nephrectomy, however this comes with significant side effects (CKD, etc)
and smaller renal masses may be treated with a partial nephrectomy or ablation therapy

● Not all malignant masses in the kidney are even of renal origin (though most are), as other cancers may metastasize to the kidneys

Wilms Tumor:
● Wilms Tumor: Most common renal tumor in children, 95% tend to present < age 10

○ Most important aspect of workup, tx, prognosis for pts as a non-onc PA is getting pt to ped onc ASAP

○ These pts are typically treated with surgical resection followed by combination chemotherapy