renal tumors Flashcards
RCC is more common in men or women?
Peak incidence age?
Risk factors?
Associated conditions?
Men, 2x
6th decade
Tobacco, first degree family history, dialysis
VHL
What are the 5 types of RCC? What are the cells of origin?
Clear cell - 65%, proximal tubule
Papillary - 15%, distal convoluted tubule
Chromophobe - 5%, collecting duct
Collecting Duct - 1%, medullary collecting duct
Oncocytoma - 5%, collecting duct
Unclassified - 5%
Which subtype RCC has best prognosis? worst?
Best - Chromophobe
Worst - conventional, clear cell
What is the gene/chromosome defect in conventional/clear cell RCC?
VHL gene
Chromosome 3
What is the chromosome in papillary RCC?
7 and 17, and loss of chromosome y
With regards to mets, which has more common and which are more malignant?
Clear cell more common
Papillary more aggressive
What is birt hogg dube syndrome?
Lung cysts
RCC/oncocytoma
Hair follicle hamartoma
What is the imaging appearance of oncocytoma?
CT - well defined with sharp interface and central stellate scar
MRI - low T1, high T2 (RCC usually high T1), enhancement
Angiography - vascular renal tumor with dense tumor blush and spoke wheel appearance
What is renal medullary carcinoma? What is the association? Where is it located? What is the prognosis?
Variant of collecting duct carcinoma seen with sickle cell carcinoma
Dominant tumor in medulla, grows in an infiltrative pattern
Invades the renal sinus with caliectasis WITHOUT pelvicaliectasis
Poor prognosis
What is the staging classification system for renal tumors?
TNM
Is there a relationship between tumor size and mets?
Larger size - increase risk of mets
What type/shape of calcification suggests malignancy?
Central or thick mural calcification
Thin, peripheral, curvilinear - cyst
What are the 3 basic radiologic patterns of cystic renal cell carcinoma?
Unilocular cystic mass
Multiloculated cystic mass
Discrete mural nodule in a cystic nodule
What is the most common cause of perinephric hemorrhage in nonanticoagulated patients?
Renal tumor
What are the charateristic ct imaging features of:
Clear cell/conventional
Chromophobe
Papillary
heterogenous, hypervascular (60-100HU), central necrosis
Enhancement (less so than clear cell, 30-50HU), homogenous enhancement, usually peripheral enhancement, focal calcification
Enhancement (less so than clear cell, 30-50HU), homogenous enhancement, focal calcification
Which RCC subtype is more likely to be multifocal?
Which is more likely to have contralateral recurrence?
Papillary
Clear cell
What amount of houndsfield enhancement suggests papillary/chromophobe vs clear cell
What are the US features that help distinguish RCC?
What is the doppler cutoff suggested for diagnosis of vascular RCC?
Hypoechoic rim - if hyperechoic mass, helps distinguish from AML
Poorly defined margins - if hypoechoic
Thickened walls, +/- internal echoes if cystic
doppler shift of 2.5 MHz suggest carcinoma of inflammatory mass
What are the MR chracteristics of RCC?
Homogenous tumors are isointense with renal parenchyma, but will enhance
Hypovascular tumors are better detected with fat saturation techniques
What are the basic imaging findings seen in renal carcinoma?
May have calcification
Heterogenous mass
Diffuse margin with normal parenchyma
Enhances with intravascular contrast media
What is a cytoreductive nephrectomy?
Surgical resection of kidney with known metastatic disease for palliative reasons
What is removed in a radical nephrectomy? When is nephron sparing surgery undertaken?
Kidney, regional LN, paraaortic-left sided tumors, adrenal glands
Everything in the perirenal space
T1 tumors, less than 4 cm in diameter
When is radiofrequency ablation or cryoablation used?
T1a and T1b tumors
When is angiography used in treatment of RCC?
Presurgical embolization to stop operative blood loss
Treatment on nonsurgical patients, such as with gelfoam
EtOH can occlude the renal artery
What are the pathways of metastatic spread in RCC?
Hematogenous - renal vein -> lungs
Lymphatic - regional lymph nodes in the perinephric space -> thoracic duct
When do most tumor recurrences of RCC occur?
Within 2 years of ablation
lung/bone mets 1-2years
tumor bed recurrence 1-3 years
Where is the most common site of mets?
Lung - bone - tumor site - brain - liver
What is a wilms tumor? What age group gets them?
Nephroblastoma arising from metanephric blastema
50%
What are the associations with Wilms tumor?
Sporadic aniridia - usually bilateral
Hemihypertrophy
Pseudohermaphroditism, glomerulonephritis, wilms tumors (DRASH syndrome)
Beckwidth-Wiedemann - macroglossia, omphalocele, adrenal cytomegaly, visceromegaly, microcephaly, malformed ears, GU abnormalities
What chromosome is associated with wilms/aniridia?
11
What are the contents of wilms tumor?
Epithelial (striated muscle, adipose, cartilage, bone)
Blastemal
Stromal elements
What is the US appearance of wilms tumor?
Solid, hyper/hypoechoic mass with welldefined margins
May have intratumoral hypoechoic areas representing hemorrhage or necrosis
Can have dystrophic calcification
What is the CT appearance of wilms tumor?
Hypoenhancing mass with varying heterogeneity based on amount of hemorrhage/necrosis
Where are the common sites of mets with wilms tumor?
Lung and liver
What is the median age of presentation with Rhabdoid tumor
What is the association?
11months
Second primary malignancy of the CNS - astrocytoma, ependymoma PNET
What is nephroblastomatosis? IS it malignant?
Group of pathologic entities characterized by persistent nephrogenic blastema
Not malignant, but associated with wilms
What are the imaging findings with nephroblastomatosis?
Diffuse - enlarged kidney, parenchymal nodules
Multinodular - microscopic nodules
Hypoechoic usually
SUBCAPSULAR is key finding to separate from between polycystic renal disease and lymphoma
Poor enhancement, scalloping of the kidney
What is mesoblastic nephroma?
Fetal mesenchymal hamartoma present at birth
Comprised of interlacing sheets of fibromatous cells
What is the appearance of mesoblastic nephroma?
Large tumor >6cm with a whorled appearance resembling leiomyoma of uterus
No capsule, finger like extensions
Nontender abdominal mass
Usually homogeneously echoic, occasionally with necrosis or hemorrhage
What is the treatment of mesonephric nephroma
surgical excision
Which sex gets sporadic AML more often?
Females, age 40yo
What is the association with bilateral AML?
Tuberous sclerosis
What is the renal involvement of LAM?
Smooth muscle hamartomas (AML) along lymphatic system
XR - lucent mass
What are the US findings of AML? CT?
Highly echogenic mass depending on fat content
Fat is the key finding, though there can be lipid poor AML
Calcification is rare in AML, so this would suggest fatty RCC
Is there an increased risk of RCC with AML?
yes, but small
Formed bone in the kidney in an older patient suggests what?
Primary renal osteosarcoma
Where are leiomyomas found in the kidney? is there a sex predominance?
Lower pole
Female
Where are renal hemangiomas usually located?
Apex
What is a juxtaglomerular tumor? What are the symptoms? Where is it located?
Tumor of juxtaglomerular apparatus
essential hypertension
peripherally
not malignant
What are the imaging findings of JGA tumors?
US - echogenic mass due to abundant vascular channels
CT - isodense enhancement
Arteriography - splaying of renal vessels by a hypovascular mass
Which lymphoma has renal involvement more commonly?
NHL, usually bilateral involvement
Burkitts and AIDS related subtypes
What is the appearance of renal lymphoma?
Multiple masses - most common
Solitary/diffuse involvement
Direct extension from adjacent disease
Which way is the proximal/distal ureter displaced in lymphoma?
Proximal - lateral due to paraaortic LN
Distal - medial due to external iliac chain
What is the US of renal lymphoma? ct?
Hypoechoic due to homogenous nature
CT - Homogenous round mass with hypoenhancement relative to the surrounding parenchyma
What is the associated nephropathy with renal leukemia?
Urate
What are the common primary sources of kidney mets?
Lung, breast, colon, melanoma
What is a small indeterminate renal mass?
Small,
