Renal Syndromes and Tidbits Flashcards
Periungual fibromas
Flesh-colored papules near the nail bed
Tuberous sclerosis
Fibrofolliculomas
Small white or flesh-colored papules on face, neck, back or upper trunk
Birt-Hogg-Dubé Syndrome
Trichilemmomas
Wart-like flesh colored papules typically on face or dorsum of hands and feet
PTEN Hamartoma (Cowden) Syndreom
Cutaneous Leiomyoma
Small pink0purple papules in same location as hair follicles
Often painful
HLRCC –> Hereditary leiomyomatous RCC
Papillomas
Hard, smooth flesh-colored papules usually on face, lips, mouth, hands and feet
PTEN Hamartoma (Cowden) Syndrome
(also has trichilemmomas, glans macules, and keratosis)
On workup of a renal mass…
If UA has proteinuria, get quantitative measure of urine protein
- Assign a CKD stage urine proteinuria level and GFR
- If <45 mL/min GFR before treatment, send to nephrology
- If after treatment you expect GFR will be <30, send to nephrology
For renal masses, consider biopsy when:
- Suspicion that mass is infectious, inflammatory, AML, lymphoma, or a tumor metastasis to kidney
- Nephrectomy candidate who chooses surveillance, ablation or embolization
- To confirm diagnosis in metastatic patient who will not have cytoreductive nephrectomy before systemic chemotherapy
HMB-45 stain of renal tumor
- Metastatic melanoma
- AML
List of benign renal masses
- Simple renal cyst (most common)
- Papillary adenoma (most common SOLID benign)
- Pseudotumor
- AML
- Oncocytoma
- Juxtaglomerular tumor
- Multilocular cystic nephroma
- Mesoblastic nephroma
RCC TNM staging
Cancers that met to kidneys
- Lymphoma/leukemia
- Lung
- Breast
Less common: stomach, colon, cervix, melanoma
Renal pseudotumors
- Look like solid masses on some imaging, but are normal parenchyma
Examples: column of bertin, fetal lobulation, dromedary hump, hilar lip or uncus, nodular compensatory hypertrophy
CT/MRI with contrast or DMSA renal scan to tell apart
- On DMSA scan, pseudotumors will have normal uptake but true tumors will have decreased isotope uptake
Dromedary hump
- A focal bulge at the id-lateral kidney thought to be from downward pressure from spleen or liver during development
- More common on left
- A pseudotumor
Genetic counseling in renal cancer recommended in the following patients:
- Dx less than or equal to 46yo
- Multifocal or bilateral renal masses
- Tumor pathology suggests genetic syndrome (ex: mix of RCC and oncocytoma –> BHG)
- Personal history suggests genetic syndrome
- Family history suggests genetic syndrome
von Hippel Lindau (gene and type)
VHL
Clear cell RCC
BAP1 Syndrome (gene and type)
BAP1
Clear cell RCC
CHEK2 Syndrome (gene and type)
CHEK2
Clear cell RCC
Chromosome 3 translocation syndrome (gene and type)
Chromosome 3
Clear cell RCC
PTEN Hamartoma (Cowden) Syndrome (gene and type)
PTEN
Clear Cell RCC
Hereditary Papillary RCC Type I (gene and type)
MET
Papillary RCC Type I
Hereditary Leiomyomatosis RCC (gene and type)
FH
Papillary RCC Type 2
Aggressive –> surveillance not recommended even if tumors are small
Birt-Hogg Dubé (BHD) (gene and type)
FLCN (on 17)
RCC mixed with oncocytoma, oncocytoma alone, chromophobe RCC alone, clear cell rarely
Succinate dehydrogenase (SDH) deficiency RCC (gene and type)
SDH subunits B, C and D
Various types of RCC
Aggressive - no surveillance even for small tumors
Tuberous sclerosis (gene and type)
TSC1, TSC2
Various RCC, AML
Birt-Hogg-Dubé Syndrome
(presentation, cancer type, gene)
Skin fibrofolliculomas after age 20, air-filled pulmonary cysts, spontaneous pneumothorax, renal tumors
25% develop renal tumors –> most bilateral and multiple per kidney
- clear cell, chromophobe, oncocytoma, mix of oncocytoma and RCC
BHD is AD - FLCN on 17
PTEN Hamartoma (Cowden) Syndrome
Mutation in PTEN gene
RCC develops in 35% of cases (usually ccRCC)
Associated with RCC, breast cancer, endometrial cancer, thyroid cancer, glans macula, skin lesions (papillomas, trichilemmomas, keratosis), macrocephaly and autism
Tuberous Sclerosis
Triad seen in 30%: mental retardation, seizures, adenoma sebaceum
AD causes by TSC1 (on 9) or TSC2 (on 16) mutation
Hamartomas - retina, brain, skin, kidney (AML), lung, heart (cardiac rhabdomyomas)
Uro manifestations: renal cysts, AML, RCC
- 60% with AML, most multiple
- 2% RCC of any type
Adenoma sebaceum, ash-leaf spots, shagreen patches, ungual fibromas
von Hippel Lindau
AD, mutation of VHL gene on 3p
Non-uro: cerebellar hemangioblastoma, spinal HAB, retinal angioma
Uro: renal cysts (75%), ccRCC (50%), pheo (15%), epididymal cystadenoma (10%), epididymal cysts (7%)
VHL –> mutation 3p –> ccRCC is most common
RCC bilateral and multifocal, early (<40yo)
All renal cysts (even simple) have malignant potential (OK for surveillance until 3cm)
Papillary Adenoma
Benign
- Usually incidental finding during autopsy
- <5mm, but microscopically looks the same as low grade papillary RCC
- Adenomas arise from proximal tubule
Oncocytoma
Benign
Arises from collecting duct
Composed of oncocytes –> cells with eosinophilic granular cytoplasm
Most common in 40-60 yo M
Can’t be distinguished from RCC on imaging –> tx as RCC
“Spoke wheel” pattern on arteriogram, but nonspecific
Grossly: tan mass with a central scar and fibrous capsule
Micro: nests of polygonal cells with granular eosinophilic cytoplasm
RCC may coexist with oncocytoma
Tx of choice = surgical excision
Juxtaglomerular Tumor
Rare but benign
Renin-secreting tumor, arises from JG apparatus
Usually <3cm in diameter
Presents young (<25yo), diastolic HTN, headaches, increased renin, hyperaldosteronism with hypokalemia
Treatment = nephron sparing excision
Angiomyolipoma (AML)
Benign
Will stain positive for HMB-45
Occurs in 40-60yF, 60% of TS patients
Most AML patients do NOT have TS
On CT, it enhances: -20 to -80 HFU (fat), homogenous, not calcified or cystic
Everolimus = approved to shrink AML in TS patients not having surgery
When >4cm or sxs, can do embolization, ablation or excision
Sarcomatoid elements in RCC
May be present in any subtype of RCC
Indicated high-grade tumor and worse prognosis
Trichloroethylene
A chlorinated solvent
Increases risk of RCC with exposure
Clear cell (conventional) RCC
Most common primary renal malignancy in adults
Arises from proximal tubule
Associated with loss of 3p, the short arm of chromosome 3
Most common type of RCC in patients with vHL
Adenoma Sebaceum
Pink or red papules on cheek bones or nasolabial folds
Tuberous sclerosis
Chromophobe RCC Classification
Arises from collecting duct
Associated with multiple chromosomal losses
Similar to oncocytoma under the microscope
Chromophil (papillary) RCC classification
Classic pathologic feature = papillary architecture
Type I = basophilic cytoplasm, low grade
Type II = eosinophilic cytoplasm, high grade, worse prognosis
Arises from proximal tubule
Associated with polysomy (of 7 and 17), MET mutations, loss of Y chromosome
Papillary RCC = most common renal cancer in patients with chronic renal failure on dialysis
Collecting Duct Carcinoma Classification
AKA Bellini duct carcinoma
Rare, highly malignant, arises from collecting duct usually in renal medulla or papilla
40% present with mets
Micro: hobnail cells lining tubular spaces
5-year survival = rare
Renal medullary carcinoma
RARE form of collecting duct carcinoma
Young adults of African ancestry with sickle cell trait
Typical age = 10-39
Tumor rarely confined to kidney, rarely respond to chemo/rads
Poor prognosis; mean survival after nephrectomy = 15 weeks
Only tumor with racial predilection
Paraneoplastic syndromes associated with RCC
10-20% will have paraneoplastic syndrome
- Elevated ESR, alk phos
- Weight loss, cachexia
- Fever
- Anemia
- HTN - from renin produced by tumor
- Hypercalcemia - from a PTH-like substance produced by the tumor
- Stauffer’s syndrome = hepatic dysfunction; a reversible hepatitis associated with RCC that has NOT metastasized to the liver
- Polycythemia - from erythropoietin produced by tumor
Risk of RCC met based on size at presentation
Both lymphatic and hematogenous spread
A solitary met is present in 1% of cases –> if there are mets, they are multiple
<3cm - 4% risk
3-4 cm - 7% risk
4-7 cm - 16% risk
7-10 cm - 30%
10-15 cm - 41%
>15 cm - 51% risk
RCC metastatic sites (most to least common)
Lung
Bone (most common in spine)
Regional LN
Liver
Adrenal
Contralateral kidney
Brain
