Tumors of the kidney

What is the clinical significance of renal hamartoma?

• usually an incidental finding at autopsy; no malignant properties

Which disease is/can be assoc. w/ angiolopoma?

• these are present in 25-50% of pts w/tuberous sclerosis, a disease characterized by lesions of the cerebral cortex that produce epilepsy and mental retardation as well as a variety of skin abnormalities

What is oncocytoma?

• epithelial tumor thought to arise from intercalated cells of collecting ducts; not uncommon

• GROSS: tan or mahogany brown, relatively homogeneous and usually well-encapsulated; up to 12cm

• MICRO: large eosinophilic cells w/ small rounded, benign-appearing nuclei; (w/EM--eosinophilic cells have lost of mitochondria)

• px: benign

What is the difference between cortical adenoma and renal cell carcinoma?

• cortical adenoma (renal papillary adenoma): benign, usually papillary; commonly found at autopsy; histo. criteria--do not differ from low-grade papillary renal cell adenocarcinoma and share some immunohistochemical and cytogenic features (trisomies 7 &17) w/ papillary CAs; px--no real reliable marker for benignity so usually treat small tumors as early CAs

• renal cell carcinoma: see table for complete info; malignant; may be either clear cell (nonpapillary) carcinoma, papillary carcinoma, or chromophobe renal carinoma

Know the incidence, sex distribution, possible causes and clinical manifestations of renal cell carcinoma

• 85% of renal CA in adults; 30,000 new cases/yr; 12,000 deaths/yr; usually in 6th or 7th decade of life

• male > female (2-3:1)

• possible causes: smoking; obesity (esp. in females); HTN; unopposed estrogen tx; exposure to asbestos, petroleum products, and heavy metals; increased incidence in pts w/chronic renal failure, acquired cystic disease, and tuberous sclerosis; assoc. w/Von Hippel-Lindau syndrome; some rare familial forms

• clinical manifestations: 3 classic signs--costovertebral pain, palpable mass, and hematuria, this triad of sx only appears in about 10% of cases. the most reliable sx is hematuria but may be intermittent and microscopic so may not be obvious until tumor is large. other sx may be fever, malaise, weakness, and weight loss

Know the cytogenetic aspects of clear cell, papillary and chromophobe carcinoma

• these are discussed in the table

Know that in asymptomatic hematuria in elderly pts the dx of renal cell carcinoma should be seriously considered

• okie dok!

Know the prognosis of renal cell carcinoma

• average 5 yr survival is about 45% and up to 70% in absence of distant metastases

• px of chromophobe renal carcinoma is excellent compared w/ clear cell and papillary Cas

Know the incidence, possible causes and px of urothelial carcinomas

• 5-10% of 1º renal tumors; range from benign papillomas to frank papillary carcinomas (benign are difficult to distinguish from low-grade papillary CAs); usually small when discovered b/c of locationfragmentation causes noticeable hematuria; may be multifocal; in 50%, have preexisting or concomitant bladder urothelial tumor

• possible causes: increased incidence in pts w/ analgesic nephropathy

• px: 50-70% 5 yr survival for low-grade superficial lesions to 10% w/high-grade infiltrating tumors

Category: Pathology Notes