Ecase #11-B

David True, M.D.

August 27-31, 2001

A 34 yo female is seen in clinic with c/o acute onset R flank pain and gross hematuria beginning the prior evening. The pain is described as severe, non-radiating and limiting her ability to walk. She denies fever, sweats, nausea/vomiting, or dysuria. She has had an infrequent h/o UTI's, no past h/o kidney stones. She has a h/o Grave's disease and is s/p I 131 thyroid ablation 10 years previously, now stable on thryoid replacement. There is no h/o STD's and she is in a stable monogamous relationship using oral contraceptives. No recent analgesic use. She does recall one previous incident of gross hematuria occurring 6 mos previously, not associated with pain, which occurred after a prolonged bike ride while training for a triathlon. F/u UA at that time was negative.

PE shows the patient to be afebrile; BP 150/90, HR 110

Pt in acute pain. R flank tender to palpation/percussion. No mass notable on abdominal exam. No notable organomegaly; Bowel tones audible. Pelvic and rectal exams negative.

UA with 3+ hematuria; >100 RBC's; Neg for WBC's/red cell casts; CBC is normal

What is your differential diagnosis?

What tests would you pursue?

Differential diagnosis could include nephrolithiasis, renal tumor, trauma, polycystic kidney disease, renal TB, glomerular or tubular disease. Acute pyelonephritis/perinephic abcess would be less likely given the lack of fever, dysuria, leukocytosis, and pyuria.

Direct microscopic exam did not reveal red cell/tubular casts making glomerular or tubular disease less likely.

Spiral CT was obtained and revealed an 8cm R renal mass, obliterating the R adrenal gland and most of the R kidney; no lymphadenopathy or hepatic lesions were noted; the L kidney appeared normal.

What is your plan for further evaluation?

Surgical consult was obtained. The extent of involvement of the tumor suggested the need for nephrectomy with prior angiography to identify extension of the tumor into the vena cava. No vena caval involvement was noted. R radical nephrectomy was performed revealing no evidence of lymph node involvement.

Subsequent pathology revealed a renal cell carcinoma, which was then subclassified into an oncocytoma.

What are the clinical characteristics of Renal Carcinoma?

Renal carcinoma is usually discovered via asymptomatic hematuria. A triad of gross hematuria, flank pain, and palpable abdominal mass is well known but less common (10% of cases). Presentation is usually in the 7^th and 8^th decade of life and twice as common in men as women. Up to 30% of patients have distant metastases at the time of presentation and these can occur to virtually any organ site. Paraneoplastic syndromes can occur and include erthrocytosis, hypercalcemia, hepatic dysfunction, and amyloidosis.

Histologic cell type is important with regard to prognosis. Renal cell carcinoma ranges in aggressiveness from the clear cell tumor (most aggressive), to the oncocytoma (generally considered a benign tumor). Intermediate grades include the chromophilic and chromophobic cell types (of higher and lower metastatic potential, respectively).75-80% of renal carcinomas are of the clear cell variety.Tumors confined  within the renal capsule are resected for cure. Staging is based on the anatomical extent and histological features of the tumor. Unfortunately, no chemotherapeutic or radiation treatments have proven effective in treating this tumor. 50% of patients do not survive beyond 5 years; of those with metastases, only 5-10% survive beyond 5 years.

Reference

Motzer, R.J. et al.; "Renal-Cell Carcinoma", NEJM; Sept. 19, 1996; 335(12):865