Renal Cell Carcinoma: The Daily PANCE Blueprint
A 62-year-old man with a 40-pack-year smoking history has three months of painless gross hematuria, a dull ache in his left flank, and 15 pounds of unintentional weight loss. On examination there is a palpable left flank mass and a new left-sided varicocele that does not decompress when he lies down. Laboratory studies show hemoglobin 17.8 g/dL and calcium 11.4 mg/dL with a normal parathyroid hormone level. CT of the abdomen shows an enhancing 7-cm solid mass in the left kidney. Which of the following is the most likely diagnosis?
A. Urothelial (transitional cell) carcinoma of the bladder
B. Renal cell carcinoma
C. Angiomyolipoma
D. Autosomal dominant polycystic kidney disease
E. Renal abscess
Answer and topic summary
The answer is B. Renal cell carcinoma
Painless hematuria, flank pain, and a palpable flank mass is the classic triad of renal cell carcinoma — and the exam favorite is that the full triad appears in only about 10% of patients, so it usually signals advanced disease rather than an early catch. Two details here seal it. The new left varicocele that does not decompress when supine is a tumor thrombus or mass obstructing the left renal vein, into which the left gonadal vein drains — anatomy that explains why this sign is left-sided. And RCC is a great paraneoplastic mimic: polycythemia from ectopic erythropoietin (his hemoglobin of 17.8) and hypercalcemia from PTH-related peptide with a suppressed PTH (his calcium of 11.4), plus Stauffer syndrome, a reversible nonmetastatic hepatic dysfunction. Most cases are clear cell carcinoma arising from proximal tubular epithelium, and smoking is the leading modifiable risk factor, alongside obesity, hypertension, acquired cystic disease in dialysis patients, and von Hippel-Lindau disease. Diagnosis is by contrast CT, and biopsy is generally NOT required — an enhancing solid renal mass is taken to the operating room. Treatment is partial or radical nephrectomy; RCC is famously resistant to conventional chemotherapy and radiation, so advanced disease is treated with targeted agents and immunotherapy. The distractors are separable: urothelial carcinoma also causes painless hematuria in an older smoker but arises in the collecting system or bladder rather than as an enhancing parenchymal mass; an angiomyolipoma contains macroscopic fat on CT and is associated with tuberous sclerosis; polycystic kidney disease enlarges both kidneys with innumerable cysts; and a renal abscess is a febrile, acutely ill patient with pyuria.
View blueprint lesson
Smarty PANCE Content Blueprint Review:
Covered under ⇒ PANCE Blueprint Renal System ⇒ ⇒
