A 64-year-old man comes to the office due to several episodes of intermittent hematuria over the past 2 months. He has had no abdominal pain, burning on urination, or fever but has lost 4.5 kg (10 lb) since the onset of symptoms. The patient has smoked a pack of cigarettes daily for 30 years. Vital signs are within normal limits. The abdomen is soft, nontender, and nondistended. Ultrasound reveals a mass in the right kidney. A subsequent abdominal CT scan confirms the presence of a large right renal mass with evidence of necrosis. The patient undergoes a right total nephrectomy. The specimen is shown below. This patient's lesion most likely originated from which of the following portions of the kidney?

Question

A 64-year-old man comes to the office due to several episodes of intermittent hematuria over the past 2 months.  He has had no abdominal pain, burning on urination, or fever but has lost 4.5 kg (10 lb) since the onset of symptoms.  The patient has smoked a pack of cigarettes daily for 30 years.  Vital signs are within normal limits.  The abdomen is soft, nontender, and nondistended.  Ultrasound reveals a mass in the right kidney.  A subsequent abdominal CT scan confirms the presence of a large right renal mass with evidence of necrosis.  The patient undergoes a right total nephrectomy.  The specimen is shown below.  This patient's lesion most likely originated from which of the following portions of the kidney?

Quizplus · Accepted Answer

Eductional Objective: Clear cell carcinoma is the most common type of renal cell carcinoma and originates from the epithelial cells of the proximal renal tubules.  Gross pathology typically demonstrates a sphere-like mass composed of golden-yellow cells (due to high lipid content) with areas of necrosis and hemorrhage.

A 64-Year-Old Man Comes to the Office Due to Several