Small Cell Carcinoma of the Renal Pelvis: A Case Report and Review of the Literature

Extrapulmonary small cell carcinoma occurs in nearly all organs except the central nervous system and the liver. We are presenting a case of renal small cell carcinoma (SCC) with two unique characters. A 75-year-old patient was evaluated for back pain with no other complaints. Magnetic Resonance (MR) imaging of the abdomen revealed homogeneous tumor in the left renal pelvis extending beyond the kidney. Metastatic workup was negative. A left nephroureterectomy was performed. Histopathology and immunohistochemistry revealed a small cell carcinoma of the renal pelvis. The patient declined adjuvant therapy and died 2 months after surgery due to unrelated causes. After comprehensive worldwide literature search, we found 13 cases of SCC of the renal pelvis, including the current case. The mean age was 61.6 years (37-83), with a M : F ratio of 1 : 1.8. The average duration of symptoms was 71.4 days (21-168). Gross hematuria was the most common symptom (69.2%) followed by pain (61.5%). Adjuvant chemotherapy was provided to 4 patients (30.7%), and neoadjuvant to 1 patient. The median survival of patients who did and did not receive chemotherapy was 5.5 months (3-8) and 6 months (2-31), respectively, P < .50. In conclusion, renal SCC (both parenchymal and pelvic SCC) is a rapidly fatal disease with a median survival of ≤8 months.