[980] Primary Small Cell Carcinoma of the Renal Pelvis: A Report of 11 Cases

Q Si, M Stanton, P Tamboli, BA Czerniak, CC Guo. University of Texas MD Anderson Cancer Center, Houston, TX

Background: Most small cell carcinomas (SCC) of the genitourinary tract arise from the urinary bladder and the prostate. Primary SCC of the renal pelvis is distinctively rare. Here we reported 11 cases of primary SCC arising in the renal pelvis.
Design: We searched our pathology file and identified 15 patients with SCC of the kidney. Four patients were excluded from the study, because they had a previous history of lung SCC and their renal SCC was considered a metastasis. The specimens included radical nephrectomy (n=10) and renal biopsy (n=1). Histologic slides were reviewed and clinical data was collected from the patients' medical records.
Results: The mean age of 11 patients at diagnosis was 57 years (range, 22-75 years). Seven patients were women and 4 were men. The most common presenting symptoms were flank pain (n=4) and hematuria (n=4). All the tumors were located in the renal pelvis with a mean size of 8.2 cm (range, 4.7-14.0 cm). In 8 cases, the tumors showed typical microscopic features of pure SCC, while in 3 cases they were associated with a high-grade urothelial carcinoma of the renal pelvis. The tumor cells were positive for cytokeratin (9/9), chromogranin (5/8) and synaptophysin (5/8). Lymphovascular invasion was present in 10 cases. Lymph node metastases were identified in all patients who underwent lymph node dissection (4/4). In 10 cases, extensive involvement of perinephric adipose tissue was present, and in 1 case only, the tumor was confined to the kidney. Nine patients died of disease at a mean of 13 months (range, 4-18 months), and 1 patient did not have follow-up information available. Interestingly, the patient with tumor confined to the kidney was alive without evidence of disease at 135 months after radical nephrectomy.
Conclusions: Primary SCC of the renal pelvis is a highly aggressive disease. Most patients present at an advanced stage with widespread metastases. Despite multimodal therapy, patients with an extensive disease have a dismal prognosis. Although the origin of SCC in the renal pelvis is unclear, the association with urothelial carcinoma in some cases suggests that it may evolve from the preexisting urothelial carcinoma.
Category: Genitourinary (including renal tumors)

Wednesday, March 24, 2010 9:30 AM

Poster Session V # 82, Wednesday Morning


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