Elective nephron sparing surgery for renal cell carcinoma larger than 4 cm

Elective nephron sparing surgery is established as an alternative to radical nephrectomy for renal cell carcinoma if tumors are small (4 cm or less, stage T1a). We compared outcomes in patients with renal cell carcinoma 4 cm or less (small) vs more than 4 cm (large) who were treated with nephron sparing surgery.

Between 1979 and 2006, 618 patients underwent elective nephron sparing surgery at our institution. Of these patients 474 (76.7%) had renal cell carcinoma, which was 4 cm or less in 372 (78.5%) and more than 4 cm in 102 (21.5%). Followup was 4.7 (range 0.1 to 23.9) years for small and 4.7 (range 0.1 to 24.1) years for large tumors. Cancer specific survival and local recurrence free survival were estimated.

The estimated cancer specific survival rate at 5 years was 97.9% and 95.8%, and at 10 years it was 94.9% and 95.8% for small and large tumors, respectively (log rank p = 0.583). The survival rate free of local recurrence at 5 years was 98.5% and 98.3%, and at 10 years it was 93.9% and 98.3% for small and large tumors, respectively (log rank p = 0.282). In contrast to tumor size, stage 3 was associated with a significant higher risk of tumor related death.

Elective nephron sparing surgery is oncologically safe in select patients with localized renal cell carcinoma more than 4 cm. In our series the selection criterion for choosing elective nephron sparing surgery rather than radical nephrectomy over the years has consistently been safe surgical resectability rather than tumor size. However, there is a correlation between tumor size and unfavorable pathological tumor characteristics, which prompts caution when choosing elective nephron sparing surgery for all large tumors.