[Conservative parenchymal surgery in kidney neoplasms].

Objectives: To analyze retrospectively a series of 60 nephron sparing surgeries (NSS) in patients presenting with renal masses.

Material And Methods: The clinical histories of 59 patients undergoing NSS between january 1978 and december 1997 were reviewed. 40 were males, the mean age 54.4 years (range 17-77 years). 10 (17%) had bilateral synchronous tumors, 15 (25%) had a solitary kidney and 3 a renal insufficiency. In 25 patients NSS was obligatory, while in 34 it was elective. 30 (50%) of the renal masses had been diagnosed incidentally. Overall, 49 kidneys underwent an enucleation and 11 a partial nephrectomy.

Results: The histopathological exam revealed 43 (71.6%) renal cell carcinomas (RCC), 2 (3.4%) urothelial carcinomas, 6 (10.2%) oncocytomas, 7 (11.6%) angiomyolipomas and 2 (3.4%) multilocular cystic nephromas. Among the RCC, 8 had < or = 3 cm, 22 between 3.1-5 cm, 10 between 5.1-8 cm and 3 more than 8 cm. 31 (72.1%) were well encapsulated and only 2 (4.6%) invaded the nearby parenchyma. 7 (16.2%) were pT1, 34 (79%) pT2 and 2 (4.6%) pT3. 39 (90.3%) were G1 or G2, and only 4 (9.3%) were G3. Two patients (3.3%) died perioperatively, both from the obligatory group. 3 (6.8%) of the patients with malignant tumors progressed and died, all with CCR and from the obligatory surgery group. Another 3 patients of this group developed local recurrences, but were rescued with iterative surgery (conservative in 1); 2 of these patients had sporadic CCR, another a von Hippel Lindau disease. None of the 34 patients who underwent elective NSS progressed, nor recurred locally and all are alive and disease free; only 14 (56%) of the 25 patients operated on by necessity survived, although 6 of them died of causes not related with the kidney tumor. The cancer specific survival at 58.3 months of follow-up (range 5-187 months) is 86.8% for the whole series, 100% for the elective NSS group and 68.7% for the obligatory NSS group. 19 (31.6%) patients developed complications, 14 among the obligatory group; two died (hemorrhage and sepsis). 3 patients presented acute renal failure, but none required dialysis; presently 4 (6.7%) patients have poor renal function and 1 requires dialysis.

Conclusion: NSS affords good control of renal carcinoma; in the cases operated on electively, the 100% cause specific survival yielded by NSS supports the use of conservative surgery in patients with well delimited tumors and normal contralateral kidney.