Does lymph node dissection during nephroureterectomy affect oncological outcomes in upper tract urothelial carcinoma patients without suspicious lymph node metastasis on preoperative imaging studies?

This study aimed to investigate the effects of lymph node dissection (LND) on upper tract urothelial carcinoma (UTUC) without suspicious lymph node (LN) metastasis on preoperative imaging studies.

From 1998 to 2012, 418 UTUC patients without suspicious LN metastasis on preoperative imaging studies were included. Patients were divided into two groups according to the performance of LND. The effects of LND on oncological outcomes were assessed after adjusting other variables. The mean follow-up duration was 69 months.

Among the 132 patients who underwent LND, LN metastasis was pathologically identified in 16 patients (12.1 %). The median number of resected LNs for patients who underwent LND was 7. On multivariate analysis, the number of resected LNs and pathologic T stage was significant predictors of LN metastasis. The 5-year recurrence-free survival was 76.4 % for patients without LND and 65.4 % for patients with LND (p = 0.126). In addition, there was no difference in 5-year overall survival between the 2 groups (without LND; 71.7 % vs. with LND; 72.1 %, p = 0.756). Multivariate analysis showed that pathologic T stage, tumor grade, and lymphovascular invasion were risk factors for recurrence. Age at surgery, tumor size, pathologic T stage, tumor grade, and lymphovascular invasion were significantly associated with overall survival. However, performance of LND was not associated with recurrence and survival.

LND could be selectively performed in patients with clinically LN-negative UTUC based on patient/tumor characteristics and operative findings although sufficient LNs should be removed if LND is to be performed.