Predictive factors for ipsilateral recurrence after nephron-sparing surgery in renal cell carcinoma.

BACKGROUND: Ipsilateral recurrence after nephron-sparing surgery (NSS) is rare, and little is known about its specific determinants.
OBJECTIVE: To determine clinical or pathologic features associated with ipsilateral recurrence after NSS performed for renal cell carcinoma (RCC). DESIGN, SETTING, AND PARTICIPANTS: We analysed 809 NSS procedures performed at eight academic institutions for sporadic RCCs retrospectively. MEASUREMENTS: Age, gender, indication, tumour bilaterality, tumour size, tumour location, TNM stage, Fuhrman grade, histologic subtype, and presence of positive surgical margins (PSMs) were assessed as predictors for recurrence in univariate and multivariate analysis by using a Cox proportional hazards regression model. RESULTS AND LIMITATIONS: Among 809 NSS procedures with a median follow-up of 27 (1-252) mo, 26 ipsilateral recurrences (3.2%) occurred at a median time of 27 (14.5-38.2) mo. In univariate analysis, the following variables were significantly associated with recurrence: pT3a stage (p=0.0489), imperative indication (p<0.01), tumour bilaterality (p<0.01), tumour size >4cm (p<0.01), Fuhrman grade III or IV (p=0.0185), and PSM (p<0.01). In multivariate analysis, tumour bilaterality, tumour size >4cm, and presence of PSM remained independent predictive factors for RCC ipsilateral recurrence. Hazard ratios (HR) were 6.31, 4.57, and 11.5 for tumour bilaterality, tumour size >4cm, and PSM status, respectively. The main limitations of this study included its retrospective nature and a short follow-up.
CONCLUSIONS: RCC ipsilateral recurrence risk after NSS is significantly associated with tumour size >4cm, tumour bilaterality (synchronous or asynchronous), and PSM. Careful follow-up should be advised in patients presenting with such characteristics.