Positive surgical margin appears to have negligible impact on survival of renal cell carcinomas treated by nephron-sparing surgery

Abstract

Background: The occurrence of positive surgical margins (PSMs) after partial nephrectomy (PN) is rare, and little is known about their natural history.

Objective: To identify predictive factors of cancer recurrence and related death in patients having a PSM following PN.

Design, setting, and participants: Some 111 patients with a PSM were identified from a multicentre retrospective survey and were compared with 664 negative surgical margin (NSM) patients. A second cohort of NSM patients was created by matching NSM to PSM for indication, tumour size, and tumour grade.

Measurements: PSM and NSM patients were compared using student t tests and chi-square tests on independent samples. A Cox proportional hazards regression model was used to test the independent effects of clinical and pathologic variables on survival.

Results and limitations: Mean age at diagnosis was 61+/-12.5 yr. Mean tumour size was 3.5+/-2 cm. Imperative indications accounted for 39% (43 of 111) of the cases. Some 18 patients (16%) underwent a second surgery (partial or total nephrectomy). With a mean follow-up of 37 mo, 11 patients (10%) had recurrences and 12 patients (11%) died, including 6 patients (5.4%) who died of cancer progression. Some 91% (10 of 11) of the patients who had recurrences and 83% of the patients (10 of 12) who died belonged to the group with imperative surgical indications. Rates of recurrence-free survival, of cancer-specific survival, and of overall survival were the same among NSM patients and PSM patients. The multivariable Cox model showed that the two variables that could predict recurrence were the indication (p=0.017) and tumour location (p=0.02). No other variable, including PSM status, had any effect on recurrence. None of the studied parameters had any effect on the rate of cancer-specific survival.

Conclusions: PSM status occurs more frequently in cases in which surgery is imperative and is associated with an increased risk of recurrence, but PSM status does not appear to influence cancer-specific survival. Additional follow-up is needed.