Contribution of positive renal vein margin to relapse risk in renal cell cancer

Abstract

16110 Background: Positive margins in surgically resected solid tumors usually connote higher local relapse rate. There is some evidence this may not be so in renal cell cancer (RCC), and the significance of involvement of the renal vein margin (RVM) is especially difficult to interpret. We reviewed tumor registry data to assess the relapse rate in such scenarios. Methods: After IRB approval, the tumor registry of the Memphis VA hospital was queried for patients with RCC, stage T3b/ T3c, N(any), M0 treated by nephrectomy. Charts were reviewed for known prognostic variables including TNM stage, Fuhrman grade, and involvement of the adrenal gland or perinephric fat. Margin status was assessed, with RVM involvement distinguished from other margins. Outcomes recorded were site and date of recurrence, and date of last contact or death. Local recurrence (LR) and distant recurrence (DR) rates and mean time to recurrence (TTR) were calculated according to RVM status. Survival and TTR were calculated from date of nephrectomy. Results: Of 313 kidney cancer patients, 16 met the above criteria. Mean follow-up was 3.7 years. Two patients had no follow up. No patients had LR. Four died after DR (mean survival 1.3 yr); 5 died without relapse (mean survival 5.1 yrs); 4 are alive without relapse (mean followup 7.7 yrs) and 1 is alive with disease after 7 yrs. Three patients with positive RVM all had DR with mean TTR 2.96 years (range 0.05 to 6.34); two have died (survivals 3 and 0.2 yrs) while the other is alive at 7 yrs. Of the other 11 patients with adequate followup, 3 (27%) had DR with mean TTR 1.0 years (range 0.47 to 1.48); two died at 1 yr, one was lost to follow up after 2 yrs. One patient with a positive ureter margin was lost to follow up. No patients underwent adjuvant treatment. Conclusions: Our data are consistent with the previous evidence that positive margins in RCC may not connote a high rate of local relapse. However, positive RVM was associated with a high rate of distant recurrence. This indicates a need to include such patients in clinical trials of newly emerging systemic therapies instead of focusing on delivery of local therapy. No significant financial relationships to disclose.