Frozen Sections for Margins During Partial Nephrectomy Do Not Influence Recurrence Rates

Introduction: Frozen sections (FS) are routinely employed to assess margin status during partial nephrectomy (PN) for clinically localized renal cell carcinoma (CLRCC); however, their oncologic benefit remains unclear. There have been no studies investigating the long-term impact of FS on local or metastatic recurrence. We wished to determine whether the utilization of FS for this purpose during PN influenced recurrence rates.

Materials and methods: We performed a retrospective review of 1090 patients with (n = 172) and without (n = 918) FS during open and robotic PN between 2006 and 2016 for CLRCC at a single tertiary care institution. Standard follow-up protocols were employed, with imaging used to guide subsequent biopsy for confirmation. Univariate and multivariate competing-risk regression analysis predicting the association of FS status and clinicodemographic characteristics with recurrence, with adjustment for all-cause mortality, were performed. Administrative data were reviewed to calculate costs of FS.

Results: Forty-five out of 1090 (4.13%) patients had recurrence. There was no difference in the cumulative incidence of recurrence between patients with and without FS (χ² = 0.001, p = 0.97). On multivariable competing risk analysis, FS was not associated with recurrence (hazard ratio [HR], 1.56; 95% confidence interval [CI], 0.65-3.76). However, tumor grade (g3-4 vs 1-2: HR, 2.45; 95% CI, 1.16-5.14) and stage (>pT2 vs pT1a: HR, 2.86; 95% CI, 1.13-7.26) were associated with recurrence. The average direct charge per patient undergoing FS was $902.

Conclusions: Intraoperative FS for margins during PN did not predict decreased recurrence rates in a single-institution high-volume center. Given the lack of associated benefit, and the added cost, the utilization of FS during PN should be limited.