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

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.

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.

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.

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.