Diagnostic utility of imprint cytology in assessing surgical margins during laparoscopic partial nephrectomy

Partial nephrectomy (PN) is the preferred treatment for cT1 and cT2 renal tumors, with the goal of preserving renal function while maintaining oncological outcomes. Achieving negative surgical margins is crucial for minimizing recurrence risk. This prospective study included 113 patients with 117 renal tumors who underwent PN. IC samples were collected by pressing glass slides onto the specimen surface (Sample A) and from Tru-cut biopsies (Sample B). All slides were processed with hematoxylin-eosin staining and evaluated by a senior pathologist. Cytological findings were classified as positive, negative, or indeterminate. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were assessed relative to the final pathological results. Positive surgical margins (PSM) were observed in five patients. In one case, the surgical margin could not be evaluated and was therefore excluded from the IC evaluation. Of the 116 cytology A samples, 101 were negative, 7 were positive and 8 were indeterminate. The sensitivity was 100 %, specificity was 98 %, PPV was 71.4 %, and NPV was 100 %. No recurrence was observed in patients with PSM during a median follow-up of 16.9 months. The present study demonstrated that IC is a simple, rapid, and cost-effective method for predicting surgical margins and can be a useful as a rule-out test during intraoperative decision-making.