Intraoperative frozen section-guided excision versus standard surgical excision in basal cell carcinoma: A prospective randomized clinical study

Abstract

Background: Basal cell carcinoma (BCC) is the predominant cutaneous malignancy globally. Determining the optimal balance between complete tumour clearance and healthy tissue preservation, particularly in cosmetically sensitive facial regions, remains a major clinical challenge. Objective: To compare intraoperative frozen section-guided excision (FSGE) with standard wide local excision (SWE) using fixed clinical margins in patients with primary facial basal cell carcinoma, focusing on margin clearance, defect area, patient-reported scar outcomes, operative time, and 12-month local recurrence. Patients and Methods: A prospective, randomized comparative clinical trial enrolled 120 patients diagnosed with primary, non-recurrent facial BCC (≤ 20 mm). Participants were allocated 1:1 into Group A (FSGE, n=60 initial 2 mm visual margin expanded intraoperatively based on cryostat histology) or Group B (SWE, n=60 uniform 4 mm fixed margin with standard FFPE processing). Key endpoints included primary complete margin clearance rate, post-excision defect surface area (cm²), POSAS cosmetic scores at 6 months, total operative duration, and 12-month recurrence rate. Clinical case documentations and perioperative steps were verified photographically. Results: First-pass margin clearance was achieved in 58 of 60 patients (96.7%) in the FSGE group and 50 of 60 (83.3%) in the SWE group, a difference of 13.3 percentage points (95% CI, 2.9–23.8; p = 0.030). Secondary re-excision was needed in 0/60 versus 10/60 (p=0.001). Mean defect area was 1.82 ± 0.45 cm² with FSGE and 2.48 ± 0.62 cm² with SWE (26.6% smaller; p<0.001). The 6-month POSAS patient score was lower (better) with FSGE (14.2 ± 3.1 vs 21.5 ± 4.8; p<0.001). Mean procedure time was longer with FSGE (72.4 ± 14.2 vs 38.6 ± 8.1 min; p<0.001). Local recurrence at 12 months occurred in 0/60 versus 2/60 patients (p=0.50). Conclusion: Compared with fixed-margin excision, FSGE was associated with a higher first-pass margin clearance rate, smaller surgical defects, fewer secondary operations, and better patient-reported scar scores, but longer operative times. The difference in recurrence was not significant, and longer follow-up is needed.