Reflectance Confocal Microscopy–Optical Coherence Tomography‐Guided Laser Ablation of Low‐Risk Basal Cell Carcinoma: A Long‐Term Prospective Follow‐Up Study

OBJECTIVES: The primary objective was to evaluate the long-term recurrence rate following RCM-OCT-guided laser ablation of basal cell carcinomas (BCCs). The secondary objective was to assess patient-reported outcomes, including willingness to undergo the treatment again, scar acceptability, and adverse effects. METHODS: A prospective cohort study evaluated 104 patients with 148 BCCs (2017-2021). Low risk BCC subtypes and with tumor depth of ≤ 300 µm were determined using RCM-OCT, and eligible lesions underwent same-day Er:YAG laser ablation with immediate post-treatment imaging to confirm clearance. Patients underwent clinical and RCM-OCT or RCM surveillance at 6 and 12 months and annually thereafter to assess recurrence. A patient-reported questionnaire was conducted in 2023. RESULTS: Fifty-eight lesions (39.2%) in 39 patients met the criteria for laser ablation. Most lesions were located on the trunk (29/58, 50.0%), with median tumor depth and lesion size of 200 µm and 9.8 mm, respectively. Immediate post-ablation RCM-OCT demonstrated imaging-defined complete clearance after a single session in 53/58 lesions (91.4%). Residual tumors (5/58, 8.6%) were successfully treated during the same visit. Fifty-four of 58 lesions (93.1%) had at least 6 months of follow-up (median 32 months; min/max 8-70). One recurrence occurred at 53 months and was successfully retreated, corresponding to 1.04 recurrences per 100 person-years of follow-up. The patient-reported questionnaire response rate was 79.5% (31/39). Overall, 96.8% (30/31) reported acceptable scar appearance, 83.9% (26/31) were likely to choose laser ablation again (Score 1-2 of 5), and 9.7% (3/31) reported mild, transient side effects. CONCLUSIONS: RCM-OCT-guided Er:YAG laser ablation offers a "one-stop" treatment approach for selected low-risk BCCs, demonstrating low long-term recurrence rates and high patient satisfaction.