IN VIVO REFLECTANCE CONFOCAL MICROSCOPY CRITERIA TO MONITOR TREATMENT RESPONSE FOR BIOPSY-PROVEN BASAL CELL CARCINOMA

Document Type

Conference Proceeding

Publication Date

5-8-2023

Publication Title

Lasers Surg Med

Abstract

Background: Reflectance confocal microscopy (RCM) criteria for in vivo diagnosis of basal cell carcinoma (BCC) have been established. These include the presence of streaming in the epidermis, dermal tumor islands and/or dark silhouettes, peripheral palisading, peritumoral clefts, highly refractive peritumoral fibrosis, increased and dilated vessels, and inflammatory cells. These criteria have been validated for untreated BCCs, and studies have reported high sensitivity for BCC diagnosis using these RCM criteria. Of note, the majority of clinical studies investigating efficacy of novel treatments for BCC require biopsy-proven BCC as a study inclusion criterion. When monitoring treatment response, some of the RCM BCC features may be impacted by the treatment itself. The objective of this study was to prospectively image biopsy-proven BCC with RCM at baseline and during the posttreatment follow up to determine clearance and identify associated RCM features. Study Design/Materials and Method: Ten subjects with biopsy-proven BCC were enrolled and completed this IRB approved study. Clinical examination, dermoscopy, and RCM imaging were performed at baseline, before treatment, and at approximately 12 weeks posttreatment of BCC lesions with a 1064 nm Nd-YAG Laser. RCM features of BCC were documented and compared to clinical and histologic determination of treatment response. Results: For the lesions that had no residual BCC histologically, RCM features that exhibited statistically significant changes at follow up compared to baseline included absence of: hyperreflective tumor islands, dark silhouettes, peripheral palisading, peritumoral clefting, and dermal inflammatory cells. Changes in streaming, fibrosis, and increased and dilated vasculature did not reach significance. Conclusion: The presence of RCM streaming, fibrosis, and dilated vessels at BCC sites that were otherwise clear posttreatment histologically, could be secondary to scar formation as a part of the healing process. It is likely to observe these during RCM imaging of biopsy-proven BCC at baseline (resulting from healing of biopsy and remaining BCC compressing the overlying epidermis) and posttreatment (resulting from treatment induced healing process and/or presence of residual BCC compressing the overlying epidermis). As such, these three RCM BCC features, although reported to have high association with BCC diagnosis, should be interpreted with caution when used for monitoring treatment response for biopsy-proven BCCs. The results of this pilot study are significant considering an ongoing increased number of BCC clinical trials that require clinical and imaging-based determination for the need of subsequent treatments during the trial, and because of the possible role of artificial intelligence for RCM interpretation in the future. Large-scale studies are needed to further validate these findings.

Volume

55

First Page

S56

Find It @ Sladen

Share

COinS