MSS08 Presentation Time: 4:20 PM

Introduction Objectives

Basal cell carcinoma(BCC) is the most common malignancy of the Caucasian population. Dermoscopy is a diagnostic method that provides the bridge between clinical and pathological examination. Surface skin High Dose Rate (HDR) brachytherapy is an organ sparing treatment method used for non-surgical candidates in contemporary management of skin cancers. Literature lacks data reporting observations of dermoscopic patterns of non-melanoma skin cancers (NMSC) undergoing HDR brachytherapy.

Materials and Methods

Single center prospective study was conducted. Twenty three patients with high risk BCC's of facial region were treated with contact, 3D planned HDR brachytherapy with 9 fractions of 5Gy, 3 times a week. Custom made polyacrylamide surface moulds were used. Clinical and dermoscopic images were obtained before treatment and before every fraction and 6 months after treatment. 603 macroscopic and dermoscopic photographs were obtained. In every macroscopic picture 12 clinical features typical for BCC's were analyzed Dermoscopic images were searched for 61 dermoscopic neoplastic features and 31 dermoscopic non-neoplastic features. In total database of 21526 observations was analyzed by two independent dermoscopists using current diagnostic criteria.

Results

Univariate logistic regression showed decreasing number of clinical and pathological features with each fraction of brachytherapy. Correlation was more expressed for features typical for BCC. Older patients showed more pronounced response to treatment. After 6 months number of clinical and dermoscopic patterns typical for BCC as well as number of non neoplastic dermoscopic features is reduced, presumably due to formation of scar (Figure 1).

Conclusions

HDR brachytherapy decreases number of clinical and dermoscopic Basal Cell Carcinoma features. Effect is more pronounced in older patients. Medium time observation shows that effect is persistent after 6 months.