Evaluation of confocal laser scanning microscopy in histological classification and photodynamic therapy of low-risk basal cell carcinoma

Abstract

Abstract Background Confocal laser scanning microscopy (CLSM) is a noninvasive technique utilized for identification and analysis of skin malignancies. Several studies have applied CLSM in monitoring the treatment of basal cell carcinoma (BCC). Objectives To investigate the diagnostic value of CLSM in low-risk BCC and the evaluation of photodynamic therapy (PDT). Methods We diagnosed 149 patients with BCC using CLSM and histopathological examination. Based on histopathology, we summarized the classification of low-risk BCC along with imaging features observed through CLSM. Thirty-four patients with low-risk BCC underwent PDT treatment, and we used CLSM to evaluate its efficacy. Results Out of 149 BCCs examined by CLSM, 52 were diagnosed as the pigmented type, 87 as the nodular type and 10 as the superficial type. After histopathological examination of the 52 BCCs identified as pigmented by CLSM, 44 out of 52 were seen to be pigmented, 5 were nodular and 3 were superficial. The histopathology results were consistent with CLSM for the 87 nodular and 10 superficial BCCs. The distinguishing CLSM feature of nodular BCC was tissue fissures around the tumour, while the pigmented mass was the CLSM characteristic of the pigmented type. The simultaneous occurrence of inflammation and increased vasculature was characteristic of superficial BCC. The effective rate of PDT was 100%, and the cure rate was 68%. At the 12-month follow-up, the recurrence rate of PDT was 12%; 15% for nodular BCC, 10% for pigmented and 0% for superficial. Conclusions The tissue classification of CLSM for low-risk BCC was consistent with histopathology. CLSM can be used to monitor the ­efficacy of PDT for low-risk BCC.