Recurrence Rate of Melanoma in Situ when Treated with Serial Disk Staged Excision: A Case Series.

Background: Cutaneous melanoma is one of the fastest rising cancer diagnoses in recent years. Melanoma in situ (MIS) constitutes a large proportion of all diagnosed melanomas. While surgical excision is considered the standard of therapy, the literature is not clear on which surgical technique minimizes local recurrence. A common technique is serial staged excision (SSE), in which a series of mapped excisions are made according to histopathological examination of tissue. Previously published recurrence rates for SSE ranges from 0-12%, over a range of 4.7-97 months of mean follow-up.

Objective: To investigate the recurrence rate of MIS when excised using a serial disk staged excision technique with tissue marked at 12 O'clock for mapping, rush permanent processing and histologic examination, 3-suture tagging for subsequent stages, and "breadloafing" microscopic analysis. Additionally, to determine the relationship between initial lesion size and subsequent stages of excision required for clearance, and final surgical margin.

Methods: Single-institution retrospective chart review of 29 biopsy confirmed MIS lesions treated with our variant of SSE. Statistical analysis via independent t-tests.

Results: No recurrences were observed with mean follow-up of 31.5 months (SD 13.9), over range of 12-58 months. Mean surgical margin of 13.1 mm (SD 5.9). A trend towards larger surgical margin was seen with increasing pre-operative lesion size.

Conclusion: This method of SSE for treatment of MIS is comparable in efficacy to other SSE techniques, and may offer physicians a relatively simple, efficacious, and accessible alternative to wide local excision and Mohs micrographic surgery.