Fig. 30

Surgical treatment of melanoma in situ affecting the right thumbnail. Longitudinal melanonychia on the right thumbnail of a 42-year-old man that is narrow and without marked irregularity of pigmentation (a). Dermoscopy however revealed broad irregular lines (b), suggesting the diagnosis of melanoma in situ, which was confirmed histopathologically upon excision. Resection of the entire nail apparatus including the nail bed and nail matrix was performed along with the periosteum of the distal phalanx, but the digital bone was preserved. Artificial dermis was applied on the tissue defect after surgery. After formation of granulation tissue, full-thickness skin grafting was performed. One year after the surgery, the appearance (c) and function (d) of the thumb are excellent