非露光部に生じた熱傷瘢痕上基底細胞癌の1例

A Case of Basal Cell Carcinoma on a Burn Scar in a Non-exposed Area

はじめに

　熱傷瘢痕に続発する腫瘍は有棘細胞癌（squamous cell carcinoma：以下，SCC）がよく知られており，受傷から長期間経過してから発症することが多い。一方で基底細胞癌（basal cell carcinoma：以下，BCC）の発症はまれであり，本邦では渉猟し得た限り19例の報告に留まる。なかでも，非露光部には5例しか生じていない。今回，熱傷瘢痕癌としてはまれなBCCが非露光部に受傷後短期間で生じた1例を経験したので報告する。

　An 80-year-old woman noted skin pigmentary degeneration of part of a burn that she had incurred 2 years earlier, and she visited a local clinic for an examination. The physical examination revealed a 30×40-mm erythema on the patient’s back, and a biopsy of the site was performed at the clinic. The biopsy results revealed basal cell carcinoma （BCC）, and the patient was referred to our hospital. We excised the lesion with a surgical margin of 3 mm and used sutures for the wound closure. Although squamous cell carcinoma commonly develops from burn scars （which often contract long after the trauma）, the development of BCC after a burn is rare. Twenty such cases have been reported in Japan, including a self-described case; among them, only five cases occurred in a non-burn-exposed part. BCC on a burn scar may occur within a short period even from mild burns. It is important to treat burn scars in elderly patients with symptoms such as ulcer while considering the possibility of BCC regardless of the period after the injury.