2023 年 43 巻 9 号 p. 540-547
Trichoblastoma, a benign cutaneous adnexal tumor formed by follicular germinative cells, is frequently confused with basal cell carcinoma (BCC). Herein, we present a case of a 58-year-old male with a subcutaneous nodule measuring 5 cm in the mid-thoracic region, which had been present for 18 years. The patient was diagnosed with BCC with neurodifferentiation based on earlier biopsy and total resection. Following consultation, sweat-gland carcinoma with neuroendocrine differentiation was suspected; however, immunostaining revealed that the patient had trichoblastoma. We report each disease and discuss it with a literature review.