A case report of a rare adnexal tumour: aggressive digital papillary adenocarcinoma

We report the case of a 78-year-old Caucasian gentleman who presented with a painful swelling in the nail bed of the right middle finger. Following amputation of the right middle phalanx histopathology confirmed aggressive digital papillary adenocarcinoma (ADPA). Further surgical treatment was offered but declined. Approximately 17 months later, the patient was found to have pulmonary metastasis. ADPA is a rare neoplasm of the eccrine sweat glands, which commonly presents as a slow-growing mass between the nail bed and distal interphalangeal joint. The disease is classically aggressive with a 14% chance of metastatic spread. The chance of recurrence is 50% with no or sub-optimal treatment, which reduces to 5% following removal with adequate resection margins. This case shows a prolonged period of disease-free survival, but highlights the need for thorough and aggressive management in cases of ADPA as well as frequent and long-term follow-up.