A case report of a rare adnexal tumour: aggressive digital papillary adenocarcinoma
A 78-year-old Caucasian gentleman presented with a painful 2 cm irregular swelling in the nail bed of the distal phalanx of the right middle finger, with brown discolouration of the nail bed. The swelling in the digit had been present for ∼30 years, which had begun following a fracture of the terminal phalanx and had gradually increased in size over the preceding 6 months. There was no axillary or cervical lymphadenopathy and the patient was fit and well.\nClinically a differential diagnosis of an aggressive adenocarcinoma was suspected, but this was not supported by multiple radiological investigations. CT and MRI of the lesion showed a vascular destructive lesion that was causing severe erosion of the distal interphalangeal bone (Figs and , respectively). A plain chest radiograph at that time showed no pulmonary metastasis.\nAs the radiological investigations had shown that the distal phalanx was not viable and a lack of proximal invasion, it was felt appropriate to perform an amputation at the level of middle to distal third of the middle phalanx. Such an amputation was aimed at being curative, in addition to providing a definite diagnosis, maintaining function and allowing for primary closure.\nThe patient underwent an amputation of the middle phalanx of the right middle finger. Histopathology of the specimen showed a high mitotic grade lesion with a small focus of lymphovascular invasion, diagnostic of ADPA (Fig. ). The tumour was 0.7 mm from the nearest resection margin. The high rates of recurrence and metastasis were explained to the patient, who declined further surgical treatment.\nSeventeen months following initial presentation, the patient developed a mass in the right axilla. In addition, subsequent plain chest radiograph (Fig. ) and CT of the thorax showed multiple pulmonary metastasis. An axillary clearance was performed and one of the ten nodes confirmed metastatic disease. Shortly after this, the patient suffered an intracranial haemorrhage into the right internal capsule. Over the last 2 years the patient has remained only mildly short of breath due to his pulmonary metastasis and was improving neurologically. At a recent review, the patient showed features of deterioration due to the pulmonary metastasis.