Cutaneous metastasis from gastric glomus tumour

A 58-year-old man presented with a 4-month history of a rapidly enlarging asymptomatic tumour on the scalp vertex. Six years earlier, the patient had undergone subtotal gastrectomy for a presumed gastrointestinal stromal tumour (GIST). The tumour extended to the peritoneal surfaces, and foci of vascular invasion were also seen. No adjuvant treatment was given. Owing to diagnostic difficulties with the scalp tumour, a comparison was made with the previous gastric neoplasm. Both had features consistent with glomus tumour, which suggested a revised diagnosis of primary malignant gastric glomus tumour with subsequent cutaneous metastasis to the scalp some years later. This case highlights the features of glomus tumours and is a reminder that although rare, glomus tumours can be malignant and have the potential to metastasize. To our knowledge, this is the only reported case of a primary gastric glomus tumour with secondary metastasis to the skin.