Syringocystadenocarcinoma papilliferum at unusual site: inherent lesional histologic polymorphism is the pathognomon.

The benign precursor usually antedates the malignancy by many years, as a non-progressive verrucous lesion; and when congenital, there is a frequent association with naevus sebaceous. In older people, the presence of solitary cutaneous adenocarcinoma leads to clinical consideration of a metastatic versus primary cancer; systematic morphologic analysis, will usually resolve the issue, as illustrated in the present tumour, which occurred in a 62-year-old male, in the axilla, where syringocystadenocarcinoma papilliferum is practically unknown. As described by the patient, a bead like, 1.0 cm axillary swelling, had been self-discovered and this lesion had excoriated and attained a size of 3.5 cm in 6 months. The clinical differentials included malignant change in a pre-existing adnexal neoplasm and metastatic malignancy in a superfi cially located axillary lymph node. The histology showed a villiform superfi cial portion, in continuity with ‘ducts’ bearing the ‘in situ’ component of the tumour and the deep, infi ltrating adenocarcinoma – Images in...