Hidradenocarcinoma/Porocarcinoma

Case 360   Oct 2011 (P. McKee)  M 67 nodule on thrunk 

Difficult case, limited views.  Zone of malignant epithelium with clear cell change, squamous differentiation and comedo-necrosis.  Ductal differentiation was present (confirmed by EMA) but not shown. 

Case 1155  26.11.14  (H. Diwan)  M 68 pinna 

Scanning power looked poroma-like.  Closer inspection revealed too much cellular pleomorphism.  Basaloid areas resembling BCC with retraction artefact. 

Case 1458   26.1.16  (U. Sundram)  F 77 friable lesion on neck 

Deeply infiltrative clear cell tumour with rather monotonous cytology.  Surface ulceration.  Wide range of diagnoses suggested.  Diagnosis clarified by IH:  CK +ve;  melanoma markers, synaptophysin, chromogranin, CD99 (T+B cells) all –ve. 

Case 2622   24.7.20  (R. Carr) M 80 cheek – hidradenoacarcinoma in situ. 

Looked like a metastasis with squamoid differentiation and central cystic degeneration.  Ki67↑↑; EMA++; CK7 ++.  EVG showed no elastic entrapment, indicating that the lesion was not invasive.  This is a primary adnexal tumour in the dermis, not a met.  Discussion on P53/P16 null patterns. 

Case 4463 28.2.24 (H. Diwan) F 76 right groin mass