microcystic adnexal carcinoma

(redirected from sclerosing sweat duct carcinoma)

microcystic adnexal carcinoma (MAC)

a form of adnexal tumor that often appears on the face as a yellow, indurated plaque with ill-defined margins. The patient experiences fullness, pain, burning, anesthesia, or paresthesia in the area of the lesion.

microcystic adnexal carcinoma

A rare (circa 300 cases in the world literature) malignant skin appendage tumour, usually typed as a low-grade sweat gland carcinoma which occurs on the head and neck, and especially on the central face. It is locally aggressive and invades bone, muscle, blood vessels, cartilage, and nerves, but rarely metastasises. It presents as a clinical lesion averaging 3 cm2, but leaves an average post-surgical defect of 18 cm2, due to occult extension.

Epidemiology
Adults (median age 50; range 10 to 90).

DiffDx
Syringoma, desmoplastic trichoepithelioma, adenosuamous carcinoma, trichoadenoma, morphoeic BCC, metastatic breast carcinoma, small cell carcinoma.

Prognosis
It is locally aggressive, but rarely metastasises.

Aetiology
20–50% of patients have a history of therapeutic radiation with a 30-year average latency; UV light has also been implicated.
 
DiffDx
Desmoplastic trichoepithelioma, syringoma, trichoadenoma.
References in periodicals archive ?
Finally, malignant neoplasms that may mimic dermatofibroma include dermatofibrosarcoma protuberans, giant cell tumor of the skin (a low-grade sarcoma) (10), nodular melanoma, basal cell carcinoma, and sclerosing sweat duct carcinoma (11).
Differential diagnosis of dermatofibroma Benign lesions Malignant lesions Cyst Basal cell carcinoma Hypertrophic scar Dermatofibrosarcoma protuberans Neurilemmoma (or schwannoma) Giant cell tumor of the skin Neurofibroma Nodular melanoma Piloleiomyoma Sclerosing sweat duct carcinoma Tophus Erythema elevatum diutinum
52] Myoepithelial cells have not been found in porocarcinomas, sclerosing sweat duct carcinomas, extramammary Paget disease, malignant mixed tumors, or adenosquamous carcinomas,[51-53] whereas they have been occasionally detected in mucinous carcinomas, apocrine adenocarcinomas,[51,52] and adenoid cystic carcinomas.