Microcystic adnexal carcinoma: report of rare cases

Abstract

Microcystic adnexal carcinoma (MAC) is a rare, locally aggressive malignant neoplasm that derives from cutaneous eccrine/apocrine glands. MAC is classified as an eccrine/apocrine gland tumor and usually occurs in the skin. Here, we characterized and compared two cases of MAC. One is extremely rare in terms of its occurrence in the tongue. The other occurred in the lip, which is common. Histories of disease, diagnosis, and differentials were reviewed by the attending physicians. Hematoxylin and Eosin (HE) slides were evaluated by an experienced pathologist. Immunological markers for malignant eccrine/apocrine gland tumors were used to characterize the tumor’s nature. The examined markers included EMA, CK5/6, CK8/18, CK7, CK20, p63, S-100, Calponin, CD10, MYB, Bcl-2, Her-2, CD34, SMA, p53, CD43, CD117, and Ki-67. Both patients were males, presented with painless lumps in the lower lip and in the tongue, respectively. Both lumps were similar in terms of appearance, being whitish, and infiltrative with irregular borders. Both tumors also had similar histological features with nests of bland keratinocytes, cords, and ductal differentiation filled with Periodic acid–Schiff (PAS)-positive eosinophilic material. In both cases, circular or ovary tumor cells invaded into muscles and nerves. All tumor cells were CK5/6, CK8/18, EMA, and CK7 positive. Particularly, keratinocytes were p63 positive, and paraductal cells were p63, S-100, and SMA positive. Therefore, the rare case of MAC in the tongue appears to derive from the salivary gland.

Sclerosing Microcystic Adenocarcinoma of the Base of Tongue with Signet Ring-Like Cell Component: A Rare Case

“…Sclerosing microcystic adenocarcinoma (SMA) is a unique minor salivary gland neoplasm primarily affecting individuals with a mean age of 56 years and apparent female predominance (F/M: 9/5) ( 4 , 5 ). A few reports of extracutaneous head and neck MAC in the tongue and parotid gland were published in 1995 ( 1 , 6 ). Anne M et al in 2016 reported five patients with MAC-like tumors arising in the mucosal surfaces of the head and neck ( 3 ).…”

Magnetic resonance imaging findings of sclerosing microcystic adenocarcinoma: A case report and review of the literature

“… [13] 55 F Floor of mouth CT Excision and adjuvant radiotherapy Disease free (10) 17 Zhang et al. [14] 51 M Tongue Not stated Excision Disease free (38) 18 Jiang et al. [15] 41 F Tongue Not stated Excision Not stated 19 Tan et al.…”

“…proposed the term “sclerosing microcystic adenocarcinoma (SMA)” for a rare malignant tumor occurring in the salivary glands, closely resembling cutaneous MAC [11] . To our knowledge, 21 cases of SMA have been reported, but none have evaluated the magnetic resonance imaging (MRI) findings of SMA in detail [4] , [5] , [6] , [7] , [8] , [9] , [10] , [11] , [12] , [13] , [14] , [15] , [16] , [17] , [18] . Here, we report an additional case of SMA of the floor of the mouth and discuss its MRI findings.…”

Microcystic adnexal carcinoma of the eyelid and orbit: A case report and review of literature

“…[4] MAC is a benign appearing lesion that often presents as an asymptomatic, slow-growing, indurated, flesh-colored to yellowish nodule, plaque on the central face area, commonly the upper lip, and nasolabial folds. [5] Histologically, MAC is characterized by follicular and sweat gland differentiation and overall benign features; however, it exhibits locally aggressive behavior that typically extends a few centimeters beyond the clinically visible margins, and usually infiltrates deeply into the muscle, cartilage, bone, and nerves. [6] Perineural invasion was commonly seen in MAC and often leads to local recurrence.…”