Adenoid (acantholytic) squamous cell carcinoma of the skin

Abstract

Cutaneous adenoid squamous carcinoma (ASCC) is a distinctive neoplasm featuring tumor cell acantholysis. Because this lesion occasionally may prove troublesome diagnostically, we studied the clinical, histologic, and immunohistochemical features of 55 examples in order to further elucidate its characteristics. ASCC most often occurred in the skin of the head and neck in elderly patients. Of 49 patients in this series, 46 were men and 3 were women; their ages at diagnosis ranged from 25 to 90 yr, with a mean of 71. Six individuals had 2 metachronous neoplasms. ASCC generally behaved in an indolent manner, although 19% of cases did metastasize widely and prove fatal. Tumor size of greater than 1.5 cm appeared to correlate with the risk of an adverse clinical outcome. In addition, 10 patients with ASCC of the skin subsequently developed visceral malignancies. The cutaneous neoplasms were typified by invasive, tubular or pseudoglandular profiles of polygonal cells in the dermis, with glassy eosinophilic cytoplasm and focal squamous pearl formation. Connections to the overlying epidermis were commonly apparent. Immunohistochemically, ASCC demonstrated uniform reactivity for cytokeratin, but lacked markers of specialized glandular cells. These findings militate against the interpretation that such tumors demonstrate partial adnexal differentiation, and show that immunohistology may prove helpful in the differential diagnosis between ASCC and primary or metastatic adenocarcinomas of the skin.

A Case of Acantholytic Squamous Cell Carcinoma

“…However, clinically it can occur on sun-protected areas and histologically there may be no sign of solar damage 5,7,8,15 . In addition, Nappi et al 14 did not find the exact association between A-SCC and acantholytic actinic keratosis in their 55 cases. According to these reasons, it is now thought that acantholytic actinic keratosis is not the precursor lesion of A-SCC.…”

“…Slightly basophilic amorphous material can sometimes be seen within the central spaces, and this material has a suspected glandular origin. But the tumor is negative on both dPAS and mucicarmine staining, and this is unlike other eccrine neoplasms 1,[5][6][7]14 . The overlying epidermis may show hyperkeratosis and parakeratosis, and the connection to the underlying tumor can be seen in most cases 1,2 .…”

“…Although there are no specific risk factors for A-SCC, it is supposed that other predisposing factors for SCC, including immunosuppression, scars, burns and human papillomavirus infection as well as ultraviolet radiation, may be involved in the development of this tumor. It has been documented to arise in areas of pre-existing scarring and in patients with chronic lymphocytic leukemia 8,10,14 . The histopathologic differential diagnosis includes adenoid basal cell carcinoma (BCC), eccrine adenocarcinomas, metastatic adenocarcinomas, and epithelioid angiosarcomas [5][6][7]14 .…”

“…It has been documented to arise in areas of pre-existing scarring and in patients with chronic lymphocytic leukemia 8,10,14 . The histopathologic differential diagnosis includes adenoid basal cell carcinoma (BCC), eccrine adenocarcinomas, metastatic adenocarcinomas, and epithelioid angiosarcomas [5][6][7]14 . BCC must show, at least in part, the typical peripheral palisading, peritumoral lacunae, and stromal mucin.…”

“…Epithelioid angiosarcoma shows positivity for endothelial markers. Metastatic adenocarcinoma shows multiplicity, acantholytic dyskeratosis and the absence of clear epidermal attachments 14,16,17 . The prognosis of A-SCC is matter of debate.…”