This report emphasizes a carcinoid- like pattern, a previously unrecognized feature in cutaneous sebaceous neoplasms. We report 7 patients with sebaceous tumors in which neoplastic cells were arranged in a trabecular ...This report emphasizes a carcinoid- like pattern, a previously unrecognized feature in cutaneous sebaceous neoplasms. We report 7 patients with sebaceous tumors in which neoplastic cells were arranged in a trabecular and ribbon- like pattern or formed rosettes/pseudorosettes. The cases included 6 men and 1 woman, with their ages at the diagnosis ranging from 43 to 87 years (median age, 59). All patients presented with a solitary lesion. Locations were the scalp (n=6) and forearm (n=1). The carcinoid- like arrangement of neoplastic cells was the sole pattern in 4 cases, and in 3 cases the so- called labyrinthine/sinusoidal and/or rippled patterns were seen in addition. Sebaceous differentiation in the form of mature sebocytes varied from almost none to approximately 10% . Although the neoplasm appeared benign architecturally, the presence of cytologic atypia qualified 2 tumors as low- grade carcinomas. Four lesions represented sebaceomas, and in 1 case microscopic delineation between a carcinoma and sebaceoma was difficult. No neuroendocrine differentiation was demonstrated immunohistochemically, histochemically, and ultrastructurally. Electron microscopic examination performed in 1 case of carcinoma revealed lipid vacuoles in a minority of cells. There were no membrane- bound neuroendocrine granules. Rare cells contained peculiar large helioid inclusions. We conclude that the carcinoid- like pattern is another distinctive pattern indicative of sebaceous neoplasms. This pattern seems to be closely relatedtotherippledandlabyrinthine/sinusoidalpatterns,asexemplified by our cases, in which these arrangements sometimes occurred simultaneously.展开更多
文摘This report emphasizes a carcinoid- like pattern, a previously unrecognized feature in cutaneous sebaceous neoplasms. We report 7 patients with sebaceous tumors in which neoplastic cells were arranged in a trabecular and ribbon- like pattern or formed rosettes/pseudorosettes. The cases included 6 men and 1 woman, with their ages at the diagnosis ranging from 43 to 87 years (median age, 59). All patients presented with a solitary lesion. Locations were the scalp (n=6) and forearm (n=1). The carcinoid- like arrangement of neoplastic cells was the sole pattern in 4 cases, and in 3 cases the so- called labyrinthine/sinusoidal and/or rippled patterns were seen in addition. Sebaceous differentiation in the form of mature sebocytes varied from almost none to approximately 10% . Although the neoplasm appeared benign architecturally, the presence of cytologic atypia qualified 2 tumors as low- grade carcinomas. Four lesions represented sebaceomas, and in 1 case microscopic delineation between a carcinoma and sebaceoma was difficult. No neuroendocrine differentiation was demonstrated immunohistochemically, histochemically, and ultrastructurally. Electron microscopic examination performed in 1 case of carcinoma revealed lipid vacuoles in a minority of cells. There were no membrane- bound neuroendocrine granules. Rare cells contained peculiar large helioid inclusions. We conclude that the carcinoid- like pattern is another distinctive pattern indicative of sebaceous neoplasms. This pattern seems to be closely relatedtotherippledandlabyrinthine/sinusoidalpatterns,asexemplified by our cases, in which these arrangements sometimes occurred simultaneously.
