title: Carcinoid-like pattern in sebaceous neoplasms: another distinctive, previously unrecognized pattern in extraocular sebaceous carcinoma and sebaceoma.
abstract: 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 related to the rippled and labyrinthine/sinusoidal patterns, as exemplified by our cases, in which these arrangements sometimes occurred simultaneously.
authors.affiliation: Sikl's Department of Pathology, Charles University, Medical Faculty Hospital, Pilsen, Czech Republic.
authors.forename: Dmitry V
authors.initials: DV
authors.lastname: Kazakov
authors.forename: Heinz
authors.initials: H
authors.lastname: Kutzner
authors.forename: Arno
authors.initials: A
authors.lastname: Rütten
authors.forename: Petr
authors.initials: P
authors.lastname: Mukensnabl
authors.forename: Michal
authors.initials: M
authors.lastname: Michal
mesh_terms: D018266:Adenocarcinoma, Sebaceous / Q000378:metabolism / Q000473:pathology* / Q000648:ultrastructure; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000032:analysis*; D002276:Carcinoid Tumor / Q000378:metabolism / Q000473:pathology*; D003528:Carcinoma, Adenoid Cystic / Q000473:pathology; D003937:Diagnosis, Differential; D005260:Female; D049669:History, 16th Century; D006801:Humans; D007150:Immunohistochemistry; D002479:Inclusion Bodies / Q000473:pathology; D008297:Male; D046529:Microscopy, Electron, Transmission; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000473:pathology / Q000648:ultrastructure; D018294:Neoplasms, Adnexal and Skin Appendage / Q000473:pathology; D012626:Sebaceous Gland Neoplasms / Q000378:metabolism / Q000473:pathology* / Q000648:ultrastructure
chemical_list: D014408:Biomarkers, Tumor