Carcinoid-like pattern in sebaceous neoplasms: another distinctive, previously unrecognized pattern in extraocular sebaceous carcinoma and sebaceoma

Am J Dermatopathol. 2005 Jun;27(3):195-203. doi: 10.1097/01.dad.0000157464.95204.fc.

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.

Publication types

  • Historical Article

MeSH terms

  • Adenocarcinoma, Sebaceous / metabolism
  • Adenocarcinoma, Sebaceous / pathology*
  • Adenocarcinoma, Sebaceous / ultrastructure
  • Aged
  • Aged, 80 and over
  • Biomarkers, Tumor / analysis*
  • Carcinoid Tumor / metabolism
  • Carcinoid Tumor / pathology*
  • Carcinoma, Adenoid Cystic / pathology
  • Diagnosis, Differential
  • Female
  • History, 16th Century
  • Humans
  • Immunohistochemistry
  • Inclusion Bodies / pathology
  • Male
  • Microscopy, Electron, Transmission
  • Middle Aged
  • Neoplasm Recurrence, Local / pathology
  • Neoplasm Recurrence, Local / ultrastructure
  • Neoplasms, Adnexal and Skin Appendage / pathology
  • Sebaceous Gland Neoplasms / metabolism
  • Sebaceous Gland Neoplasms / pathology*
  • Sebaceous Gland Neoplasms / ultrastructure

Substances

  • Biomarkers, Tumor