Sebaceous carcinoma in situ as a concept and diagnostic entity.

Abstract

Although carcinoma in situ has been accepted as a well-established concept and diagnostic category, for reasons unknown sebaceous carcinoma in situ has not been recognized yet in general pathology or dermatopathology. Such lesions have always been misinterpreted as either benign neoplasm or sebaceous carcinoma. In the present essay, we provide a convincing account supporting sebaceous carcinoma in situ as a valid concept and diagnostic entity via critical literature review and histopathological assessment and illustration. Recognizing sebaceous carcinoma in situ as a valid concept and diagnostic entity will certainly help to avoid misinterpretation and subsequently under or over treatment of such lesions.

HPV-associated Vulvar Intraepithelial Carcinoma With Sebaceous Differentiation: Report of 2 Cases

“…The terminology for purely intraepithelial sebaceous tumors with malignant cytomorphology has varied; other terms reported in literature are intraepithelial or epidermotropic SC. A relatively recent review has recommended the term “sebaceous carcinoma in situ , flat type” for pathology similar to our cases 25 . A discussion can be had about whether the cases reported here represent HPV-driven SC in situ (i.e.…”

Ocular Sebaceous Carcinoma In Situ With Biphenotypic Differentiation: A Reappraisal of the Alternative Origin of the Tumor

“…The entity of sebaceous carcinoma in situ has been proposed in previous studies but wide recognition is still lacking. [12][13][14] Jakobiec, in a series of 150 orbital specimens, reported intraepithelial sebaceous carcinoma without underlying invasive carcinoma in approximately 5% of cases. 2 There were also isolated case reports of ocular sebaceous carcinoma in situ with long-term indolent behavior, even in the presence of small focus of stromal invasion.…”

Spatial analysis of p63, K5 and K7 defines two groups of progenitor cells that differentially contribute to the maintenance of normal sebaceous glands, extraocular sebaceous carcinoma and benign sebaceous tumors

“…32 Several authors noted that there is currently no evidence that extraocular sebaceous carcinoma arises from sebaceous glands. 23,44 In contrast, Komforti et al 24 suggested three histopathological types of precursor lesions for extraocular sebaceous carcinoma, namely flat, nodular and cystic type sebaceous in situ carcinoma, and noted that the latter two designations indicate a sebaceous in situ neoplasia similar to counterparts of other sites. Likewise, the flat type of sebocytic sebaceous carcinoma refers to a proliferation of malignant sebocytes within surface epithelium, also reported in the published work under the term of intraepithelial or epidermotropic sebaceous carcinoma.…”

“…[1][2][3][4][5][6][7] Whereas immunohistochemical techniques for expression of adipophilin, epithelial membrane antigen (EMA), BerEP4 and several other markers are well established in the differential diagnosis of sebaceous gland tumors, [8][9][10][11][12][13][14][15][16][17][18] our information about the exact cellular architecture of these lesions and even of the normal sebaceous gland is still scarce. 23,24 In an effort to build a cellular framework of sebaceous tumors we have, therefore, used triple multicolor stainings [25][26][27] for an analysis of the expression of p63, different keratins, androgen receptor, adipophilin, EMA and Ki-67 in normal sebaceous glands and benign and malignant sebaceous tumors. 23,24 In an effort to build a cellular framework of sebaceous tumors we have, therefore, used triple multicolor stainings [25][26][27] for an analysis of the expression of p63, different keratins, androgen receptor, adipophilin, EMA and Ki-67 in normal sebaceous glands and benign and malignant sebaceous tumors.…”

“…[19][20][21][22] Furthermore, the histogenesis of extraocular sebaceous carcinomas is, in contrast to ocular sebaceous carcinomas, still unclear. 23,24 In an effort to build a cellular framework of sebaceous tumors we have, therefore, used triple multicolor stainings [25][26][27] for an analysis of the expression of p63, different keratins, androgen receptor, adipophilin, EMA and Ki-67 in normal sebaceous glands and benign and malignant sebaceous tumors. Starting with a cohort of 81 benign and malignant sebaceous tumors, including 25 cases of extraocular sebaceous carcinomas and eight cases of normal sebaceous epithelium (published elsewhere), we here focused on 21 tumors (six cases of extraocular sebaceous carcinoma, sebaceoma and adenoma, respectively, and three cases of steatocystomas) and eight cases of normal sebaceous epithelium for multiple immunofluorescence stainings.…”