Topics in histopathology of sweat gland and sebaceous neoplasms

Abstract

This article reviews several topics regarding sweat gland and sebaceous neoplasms. First, the clinicopathological characteristics of poroid neoplasms are summarized. It was recently reported that one-fourth of poroid neoplasms are composite tumors and one-fourth are apocrine type lesions. Recent progress in the immunohistochemical diagnosis of sweat gland neoplasms is also reviewed. CD117 can help to distinguish sweat gland or sebaceous tumors from other non-Merkel cell epithelial tumors of the skin. For immunohistochemical differential diagnosis between sweat gland carcinoma (SGC) other than primary cutanesous apocrine carcinoma and skin metastasis of breast carcinoma (SMBC), a panel of antibodies may be useful, including p63 (SGC + , SMBC ). Comparison of antibodies used for immunohistochemical diagnosis of sebaceous carcinoma (SC) suggests that adipophilin has the highest sensitivity and specificity. Some authors have found that immunostaining for survivin, androgen receptor and ZEB2/ SIP1 has prognostic value for ocular SC, but not extraocular SC. In situ SC is rare, especially extraocular SC, but there have been several recent reports that actinic keratosis and Bowen's disease are the source of invasive SC. Finally, based on recent reports, classification of sebaceous neoplasms into three categories is proposed, which are sebaceoma (a benign neoplasm with well-defined architecture and no atypia), borderline sebaceous neoplasm (low-grade SC; an intermediate tumor with well-defined architecture and nuclear atypia) and SC (a malignant tumor with invasive growth and evident nuclear atypia).

Identification of potentially druggable molecular alterations in skin adnexal malignancies

“…The results showed that almost a third of our cases (31%) were AR positive. Notably, some studies showed that AR detection may be useful for differentiating sebaceous carcinomas, which are usually reported to be AR positive, from basal cell carcinomas or squamous cell carcinomas, which are usually AR negative, [18][19][20][21] and they described absence of AR expression in microcystic adnexal carcinomas 22 and syringoid eccrine carcinomas. 23 Our data on sebaceous and microcystic adnexal carcinomas are in line with these studies, and extend AR expression to other histotypes, such as hidradenocarcinomas (33%), carcinoma NOS (33%), porocarcinomas (17%) and mucinous carcinomas (one case).…”

Synthetic Peptide Drugs for Targeting Skin Cancer: Malignant Melanoma and Melanotic Lesions

“…Other types of skin cancer or adnexal tumors, e.g. sweat gland and sebaceous gland carcinomas [26], non-melanoma nail neoplasms [27], keratoacanthoma [28], Merkel cell carcinoma (APUDoma) [29], are less common and treatment options are varying. Of the non-melanoma skin cancers, BCC is the most abundant (approx.…”

Clinicopathologic Characteristics of Esophageal Ectopic Sebaceous Glands: Chronological Changes and Immunohistochemical Analysis

“…Our results suggest that sebocytes of ectopic sebaceous glands are possibly under hormonal regulation, as hormone receptors (ER, PgR, and AR) are known to be expressed in normal dermal sebaceous glands and in some sebaceous neoplasms. 13 -17 Our cases immunohistochemically exhibited expression of the ER (7/8) and AR (5/8) in esophageal ectopic sebaceous glands, regardless of their sex. All of the 3 AR-negative cases had been biopsied more than 10 years before, and the immunogenicity of the AR might have decreased over time.…”