title: Metastatic hidradenocarcinoma with demonstration of Her-2/neu gene amplification by fluorescence in situ hybridization: potential treatment implications.
abstract: A 44-year-old man was referred for a right chest nodule of 3 months duration. A 'benign' nodule had been excised from this location 8 years prior. On examination, palpable nodes were noted in the right axilla. Radiographic studies were significant only for right axillary lymphadenopathy. Histologically, a nodular dermal proliferation composed of poorly differentiated epithelioid cells in nests and focally forming ducts with pseudopapillary architecture comprised the primary tumor. Features of a clear cell hidradenoma were noted focally. Immunohistochemical (IHC) analysis revealed reactivity for HMW cytokeratins, CK5 and CK7, p53, p63, CEA (focal), androgen receptor, EGFR, estrogen receptor (ER), MUC5AC, and strong/diffuse membranous staining for Her-2/neu. Negative stains included villin, TTF-1, CDX2, S-100 protein, vimentin, gross cystic disease fluid protein 15 (GCDFP-15), mammoglobulin, and MUC2. A wide local excision and axillary node dissection was performed. Metastatic tumor involved nine of 28 nodes. Interphase fluorescence in situ hybridization (FISH) demonstrated chromosomal amplification of the Her-2/neu locus within the tumor and a nodal metastasis. The patient has completed adjuvant and radiotherapy, including trastuzumab, and is asymptomatic. We believe this to be the first demonstration of Her-2/neu amplification in a malignant skin adnexal tumor. In analogy to breast carcinoma, these findings suggest the applicability of trastuzumab for patients with metastatic adnexal carcinomas demonstrating Her-2/neu amplification.
authors.affiliation: Departments of Pathology and Dermatology, University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA.
authors.forename: Jason W
authors.initials: JW
authors.lastname: Nash
authors.forename: Terry L
authors.initials: TL
authors.lastname: Barrett
authors.forename: Merrill
authors.initials: M
authors.lastname: Kies
authors.forename: Merrick I
authors.initials: MI
authors.lastname: Ross
authors.forename: Nour
authors.initials: N
authors.lastname: Sneige
authors.forename: A Hafeez
authors.initials: AH
authors.lastname: Diwan
authors.forename: Alexander J F
authors.initials: AJ
authors.lastname: Lazar
mesh_terms: D006607:Adenoma, Sweat Gland / Q000188:drug therapy / Q000235:genetics* / Q000378:metabolism / Q000601:surgery; D000328:Adult; D000911:Antibodies, Monoclonal / Q000627:therapeutic use; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents / Q000627:therapeutic use; D001365:Axilla; D005784:Gene Amplification; D018734:Genes, erbB-2; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D008197:Lymph Node Excision; D008207:Lymphatic Metastasis / Q000235:genetics* / Q000473:pathology; D008297:Male; D018714:Radiotherapy, Adjuvant; D013544:Sweat Gland Neoplasms / Q000235:genetics / Q000473:pathology*; D035441:Thoracic Wall; D000068878:Trastuzumab
chemical_list: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents; D000068878:Trastuzumab