title: Hidradenocarcinoma showing prominent mucinous and squamous differentiation and associated pagetoid cells.
abstract: Herein, we report a 63-year-old man presenting with hidradenocarcinoma showing prominent mucinous and squamous differentiation on his back. The tumor was dermal-based, solid and cystic. Tumor cells with squamous differentiation and with keratin pearl formation were identified predominantly in the superficial dermis, and mucinous cells were identified principally in the cystic lesion in the deep dermis. Interestingly, the additional feature of pagetoid cells was identified in the overlying epidermis. Both the mucinous cells in hidradenocarcinoma and pagetoid cells had intracytoplasmic mucin; however, they had different histopathologic findings and immunophenotypes. Mucinous cells in hidradenocarcinoma had small nuclei and abundant intracytoplasmic mucin presenting goblet cells with low rate of positive immunostaining for p53 and Ki67. In contrast, pagetoid cells had larger nuclei with less intracytoplasmic mucin. Both p53- and Ki67-positive cells were increased in pagetoid cells. Additionally, mucinous cells in hidradenocarcinoma were MUC1(+)/MUC2(-)/MUC5AC(+)/MUC6(+), but pagetoid cells were MUC1(+; focal)/MUC2(-)/MUC5AC(-)/MUC6(+; focal). The derivation of pagetoid cells is unclear; however, the localized small region of pagetoid cells over the hidradenocarcinoma in the present case may suggest a common histogenesis of these two malignant neoplasms.
authors.affiliation: Department of Surgical Pathology, Kumamoto University Hospital, Kumamoto, Japan.
authors.forename: Yumi
authors.initials: Y
authors.lastname: Honda
authors.forename: Hiroki
authors.initials: H
authors.lastname: Tanigawa
authors.forename: Miho
authors.initials: M
authors.lastname: Harada
authors.forename: Satoshi
authors.initials: S
authors.lastname: Fukushima
authors.forename: Shinichi
authors.initials: S
authors.lastname: Masuguchi
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Ishihara
authors.forename: Hironobu
authors.initials: H
authors.lastname: Ihn
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Iyama
mesh_terms: D002288:Adenocarcinoma, Mucinous / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D014408:Biomarkers, Tumor / Q000378:metabolism; D002294:Carcinoma, Squamous Cell / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D006801:Humans; D019394:Ki-67 Antigen / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009077:Mucins / Q000378:metabolism; D009378:Neoplasms, Multiple Primary; D010145:Paget Disease, Extramammary / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D013544:Sweat Gland Neoplasms / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism
chemical_list: D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen; D009077:Mucins; D016159:Tumor Suppressor Protein p53