title: Balloon Cell Malignant Melanoma in a Young Female: A Case Report and Review of the Literature.
abstract: Balloon cell malignant melanoma (BCMM) is a very rare malignant melanoma subtype. The clinical appearance of BCMM varies; it may be nodular, ulcerated, polypoid, papillomatous and often non-pigmented. The tumor cells histologically appear large, polygonal or round and contain abundant granular or vacuolated cytoplasm. We herein report the case of a 32-year-old female who presented with a focal eccentric pigmented mass in the left lumbar region of 15 mm in diameter that had been present for several years. She underwent tumor excision. The histopathological analysis showed epithelioid melanocytes with clear cytoplasm. An immunohistochemical analysis revealed that the cells were positive for HMB-45 and S-100 protein and negative for cytokeratin. The balloon cell component stained negative for Fontana-Masson. A month later, the patient underwent excision of the bilateral inguinal lymph nodes and metastatic BCMM was revealed. The lymph node metastases showed the complete replacement of lymph nodes by balloon cells. A diagnosis of BCMM (Breslow depth 10 mm, Clark level V) without ulcer was rendered. Staining with Ki-67 was positive in almost 44% of the balloon cells.
authors.affiliation: Department of Molecular Pathology, Hiroshima University Institute of Biomedical and Health Sciences, Hiroshima, Japan.
authors.forename: Yui
authors.initials: Y
authors.lastname: Hattori
authors.affiliation: Department of Molecular Pathology, Hiroshima University Institute of Biomedical and Health Sciences, Hiroshima, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Sentani
authors.affiliation: Department of Molecular Pathology, Hiroshima University Institute of Biomedical and Health Sciences, Hiroshima, Japan.
authors.forename: Takuya
authors.initials: T
authors.lastname: Hattori
authors.affiliation: Department of Dermatology, Hiroshima University Institute of Biomedical and Health Sciences, Hiroshima, Japan; Department of Dermatology, Hiroshima Kyoritsu Hospital, Hiroshima, Japan.
authors.forename: Yoshimi
authors.initials: Y
authors.lastname: Matsuo
authors.affiliation: Department of Dermatology, Hiroshima University Institute of Biomedical and Health Sciences, Hiroshima, Japan.
authors.forename: Mikio
authors.initials: M
authors.lastname: Kawai
authors.affiliation: Shindo Dermatology and Allergy Clinic, Hiroshima, Japan.
authors.forename: Hajime
authors.initials: H
authors.lastname: Shindo
authors.affiliation: Department of Dermatology, Hiroshima University Institute of Biomedical and Health Sciences, Hiroshima, Japan.
authors.forename: Maiko
authors.initials: M
authors.lastname: Tanaka
authors.affiliation: Department of Dermatology, Hiroshima University Institute of Biomedical and Health Sciences, Hiroshima, Japan.
authors.forename: Michihiro
authors.initials: M
authors.lastname: Hide
authors.affiliation: Department of Molecular Pathology, Hiroshima University Institute of Biomedical and Health Sciences, Hiroshima, Japan.
authors.forename: Wataru
authors.initials: W
authors.lastname: Yasui
keywords: Balloon cell malignant melanoma; Foamy cell; Histopathology; Immunohistochemistry; Lymph node metastasis