HMB-45 staining for cytology of primary melanoma of the vagina. A case report.
BACKGROUND
Malignant melanoma in the vagina is very rare, but its diagnosis is usually easy if a melanin pigment is present. With cytodiagnosis, however, it is difficult to differentiate amelanotic melanoma or scantily pigmented melanoma from other conditions. In the present case, monoclonal antibody HMB-45, the efficacy of which has been established in histologic studies, was used in the cytodiagnosis of amelanotic melanoma in the vagina.


METHODS
A woman, aged 78 years, presented with a brownish, nodular tumor, diameter 3 cm, in the vagina. Scraping smears with Papanicolaou staining showed nonepithelial malignant cells without granules suggesting melanin. Smears stained with HMB-45 showed positive immunoreactivity. The diagnosis underwent histologic confirmation of amelanotic melanoma on the initial biopsy.


CONCLUSIONS
Cytodiagnosis was made with HMB-45, which proved very effective in the differential cytodiagnosis of amelanotic melanoma and scantily pigmented melanoma, particularly because it obviated the need for tissue invasion.
Takehara
M
M
Department of Obstetrics and Gynecology, Sapporo Medical University, Chuou-ku South 1 West 16, 060-0061, Sapporo, Japan.
Ito
E
E
Saito
T
T
Nishioka
Y
Y
Ashihara
K
K
Yamashita
S
S
Koizumi
M
M
Kudo
R
R
D000368:Aged; D000951:Antigens, Neoplasm; D005260:Female; D006801:Humans; D008545:Melanoma / Q000378:metabolism* / Q000473:pathology; D058950:Melanoma-Specific Antigens; D009363:Neoplasm Proteins / Q000378:metabolism*; D014625:Vaginal Neoplasms / Q000378:metabolism* / Q000473:pathology
D000951:Antigens, Neoplasm; D058950:Melanoma-Specific Antigens; D009363:Neoplasm Proteins