Tohoku J. Exp. Med., 2017 February, 241(2)

Virilism and Ectopic Expression of HSD17B5 in Mature Cystic Teratoma

YOHEI KAWAGUCHI,¹ HIROKO MIZUNO,¹ MAI HORIKAWA,² MAYUKO KANO,¹ KENGO YAMADA,¹ FUMIKO YAMAKAWA,¹ TAKASHI MAEKAWA,³ YUTO YAMAZAKI,³ KEELY M. MCNAMARA,³ HIRONOBU SASANO³ and MASAYUKI HAYASHI¹

¹Department of Endocrinology and Diabetes, Japan Community Health care Organization Chukyo Hospital, Nagoya, Aichi, Japan
²Department of Obstetrics and Gynecology, Japan Community Health care Organization Chukyo Hospital, Nagoya, Aichi, Japan
³Department of Pathology, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan

Mature cystic teratoma (MCT) is rarely involved in the overproduction of steroid hormones in contrast to sex cord stromal tumors. A 31-year-old woman visited our hospital with hirsutism, hoarseness, and hair loss from the scalp. Serum testosterone and free-testosterone levels were 7.3 ng/ml and 2.3 pg/ml, respectively, which were markedly in excess of the age adjusted female standard levels. Basal blood levels of steroid hormones and serum levels of 17-hydroxyprogesterone at 1 h after intravenous injection of adrenocorticotropic hormone demonstrated that 21-hydroxylase deficiency was not the underlying cause of her virilization. A subsequent chromosomal test with G-banding revealed a karyotype of 46XX. Magnetic resonance imaging revealed a mass in the left ovary, which was subsequently diagnosed as MCT. Detailed pathological analysis of the tumor indicated that it was comprised of skin components, sweat glands, with hair and fat texture, glandular epithelium and fibrous connective tissue, consistent with the characteristic composition of MCT. Immunohistochemical analysis demonstrated marked immunoreactivity of 17beta-hydroxysteroid dehydrogenase (HSD17B5), an enzyme that can convert androstenedione to testosterone. Following surgical removal of the tumor, testosterone and free testosterone levels were markedly decreased (0.3 ng/ml and 0.4 pg/ml, respectively) and other symptoms abated. In conclusion, this is the first report of an ovarian MCT associated with clinical virilization caused by the ectopic production of testosterone possibly because of an overexpression of intratumoral HSD17B5.

keywords —— 17beta-hydroxysteroid dehydrogenase; immunohistochemistry; mature cystic teratoma; testosterone; virilism

© 2017 Tohoku University Medical Press

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Tohoku J. Exp. Med., 2017, 241, 125-129

Correspondence: Masayuki Hayashi, Department of Endocrinology and Diabetes, Japan Community Health Care Organization Chukyo Hospital, 1-1-10 Sanjo, Minami-ku, Nagoya, Aichi 457-8510, Japan.

e-mail: hayashi-masayuki@chukyo.jcho.go.jp