Virilism and Ectopic Expression of HSD17B5 in Mature Cystic Teratoma

In 2017, a study reported the case of a 31-year-old woman who presented with symptoms of virilism, including hirsutism, hoarseness, and scalp hair loss. Her serum testosterone levels were significantly elevated. Investigations ruled out 21-hydroxylase deficiency as the cause of her virilization. Imaging revealed a mass in her left ovary, which was diagnosed as a mature cystic teratoma (MCT). Pathological analysis showed the tumor contained various tissues, including skin and sweat glands, and was immunoreactive for the enzyme 17beta-hydroxysteroid dehydrogenase (HSD17B5), which converts androstenedione to testosterone. After the tumor was surgically removed, the patient's testosterone levels dropped, and her symptoms improved. This case was the first to report an ovarian MCT causing virilization due to ectopic testosterone production, likely from overexpression of HSD17B5 within the tumor.