Vesicovaginal Leiomyoma at 20 Years of Age—A Rare Clinical Entity: Case Report and Literature Review

<b>Background and Clinical Significance:</b> Vesicovaginal leiomyomas are an exceedingly rare form of extrauterine fibroids. They represent less than 1% of all leiomyomas and have been reported in less than 300 cases worldwide since 1733. These benign smooth muscle tumors typically occur in perimenopausal women aged 35-50 years, presenting in young adults extraordinarily uncommonly. The rarity in younger patients creates significant diagnostic challenges, as clinical presentation often mimics malignant entities, particularly embryonal rhabdomyosarcoma. <b>Case Presentation:</b> This paper presents a 20-year-old nulliparous female who developed progressive dyspareunia and urinary dysfunction over 12 months due to a large vesicovaginal mass. Physical examination revealed a 6-7 cm smooth, firm mass obstructing the vaginal canal. Transvaginal ultrasound demonstrated a well-circumscribed, hypoechoic solid lesion measuring 6.9 cm in the vesicovaginal space. Magnetic resonance imaging showed a characteristic T2-hypointense signal with restricted diffusion consistent with leiomyoma, revealing an incidental septate uterus. Ultrasound-guided core needle biopsy confirmed benign leiomyoma with bland spindle cells, absent atypia, and minimal mitotic activity. The patient underwent successful transvaginal enucleation with complete symptom resolution. <b>Conclusion:</b> This case highlights diagnostic challenges posed by benign leiomyomas in young women presenting with solid pelvic masses. Systematic diagnostic approaches incorporating multimodal imaging and guided tissue sampling are essential to avoid misdiagnosis and unnecessary radical surgery. When malignancy is confidently excluded, management should prioritize fertility preservation in young patients.