[A Case of Aggressive Angiomyxoma Completely Resected with Organ Preservation by Preoperative Hormone Therapy].

A 34‒year‒old woman presented with a pelvic tumor in the Douglas pouch during her first pregnancy, initially suspected to be a desmoid tumor and managed subsequently. Biopsy during cesarean section in her second pregnancy confirmed aggressive angiomyxoma (AAM). Postpartum tumor growth prompted a 16‒month course of gonadotropin‒releasing hormone agonist therapy (leuprorelin acetate, 1.88 mg every 4 weeks), which reduced tumor size from 20×13 cm to 10×7.5 cm after 12 doses. However, adverse effects, such as fatigue and nausea occurred, and further tumor shrinkage was minimal, necessitating surgical intervention. A left posterior sacral approach allowed complete tumor resection while preserving the rectum, reproductive organs, and autonomic nerves. AAM is a rare tumor of the pelvis or external genitalia in young women. Although surgical excision remains the primary treatment, no standardized approach exists. This case demonstrates the role of preoperative hormone therapy in significantly reducing tumor size, thereby facilitating complete excision with organ preservation, and underscore its potential role in AAM management.