What are the recommended evaluation and treatment options for a reproductive‑age woman with an ovarian leiomyoma?

Ovarian Leiomyoma: Evaluation and Management in Reproductive-Age Women

Initial Evaluation

For a reproductive-age woman with an ovarian leiomyoma, surgical excision with histologic confirmation is the only reliable diagnostic and therapeutic approach, as preoperative imaging cannot definitively distinguish this rare benign tumor from malignancy. 1

Diagnostic Challenges

• Ovarian leiomyomas account for only 0.5–1% of all benign ovarian tumors and are almost never diagnosed preoperatively. 2
• These tumors typically present as solid adnexal masses (47% of cases) or are discovered incidentally during evaluation for uterine leiomyomas (26% of cases). 3
• Transvaginal ultrasound with Doppler and CT imaging cannot reliably differentiate ovarian leiomyomas from primary ovarian malignancies, particularly when the mass is large or cystic. 1, 4
• The mean age at presentation is 45.8 years, with most cases occurring during reproductive years. 3

Key Clinical Features

• Association with uterine fibroids: 78% of ovarian leiomyomas occur in women who also have uterine leiomyomas, making concurrent evaluation of the uterus essential. 3
• Size spectrum: Most ovarian leiomyomas are small and asymptomatic, but they can become symptomatic as size increases. 2
• Rare presentations: Giant ovarian leiomyomas may present with ascites, polymyositis, or mimic ovarian malignancy on imaging. 1, 4

Surgical Management Algorithm

For Reproductive-Age Women Desiring Fertility

Ovary-preserving surgery (cystectomy or wedge resection) should be performed when technically feasible, as these tumors are benign and fertility preservation is paramount. 2

• Surgical approach should involve careful intraoperative assessment to confirm the mass is entirely ovarian in origin without capsular breach. 5
• Frozen section cannot reliably distinguish leiomyoma from leiomyosarcoma due to difficulty identifying mitoses; permanent sections are required for definitive diagnosis. 6
• If the ovarian mass appears suspicious intraoperatively or the ovary cannot be preserved, unilateral salpingo-oophorectomy is appropriate. 5

For Women Who Have Completed Childbearing

• Total abdominal hysterectomy with bilateral salpingo-oophorectomy is the definitive treatment when fertility preservation is not desired, particularly when concurrent uterine leiomyomas are present. 5
• This approach eliminates recurrence risk and allows estrogen-only hormone replacement therapy at menopause. 7

Histologic Confirmation Requirements

• Macroscopic examination: The mass should be entirely within the ovary, appearing as a grey-white solid tumor without capsular breach. 5
• Microscopic features: Ovarian leiomyomas exhibit a spectrum similar to uterine leiomyomas, with most having mitotic indices <1/10 high-power fields. 3
• Immunohistochemistry: Desmin positivity and Masson trichrome staining confirm smooth muscle origin and aid diagnosis in difficult cases. 5
• Cellular variants: Cellular leiomyomas and those with mitotic indices between 1–2/10 HPFs average 3.4 cm in size but remain benign. 3

Critical Management Pitfalls

• Do not rely on preoperative imaging alone: Even advanced imaging modalities cannot definitively exclude malignancy; surgical excision with histologic evaluation is mandatory. 1
• Avoid overtreatment in young women: Radical surgery with bilateral oophorectomy should be avoided when ovary-preserving surgery is technically feasible in reproductive-age women. 2
• Screen for concurrent pathology: Evaluate for uterine leiomyomas (present in 78% of cases) and hyperplastic endometrial polyps (present in 13% of cases). 3
• Counsel about benign prognosis: Despite the rarity and diagnostic uncertainty, ovarian leiomyomas have excellent prognosis with no recurrence in available follow-up studies (mean 9.6 months). 3

Postoperative Considerations

• Follow-up should include surveillance for recurrence, though the natural history suggests benign behavior with no documented recurrences. 3
• If concurrent uterine leiomyomas are present and symptomatic, manage according to standard uterine fibroid treatment algorithms based on fertility desires and symptom severity. 8, 7
• Women who undergo ovary-preserving surgery should be counseled that the ovarian tumor itself has excellent prognosis, but concurrent uterine fibroids carry a 27% recurrence rate at 10 years if treated with myomectomy. 8, 7