Introduction: Adnexal tumor with Wolffian origin or Wolffian tumor is a very rare neoplasm of the female genital tract that originates from the remnants of the Wolffian duct. Many patients are usually asymptomatic, and the tumor is discovered incidentally during examination or surgery. The broad ligament is the most common site, but it may also occur in the ovary, peritoneum, pelvic wall, and even in males. This study reports one such case of this rare tumor.
Case Presentation: The patient was a 40-year-old asymptomatic woman who had a mass in her right ovary incidentally detected on abdominal ultrasound 4 years ago, but had not followed up. After 4 years, due to refractory urinary frequency since 2 months, she underwent ultrasound and then MRI, and an 8-cm mass in the right ovary with a compressive effect on the bladder was reported. After hysterectomy and bilateral salpingo-oophorectomy, the initial diagnosis was germ cell tumor and ovarian carcinoid, but after repeated microscopic examination, a neoplastic lesion consisting of small cuboidal to polyhedral cells with scant cytoplasm, a cord-like, insular and microfollicular pattern, and eosinophilic secretions within the lumen with 3 mitoses per 10 HPF was observed, and the final and definitive diagnosis of adnexal tumor of wolffian origin was made. The patient was discharged after the surgery and recommended for follow-up of ultrasound.
Conclusion: Wolffian tumor has several important differential diagnoses (granulosa cell tumor, Sertoli-Leydig cell tumor, and clear cell carcinoma), so this tumor should be considered when evaluating female genital neoplasms at any age. Given the tumor's potential for malignancy, recurrence, and metastasis, follow-up of patients is essential.