Atypical (symplastic) uterine leiomyoma masquerading as endometrial malignancy in a 78-year-old post-menopausal Nigerian woman

Abstract Background: The atypical (symplastic) uterine leiomyoma is uncommon and is often characterized by similar macroscopic features as typical uterine fibroid but differs microscopically by having intense cytological features such as enlargement of the nucleus, hyperchromasia, and prominent nucleoli. It lacks histopathological features usually seen in leiomyosarcoma but harbours a low potential of transformation into leiomyosarcoma. Atypical leiomyoma very rarely occurs in post-menopausal women. Case presentation: A 78-year-old postmenopausal woman presented to our gynaecology clinic with an 8-month history of post-menopausal bleeding and abdominal swelling. Physical examination revealed abdominal swelling but blood chemistry was normal. An initial diagnosis of endometrial carcinoma was made and she subsequently had a total abdominal hysterectomy with bilateral salpingo-oophorectomy. Following histopathological evaluations, a confirmatory diagnosis of atypical uterine leiomyoma was made. She has been symptom-free for two years following surgical intervention. Conclusion: Despite their rarity in postmenopausal women, atypical fibroids should be considered in the differential diagnosis for postmenopausal bleeding. Considering the malignant transformation potential, recurrence risk of this pathology, and the completion of family size in this case, hysterectomy is the most preferred treatment option even though myomectomy can be offered to patients with plans of conception in the future.