Case Series and Review of Uterine Lipoleiomyomata
Authors: Ernst Rebecka M , Benge Catherine , Johannesen Eric 
Published: May 2024

Introduction

Uterine lipoleiomyomas are benign neoplasms that are not often seen in clinical practice. First described in 1965, these entities were recognized by a composition of intermixed smooth muscle, mature adipocytes, and fibrous tissue [2,4]. The incidence of lipoleiomyoma has always been accepted as 0.03-0.2% by Willen et al. in 1978 [1,4]. However, recent studies propose a higher incidence at 2.9%, such as Akbulut et al. in 2014. Most commonly found in the uterus, these neoplasms can rarely be associated with the cervix, broad ligament, peritoneum, ovary, as well as other extrapelvic locations. These benign tumors present similarly to uterine leiomyomas in peri- and post-menopausal women with obesity, with symptoms of pelvic/abdominal pain, mild abnormal vaginal bleeding, constipation, increased urinary frequency, and possibly a palpable mass.

Methods

This case series, diagnosed in February and March of 2023, includes the presentation, clinical management, and ultimately pathologic diagnosis of two separate uterine lipoleiomyomas.

Results

A 51-year-old, G3P2, female presented with six months of severe post-menopausal bleeding, severe left-lower quadrant pelvic pain, and lightheadedness. A transvaginal ultrasound revealed a heterogeneous, thickened endometrium of 3.9 centimeters and a probable left ovarian dermoid cyst. CT showed distension of endometrial cavity due to polyps and/or submucosal masses, as well as a fat-containing mass in the uterine corpus. Hysteroscopy with dilation and curettage was performed with pathology of high-grade malignancy. Differential diagnosis at this time included high-grade stromal sarcoma, undifferentiated carcinoma, adenosarcoma, or malignant mixed Mullerian tumor. Patient underwent MRI due to concern for malignancy, which showed FDG-avid endometrial thickening with no other FDG-avid areas of concern. Histopathologic diagnosis found carcinosarcoma of the uterus, two positive lymph nodes, and an incidental finding of lipoleiomyoma. Further medical management will include chemotherapy and vaginal cuff brachytherapy for uterine carcinosarcoma.

A 50-year-old, G5P5, female presented with increasing vaginal spotting and worsening urge incontinence. CT showed increased size of heterogeneous mass in right lateral uterine wall, consistent with previously identified fibroid/leiomyoma. An adjacent fat-containing lesion was identified within the uterine wall. Patient underwent MRI which revealed large uterine mass at fundus with associated fatty component. Due to abnormal rate of growth of fibroid and fat component, there was concern for uterine sarcoma and/or malignant transformation of leiomyoma. Histopathologic diagnosis found lipoleiomyoma with benign atrophic endometrium, paratubal cysts of bilateral fallopian tubes, and follicular cyst of the right ovary. Follow-up in one year was recommended.

Conclusion

Lipoleiomyomas are uncommon benign entities, occurring most commonly in post-menopausal women, similarly to uterine fibroids. While asymptomatic patients can be managed conservatively, these tumors can cause vaginal bleeding, pain, and urinary or fecal incontinence and can be definitively treated with hysterectomy. While imaging is necessary to initially characterize the lesion and determine malignancy concern, histopathologic diagnosis remains the gold standard for diagnosis. Lipoleiomyomas are associated with other gynecologic malignancies, metabolic disorders, and rarely tumor-to-tumor metastasis. For this reason, careful clinical evaluation and surgical management are required for complete evaluation of the patient.