Cotyledonoid dissecting leiomyoma of the uterus: A report of four cases and a review of the literature

Cotyledonoid dissecting leiomyoma of the uterus: a case report and review of the literature

BACKGROUND

Cotyledonoid dissecting leiomyoma, also named Sternberg tumor, is a rare variant of uterine leiomyoma. The tumor is benign, but the appearance and growth pattern are unusual and alarming. In this article, we report a case of cotyledonoid dissecting leiomyoma in a 55-year-old woman as well as review relevant literature.

CASE PRESENTATION

We report a case of cotyledonoid dissecting leiomyoma in a 55-year-old Iranian woman who presented with vaginal bleeding 4 months after menopause. Ultrasound showed two heterogeneous hypoechoic masses on the uterine fundus. Total abdominal hysterectomy and bilateral salpingo-oophorectomy were performed for the patient. Macroscopically, a large heterogeneous intramural mass (140 mm × 120 mm × 120 mm) with a grape-like exophytic mass on the fundus was observed. Her health status was good after surgery, and the patient was discharged from the hospital after 2 days. In a 1-year follow-up period, no recurrence or any other related complications were found.

CONCLUSION

It is important to recognize this rare variant of leiomyoma to prevent aggressive and inappropriate overdiagnosis and overtreatment. It is suggested to try to use frozen sections for better diagnosis and to preserve fertility in young women suffering from this lesion.

Intraoperative Frozen Section Biopsy of Uterine Smooth Muscle Tumors: A Clinicopathologic Analysis of 112 Cases With Emphasis on Potential Diagnostic Pitfalls

Frozen sections of uterine smooth muscle tumors are infrequently required, and related diagnostic difficulties are seldom discussed. We analyzed the clinicopathologic features of 112 frozen sections of uterine smooth muscle tumors and determined the accuracy, reasons for deferrals, and causes of interpretational errors. Most patients (median age, 45 y) presented with pelvic mass symptoms (53%). The main reasons for a frozen section examination were an abnormal gross appearance including loss of the usual whorled pattern of leiomyoma (36 cases, 32.1%), and intraoperative discovery of an abnormal growth pattern and extrauterine extension of a uterine tumor (28 cases, 25%). There were 9 leiomyosarcomas and 103 leiomyomas, including 18 benign histologic variants. An accurate diagnosis of malignancy was achieved in all leiomyosarcomas, with the exception of a myxoid leiomyosarcoma. In 99 cases (88%), the frozen section diagnosis concurred with the permanent section diagnosis (false positives, 0.9%; false negatives, 0%). Misinterpretation of stromal hyalinization as tumor cell necrosis in a leiomyoma with amianthoid-like fibers was a major discrepancy. Two minor discrepancies did not lead to a change in management. The diagnosis was deferred in 10 cases (8.9%) because of stromal alterations, unusual cellular morphology, uncertain type of necrosis, and abnormal growth patterns. Thus, although various stromal and cellular alterations can cause diagnostic uncertainty, leading to deferrals, frozen section diagnosis of uterine smooth muscle tumors has a high accuracy rate. While a definitive frozen section diagnosis of malignancy may be made when there is unequivocal atypia, indisputable mitotic figures, and tumor cell necrosis, it is important to remember that nonmyogenic mesenchymal tumors may also mimic uterine smooth muscle tumors. In a frozen section setting, it would be sufficient to issue a diagnosis of "malignant mesenchymal tumor." For tumors that do not meet the criteria for malignancy, issuing a frozen section diagnosis of "atypical mesenchymal tumor and defer the histologic subtyping to the permanent sections" is appropriate.

The Management of the Cotyledonoid Leiomyoma of the Uterus: A Narrative Review of the Literature

Cotyledonoid leiomyoma is an unusual uterine myoma due to some ultrasound features that mimic a malignant lesion facilitating the choice of radical surgery. This study aims to summarize the ultrasound and the magnetic resonance imaging aspects of this atypical lesion, and also discuss surgical treatment and pathological exam. It included all English case reports or case series until August 2021 found through PubMed, Google Scholar, and Scopus. A total of 94 cotyledonoid leiomyomas were reported, with a median tumor size of 12 cm. The typical ultrasound image is characterized by a large solid heterogeneous mass, with high vascularity, no shadowing, and indistinct margins within the myometrium. Magnetic resonance imaging shows the presence of merging isointense nodules to the myometrium in T1-weighted images, hyperintense in T2-weighted images, and contrast agent enhancement. Surgical treatment consists of hysterectomy (75 cases, 80%) or myomectomy (19 cases, 20%), without evidence of recurrence if complete. The placenta-like appearance observed during surgery supports this rare fibroid hypothesis. The intraoperative frozen section can be considered. Microscopically, no atypical cells, signs of mitotic activity or cell necrosis are found. To conclude, some preoperative and intraoperative aspects of this lesion are distinctive and may lead surgeons to opt for conservative surgery.

Cotyledonoid Leiomyoma Clinical Characteristics, Imaging Features, and Review of the Literature

Cotyledonoid leiomyoma of the uterus is a rare variant of benign uterine leiomyoma. It has a favorable attitude, despite some ultrasound presentations. A bulky uterus with a heterogeneous mass with irregular margins, high vascularity, and infiltration of the myometrium can induce the suspicion of a malignant mesenchymal tumor and lead to a radical surgical treatment. If present, some imaging features may suggest this rare type of leiomyoma, thus avoiding extensive surgery, especially in young nulliparous women. We report 13 cases of cotyledonoid leiomyoma with clinical characteristics, imaging features, and a literature review.