Twisting around an axis: A case report of uterine torsion.

INTRODUCTION: A woman presenting with sudden, severe pelvic pain should prompt an evaluation for torsion, most commonly, ovarian torsion. Uterine torsion is rare, especially in a non-gravid uterus. CASE: A post-menopausal woman with known history of uterine leiomyomata presented with sudden, acute pain that was non-amenable to medication. Imaging demonstrated a significant increase in uterine size but was otherwise normal. Primary diagnoses included a degenerative fibroid, leiomyosarcoma, or pelvic thrombosis. Surgical intervention revealed a levo-rotated uterus. Final pathology demonstrated a leiomyosarcoma.
CONCLUSION: Pelvic organ torsion most often presents as sudden pain that is unrelieved by medication. Diagnosis is sometimes made with imaging and Doppler studies. Surgical intervention is often required. In a patient with a rapidly enlarging fibroid uterus with acute pain, one should consider a uterine torsion.

Introduction

Torsion of any pelvic organ most commonly presents with sudden pain that is non-amenable to medication, and is accompanied by nausea, vomiting, and bloating. The pain may be described as intolerable due to the ischemic and compressive nature of the process [1]. Pain may range from mild to severe with shock [2]. While ovarian torsion is the most common, some cases of pedunculated fibroids leading to torsion have also been described. In those instances, imaging may demonstrate evidence of decreased color flow, which can represent ischemia or necrosis, which aids in diagnosis. Uterine torsion presents similarly and is rare, with only 200 cases reported, mostly with a gravid uterus [3]. As of now, there have not been any reported cases of leiomyosarcoma presenting as a uterine torsion.

Patient Information

A 70-year-old, Caucasian, nulligravid woman presented to the emergency department due to complaints of sudden, acute abdominal pain. The patient denied previous similar experiences and had been sitting in her chair when the pain presented. It was initially described as sharp, severe, and radiating to the right shoulder and neck. The pain was associated with nausea and diaphoresis. She had a pertinent medical history of atrial fibrillation, type 2 diabetes mellitus, and hypothyroidism. The patient also had a gynecological history of an enlarging fibroid uterus for which she had undergone dilation and curettage two years prior to presentation. Pathology demonstrated benign, partially degenerated superficial endometrial epithelium. A hysterectomy had been planned. The patient reported a feeling of “bloating” for the past year but no other significant symptoms.

Clinical Findings

The patient appeared uncomfortable and was unable to find relief with medication. Her vital signs demonstrated evidence of hypertension with tachycardia. Her abdomen was soft, non-distended, and tender throughout with mild and deep palpation. There was no guarding or rebound tenderness. A fibroid uterus was palpable with bimanual examination, and the patient had increased pain with palpation. There were no adnexal masses, and there was no cervical or adnexal tenderness.

Diagnostic Assessment

Initial laboratory work-up suggested possible chronic anemia, with a hemoglobin level of 7.7, but was otherwise without significant findings. An abdominal x-ray series did not demonstrate any abnormalities. A CT angiogram was then performed which did not display evidence of vascular occlusion or ischemic changes of the upper abdominal organs. However, there was evidence of moderate ascites, and significant uterine enlargement since previous imaging two years previously, when the uterus measured 16.9 × 11.4 × 12.3 cm. Hypodensities were visualized that were thought to represent necrosis. The working diagnosis was fibroid degeneration, although the possibility of a malignant degeneration into a leiomyosarcoma was also considered. There was no evidence of lymphadenopathy, osteoblastic or osteolytic lesions. A transabdominal and transvaginal ultrasound imaging was performed, with findings significant for an enlarged and lobulated uterus measuring 19.8 × 15.0 × 16.6 cm with multiple uterine fibroids which obscured the underlying endometrium. A small amount of ascites was present in the upper quadrants.

Due to the patient's multiple co-morbidities, the decision was made to proceed with medical stabilization prior to surgical intervention with continued close monitoring. Her hemoglobin level was optimized prior to surgery with two units of packed red blood cells. The patient was then scheduled for an exploratory laparotomy with hysterectomy and bilateral salpingo-oophorectomy. Due to increasing pain, the surgery was moved forward by a day.

Therapeutic Intervention

Upon entry into the abdomen, one liter of blood was evacuated. The uterus was described as bulky, edematous, with multiple masses and visualization was initially limited due to sheer size and bleeding. However, upon packing of the bowel and evacuation of the hemoperitoneum, the uterus was noted to have levo-rotated and torsed upon itself at the level of the junction between the cervix and uterine corpus (Fig. 1). Initial frozen pathology was reported as a ruptured, necrotic fibroid. Hemostasis was eventually obtained, with additional blood given intra-operatively, and the patient was transferred to the post-operative unit in a stable condition.

Fig. 1

Illustration demonstrating 180 degree levorotation of uterus at the utero-cervical junction with fundal, large necrotic fibroid.

Post-operatively, the patient's course was complicated by an ileus but with eventual return of bowel function. The patient was discharged on post-operative day five.

Follow-up and Outcome

A final pathologic diagnosis was delayed to obtain expert consultation. Grossly, the fibroid uterus appeared as a round, soft mass weighing 1540 g and measuring 16.0 × 15.0 × 10.0 cm. A thin rim of pink serosa was surrounding the mass. The serially sectioned specimen revealed soft, tan, fleshy, whorled tissue. Histologic sections of the uterus contained a smooth muscle tumor composed of abundant ordinary spindled smooth muscle elements. An epithelioid tumor component was present both as dispersed present amidst the smooth muscle fascicles as well as in expansile nodular areas of near pure epithelioid growth. Both the ordinary spindled and epithelioid components marked with desmin, caldesmon and smooth muscle actin. The tumor contained foci of necrosis, not of a hyaline type, but of an individual cell nature typical of sarcoma. The spindled component was not cytologically atypical, but the epithelioid component, which occupied more than 50% of the neoplasm, was notably atypical. The mitotic count was 4/10 per high-power field, with some aberrant forms noted. Together, the atypicality, epithelioid differentiation, and necrosis were judged sufficient to establish a diagnosis of leiomyosarcoma with epithelioid features. Given the size and final histological findings, a stage IB sarcoma was diagnosed. The patient was referred to a gynecological oncologist for further management. The patient has since not required any further radiological or chemotherapeutic intervention.

To the authors' knowledge, this is the first case report of a leiomyosarcoma presenting as a uterine torsion. Written consent was obtained for the publication of this case report.

Discussion

Uterine torsion is defined as the rotation of the uterus more than 45 degrees on its long axis, and most commonly occurs at the junction between the cervix and the uterine corpus (1). Dextro-rotation occurs in two-thirds of cases, while levo-rotation is seen in the remaining third [[4], [5], [6]]. The exact mechanism for the occurrence remains unclear, although possible explanation includes weakness of the parametrial tissues following menopause [3,7]. Risk factors for this condition include a large uterine size (such as pregnancy) or a large mass (for example leiomyoma). Piot et al. described a case series in which the most common causes in the gravid uterus were: fibroids in 32%, uterine anomalies (including bicornuate uterus) in 15%, pelvic adhesions in 7%, ovarian cysts or other adnexal mass in 7%, and abnormal fetal presentation or fetal abnormality in 5% and 3%, respectively [8]. The presentation in a non-gravid uterus is extremely rare and diagnosis is most commonly made using imaging, such as ultrasonography or MRI [3,7]. Imaging findings on ultrasound may include: transposition of placental site compared with previous scan, transposition of known uterine leiomyoma compared with previous scan, and Doppler recognition of ovarian vessels anterior to the uterus [9]. In most cases, however, symptoms are non-specific and hence diagnosis is typically not made before surgical intervention [3,4,7,10,11].

Surgical intervention was required for diagnosis of uterine torsion in our case since imaging had failed to demonstrate any overt evidence. Given her post-menopausal state, and rapidly enlarging uterine size, the differential diagnosis included a necrotizing fibroid and pelvic malignancy, but not uterine torsion. This is the first reported case of uterine torsion, to the authors' knowledge, where the causative process was a leiomyosarcoma. The patient's lack of obvious imaging findings, vague symptoms, and multiple co-morbidities may have clouded the pre-operative diagnosis. The significant increase in uterine size prompted a higher suspicion of severe disease. Only during surgery was the diagnosis made but was invaluable in the therapeutic intervention and management of the patient.