Uterine tumor resembling ovarian sex-cord tumor (UTROSCT) is an extremely rare gynecological tumor with low malignant potential. To our knowledge, Clement and Scully  in 1976 were the first to report this uterine stromal neoplasm. Type II UTROSCT is solely composed of sex-cord components and is usually benign or shows low-grade malignancy with occasional local recurrence or distant metastasis . However, recent studies have reported postoperative recurrence and lymphatic metastasis in some cases of UTROSCT [3, 4]. Some authorities proposed that UTROSCT should be categorized as a tumor with undetermined malignant potential. According to the World Health Organization (WHO) 2014 classification, UTROSCT was categorized as an endometrial stromal tumor . Later, the WHO (2020) classification recategorized UTROSCT as a miscellaneous mesenchymal tumor and defined it as a uterine tumor with similar morphology to ovarian sex-cord tumors, lacking recognizable endometrial mesenchymal components . Although there are several reports about UTROSCT in China and abroad [7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19], pathologists still lack sufficient understanding of its clinicopathological features. Here, we report a case of UTROSCT and retrospectively analyze its clinical and pathological characteristics. Additionally, a review of the literature reporting clinical cases of UTROSCT was conducted to understand better this rare gynecological tumor in clinical practice.
A 40-year-old woman underwent a physical examination at our hospital in October 2019, and the gynecological ultrasound examination suggested a right adnexal mass (5.9 cm diameter) and uterine myoma (5.8 cm diameter) with partial liquefaction. She did not have abnormal symptoms, such as hypermenorrhea or a history of abnormal uterine bleeding, and denied a previous medical history of gynecological diseases, family history of malignancy, or history of hereditary syndromes or disorders.
No regular ultrasound reexamination was performed until April 2021, and the results showed an enlarged and morphologically abnormal uterus, a mixed uneven echogenic mass at the posterior wall of the uterus (101 mm × 85 mm, with 7 mm thick endometrium), and a dark cyst (109 mm × 93 mm) in the right adnexal area with dense punctate echo, suggesting suspected uterine myoma with liquefaction and a suspected chocolate cyst. Abdominal computed tomography showed lesions in the pelvis and uterus (
Total hysterectomy and right adnexectomy were discussed based on the pathological conditions and examination results. However, the patient had a fertility requirement, and; therefore, was treated by transabdominal tumor total resection with the removal of the right adnexal mass 1 month later. The tumor was located at the left fundus of the uterus, with no clear boundaries. A little yellow liquid flowed during the resection of the tumor. No. 1 absorbable sutures were used for the interrupted suture of the uterus. The postoperative pathological examination suggested an endometrioid cyst in the right ovary, a uterine stroma–originated tumor with cystic degeneration, and negative margins of the resected specimens (
UTROSCT mostly affects reproductive and postmenopausal women with an average age of 48 years. The youngest case of UTROSCT was reported in a 22-year-old nonpregnant woman . Common clinical manifestations of UTROSCT include abnormal vaginal bleeding and/or enlargement of the uterus. Some patients with UTROSCT may have pelvic pain or discomfort, while others lack typical clinical manifestations and do not seek medical attention until lesions are found in the uterus or pelvis accidentally through imaging examination. UTROSCT usually originates as a single polypoid myomatous nodular mass, and while it mostly grows in the intermural and submucosa of the uterus, reports of cervical UTROSCT are also found in the literature . Our data described the clinical and pathological characteristics of a UTROSCT case.
By performing immunophenotyping of UTROSCT, a broad spectrum of expressed proteins was reported in previous studies, including coexpressed steroid hormone receptors, cytokeratin, smooth muscle markers, and positive markers in ovarian sex-cord–stromal tumors such as inhibin, calretinin, CD56, CD99, melan-A, steroidogenic factor 1 (SF-1), and FOXL2 . The positively expressed calretinin ranks the highest in UTROSCT cases and is considered the most important marker for the differential diagnosis against other uterine lesions with sex-cord–like architectures (such as leiomyoma and leiomyosarcoma) [12, 13]. However, findings of negative expression of calretinin have also been reported in some cases of UTROSCT. Additionally, some studies suggest that the positive staining of SF-1 is an effective marker in distinguishing UTROSCT from other lesions, but the low expression rate of SF-1 might limit its usage. Among the 26 case series collected by Goebel et al. , the positive rate of inhibin was 69.6% (16/23), of which 5 cases had at least 1 positive-stained marker (any 1 or a combination among calretinin, WT-1, and CD56), and those with positive staining of inhibin were all AE1/AE3-positive (8/8) and desmin-positive (12/12). The positive expression rate of hormone receptor SF-1 was 81.8% (9/11) and that of PR was 100% (9/9). In the present case report, immunohistochemical findings excluded endometrial stromal tumor and smooth muscle tumor components. Meanwhile, based on the hematoxylin and eosin staining of tumor sections of the patient and the diagnosis criteria of 2020, the patient was ultimately diagnosed with UTROSCT.
The molecular pathogenesis of UTROSCT remains unclear. Studies have shown that
While total hysterectomy with bilateral adnexectomy is the most common treatment for UTROSCT, the treatment needed should be considered specifically on a case-by-case basis, because age and fertility requirements play an important role in determining whether these surgeries are appropriate. Zhang et al.  had reported 2 cases of UTROSCT, and no recurrence was observed in the 12-year follow-up of the 33-year-old patient after total hysterectomy without reproductive requirement and the 1-year follow-up of the 64-year-old patient after total hysterectomy with bilateral adnexectomy. Jeong et al.  reported a 32-year-old patient with UTROSCT and intramuscular infiltration who conceived after hysteroscopic resection of the tumor. Sato et al.  reported a 57-year-old patient with UTROSCT and sarcoma features who initially underwent transabdominal total hysterectomy with bilateral adnexectomy, and then pelvic and abdominal paraaortic lymphadenectomy and subtotal omentectomy, based on postoperative pathology. The patient did not show recurrence within 36 months after surgery. They concluded that old age, necrosis, lymphatic vascular invasion, significant nuclear atypia, and significant mitotic activity are high-risk factors for malignant UTROSCT, and extensive radical surgery is required to prevent the recurrence and metastasis of UTROSCT. Moore and McCluggage  reviewed the follow-up data and prognosis of UTROSCT with the largest sample size and proposed that UTROSCT with malignant progression usually has necrosis and a mitotic rate ≥1 per 50 high-power fields. Carbone et al.  reported 2 patients with UTROSCT who underwent conservative surgery, with subsequent successful pregnancy outcomes, although the study suggested that radical resection should be considered after childbirth. Watrowski et al.  reported a patient with UTROSCT who received hysteroscopic surgery with a recurrence-free survival of at least 28 months. De Franciscis et al.  reported a patient with UTROSCT who received resectoscopic surgery with successful delivery and a recurrence-free survival of at least 60 months. Minimally invasive surgery might be a feasible option for patients with UTROSCT and fertility requirements; however, this view still needs to be empirically substantiated with more data with long-term follow-up.
UTROSCT is a very rare gynecological tumor. The diagnosis and differential diagnosis of UTROSCT rely mainly on pathological examinations. Therefore, it is necessary to investigate further the histological characteristics, immunophenotypes, and long-term biological behaviors of UTROSCT to improve our understanding of this rare tumor.
A One Health approach to antimicrobial resistance Sialic acid: an attractive biomarker with promising biomedical applications Antibiotic resistance, biofilm forming ability, and clonal profiling of clinical isolates of Staphylococcus aureusfrom southern and northeastern India An 85-amino-acid polypeptide from Myrmeleon borelarvae (antlions) homologous to heat shock factor binding protein 1 with antiproliferative activity against MG-63 osteosarcoma cells in vitro Long noncoding and micro-RNA expression in a model of articular chondrocyte degeneration induced by stromal cell-derived factor-1 Promoter methylation analysis of DKK2may be a potential biomarker for early detection of cervical cancer