Uterine sarcomas are a group of disparate, aggressive cancers of the uterine corpus. Common manifestations include abnormal uterine bleeding and pelvic pain or mass. For suspected uterine sarcoma, endometrial biopsy or dilation and curettage may be done, but results are often falsely negative; most sarcomas are diagnosed histologically after hysterectomy or myomectomy. Treatment requires total abdominal hysterectomy and bilateral salpingo-oophorectomy; for advanced cancer, chemotherapy and sometimes radiation therapy are indicated.
Uterine sarcomas are rare, accounting for 2 to 5% of all uterine cancers (1). Leiomyosarcoma and endometrial stromal sarcoma are the most common types. Average age at diagnosis is 60 years old. Uterine leiomyosarcoma incidence in the United States is 2 times higher in Black women than in White women.
Risk factors for uterine sarcomas are
Prior pelvic radiation
Uterine sarcomas include
Leiomyosarcoma (the most common subtype [63%])
Endometrial stromal sarcoma (21%)
Undifferentiated uterine sarcoma
Rare uterine mesenchymal sarcoma subtypes include
Adenosarcomas
Perivascular epithelioid cell tumor (PEComas)
Rhabdomyosarcoma
Carcinosarcomas used to be categorized as sarcomas but are now considered and treated as high-grade epithelial tumors (carcinomas).
High-grade uterine sarcomas tend metastasize hematogenously, most often to the lungs; lymph node metastases are uncommon.
General reference
1. American Cancer Society: Key Statistics for Uterine Sarcoma. Accessed July 14, 2023.
Symptoms and Signs of Uterine Sarcomas
Most sarcomas manifest as abnormal uterine bleeding and, less commonly, as pelvic pain, a feeling of fullness in the abdomen, a mass in the vagina, frequent urination, or a palpable pelvic mass.
Diagnosis of Uterine Sarcomas
Histology, most often after surgical removal
Symptoms suggesting uterine sarcoma usually prompt transvaginal ultrasonography and endometrial biopsy or dilation and curettage (D & C). However, these tests have limited sensitivity for sarcoma. Endometrial stromal sarcoma and uterine leiomyosarcoma are often incidentally diagnosed histologically after hysterectomy or myomectomy.
If cancer is identified preoperatively, CT or MRI is typically done. If uterine sarcoma is diagnosed after surgical removal, imaging is recommended, and surgical re-exploration can be considered to complete staging.
Screening for Lynch syndrome (hereditary nonpolyposis colorectal cancer) is not usually done when patients have uterine sarcoma because this genetic syndrome increases risk of endometrial carcinoma, not sarcoma.
Staging
Staging is done surgically (see tables FIGO Surgical Staging of Uterine Sarcoma: Leiomyosarcoma and Endometrial Stromal Sarcoma and FIGO Surgical Staging of Uterine Sarcoma: Adenosarcoma).
Treatment of Uterine Sarcomas
Total abdominal hysterectomy and bilateral salpingo-oophorectomy
Usually adjuvant pelvic radiation therapy
Chemotherapy for advanced or recurrent cancers
(See also National Comprehensive Cancer Network (NCCN): NCCN Clinical Practice Guidelines in Oncology: Uterine Sarcomas.)
Treatment of uterine sarcomas is total abdominal hysterectomy and bilateral salpingo-oophorectomy.
Uterine sarcomas should be removed en bloc; morcellation is contraindicated. If a specimen is fragmented during surgery, imaging is recommended to check for metastases, and re-exploration can be considered. Treatment with chemotherapy is also recommended.
The ovaries may be preserved in certain patients with early-stage uterine leiomyosarcoma if they wish to retain hormonal function. Additional surgical resection should be based on intraoperative findings.
Lymphadenectomy in patients with leiomyosarcoma or endometrial stromal sarcoma is not indicated because there is evidence that the risk of lymph node metastases is minimal (< 2%) (1, 2).
For inoperable sarcomas, pelvic radiation therapy with or without brachytherapy and/or systemic therapy is recommended.
Adjuvant radiation therapy is typically used and appears to delay local recurrence but does not improve overall survival rate.
Chemotherapy agents are typically used when tumors are advanced or recur; drugs vary by tumor type.
Some preferred regimens are
Overall, response to chemotherapy is poor.
3).
Endocrine therapy is used for patients with endometrial stromal sarcoma or hormone receptor–positive uterine leiomyosarcoma. Progestins are frequently effective. Endocrine therapy may include:
Aromatase inhibitors
GnRH (gonadotropin-releasing hormone) agonists
Treatment references
1. Smith ES, Jansen C, Miller KM, et al: Primary characteristics and outcomes of newly diagnosed low-grade endometrial stromal sarcoma. Int J Gynecol Cancer 32(7):882-890, 2022. Published 2022 Jul 4. doi:10.1136/ijgc-2022-003383
2. Leitao MM, Sonoda Y, Brennan MF, et al: Incidence of lymph node and ovarian metastases in leiomyosarcoma of the uterus. Gynecol Oncol 91(1):209-212, 2003. doi:10.1016/s0090-8258(03)00478-5
3. Pautier P, Italiano A, Piperno-Neumann S, et al: Doxorubicin alone versus doxorubicin with trabectedin followed by trabectedin alone as first-line therapy for metastatic or unresectable leiomyosarcoma (LMS-04): a randomised, multicentre, open-label phase 3 trial. Lancet Oncol 23(8):1044-1054, 2022. doi:10.1016/S1470-2045(22)00380-1
Prognosis for Uterine Sarcomas
Prognosis for patients with uterine sarcomas is generally poorer than that with endometrial carcinoma of similar stage; survival is generally poor when the cancer has spread beyond the uterus.
In one study, 5-year survival rates were (1)
Stage I: 51%
Stage II: 13%
Stage III: 10%
Stage IV: 3%
Most commonly, the cancer recurs locally, in the abdomen, or the lungs.
Prognosis reference
1. American Cancer Society: Survival Rates for Uterine Sarcoma. Accessed August 31, 2023.
Key Points
Uterine sarcomas are uncommon.
Symptoms include abnormal vaginal bleeding, a mass in the vagina, pelvic pain, a feeling of fullness in the abdomen, and frequent urination.
Prognosis is generally worse than that with endometrial carcinoma of similar stage.
Treat most patients with total abdominal hysterectomy, bilateral salpingo-oophorectomy, and adjuvant radiation.
Treat patients who have endometrial stroma sarcoma and hormone receptor–positive leiomyosarcomas with endocrine therapy.
Treat inoperable sarcomas with radiation therapy and/or chemotherapy.
More Information
The following English-language resource may be useful. Please note that THE MANUAL is not responsible for the content of this resource.
National Cancer Institute: Uterine Cancer: This web site provides links to information about genetics and treatment of uterine sarcomas (a type of uterine cancer), as well as links to statistics and supportive and palliative care.
