Management of High‑Grade Endometrial Stromal Sarcoma (HG‑ESS)

Disease Biology

HG‑ESS is defined by small malignant cells with high‑grade cytology, frequent necrosis, and brisk mitotic activity (>10 mitoses per 10 high‑power fields) — NCCN guidelines 1, 2, 3.
These tumors lack estrogen and progesterone receptor expression, rendering hormonal therapy ineffective — British Journal of Cancer 4.
Reported median overall survival ranges from 16.5 to 53 months, reflecting an intermediate prognosis between low‑grade ESS and undifferentiated uterine sarcoma — NCCN guidelines 1, 2, 3.
Only about 39 % of patients present with disease confined to the uterus/cervix, whereas the majority have extra‑uterine spread — NCCN guidelines 2, 3.

The cornerstone of curative treatment is total abdominal hysterectomy with bilateral salpingo‑oophorectomy (TAH‑BSO); complete en‑bloc resection without residual disease is essential because residual tumor markedly worsens survival — NCCN guidelines 1, 2, 3.

Systemic chemotherapy following the uterine leiomyosarcoma paradigm is recommended for HG‑ESS — British Journal of Cancer 4.
Trabectedin has supporting evidence for use in high‑grade uterine sarcomas — British Journal of Cancer 4.

Adjuvant pelvic radiotherapy has not demonstrated a survival benefit in FIGO stage I–II disease and is therefore not routinely indicated — British Journal of Cancer 4.

Hormonal therapy should be omitted because HG‑ESS does not express hormone receptors — British Journal of Cancer 4.

When feasible, surgical cytoreduction (maximal tumor debulking) should be pursued, as complete resection improves survival outcomes — NCCN guidelines 1, 2.
Neoadjuvant or adjuvant chemotherapy using soft‑tissue sarcoma regimens (e.g., gemcitabine‑docetaxel, doxorubicin‑based protocols) is advised — British Journal of Cancer 4.

Intensive follow‑up is recommended: clinical evaluation every 3–4 months for the first 2–3 years, then every 6 months through year 5, and annually thereafter — British Journal of Cancer 4.
Routine chest imaging is essential to detect pulmonary metastases, which are common in high‑grade uterine sarcomas — British Journal of Cancer 4.

Presence of residual disease after surgery is the most adverse prognostic factor — NCCN guidelines 1, 2, 3.
Advanced stage at presentation (only 39 % confined disease) is associated with poorer outcomes — NCCN guidelines 2, 3.
Additional adverse features include larger tumor size, high mitotic rate, and vascular invasion — NCCN guidelines 2, 3.

The standard initial treatment for endometrial stromal sarcoma is total abdominal hysterectomy with bilateral salpingo-oophorectomy, according to the British Journal of Cancer guidelines 5, 6, 7
For low-grade endometrial stromal sarcoma, total abdominal hysterectomy with bilateral salpingo-oophorectomy is the standard surgical approach, especially due to the hormonal sensitivity of these tumors 5, 6, 7
Lymphadenectomy is not routinely indicated for low-grade endometrial stromal sarcoma as lymph node involvement is less than 5% 6, 7
Patients with low-grade endometrial stromal sarcoma should not receive post-operative hormone replacement therapy containing estrogens 5, 7
For high-grade ESS and undifferentiated endometrial sarcoma, total abdominal hysterectomy is the standard treatment, and bilateral salpingo-oophorectomy may be considered if there is macroscopic involvement 5, 6, 7, 8

Adjuvant pelvic radiotherapy has not been shown to improve survival and is not routinely indicated in FIGO stage I and II disease, as per the British Journal of Cancer guidelines 5, 6, 7
Adjuvant estrogen deprivation therapy is not indicated for early-stage disease, but for advanced/metastatic ESS, estrogen deprivation therapy with an aromatase inhibitor or progestogen is recommended 5, 6, 7
Tamoxifen is contraindicated as its action may be pro-estrogenic in patients with endometrial stromal sarcoma 5, 7

For early-stage uterine adenosarcoma, standard surgical treatment is total hysterectomy and bilateral salpingo-oophorectomy, according to the British Journal of Cancer guidelines 5, 6
For metastatic disease with predominantly epithelial component, endocrine therapy is an option 5, 6
For sarcomatous overgrowth (>25% of tumor volume), systemic treatment along a uterine leiomyosarcoma paradigm is advised 5, 6

The British Journal of Cancer recommends that high-grade sarcoma patients should be followed every 3-4 months in the first 2-3 years, then twice a year up to the fifth year and once a year thereafter, although this specific guideline is from Praxis Medical Insights 9

Hormone replacement therapy containing estrogens is contraindicated in patients with endometrial stromal sarcoma, as stated in the Annals of Oncology and British Journal of Cancer guidelines 5, 7, 8
Treatment decisions should be made in centers with expertise in sarcoma management, according to Praxis Medical Insights, but the British Journal of Cancer also emphasizes the importance of specialized care 10