Endometrial Stromal Sarcoma

• Endometrial Stromal Sarcoma is a rare uterine cancer originating from the endometrial stromal cells.
• Symptoms often include abnormal vaginal bleeding and pelvic pain, necessitating prompt medical evaluation.
• Diagnosis typically involves imaging, biopsy, and pathological examination of tissue.
• Treatment primarily consists of surgery, often followed by hormone therapy, and sometimes chemotherapy or radiation.
• Prognosis varies significantly based on the tumor’s grade, stage, and individual patient factors.

What is Endometrial Stromal Sarcoma?

Endometrial Stromal Sarcoma (ESS) is a malignant tumor that arises from the connective tissue (stroma) of the endometrium, the tissue lining the inside of the uterus. It is considered a rare form of uterine cancer, accounting for less than 1% of all uterine malignancies. ESS is distinct from the more common endometrial adenocarcinomas, which originate from the glandular cells of the endometrium. It typically affects women in their reproductive years or perimenopause, though it can occur at any age.

ESS is generally classified into two main types: low-grade endometrial stromal sarcoma (LG-ESS) and high-grade endometrial stromal sarcoma (HG-ESS). Low-grade ESS tends to grow slowly and has a more favorable prognosis, often characterized by cells that resemble normal endometrial stromal cells. High-grade ESS is more aggressive, grows rapidly, and has a higher potential for metastasis, with cells that appear more abnormal under a microscope. A less common variant, undifferentiated uterine sarcoma, is even more aggressive and distinct from ESS.

Recognizing Endometrial Stromal Sarcoma Symptoms and Diagnosis

Recognizing the signs of ESS is vital for early detection. The most common endometrial stromal sarcoma symptoms include abnormal vaginal bleeding, which can manifest as postmenopausal bleeding, heavy menstrual bleeding (menorrhagia), or irregular bleeding between periods. Other symptoms may include pelvic pain or pressure, a feeling of fullness in the abdomen, or, less commonly, a palpable pelvic mass. These symptoms are non-specific and can be indicative of many benign gynecological conditions, making accurate diagnosis challenging.

Diagnosis of ESS typically begins with a thorough medical history and physical examination, including a pelvic exam. Further diagnostic steps often involve imaging studies and tissue sampling. Common diagnostic procedures include:

• Transvaginal Ultrasound: To visualize the uterus and assess the endometrial thickness or presence of masses.
• MRI (Magnetic Resonance Imaging): Provides detailed images of the uterus and surrounding pelvic structures, helping to determine the extent of the tumor.
• Endometrial Biopsy or Dilation and Curettage (D&C): Involves taking tissue samples from the uterine lining for pathological examination. This is crucial for definitive diagnosis.
• Hysteroscopy: A procedure where a thin, lighted tube is inserted into the uterus to visualize the endometrial cavity and take targeted biopsies.

The definitive diagnosis relies on the histopathological examination of the biopsied tissue by a pathologist, who can identify the characteristic features of ESS and differentiate between low-grade and high-grade types. According to the American Cancer Society, uterine sarcomas, including ESS, are rare, making accurate pathological diagnosis by experienced specialists essential.

Treatment Approaches and Prognosis for Endometrial Stromal Sarcoma

The primary endometrial stromal sarcoma treatment is surgery. This typically involves a total hysterectomy (removal of the uterus) and bilateral salpingo-oophorectomy (removal of both fallopian tubes and ovaries). Lymph node dissection may also be performed to check for spread. For low-grade ESS, surgery is often curative. In cases where the tumor has spread or for high-grade ESS, additional treatments may be necessary.

Adjuvant therapies, given after surgery, can include hormone therapy, chemotherapy, or radiation therapy. Hormone therapy, often with progestins or aromatase inhibitors, is particularly effective for low-grade ESS, as these tumors are frequently hormone-sensitive. Chemotherapy may be used for high-grade ESS or advanced cases, while radiation therapy might be considered to reduce the risk of local recurrence, especially if the tumor has spread to nearby tissues. The choice of adjuvant therapy depends on the tumor’s grade, stage, and individual patient factors.

The endometrial stromal sarcoma prognosis varies significantly based on several factors, including the tumor’s grade (low-grade vs. high-grade), the stage at diagnosis, and whether the cancer has spread beyond the uterus. Low-grade ESS generally has a favorable prognosis with a high survival rate, especially when detected early and completely removed surgically. High-grade ESS, however, has a poorer prognosis due to its aggressive nature and higher likelihood of recurrence and metastasis. Regular follow-up care is crucial for all patients to monitor for any signs of recurrence. According to the National Cancer Institute, the 5-year relative survival rate for localized uterine sarcoma is approximately 70%, but this varies greatly by specific subtype and stage.