What Is an Endometrial Stromal Sarcoma?

Endometrial stromal sarcoma is a tumor derived from endometrial stromal cells. According to the histological and clinical characteristics of tumors, they are divided into two categories, namely low-grade endometrial stromal sarcoma and high-grade endometrial stromal sarcoma. Low-grade malignant endometrial stromal sarcoma, which was previously called intravascular lymphostroma, intralymphatic interstitial myopathy, etc., accounts for about 80%. The disease progresses slowly and the prognosis is good. Highly malignant endometrial stromal sarcoma has a high degree of malignancy, rapid disease progression, easy invasion and metastasis, and poor prognosis. The pathological characteristics of the two are also different.

Basic Information

English name: endometrial stromal sarcoma
Visiting department: Obstetrics and Gynecology

Common symptoms: Irregular vaginal bleeding, increased menstruation, vaginal drainage, anemia, lower abdominal pain, etc.

Causes of endometrial stromal sarcoma

The interstitial cells originated from the endometrium of the cervix, and the etiology and mechanism are not yet clear.

Clinical manifestations of endometrial stromal sarcoma

1. Irregular vaginal bleeding, increased menstruation, vaginal drainage, anemia, lower abdominal pain, etc.

2. The uterus is enlarged. Early pelvic examination is similar to uterine wall fibroids.

3. A soft, brittle, bleeding polyp-like mass was found from the cervix or vagina.

4. Mass ulceration and infection, can have extremely vaginal discharge.

Endometrial stromal sarcoma examination

1. Microscopy characteristics

Endometrial glands are scattered, reduced, or even completely disappeared.

Tumor cells are uniformly dense, spindle-shaped, round, or polygonal, with large nuclei, giant tumor cells are rare, nuclear divisions are numerous, and the cytoplasm is somewhat variable. In rare cases, they are similar to decidual cells and adenoid differentiation may occur.

Different types of sarcoma cells: small atypia, invasive growth of tumor cells and mitotic figures are the main basis for diagnosis of sarcomas. When the tumor cells are highly heterogeneous, malformed nuclei, giant nuclei, and multinuclei can appear. When doing silver staining, each tumor cell is in the silver-fighting fibers.

Tumor cell cytoplasm looks like endometrial stromal cells in the early proliferative phase.

2. Preoperative diagnosis and curettage

It has certain value for endometrial stromal sarcoma, but its polypoid lesions have wide bases and have certain limitations in diagnosis and curettage.

3. Color Doppler determination

Detection of blood flow signals and blood flow resistance in uterus and mass. Those with low obstruction blood flow must highly suspect uterine sarcoma.

4.B-ultrasound

The uterus is significantly enlarged, the tumor boundary is irregular, and the muscle layer is unclear. The echo is a uniform low echo, or a cellular honeycomb-like uneven strength echo, similar to hydatidiform mole.

Diagnosis of endometrial stromal sarcoma

1. When diagnosing cervical polyps, endometrial polyps, and submucosal fibroids, a pelvic examination reveals polypoid-like protrusions at the cervix, and you should be alert to the possibility of endometrial stromal sarcoma.

2. The tumor forms a polypoid or nodule from the endometrium to the uterine cavity or beyond the mouth of the cervix. The tumor volume is larger than that of general polyps, the pedicle is wide, and the texture is soft and brittle.

3. Nodules or diffuse distribution of tumors in the muscular layer, but the boundaries are unclear, and it is not easy to remove them completely.

4. The tumor section was fish-like, with bleeding, necrosis, and cystic changes.

Differential diagnosis of endometrial stromal sarcoma

Endometrial polyps

Frequent, pediceled, thinner and smaller.

2. Uterine submucosal fibroids

Prolapse from the uterine cavity to the vagina, fast growth, rich blood flow signals, low impedance spectrum, CA125 in some patients can increase serum.

3. Differential intrauterine adenocarcinoma

Cancer cells are spindle-shaped, reticulated, nest-shaped or lamellar.

Reticulum fiber staining showed reticulum fibers surrounding the cancerous nest.

Immunohistochemistry: Keratin (+), EMA (+), CEA (+), Vimentin (-).

4. Leiomyosarcoma

Tumor cell morphology and size can be diverse, disorderly arranged, invasive growth.

Obvious nuclear atypia with more than 10/10 HPF

Immunohistochemistry: Vimentin (+), SMA (+), Desllin (+), Keratin (-).

Masson's trichrome tumor cells are red, and MaIlory's hematoxylin phosphotungate staining shows longitudinal muscle filaments in the cytoplasm.

Endometrial stromal sarcoma treatment

Surgical treatment

For patients who have been diagnosed with uterine sarcoma, prompt surgical treatment should be considered.

(1) The scope of surgery for low-grade endometrial stromal sarcoma : a total hysterectomy and double appendectomy, it is not advisable to retain the ovaries. Even if extensive metastases occur, the lesion should still be as clear as possible. Lung metastases were performed in patients with lung metastases.

(2) Highly malignant endometrial stromal sarcoma is prone to recurrence after surgery. For advanced patients, palliative surgery can be performed to relieve symptoms, postoperative adjuvant radiotherapy and chemotherapy.

2. chemotherapy

(1) Low-grade malignant endometrial stromal sarcoma is administered with cisplatin (DDP) or ifosfamide once every 3 weeks.

(2) IAP protocol (Ifosfamide + ADM + cisplatin) for highly malignant endometrial stromal sarcoma .

3. Radiotherapy

Indications: Patients with residual lesions after surgery, patients with stage I or higher, highly malignant endometrial stromal sarcoma.

(1) The external irradiation after surgery needs to make a treatment plan according to the postoperative residual tumor and metastases. The setting of the external irradiation after surgery is roughly the same as the postoperative preventive pelvic irradiation.

For example, there is a residual sarcoma in the central part of the pelvis: the tumor volume of the whole pelvic irradiation is increased to 40Gy, and the central lead block four-field irradiation is still 15Gy.

Large pelvic wall mass: After completing the whole pelvic and four-field irradiation, you can shrink the field to irradiate 10-15Gy.

Positive abdominal aortic lymph nodes: Another field was set up. The irradiation dose was 45 to 55 Gy, 8.5 Gy per week, and completed in 4 to 6 weeks.

When the lesion area exceeds the pelvic area, an additional field can be added to the upper abdomen. The area of the irradiation field is determined according to the lesion area. Lead and liver parts need to be covered by lead. If the scope of lung metastases is small, the field of lung metastases can be irradiated in vitro.

(2) Remote cavity post- cavity radiotherapy is used before intracavitary radiosurgery .

Dose: Based on the reference point (point A) of cervical cancer intracavitary radiotherapy, 15-20Gy is appropriate. It is best to make the uterus a uniformly distributed dose.

When there is a residual sarcoma in the vaginal stump after surgery, after the whole pelvic irradiation in vitro, intraluminal radiation can be supplemented at the same time as the pelvic four-field irradiation. The dose reference point is 0.3cm below the mucosa, and a total of 24-30Gy can be given in 3 to 5 times Completed with an interval of 4-7 days,

4. Progestogen therapy

Indications: Progesterone receptor, estrogen receptor positive patients.

Note: It should be applied for a long time, and generally recommended for more than 1 year.

Common drugs:

(1) Megestrol acetate is taken orally and maintained for a long time.

(2) Medroxyprogesterone is taken orally and maintained for a long time.

(3) Intramuscular injection of hydroxyprogesterone hexanoate, or long-term maintenance of the above-mentioned oral medicine.

For those who are negative for progesterone receptors, first use tamoxifen to increase the sensitivity of the tumor to progestin drugs, and then apply medroxyprogesterone (MPA) or MA.