Soft Tissue Sarcomas

Depending on the source of origin in soft tissues, fibrosarcoma, mesenchymoma, liposarcoma, histiocytoma, leiomyosarcoma, rhabdomyosarcoma, synovial sarcoma, angiosarcoma, lymphangiosarcoma, hemangiopericytoma, malignant schwannoma and neurilemmoma are distinguished. The tumor can be located in the soft tissues of the extremities, trunk, retroperitoneum and other areas of the body. Soft tissue sarcomas account for 1% of all malignant tumors.

Early diagnosis is important for prognosis. If a soft tissue tumor is detected, the dynamic observation method should not be used. Errors in diagnosis are common, and the time to establish a diagnosis is often delayed for 6-12 months.

A biopsy or tumor removal is necessary. Soft tissue sarcomas tend to recur after surgery, especially when the size is more than 5 cm and the tumor is poorly differentiated. Distant metastases appear in the lungs, less often in other organs.

Metastases in regional lymph nodes are diagnosed only in 5-20% of patients. Differential diagnosis is carried out with benign tumors, which are much more common than malignant ones, but their malignancy is rarely observed. The diagnosis is based on morphological examination data (fibroma, lipoma, leiomyoma, rhabdomyoma, etc.).

Treatment. The main method of treatment is surgical. Wide removal of tissue adjacent to the tumor is important. To reduce the risk of tumor recurrence after surgery, radiation therapy is used; embryonal rhabdomyosarcomas are more sensitive. Chemotherapy with or without radiation therapy is used for inoperable tumors and metastases.

Chemotherapy regimens: 1) cyclophosphamide - 500 mg/m2 IV in combination with adriamycin - 50 mg/m2 IV on day 1, vincristine - 1 mg/m2 IV on days 1 and 5 and imidazolecarboxamide - 250 mg/m2 IV on days 1–5; 2) carminomycin - 6 mg/m2 IV on days 1, 8 and 15 in combination with vincristine - 1 mg/m2 (or methotrexate - 20 mg/m2) IV on the same days and cyclophosphamide - 250 mg/m2 IV 3 times a week, 6 doses; 3) cyclophosphamide - 500 mg/m2 in combination with adriamycin - 50 mg/m2 on day 1, vincristine - 1 mg/m2 IV on days 1 and 5 and dactinomycin - 0.3 mg/m2 IV on days 3-5; 4) adriamycin - 60 mg/m2 on day 1 in combination with cyclophosphamide - 600 mg/m2 on day 2 and cisplatin - 100 mg/m2 on day 3 intravenously.

In case of single metastases in the lungs, surgical removal can be performed, the feasibility of which is more justified when there is a large interval from removal of the primary tumor to the detection of metastases in the lungs and their slow growth.

The five-year survival rate for soft tissue sarcomas ranges from 20 to 80% depending on the morphological structure and differentiation of the tumor, its size and location.