Possibility of predicting the efficiency of soft tissue sarcoma treatment on the basis of features of their immunological microenvironment

Aim. To study the possibility of using the evaluation of local cellular immunity factors for predicting the efficiency of soft tissue sarcoma treatment.

Methods. The study included 38 patients with soft tissue sarcoma: 22 with primary and 16 with recurrent tumors, admitted for surgical treatment in 2014-2016. In all patients, the intraoperative tumor tissue samples, peritumoral zone and relatively intact tissue samples corresponding to the resection lines (a total of 114 samples) were studied to assess the local immunity indices. The tissue samples were homogenized, lymphocyte subsets were detected with a flow cytometer.

Results. Characteristics of immunological lymphocytic microenvironment of soft tissue sarcomas were studied in connection with the clinical effect of complex treatment of patients. In primary sarcomas, event-free survival at over 12 months after the surgery was related to higher level of NK-cells in tumor tissue and higher level of NKT-lymphocytes in peritumoral zone and tumor, as well as lower Tregs level than in patients with event-free survival for less than 12 months. In recurrent sarcomas, poor event-free survival was associated with high level of DN-cells in the tumor and peritumoral zone/tumor ratio for CD3+ lymphocytes. All the detected differences were statistically significant (p <0.05).

Conclusion. The clinical effect of complex treatment of soft tissue sarcomas is related to the initial state of immunological microenvironment of the tumor; some indicators of local cellular immunity can be regarded to as prognostic factors different for primary and recurrent sarcomas.