Introduction. Criteria for the effectiveness of therapy and the prognosis of disease development remain an urgent problem in oncology. The study of prognostic markers in blood serum is a promising way to track the dynamics of B—cell lymphomas during therapy..

Aim. To analyze the relationship between the presence of a tumor process and the level of the marker E-cadherin.

Materials and Methods. The study included 53 patients (30 men, 23 women) with B-cell lymphomas (stage 1 — 1 patient, stage 2A/2B — 9, 3A/3B — 9, 4A/4B — 34 patients). The level of soluble E-cadherin (sEcad) was determined before the start of treatment, after the third and sixth courses of CT. The dynamics of sEcad levels were performed both in the general group of patients and separately in subgroups of patients without and with recurrent lymphomas. The subgroups were comparable in age and stages of the disease. The control group consisted of 25 people (18 men, 7 women) without oncological pathology. The average age in the study and control groups was 61.2±2.1 (95% CI 57.1–65.3) versus 60.0±2.6 years (95% CI 49.7–60.3), p=0.08. As a normal value (in patients without tumor disease), we assumed a sEcad level of 1.0 ng/ml..

Results. Lymphoma recurrence was observed in 22 (42%) of 53 patients. Seven (13%) patients died of other non-tumor related causes, 1 (2%) patient lost to follow-up. E-cadherin level in the general group before the start of treatment was 3.7 ± 0.4 ng/ml, compared with 0.9 ± 0.1 ng/ml in the control group, p <0.0001. During the therapy, a decrease in the level of E-cadherin was observed after the third and sixth courses of CT to 2.8 ± 0.3 ng/ml and 2.4 ± 0.4 ng/ml, respectively. In the subgroups without relapse (n = 31) and with relapse of lymphomas (n = 22), serum E-cadherin levels before therapy, after three and six courses of chemotherapy were 3.5 ± 0.4, 2.4 ± 0.3 and 1.5 ± 0.2 ng/ml versus 4.1 ± 0.9, 3.4 ± 0.5 and 3.5 ± 0.7 ng/ml, p = 0.5, p = 0.1 and p = 0.003, respectively. Serum E-cadherin level in patients without relapse significantly decreased after 6 courses of CT compared to the time of diagnosis (p = 0.0001). Relapse-free survival (RFS) in the overall patient group was 50.3 ± 8%, with a median follow-up of 43.9 ± 5.2 months. RFS at E-cadherin levels ≤ 1.0 ng/mL and> 1.0 ng/mL after six courses of chemotherapy was 58.3 ± 16% versus 43.3 ± 11% with a mean follow-up of 46.4 ± 10.3 months versus 28.2 ± 4.1 months, respectively (p = 0.045).

Conclusions. The risk of B-lymphoma recurrence is lower at sEcad <1.0 ng/ml after six courses of therapy than at higher values of this marker. A decrease in this marker during treatment indicates a good response to therapy. For further research, it is necessary to expand the observation groups and standardize methods for determining the sEcad level.