Background/Aim. The fact that lung carcinomas, like other
solid tumors, can be immunogenic may have a substantial
prognostic value in non-small cell lung cancer (NSCLC). Specific
cytotoxic T-lymphocytes (CTL) can be demonstrated in
most patients with primary tumors of different histological
types. Two main groups of T-lymphocytes participate in the
coupled recognition of tumor-specific antigens – CTL
(CD8+) and helper T-lymphocytes (CD4+). T he a im o f the
study was to assess the relationship between the tumor infiltration
of T-lymphocytes and the therapeutic response to initial
chemotherapy. Methods. Data were obtained from patients
with NSCLC whose therapeutic response after four cycles
of initial platinum-based chemotherapy was observed in
relation to the density of tumor-infiltrating T-lymphocytes
(CD4+ and CD8+) in small tumor biopsy samples. The therapeutic
response was assessed in line with Response Evaluation
Criteria in Solid Tumors (RECIST) 1.1 therapeutic response
evaluation system. Based on the expected therapeutic
response, the patients were divided into three groups: favorable
therapeutic response patients (complete and partial regression),
stable disease patients, and disease progression patients.
To assess the density of CD4+ and CD8+ Tlymphocytes,
the number of lymphocytes was determined at
×200 magnification (1.1 mm2). Three visual fields with the
densest lymphocyte infiltrate were selected for counting, and
the values of all individual fields were added up. Based on the
mean value, the samples were classified into the following
groups: score 0, score 1, score 2, and score 3. During statistical
data processing, low infiltration density combined score 0
and score 1 groups, and high infiltration density combined
score 2 and score 3 groups. Based on the collected data, a database
was created in SPSS 22.0 software and used for further
statistical analysis. Statistical analysis of the data included descriptive
and analytical statistics methods. Results. There
was no significant difference in the distribution of CD4+ Tlymphocytes
and CD8+ T-lymphocytes in the epithelial
component of the tumor between patients with a different
therapeutic response (χ2 = 2.977; p = 0.226 and χ2 = 1.329;
p = 0.515, respectively). There was no significant influence
of the infiltration density of CD4+ T-lymphocytes and
CD8+ T-lymphocytes in the stromal component of the tumor
on the therapeutic response (χ2 = 0.606; p = 0.739 and
χ2 = 5.167; p = 0.076, respectively). Conclusion. The research
did not prove that patients with a high level of tumor-
infiltrating CD4+ and CD8+ T-lymphocytes in the epithelial
and stromal component of the NSCLC had a bette
