Study of the frequency of herpesvirus infection reactivation during neoadjuvant chemotherapy in patients with breast cancer

Background. In the structure of oncological diseases, breast cancer ranks among the leading malignancies worldwide. Therefore, studies aimed at developing effective monitoring and prevention strategies for complications potentially associated with infectious agents during polychemotherapy are of significant relevance. Purpose – to investigate and evaluate the frequency of herpesvirus infection reactivation in patients with breast cancer undergoing neoadjuvant chemotherapy. Materials and Methods. The material for the study consisted of saliva and serum samples obtained from patients prior to the initiation of therapy (Period I) and upon completion of the treatment course (Period II). Serological and molecular genetic analyses were performed using flow cytometry with a BioPlex 2200 analyzer and Bio-Rad (USA) test systems, as well as a Rotor-Gene 6000 amplifier (Corbett Research, Australia). Statistical data analysis was carried out using IBM SPSS Statistics for Windows, version 22. Results. The study revealed a high level of statistical significance for the relative risk of reactivation associated with EBV infection – EBV NA IgG, RR = 0.035 (95% CI 0.011–0.109; p < 0.001; χ² = 49.001) and EBV VCA IgG, RR = 0.040 (95% CI 0.015–0.110; p < 0.001; χ² = 51.822). The lowest RR values – 0.033 and 0.050 – indicated the highest risk of systemic EBV DNA reactivation (blood) (95% CI 0.002–0.563; p < 0.001; χ² = 13.241) and active EBV DNA replication (saliva) (95% CI 0.020–0.125; p < 0.001; χ² = 50.443), respectively. The high-risk group also included HSV-1 and HHV-6: HSV-1 IgG, RR = 0.141 (95% CI 0.065–0.307; p < 0.001; χ² = 26.339); HHV-6 IgG, RR = 0.288 (95% CI 0.135–0.614; p < 0.001; χ² = 10.880); and pronounced replicative activity of HSV-1 DNA (saliva), RR = 0.089 (95% CI 0.020–0.405; p < 0.001; χ² = 13.906). In contrast, CMV and HSV-2 demonstrated a lower frequency of reactivation: CMV IgG – 64.1%, RR = 0.360 (95% CI 0.176–0.736; p = 0.005; χ² = 8.008); HSV-2 – 42.2%, RR = 0.196 (95% CI 0.080–0.478; p < 0.001; χ² = 14.196). Markers HSV-2 IgM, CMV IgM, CMV DNA (blood), HSV-3 IgM, and HHV-6 DNA (blood) did not reach statistical significance (p > 0.05). Conclusions. Herpesvirus reactivation may influence the efficacy and outcomes of chemotherapy and contribute to the development of complications in patients with breast cancer.