The postoperative decrease in IgA and IgM levels may impair the body’s specific antibody production, undermining resistance to infectious diseases and potentially impacting long-term oncological outcomes, while simultaneously compromising the production of tumor-specific antibodies essential for opsonization and enhancement of phagocytosis by macrophages and dendritic cells, critical for the effective functioning of the complement system and support of CTLs’ anti-tumor activity (28). The gene discussed is CD79A; the disease is neoplasm.