Epidemiological data, etiology, pathogenesis, risk factors, clinical manifestations, modern methods of diagnosis and treatment, prediction of the course of non-Hodgkin lymphoma (literature review)

Non-Hodgkin lymphoma (NHL) is a group of malignant diseases characterized by clonal proliferation of lymphoid cells corresponding to different stages of differentiation of normal B- and T- lymphocytes or natural killer (NK) cells. NHL is histopathologically and clinically diverse and divided into two groups: B-cell lymphomas and T-cell lymphomas, and subtypes: indolent (slow) and aggressive, classic and extranodal. The etiology of NHL is environmental, infectious, immunological, iatrogenic and genetic factors. The pathogenesis of NHL consists in: 1) translocations of oncogenes; 2) cytogenetic aberrations and mutations of tumor suppressor genes. Clinical manifestations of NHL: 1) lymphadenopathy; 2) symptoms of the presence of an extranodal tumor (abdominal pain; jaundice; shortness of breath and/or pleural effusion; bleeding, symptoms of gastrointestinal obstruction; symptoms associated with infiltration by lymphoma cells of the skin, thyroid gland, salivary glands, etc.; neurological symptoms of central and/or peripheral origin); 3) symptoms of bone marrow infiltration; 4) general symptoms (fever, night sweats, weight loss, fatigue, loss of appetite). Diagnosis of NHL involves: 1) auxiliary research (histological, immunohistochemical, cytogenetic and molecular, use of more specific monoclonal antibodies, immunophenotypic diagnosis, gene sequencing); 2) diagnostic tactics (estimation of stage and determination of prognostic factors according to IPI); 3) differential diagnosis (covers other causes of symptoms). The choice of treatment program for NHL depends on the type of lymphoma and the patient's condition. The main methods of treatment: wait and watch; monotherapy with alkylating drugs; RT; combined РCT; combined РCT with the use of purine analogs; therapy with monoclonal antibodies; PCT+monoclonal antibodies; HDCT+THSC. Survival prognosis for NHL depends on the origin of the tumor and its stage.