Vulnerability to Infections and Secondary Immunodeficiencies in Patients with Non-Hodgkin's Lymphomas Starting...

Only limited data exist about immune status, secondary immunodeficiencies, and vulnerability to infections in correlation to anti-CD20 antibody-containing therapies (CD20CT) in non-Hodgkin's lymphoma (NHL) patients. Morbidity, mortality, and hospitalisation rates in routine care are not known.

Multicentre prospective observational study of 101 unselected NHL patients who were about to start CD20CT between April, 2021 and December, 2023 in nine haematology/oncology group practices in Germany. With the help of patient diaries, infections and hospitalisations over the course of 1 year were captured and compared to the 3-month period before receiving therapy. Additionally, demographics, treatment data, data on immune status, and death rates were extracted from medical records retrospectively. Data were statistically analysed using IBM SPSS 29 Statistics.

A total of 101 patients with a median age of 68 years (28-90) at the time of enrolment could be analysed. Among them, 58% were male and 42% were female. Of total, 30% suffered from diffuse large B-cell lymphoma, 24% from follicular lymphoma, 20% from chronic lymphocytic leukaemia, and 27% from other NHL. Eight patients died during the observation period. Cause of death was lymphoma in 4 patients, infection/sepsis in 3, and not evaluable in 1. The most frequently used treatment protocols were rituximab/cyclophosphamide/doxorubicin/vincristine/prednisone in 35%, bendamustine/rituximab in 24%, rituximab in 10%, and others in 31%. A quantitative determination of T-helper cells (CD4 lymphocytes) was carried out in only 21 patients (21%). CD4 T-cell count was significantly different before and after initiation of CD20CT (1,048.9/µL vs. 459.7/µL) (p = 0.022). A quantitative determination of the IgG serum trough level was carried out in 22 patients (22%). The difference in mean IgG values before (875.4 mg/dL) and after the start of therapy (738.8 mg/dL) was statistically not significant (p = 0.068). Standardised to 1,000 days, the mean number of infections before treatment was 3.15 compared to 7.00 across all measurement points after the start of therapy (p < 0.001).

Compared to the period before receiving CD20CT, serum IgG levels and T-helper cells decreased and patients suffered from increased infection rates. Immune monitoring is only performed in a minority of patients.