Seroprevalence of SARS-CoV-2 antibodies in patients with hematological and oncological diseases in early 2024.

Introduction: COVID-19 remains a major threat to immunocompromised individuals. The determination of circulating SARS-CoV-2 antibodies in patients at high risk for severe course of SARS-CoV-2 infection is important for estimating the vaccine-induced humoral immune response. Therefore, we assessed the status quo after winter to analyze the need for booster vaccinations.

Methods: Anti-spike IgG levels of 46 hospitalized patients with hematological and oncological diseases, measured between 21th December 2023 and 8th February 2024, were compared between subgroups of patients. Demographic data, underlying diseases, antineoplastic treatment, and the number of positive SARS-CoV-2 tests at the University Hospital Cologne were collected.

Results: Patients with different diseases showed varying SARS-CoV-2 spike antibody levels. The highest levels were found in patients with diffuse large cell B-cell lymphoma (DLBCL) and acute leukemia who had not received specific treatment or had just initiated treatment, whereas the lowest levels were found in patients with DLBCL, acute leukemia, and multiple myeloma who had received at least one line of treatment. The geometric mean antibody titers were higher in female patients than in male patients and were highest in patients aged 41-50 years while lowest in those aged 61-70 years.

Conclusion: The data presented confirm broad variations in SARS-CoV-2 anti-spike IgG levels across patients with different hematological and oncological diseases and highlight the complex interference of cancer biology, immune dysfunction, and treatment-related factors in shaping immune responses. Further research is needed to elucidate the mechanisms underlying these variations in antibody levels. We emphasize the need for regular booster vaccinations in this patient group.