[Immunosuppression in Cancer: Strategies for Infection Prevention].

Antimicrobial prophylaxis is an important cornerstone for reducing morbidity and mortality of cancer patients. Important strides have been made in recent years in vaccination, drug prophylaxes and the use of growth-factor support. We detail these changes to the respective recommendations here.Patients with malignant disease are recommended to receive vaccinations against common respiratory pathogens (COVID-19, influenza, pneumococci, and RSV). For both influenza (now trivalent vaccine) and pneumococci (now PCV20), the preferred vaccine has changed. A VZV vaccination using an inactivated virus-subunit is also recommended to prevent reactivations. The profound B-cell depletion caused by CAR-T cell therapy is increasingly being considered in vaccination recommendations.In high-risk situations, antibiotic prophylaxis using fluoroquinolones can be used. However, due to increasing resistance and significant side effects, this approach is being critically evaluated.Posaconazole is recommended as the standard prophylaxis for patients with neutropenia >7 days (<0,5G/L) and hematologic malignancies. Isavuconazole offers an effective alternative for patients who cannot tolerate posaconazole. Interactions between antifungal agents and oncological therapies are becoming increasingly relevant, with particular attention to the CYP-450-enzyme inducing/inhibiting substances. Non-pharmacological measures to prevent fungal infections are now part of the recommendations. These include smoking cessation.Pharmacological prophylaxis for COVID-19 is generally not recommended.The thresholds for primary growth-factor-support have been lowered: G-CSF is generally recommended if the risk of febrile neutropenia is >20%, or, if patient inherent risk factors are present, >10%. A new long-acting, non-PEG-containing G-CSF preparation was approved in 2024.Good collaboration between oncologists and general practitioners is essential to translate these recommendations into clinical practice.