This study, published in European Urology Oncology this week, investigated the impact of antibiotic use on clinical outcomes in patients with metastatic renal cell carcinoma (RCC) treated with systemic anti-cancer drugs.
The use of antibiotics alters the microbes living in our guts (gut microbiota), which is a key regulator of immune system.
In the study, both hospital and clinical trial patients taking immunotherapy (checkpoint inhibitors or interferon) or targeted therapy (mTOR or VEGF inhibitors) were analysed. The researchers looked at the association of antibiotic use (from 8 weeks before to 4 weeks after the initiation of anti-cancer therapy) with progression-free survival and overall survival.
Patients receiving immunotherapy had worse outcomes if they were also treated with antibiotics at the start of their anti-cancer treatment. Antibiotic use appears to reduce the efficacy of immunotherapy in metastatic RCC. Changes to the gut microbiota caused by the antibiotics may have a role in optimising outcomes in patients treated with immunotherapy.