A STUDY has found that overall survival for patients with metastatic pancreatic ductal adenocarcinoma (PDAC) is improved with the use of perichemotherapy antibiotics. PDAC generally has poor outcomes for patients, partly due to multifactorial resistance to the chemotherapy offered as treatment. Receiving antibiotics 1 month pre- or post-gemcitabine treatment was found to correlate with overall survival rates, but similar results were not found after treatment with fluorouracil.
Carried out by the Henry D. Janowitz Division of Gastroenterology, Icahn School of Medicine at Mount Sinai, New York, USA, the study used the Surveillance, Epidemiology, and End-Results database, which is population-based and linked to Medicare (Lawrence, Kansas, USA). The survival outcomes of 3,850 patients with primary metastatic PDAC were analysed (mean age: 74.2 years; 45.4% male). In this cohort, 81.8% were treated with first-line gemcitabine and 18.2% with fluorouracil chemotherapy. Antibiotics were given to 56.6% of these patients, who were matched to those who did not receive antibiotics; thus, researchers reviewed 1,672 matched pairs.
Among the patient cohort given perichemotherapy antibiotics, median survival rates were 7.3 months (95% confidence interval [CI]: 6.9–7.7) compared to 6.8 months for the group who did not receive antibiotic treatment (95% CI: 6.5–7.2). Median survival for those receiving gemcitabine was 7.1 months (95% CI: 6.8–7.5) in the antibiotic group versus 6.5 months in the non-antibiotic group (95% CI: 6.2–6.8), and for fluorouracil 8.6 months (95% CI: 7.3–9.7) versus 9.2 months (95% CI: 8.3–10.1) in the antibiotic and non-antibiotic group, respectively. Researchers commented that patients receiving perichemotherapy antibiotics had improved overall survival (hazard ratio [HR]: 0.93; 95% CI: 0.86–0.99); for those on gemcitabine there was an 11% improved survival rate (HR: 0.89; 95% CI: 0.83–0.96). However, no association between antibiotic use with fluorouracil treatment and overall survival was found (HR: 1.08; 95% CI: 0.9–1.29).
Study author Daniel J. Fulop, Icahn School of Medicine at Mount Sinai, commented: “Small retrospective studies of patients with PDAC have found associations between antibiotic exposure and improved treatment outcomes, particularly among patients receiving gemcitabine. Collectively, these studies suggest that antibiotics may affect outcomes in patients with PDAC.”
