Antibiotic use and survival from breast cancer

What is the aim of the study? What do we plan to do?
Our primary objective is to compare the survival experience of breast cancer patients who frequently use antibiotics to the survival experience of breast cancer patients who do not frequently use antibiotics. This analysis will be based upon data from the medical records of breast cancer patients from England. We will identify breast cancer patients from cancer registry records and we will identify death from national mortality records. We will determine antibiotic use in these patients from General Practice prescriptions. In our analysis we will account for other characteristics of breast cancer patients including age, year, stage, grade, cancer treatments and other medical conditions.

Why is this important? What are the potential patient benefits?
In the UK it is estimated that over 1 million women will be living with a diagnosis of breast cancer by 2030. Antibiotics are commonly used to treat infections in breast cancer patients. Recent animal studies have suggested a possible link between antibiotic use and the speed of breast cancer growth. It is important to investigate antibiotics and survival from breast cancer to provide information to breast cancer patients and clinicians on the potential association between antibiotics and breast-cancer specific mortality.

When will the research be conducted?
The analysis of medical records will take place during 2023 to 2026.

Who are the research team?
The research team consists of academics from Queen’s University Belfast, University of Oxford and University of Nottingham. The team contains expertise in General Practice, breast cancer surgery, pharmacy, and statistics.

GP data will be used to identify the main exposure prescribed antibiotic use. GP data will also be used to identify potential confounding factors including age, comorbidities, other medication use, BMI and smoking.

HES data will be used to identify cancer treatments, in-hospital infections and comorbidities.

Mortality data including date and causes of death will be used to identify the primary outcome death from breast cancer (defined as breast cancer as the the primary cause of death).

Cancer registry data will be used to identify breast cancer patients. Cancer registry data will also be used to identify prognostic factors such as stage, grade and specific cancer treatments.

Professor Julia Hippisley-Cox - University of Oxford

Professor Carol Coupland - University of Nottingham

Dr Blánaid Hicks - Queen's University of Belfast 

Dr Úna Mc Menamin - Queen's University of Belfast 

Mr Stuart McIntosh - Queen's University of Belfast