Do Chemotherapy Dose-delays impact Patient treatment Outcomes?

Background Chemotherapy is administered to patients in treatment cycles, allowing for a rest period between doses. Rest periods allow a patient to recover from adverse effects (AEs) of anticancer therapy such as myelosuppression.

Delays to chemotherapy doses occur in around ten percent of patients when AEs are still present at the time of administration; however, some of these could be prevented by the use of supportive care medicines.

Policies around supportive care used to prevent AEs differ from hospital to hospital in the United Kingdom and this may have an impact on treatment delays.

Delays to treatment can be up to 7 days or occasionally longer; yet, it is unclear the impact of the delay on time to cancer progression for a patient.

Aims and Objectives The ultimate aim of this research is to optimise the first chemotherapy treatment course for patients with early stage breast and ovarian cancer. This will be achieved by determining the impact of dose delays to progression free survival or death.

If a difference exists then we will investigate the influence of other factors such as region treated on the incidence of dose delays. Methods To achieve the objectives we will use three datasets collected by NHS England. These datasets contain cancer diagnosis information, detailed chemotherapy information and data on death.

Data will be linked to enable us to develop Cox regression model, using an outcome as 5-year progression free survival or death. We will report proportional hazard ratios for dose delays as well as other confounders.

Timelines for Delivery This research will be achieved in 18 months Impact and Dissemination This study will have impact on the chemotherapy service and for patients.

The understanding the research provides could be a goad to better AE management and will be the first real world study to demonstrate the impact of delaying chemotherapy doses. We believe that this will not only change UK practice in prescribing practices but also international policies.

Following this work we will engage with both patients and clinicians through the cancer alliances to understand if and how policies around prescribing supportive treatments vary and how equitable access can be achieved. We will communicate the work to the UK Chemotherapy board and publish in a high impact journal.