GO ctDNA – Gastroesophageal Cancer ctDNA Study

Brief description:

Circulating tumour DNA (ctDNA) is a highly specific method to detect cancer. It is based on the detection of short fragments of tumour-derived DNA mutations in the bloodstream. In principle, a blood ctDNA sample could be used to assess a person’s entire tumour burden without the need for biopsy. This may provide timely information on drug targets and how/whether the tumour is responding to treatment. Intensive monitoring of the tumour during chemotherapy may help guide which drugs to use throughout the course of a person’s treatment, and when to stop drugs or treatment that are not working.

This pilot study will determine if ctDNA is likely to be a useful tool to monitor treatment response in people with gastroesophageal cancer who are undergoing treatment that includes chemotherapy (FLOT) or chemoradiotherapy (CROSS). If successful, a randomised controlled trial of ctDNA monitoring to direct the use of chemotherapy and other treatments for gastroesophageal cancer may be undertaken.

Up to 30 participants will have a blood sample taken for ctDNA analysis, prior to each infusion of chemotherapy, whether combined with radiotherapy or not. Samples will collected before surgery and if applicable, prior to chemotherapy after surgery. Participants will be also followed up at (i) 4-6 weeks and (ii) 3-6 months following treatment completion. All blood samples are taken at routine visits. Permission to access hospital medical records and any stored cancer tumour tissue will be sought.