The Royal Marsden NHS Foundation Trust and The Institute of Cancer Research, London (ICR) have a long-standing record of advancing progress in gastrointestinal cancer research, and have notably had a global impact in colorectal cancer, gastro-oesophageal cancer and pancreatic cancer. The MRC Adjuvant Gastric Infusional Chemotherapy trial (MAGIC), led by Professor David Cunningham, demonstrated that giving gastro-oesophageal cancer patients peri-operative chemotherapy improved outcomes for patients, leading to a change in the standard of care in the UK and across Europe. Professor Gina Brown also led a European multi-centre trial, MERCURY, which found that MRI could be used to define and predict safe surgical margins in rectal cancer and stratify patients into different risk groups. Patients classed as ‘low-risk’ could then be spared from further treatment with chemotherapy and radiotherapy. Estimating evolution in colorectal cancer A recent study led by Professor Andrea Sottoriva, discovered that outcomes in colorectal cancer can be predicted by analysing tumour DNA in both blood and tissue biopsy samples, in addition to mathematical modelling. This combination can estimate how colorectal cancer cells change and evolve over time and could be used to assess a patient’s risk of tumour progression. Colorectal cancer is one of the most common cancers worldwide, yet outcomes for patients with late-stage disease can be poor. Understanding which patients will benefit from specific drugs and if they are at risk of their tumour progressing is therefore vital to provide personalised and adaptive treatments. Sex differences influence impact of chemotherapy Professor Cunningham and his team have also identified that the sex of a patient can impact both survival and the severity of chemotherapy side effects in upper gastrointestinal cancers. Analysis of data from four large clinical trials, which included over 3,000 patients, found that women were likely to live longer than men following treatment but would experience worse side effects such as nausea, vomiting and diarrhoea. These findings add to a growing body of evidence that sex can influence the effects of chemotherapy and that a more tailored approach to treatment and the management of side-effects may be required. Seven-gene test to predict patient outcomes Researchers at The Royal Marsden and the ICR have developed a seven-gene test which can identify gastroesophageal cancer patients at risk of relapse following chemotherapy and surgery. Currently the only way to predict the risk of progression in gastroesophageal cancer is by identifying whether the tumour has spread to the lymph nodes. This study, led by Dr Anguraj Sadanandam, analysed the DNA in over 200 gastroesophageal tumour samples collected in the MAGIC trial and found that patients can be grouped according to their risk of tumour progression. This may focus the development of future treatments and trials on those most likely to relapse. Practice changing trial in advanced anal cancer Researchers at The Royal Marsden found that a chemotherapy combination of carboplatin and paclitaxel performed better overall with anal cancer patients living seven months longer compared to chemotherapy treatment with cisplatin and 5-fluorouracil. These results led to changes in clinical practice through recommendations in European Society for Medical Oncology and National Comprehensive Cancer Network guidelines.