The objective of this small study is to assess the feasibility of remotely delivering a diet and lifestyle intervention following treatment of CRC through telecommunications and digital technology. A DBCI will be implemented among a population of people living with and beyond CRC to help identify if patients find this an easy and achievable way to communicate with a Registered Dietitian. The information gained from this small scale feasibility will be used to help develop a larger study on supporting people with CRC to make a lifestyle change.

Fifty four percent of Colorectal cancer (CRC) cases are thought to be preventable, showing it has a strong correlation with lifestyle factors. A recent report by the World Cancer Research Fund and American Institute of Cancer Research (WCRF/AICR) on diet, physical activity (PA) and CRC reported numerous findings linking lifestyle with primary prevention of CRC. Approximately six out of ten people diagnosed with bowel cancer in England and Wales survive for 10-years or more and rates of survival have more than doubled in the last 40-years.

The term 'cancer survivors' denotes all people who are living with a diagnosis of cancer, and those who have recovered from the disease. The term is not universally accepted and survivors are increasingly being referred to as people 'living with and beyond cancer. This covers a wide variety of circumstances including people at diagnosis, during and post treatment, and those with recurrence therefore including people with potentially differing nutritional needs. People can be struggling with a poor nutritional intake due to treatment side effects or may need to optimise their nutritional status preoperatively or require advice post treatment for optimum recovery and rehabilitation. However, compared to the vast amount of research with respect to CRC incidence there is a paucity of research on diet and lifestyle factors influencing CRC recurrence and survival.

The second WCRF and AICR expert report in 2007 undertook a systematic literature review to assess the role of food, nutrition and PA in people diagnosed with cancer. The report included randomized control trials (RCTs) evaluating dietary interventions, however, there were no conclusions drawn. This was attributed to poor quality designs and varying intervention duration of the studies. The third WCRF and AICR expert report, in 2018, stated new evidence had accrued since the second report but primarily within breast cancer therefore a review of the evidence was undertaken in this group leaving a gap in the evidence base with regard to CRC.

The design of secondary prevention studies are based on expert conclusion with the third WCRF recommending survivors who have completed treatment should follow the general advice for cancer prevention. The current strongest primary prevention evidence is that CRC risk is decreased by being physically active in addition to a higher consumption of wholegrains, dietary fibre and dairy products. Risk is increased by the consumption of red and processed meat, more than two alcoholic drinks per day and being overweight or obese.

A recent review of the literature of lifestyle interventions in RCTs in people with CRC has identified 6 published studies (in preparation). The review identified that all current studies used a variety of dietary and physical activity interventions, data collection tools and inconsistent timing of interventions commencing from 6 months to 5 years post diagnosis. None of the published RCTs achieved changes in dietary intake and any small changes that occurred were not sustainable with participants reverting to their usual dietary habits.

One conclusion from the review was that no studies used appropriate methods to support behaviour change such as healthcare professionals trained in behaviour change techniques and methods of support, for example, digital technology. It has been demonstrated that such techniques would help support people to make lifestyle changes and from a research perspective can eliminate administration-intensive tasks, variation in interpretation and recording errors

Discussion with the PPI group of The Royal Marsden Hospital (NHS Foundation Trust) and Institute of Cancer Research provided a valuable insight into the variance in opinion as to when and how people could be asked to make lifestyle changes. The support provided by family members and / or carers was identified as a critical factor in supporting people to make lifestyle changes.

There has recently been an increased interest in the use of digital behaviour change interventions (DBCIs) and smartphone applications in the healthcare setting, including in the management of diet, PA and weight.

A recent systematic review of DBCIs amongst cancer survivors identified fifteen studies and concluded DBCIs can improve PA and Body Mass Index (BMI), in this patient group, with mixed results for improved dietary behaviours.

Inclusion Criteria:

1. All adult outpatients, over the age of 18, under The Royal Marsden NHS Foundation Trust with a formal diagnosis of stage I-III CRC.
2. Participants must have completed treatment for CRC (defined as 3 weeks after stopping chemotherapy) and own a smart phone.

Exclusion Criteria:

1. Patients who have metastatic disease
2. Patients who have experienced a significant weight loss >10% body weight in past 3 months as they are at risk of malnutrition and will be referred to the dietitians for advice beyond healthy living and diet advice.
3. Patients with a BMI >35 kg/m2
4. People with a prior formal diagnosis of memory impairment
5. Patients who cannot read or write English