Colorectal cancer is the second most common cancer in Norway with 4332 new cases in 2017. Standard of care is radical surgery followed by adjuvant chemotherapy for some, depending on the stage of the disease. Most commonly, a combination of Oxaliplatin and Capecitabine or 5-fluorouracil is given for 3 to 6 months.
A common side effect of Oxaliplatin is peripheral sensory neuropathy, which occur in different degree in over 90 % of the patients. There is no established treatment to prevent or reduce Oxaliplatin induced peripheral neuropathy. A few minor studies have been published indicating that physical activity can reduce the patient's experience of chemotherapy-induced peripheral neuropathy.
Most patients receiving chemotherapy will experience fatigue in some degree. It has been shown in several studies that exercise can reduce cancer related fatigue, though most studies have been performed among women with breast cancer.
There are a limited number of randomized controlled clinical trials looking at the effects of physical exercise during ongoing adjuvant chemotherapy in colorectal cancer patients. Thus, there is a clear need for further studies on physical exercise in this patient group.
In the period from January 2017 to November 2018 the investigators did a non-randomized pilot study to test the feasibility of the exercise intervention in this patient group, and to calculate sample size for the randomized trial.
The 9-item European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire (QLQ) Chemotherapy Induced Peripheral Neuropathy (CIPN20) sensory subscale will be used to measure peripheral sensory neuropathy. Each item is rated on a scale from 1 ("not at all") to 4 ("very much"), and the total raw score ranges from 9 to 36. The raw scores will be linearly transformed to a 0 to 100 scale (higher scores represent worse CIPN severity). A difference of 10 is considered clinically significant. The sample size calculation is based on a two-sided t-test. Aim is to demonstrate a difference in patient-reported sensory peripheral neuropathy between the two groups 3 months after randomization. It is postulated that the intervention group develops less degree of peripheral sensory neuropathy than the control group. Based on the answers obtained from the questionnaire in the pilot study, a standard deviation (SD) of 12.5 is assumed for the change between baseline and 3 months. To detect a difference of 10 with a strength of 80% and with a significance level of 0.05, there should be 25 patients in each arm. A drop out of 20% is taken into account based on experience in the pilot study. This suggests that 64 patients should be included in this study.
Patients scheduled for adjuvant Oxaliplatin based combination chemotherapy will be recruited from cancer clinics in Norway, and randomized to an intervention group or a control group. Before randomization and start of the first cycle of chemotherapy, the study participants will perform baseline testing and fill in the different questionnaires.
The intervention with exercise training starts around the same time as adjuvant chemotherapy starts, usually 4 -6 weeks postoperatively, and lasts as long as the adjuvant treatment, i.e. 3 - 6 months. Participants start with an individual session with a physiotherapist at the hospital. A treadmill submaximal heart rate test is done to give the participants instructions regarding the recommended intensity zones during cardio training.
The exercise intervention consists of three components: sensorimotor training (SMT), strength exercises, and aerobic training. The SMT and strength exercises are carried out twice a week as guided training together with the physiotherapist, each session lasting 30 minutes. In addition, instruction is given to do minimum 90 minutes a week of moderate intensity (60 - 75 % of maximum heart rate) home-based aerobic training, or 45 minutes with high intensity (80 - 85 % of maximum heart rate) aerobic training.
Participants in the intervention group receive a pulse watch to guide the intensity of the aerobic exercise. The participants will register completed training in a training log. Based on previous experience with physical activity and exercise, individual guidance is provided.
Once a month participants will fill out the form, Patient-Generated Subjective Global Assessment Short Form (PG-SGA SF), and will be referred to a nutritionist if the score is 2 or higher. Regardless of the score on this form and group affiliation, participants may be referred to a nutritionist based on clinical judgment.
In the pilot study, also a qualitative study was carried out with semi-structured interviews evaluating patient's expectations and experiences regarding the physical exercise training. Depending on the information power obtained in the current sample, additional interviews of patients in this randomized trial might be done.
