Study design and participants
A parallel randomized controlled, open label pilot trial was conducted. This trial is registred at CinicalTrials.gov: NCT05237921 and conforms to CONSORT guidelines for randomized controlled trials. Study protocol is available online www.clinicaltrials.gov. Recruitment was conducted at the Oncology center of Hospital Beatriz Ângelo and patients were consecutively selected by Oncologists during the weekly multidisciplinary meeting. Patients with esophageal, gastric, pancreatic and rectal cancer, were enrolled at diagnosis provided that they were eligible for neo-adjuvant chemo/radiotherapy (ChT) and with age higher than 18 years and lower than 80 years. Before enrollment initiation, besides upper gastrointestinal cancer (as initially planned for), we decided to also include patients with rectal cancer to have a broader view of adherence to CEDI in patients with gastrointestinal cancer under neo-adjuvant treatment, which is in line with the exploratory nature of this study.
Combined Dietary and Exercise Intervention arm
The intervention group received a supervised combined moderate aerobic and resistance training, once a week with duration of 40-60 minutes plus daily home exercise. All patients were evaluated in respect to their physical condition by a physical medicine and rehabilitation physician, and exercise was administered by a physiotherapist. Exercise was planned within a “slow and low“ approach and was personalized according to patients’ age and functional status. The first exercise session was dedicated to full patient evaluation in order to perceive patients individual tolerance and to educate in regard to home exercises. Most common exercises were aerobic exercises as 10-15 minutes of walking and resistance exercises as squatting with theraband around knees, shoulder flexor strengthening in standing using theraband and stretching. Educational written and illustrated materials as well as therabands were provided to each patient for home based exercise.
Besides exercise, the intervention group received a one-on-one nutritional counseling, by a senior and research Dietitian (SV). In the first visit a dietary plan was designed and one daily oral nutritional supplement (Forticare®, Nutricia) was given to meet the European Society of Parenteral and Enteral Nutrition (ESPEN) recommended intake of 25-30kcal/kg/day and 1-1.5g of protein/kg/day [25] . Also, patients were recommended to maintain a fat intake of 30% of total daily calories, with mostly being provided by monounsaturated fat. Patients were suggested to drink the supplements after exercise. All dietary plans were created with Nutrium® software, in order to obtain personalized dietary plan prescriptions that conveyed nutritional needs targets. Nutrium is a Portuguese software that allows rigorous dietary planning, since it enables the user to set energy and nutrient estimated requirements and to create dietary plans with nutritional composition information determined for Portuguese foodstuffs [26] . Written materials were given to patients and/or caregivers. Follow up visits took place every week during exercise.
Total duration of the intervention was set at 8 weeks, although patients with longer neo-adjuvant treatments, namely patients with rectal cancer, maintained the intervention for a longer period of time, with a maximum of 12 weeks. Patients were recommended to maintain the dietary plan and exercise during the whole ChT treatment plan. Due to possible symptoms after ChT, namely nausea and vomiting, patients were asked to intensify compliance on the week preceding ChT when there is a higher probability that patients are less symptomatic. Whenever patients did not attend the weekly exercise activity, they were contacted to provide support and to assess if any diet or exercise adjustment was needed in order to maximize adherence.
Control arm- Standard care:
Patients allocated to the control arm received standard care, in which patients were referred to the dietitian only when the attending physicians felt there was a need for dietary intervention. Whenever relevant, exercise was recommended but without personalized training program, according to our current practice.
Outcome measures
The primary outcome was intervention adherence, that was evaluated according to five criteria: 1) proportion of patients willing to engage in CEDI; 2) adherence to dietary plan, patients were considered adherent if they have met ≥ 75% of their calorie and protein estimated requirements; 3) adherence to oral nutritional supplements, one supplement per day was prescribed, and supplement intake ≥ 4 weeks was considered acceptable; 4) adherence to exercise, were attendance to the exercise class for at least 4 consecutive weeks was considered acceptable; 5)adherence to CEDI, patients were considered adherent if they were able to meet more than 75% of their calorie and protein estimated requirements/oral nutritional supplementation and adhered to exercise, approximately one month after initiation of CEDI. Dropout rates and reasons for leaving the study were also recorded.
The secondary outcomes included change in weight, waist circumference, CT derived body composition and functional status assessed with hand grip strength, 6MWT and functional score of EORTC quality of life questionnaire. Measurements were conducted before and after neo-adjuvant treatment.
Sample size
Sample size per group was calculated bearing in mind that according to data form the World Health Organization, 14% of Portuguese adults are compliant to moderate exercise, and in our study adherence will be set as compliance ≥ 50%. Considering a power of 0.80 and an α set at 0.05, 25 patients will be needed per group. A planned interim analysis was performed to substantiate preparation of further study protocols using CEDI, and results are reported in this paper.
Randomization
A table was created by a web based randomization system to allocate treatments, with an allocation ratio of 1:1. Stratified block randomization using random block size (2, 4 and 6) was conducted to allocate patients to standard care and to intervention with CEDI. Stratification was performed according to disease location. Patients eligible to enter the study were referred by Oncologists, and after obtaining consent patients were enrolled in the study by researcher (SV), which was responsible for allocation consignment.
Procedures
Clinical data
Demographic and clinical data as age, gender, tumor site, histological type, TNM staging, ChT toxicity, overall survival were prospectively recorded and retrieved from electronic records. ChT toxicity was graded according to National Cancer Institute Common Toxicity Criteria. Dose-limiting toxicity (DLT) was defined as any grade 3/4 toxicity associated with physician-ordered dose reduction or termination of therapy and ChT delay. This data was collected by Oncologists. The most common neoadjuvant treatments were: FLOT (5-Fluorouracil, Folinic acid, Oxaliplatin, Docetaxel) for gastric, XELOX (Oxaliplatine and Capecitabine) followed by Capecitabine plus radiotherapy for rectal, Carboplatine/Paclitaxel and radiotherapy for esophagus and FOLFIRINOX (5-Fluorouracil, Irinotecan and Oxaliplatin) for pancreatic cancer patients. Duration of neo-adjuvant therapies varied from 8 to 12 wks.
Anthropometric measures and nutritional assessment
Anthropometric measures (AM) such as weight and height were obtained, and Body Mass Index was calculated. All AM were performed according to previously established protocols [27] . Patient Generated Subjective Global Assessment (PG-SGA) was conducted by an experienced dietitian and patients were classified as well nourished (SGA A), moderately or suspected of being malnourished (SGA B) or severely malnourished (SGA C). Assessments were conducted before and after neo-adjuvant treatments.
Body composition assessment
Cross-sectional imaging evaluation
Body composition analysis was conducted with Computed Tomography (CT) scan image analysis [5] . Images were selected at the third lumbar vertebra (L3) using a portal venous phase. CT scans were used opportunistically, as CT is performed at diagnosis and after neo-adjuvant treatment. Image thickness was 5mm and tube voltage was 100kv. Images were processed with Slice-o-Matic (Tomovison) and ABCS module that performs automatic segmentation of tissue cross-sectional areas, whereas posterior validation of image processing was done by the Radiologist, with manual corrections as necessary. Segmentation of tissue cross-sectional areas was conducted according to the following Hounsfield unit thresholds: -29 to 150 for skeletal muscle, -190 to -30 for subcutaneous and intramuscular adipose tissue, and -50 to -150 for visceral adipose tissue. Cross-sectional skeletal muscle, visceral fat, and subcutaneous fat was recorded in squared centimeters and mean muscle radiation attenuation in Hounsfield units. Skeletal muscle area (SMA) was normalized for stature to calculate the skeletal muscle index (SMI) - cm2/m2. Sarcopenia was defined as SMI lower than 41 cm2/m2 in women, lower than 43 cm2/m2 in men with body mass index (BMI) <25 Kg/m2 and lower than 53 in men with BMI > 25 Kg/m2 as described by Martin et al [5] . Visceral obesity was defined as visceral fat area >130cm2 [28] . An inter-reliability analysis was conducted and variance coefficients computed for two duplicate CT scans was 0.32%, 1.09%, 0.39% and 4.04%, for skeletal muscle, visceral adipose tissue, subcutaneous adipose tissue and intramuscular adipose tissue areas, respectively.
Dietary Intake assessment
Dietary intake was assessed with a Semi-quantitative Food frequency questionnaire to estimate dietary intake of both the intervention and control group before and after neo-adjuvant therapy and 24h recalls to assess dietary intake of patients undergoing CEDI at every 2 weeks in order to estimate compliance to established dietary goals.
The Semi-quantitative Food Frequency Questionnaire (FFQ) used was developed for the Portuguese population [29] and is designed to evaluate usual dietary intake. This questionnaire includes 86 commonly-eaten food or drinks and participants were asked to estimate the amount and frequency of intake of each food/drink according to frequency and amount at baseline and before surgery. Conversion of foodstuffs to nutrients was conducted with software Food Processor Plus (ESHA Research, Salem, Oregon) which has been adapted to the Portuguese commonly-eaten food or drinks.
The 24h recall using a modified USDA five-pass method consists in 5 steps where the first is to list all foods consumed on the previous 24h. On the second step the interviewer asks about possible forgotten food items. In the third step the interviewer clarifies the time and occasion of the consumed foods and on the fourth step clarifies portion size [30] . Conversion of foodstuffs to nutrients was conducted with Nutrium® software which has been developed for the Portuguese population [26] .
Functional status assessment
Performance Status was assessed with Eastern Cooperative Oncology Group Performance Status scale. According to these criteria patients are classified from grade 0 (fully active) to grade 4 (bedridden). Prior to initiation and after neo-adjuvant treatment a 6 min walk test (6MWT) was conducted by cardiopulmonary technicians blinded to the intervention groups, were walking distance and percentage of predicted normal values were recorded.
Handgrip strength was measured with a dynamometer (JAMAR®) and measurements were recorded in kg. Handgrip strength was measured 3 times with the non-dominant arm according to manufacturer’s instructions. Mean handgrip strength was analyzed with gender specific thresholds from the revised guidelines of the European Working Group on Sarcopenia in Older People (EWGSOP) (<27kg in men and <16kg in women) [31] .
Patient Reported Outcome Measures
Quality of life was assessed before and after neo-adjuvant treatment with the European Organization for Research and Treatment of Cancer (EORTC) questionnaire. This questionnaire allows determination of functional, symptoms and overall quality of life score.
Statistical analysis:
Adherence to CEDI was analyzed with an intention to treat approach, whereas anthropometric measures, body composition, functional status, quality of life and dietary intake were analyzed with a per protocol approach. Continuous variables were described as median and inter-quartile range, while categorical variables were expressed as frequency and percentage. Chi-square test or Fisher exact test were used to assess association between categorical variables. Differences in means from continuous variables were analyzed by t-test or Mann Whitney U test as appropriate, according to variables’ adjustment to a normal distribution. Shapiro-Wilk test was used to test for normality. Effect size was computed with Cohen’s d for t tests and r for Mann-Whitney U tests. Paired-samples t test or Wilcoxon Signed Rank Test were used to analyze longitudinal data within the control and intervention arm. Statistical analysis was conducted with R Studio Version 1.2.5042 software.