METHODS
This prospective cohort study included patients with colon or rectal
cancer who were scheduled to undergo surgery. Only patients who provided
informed consent were allowed to participate. The institutional review
boards of the participating hospitals approved the study, and all study
data were kept confidential. A detailed description of the study
protocol has been published previously.3
Patients were eligible for this study if they were on the surgical
waiting list of one of the participating hospitals and had a diagnosis
of surgically resectable colon or rectal cancer. The exclusion criteria
were in situ cancer, an unresectable tumor, terminal disease, and
inability to respond to questionnaires for any reason or any severe
mental or physical conditions that might prevent the patient from
responding to questionnaires, as well as a lack of consent to
participate.
Data collection
Data collected at hospital admission included sociodemographic and
clinical data, including information about comorbidities based on the
Charlson Comorbidity Index 4), preoperative data,
pathology data including TNM stage and infiltrated lymph nodes, and data
related to the period of admission after surgery. Data were collected at
1, 2, 3 and 5 years after surgery. The information collected at those
points in time included the need for radiation therapy and/or
chemotherapy, performance of CT scanning, colonoscopy, laboratory test
results, diagnostic tests performed, any complications, tumor
recurrence, readmission or reoperation, and death.
Patients completed the following questionnaires before surgery and at 1,
2, 3 and 5 years after surgery: the Hospital Anxiety and Depression
Scale (HADS) 5, the EuroQol-5D (EQ-5D)6, and the European Organisation for Research and
Treatment of Cancer (EORTC) QLQ-Q30 7. The HADS is a
screening tool for anxiety and depression in nonpsychiatric clinical
populations 8. The EQ-5D is a generic health-related
quality of life (HRQoL) questionnaire that has good psychometric
properties. It allows comparison with other populations, as well as
re-evaluations 9. The EORTC QLQ-C30 is a questionnaire
for evaluating the HRQoL of cancer patients undergoing treatment.
The main outcomes of the study were mortality, complications (as defined
elsewhere 3) and tumor recurrence, all at 1, 2, 3 and
5 years, and patient-reported outcomes (changes in the EQ-5D, EORTC
QLQ-C30, and HADS scores from baseline to 1, 2, 3 and 5 years after the
intervention). The main independent variables included were CT scanning,
colonoscopy, chemotherapy and radiotherapy performed at each time point.