A Longitudinal Investigation of Cognitive Function in Colorectal Cancer Patients

Inclusion Criteria: * Aged 18-70 years old * Performance Status (PS) of 0-1 on the ECOG Performance Scale * Life expectancy of at least 12 months * Full recovery from any post operative sequelae * Adequate hepatic function as documented by a serum bilirubin \< 18umol/L, and LFTs within 1.5X normal range * Patients with histologically confirmed, stage B or C colorectal cancer (CRC), who have undergone surgical resection and are about to commence chemotherapy. * Patients due to receive neoadjuvant chemotherapy prior to surgery are also eligible. Exclusion Criteria: * Any major pre-existing psychiatric history or dementia, alcohol abuse, or currently using a psychotropic medication that might lead to cognitive problems, other than short acting benzodiazepines for nausea or sleep * Any evidence of metastatic disease. If there is clinical suspicion of CNS involvement patients must have brain imaging (MRI or CT scan) prior to recruitment. * Ongoing sepsis or uncontrolled infection, including HIV infection * Pre-existing neurological condition likely to interfere with ability to perform cognitive testing * Any other severe co-morbidity which, in the judgement of the investigator, would make the patient inappropriate for entry into this study * Active cancer within the last 5 years other than squamous or basal cell carcinoma of the skin or cervical cancer in situ (except for CRC) * Previous history of chemotherapy * Minimal English skills such that subjects would be unable to follow simple, written English instructions and to read questionnaires of a grade 8 standard with the help of a research assistant.