Patient-associated risk factors

Elderly (>65)

Female

Genetic polymorphisms affecting drug metabolism and distribution such as Gilbert’s syndrome, Crigler-Najjar syndrome

Biliary obstruction

Associated bowel pathology such as inflammatory bowel disease or malabsorption

Treatment-associated risk factors

Irinotecan & 5-FU

Weekly chemotherapy schedule

Infusional chemotherapy

Bolus 5-FU

Prior history of CID

Prior or concomitant radiotherapy