Strategies to improve prevention and treatment of colorectal cancer

This thesis consists of two parts. In the first part, we investigated current practices with regard to the identification of young patients with colorectal cancer potentially due to hereditary disease as well as measures to improve its detection. We found that compliance with guidelines for hereditary colon cancer screening was low. Also, we found that a paper-based family history questionnaire, sent to patients before undergoing a colonoscopy, was returned by only one-third of patients.

In the second part of this thesis, we looked at the treatment of early colorectal cancer. We found that approximately 90% of cancers that arise shortly after a colonoscopy with resection of a polyp, may have been prevented by an adequate endoscopic resection and follow-up. This underlines the importance of performing a high-quality colonoscopy. We also investigated which patients with early colorectal cancer may benefit from only a colonoscopic resection, with no additional surgical resection. Whether this is indeed indicated can usually only be determined after colonoscopic resection of the early lesion. We found that a colonoscopic resection of early colon cancer, prior to surgical resection, does not have a negative effect on patients’ outcomes compared with immediate surgical resection. Furthermore, we found that patients with early colorectal cancers in a polyp with a stalk have a better outcome than the ones without a stalk.

We conclude that recognition of hereditary forms of colon cancer as well as diagnosis and treatment of early colorectal cancer needs further improvement.