[Principles of oncologic drug therapy following surgery for bowel cancer]

Adjuvant chemotherapy for 6 months following curative resection of colorectal cancer (CRC) reduces recurrence risk and improves survival in lymph node positive, stage III disease. In stage II CRC the benefit of adjuvant chemotherapy is smaller and only recommended if high risk prognostic factors are present. Microsatellite instability in stage II CRC is associated with a favourable prognosis and when present adjuvant chemotherapy is not needed. Adjuvant chemotherapy improves disease outcome also in elderly patients (≥ 70 years) with stage III CRC, but is not recommended in stage II disease. Adjuvant chemotherapy should be started within 8 weeks following surgery.