Advances in Adjuvant Treatment of Resectable Disease
Peri-operative Treatment of Colon Cancer
For patients with high risk stage II and III, adjuvant chemotherapy with 5FU/oxaliplatin has become standard. Treatment should start within 5 6 weeks after surgery and should be given for six months. Combination chemotherapy is preferred over singleagent 5FU since the relapse rate is significantly improved by the addition of oxaliplatin with acceptable short and long-term toxicity. Since a relapse in this disease mostly means an incurable situation, this event should be avoided as much as possible and combination chemotherapy should be preferred for most patients, as well as for older patients. Patients with stage II disease lacking risk factors (e.g. obstruction, perforation, less than 12 lymph nodes resected, poor grading) also might benefit from adjuvant chemotherapy, at least single agent 5FU as shown in the British QUASAR trial. Despite these data, the decision for adjuvant treatment in stage II disease without high risk features can be decided on an individual basis.
Several prognostic factors have been investigated; however, currently none of them form the basis for individual selection of patients for specific adjuvant treatment modalities. These factors include loss of heterozygosis, chromosome 18q, microsatellite stability or instability, insulin-like growth factor-?- receptor type II, excision repair cross-complementing rodent repair deficiency, complementation group 1 (ERCC1), etc. None of these markers should be currently used as argument for or against adjuvant chemotherapy outside clinical trials.