Colorectal carcinoma: current problems and future perspectives.

Colorectal carcinoma represents a highly interesting model for the biological development of a solid tumor, the efficacy or primary and secondary prevention and the development of chemotherapeutic and immunologic strategies for adjuvant and/or neoadjuvant treatment is resectable stages. Adjuvant systemic 5-FU/levamisole is currently the standard adjuvant treatment for stage III colon cancer. 5-FU/folinic acid for 6 months seems to achieve equivalent results. Continuous infusion of 5-FU for 7 days postoperatively via the portal vein achieves also a comparable improvement in disease-free and overall survival. Beyond the long term systemic as well as short time intraportal chemotherapy, adjuvant immunotherapy with either 17-1A murine monoclonal antibody or autologous tumor vaccine achieves quite comparable results like adjuvant chemotherapy. Therefore the combination of these modalities might be of high interest for further investigation. The current EORTC study for colorectal cancer investigates the role of the combination of short time regional and long term systemic chemotherapy. For rectal cancer stage II and III adjuvant 5-FU plus radiation is currently the standard. However, further improvement seems possible with 5-FU given as continuous infusion during radiation; this approach is currently investigated in an ongoing Intergroup study. A further attractive approach, particularly for locally advanced, borderline resectable rectal cancer is the neoadjuvant combined modality treatment with 5-FU/folinic acid plus radiation followed by surgery and further adjuvant chemotherapy; this neoadjuvant treatment is currently being investigated in comparison to postoperative 5-FU/folinic acid plus radiation in an ongoing Intergroup study. Future protocols should also include immunotherapy with 17-1A antibody which significantly prolongs disease-free and overall survival also in rectal cancer.(ABSTRACT TRUNCATED AT 250 WORDS)