Colorectal carcinoma - Recent aspects of chemotherapy

Despite growing prevention programs colorectal carcinoma is the second most common malignant disease after lung cancer. Approximately every second pat ient will die due to its metastatic disease. While surgical resection of th e primary tumor is widely accepted, palliative treatment of colorectal meta stases, primarily based on 5-fluorouracil (5-FU), is still under debate. Re gimens with 5-FU and its biomodulation by folinic acid showed relatively lo w remission rates and short prolongation of survival. Recently, a number of new promising antineoplastic agents have entered the field. At the meeting of the "American Society of Clinical Oncology", May 15th-19th 1998 in Los Angeles, these agents were investigated in phase II and III studies. A spec ific inhibitor of the thymidilate synthetase, raltitrexed, showed comparabl e antineoplastic activity to 5-FU with a convenient three-weekly schedule a nd low side effects. Oxaliplatin, a platinum-II-complex, had been introduce d into therapeutic 5-FU regimens for first- and second-line treatment. Irin otecan, a new topoisomerase-I-inhibitor, had considerable antitumor efficac y and better survival compared with best supportive care in 5-FU pretreated patients. Furthermore, combinations of these drugs are promising therapeut ic options for patients who develop resistance to 5-FU. The exact role of t hese new substances in the second-line treatment of metastatic colorectal c arcinoma has further to be clarified.