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[A critical consideration of the combined radiochemotherapy of head and neck tumors].

PURPOSE
Advanced tumors of the head and neck are often treated with combined radiochemotherapy. The chemotherapeutic agents used should be active in this tumor type and its adverse effects should not overlap with those of the radiation treatment.


METHODS
Published studies were reviewed and discussed on the basis of these principles.


RESULTS
Initially, single agents such as 5-fluorouracil (5-FU) and methotrexate were used in combination with radiotherapy. These combinations caused an improved local tumor control but also an increased mucosal reaction. For mitomycin C it has been shown in a randomized trial that local tumor control was improved without concomitant increased normal tissue toxicity. Also cisplatin and carboplatin were studied in combination with radiotherapy. Unfortunately, there are no results of randomized studies available but these agents do not seem to increase mucosal toxicity. The standard chemotherapy of squamous cell carcinomas of the head and neck is cisplatin and 5-FU. Many studies have been conducted with this chemotherapy in combination with radiotherapy. To this day it has not been shown that the results of an effective radiation treatment or an effective chemotherapy can be improved by these experiments. The explanation for that is that either the chemotherapy or the radiotherapy cannot be given at full dose because the regimen would become too toxic.


CONCLUSION
5-FU containing polychemotherapy regimens should not be combined with radiation any more because it is known that 5-FU increases the mucosal reaction. Agents that could be studied in the future either alone or in combination with cisplatin or carboplatin are etoposide and taxol.