[Continuous radiosensitizing chemotherapy]

Concomitant use of radiation therapy and chemotherapy is increasing steadily in the treatment of locally-advanced epithelial tumors. This approach has been proved effective in head and neck, esophageal, and canal and nonsmall-cell lung cancers. One of the best radiation sensitizers known to date is 5FU. In vitro cell model have demonstrated the importance of continuous exposure to the drug during 12 to 24 hours after the radiation session. These biological data have been confirmed by a randomized study in rectal cancer comparing 5FU bolus therapy versus 5FU given continuously during irradiation. Disease-free survival and overall survival were longer in the continuous infusion group. Cisplatin is being increasingly used in moderate but repeated doses, a regimen that requires central venous access. Similarly, etoposide, whose venotoxicity is well known, is an excellent radiation sensitizer that is gaining ground, most notably in the treatment of lung cancer. Nutritional support is a key component of all radiochemotherapy regimens used to treat digestive tract cancers and usually requires parenteral nutrition via a central venous access.