Elapsed radiation therapy treatment time as a predictor of survival in patients with advanced head and neck cancer who receive chemotherapy and radiation therapy.

PURPOSE: To determine whether elapsed radiation therapy treatment time relates to survival in patients with head and neck cancer treated sequentially with chemotherapy and radiation therapy.
MATERIALS AND METHODS: From 1981 to 1988, 76 adult patients with bulky stage II-IV head and neck cancer received induction chemotherapy (fluorouracil and cisplatin). Those with a complete or partial response (n = 46) received full-dose definitive radiation therapy (range, 64.0-77.5 Gy; median, 70 Gy). Those with less than a partial response (n = 21) underwent surgery and postoperative radiation therapy (n = 15), palliative radiation therapy (n = 4), or palliative chemotherapy (n = 2). Nine patients refused to undergo radiation therapy after induction chemotherapy.
RESULTS: The 5-year overall survival rates were as follows: 32% in all patients, 38% in patients who underwent chemotherapy and radiation therapy, and 27% in patients who underwent chemotherapy, surgery, and radiation therapy. The number of days between radiation therapy treatments was highly predictive of overall survival. In the groups with treatments less than 55 days apart, 56-65 days apart, and more than 66 days apart, the 5-year survival rates were 56%, 46%, and 15%, respectively (P = .02).
CONCLUSION: The time between radiation therapy treatments is strongly predictive of survival in patients undergoing sequential chemotherapy and radiation therapy. The use of induction chemotherapy does not negate the need to avoid treatment interruptions during definitive radiation therapy.