Importance of Chemotherapy and Radiation Dose After Microscopically Incomplete Resection of Stage III/IV Head and Neck Cancer.

Objective: To investigate the importance of chemotherapy and radiation dose after R1 resection of squamous cell carcinoma of the head-and-neck (SCCHN).

Methods: One hundred and twenty-two patients receiving radiotherapy alone or with concurrent chemotherapy [cisplatin or cisplatin/5-fluorouracil (5-FU)] were retrospectively analyzed.

Results: On multivariate analysis, chemotherapy was significantly associated with improved locoregional control (p=0.048). Three-year locoregional control rates were 61% for those treated without chemotherapy, 83% for those treated with cisplatin and 77% for those treated with cisplatin/5-FU. Radiation doses of 66 and 70 Gy were non-significantly superior to 60-64 Gy (p=0.18). On multivariate analysis, chemotherapy showed a trend for improving survival (p=0.055). Three-year OS rates were 51% for those without chemotherapy, 65% for those treated with cisplatin and 57% for those treated with cisplatin/5-FU. Radiation doses of 66 Gy (3-year survival=61%) and 70 Gy (70%) were superior to 60-64 Gy (25%) (p=0.021).

Conclusions: Concurrent chemotherapy and a radiation dose of 66 Gy resulted in better outcomes. Cisplatin and cisplatin/5-FU were similarly effective. Radiation doses >66 Gy appear not to be necessary.