Continuous accelerated irradiation (CAIR) of head and neck cancer – treatment technique, toxicity and 2-year results
Abstract
Purpose
Evaluation of preliminary (2-year) treatment results of 7 days a week continuous accelerated irradiation (CAIR) in compare to convectional and concomitant radiotherapy.
Methods
One hundred and twenty eight patients with squamous cell carcinoma of oral cavity, oroand hypopharynx and supraglottic larynx in stage T2-4 NO-1 MO were randomized between 3 groups: A (study-CAIR) – 51 pts, B (control-2) – 28 pts and treated by radiation therapy alone in 1994–96. In majority (81%) there were the patients in advanced clinical stage (T3+T4). Patient and tumour characteristic, radiation technique and volumes, total and fraction doses were exactly the same in 3 groups of patients. Only the overall treatment time was shorter by about 2 weeks in CAIR group comparing to control-1 because of the lack of weekend breaks. The overall treatment time in CAIR and control-2 group was exactly the same because in control-2 group the “CAIR weekend fractions” were given through the Tuesday and Fridays as a concomitant boost.
Results
One hundred twenty five patients (98%) completed the whole designed radiotherapy. Generally, 2-year local tumour control rate (LTCR) in CAIR arm was 87% and in control-1 and control-2 arms respectively 40% and 67% (p<0.0001 log rank). In aspect of tumour localization and stage the LTCR was significantly higher in CAIR arm than in controls and was respectively as follows:
75% vs 10% and 33% in oral cavity,
86% vs 36% and 70% in oropharynx,
88% vs 50% and 80% in hypopharynx and supraglottis;
100% vs 64% and 78% forT2,
94% vs 39% and 67% for T3,
66% vs 26% and 56% for T4.
There were 14% of grade III and IV radiation morbidity in CAIR arm and 4% and 10% in control-1 arms respectively.
Conclusion
The hight effectivness of CAIR fractionation reflects the net effect of not only the simple shortening the overall treatment time by 2 weeks but also the exclusion treatment weekend breaks.