Treatment of cervical carcinoma with ionizing irradiation using moving fields

This study was designed to assess the effectiveness and risk of complications from radiotherapy delivered by the moving field technique as opposed to the more commonly used fixed field technique. Between 1975 and 1985, 131 patients were treated for cervical cancer with a combination of teletherapy and brachytherapy. For teletherapy, 4-MeV photons were used and delivered by moving field technique (120 degrees to 160 degrees arcs, or a 360 degrees rotation). Most patients received one intracavitary radium implant using Fletcher-Suit applicators and the Manchester technique. Twenty-two percent of the patients had stage I disease, 37% stage II, 25% stage III, 13% stage IV, and 2% were unstaged. The cumulative 5-year survival for all patients was 57%. The survival by stage was: stage I, 82%, stage II, 62%, stage III, 53%, and stage IV, 6%. Chronic complications developed in 10 (7.6%) patients. The survival and complication rate of patients treated for cervical cancer with radiation using moving fields compares favorably with that of patients treated with the conventional parallel opposed (AP-PA) fields or the four-field box technique. Further studies are necessary to definitively determine if the moving field technique offers advantages over other techniques.