Tumor regression and histologic clearance after neutron brachytherapy for bulky localized cervical carcinoma.

The response of bulky, advanced Stage 1B and early Stage II carcinoma of the cervix to neutron brachytherapy (NT and radiotherapy) was studied using combined NT radiation and extrafascial hysterectomy with histologic evaluation. Scheduling of neutron therapy relative to external beam photon therapy, tumor volume, tumor stage, tumor histology, and clinical tumor clearance were assessed in these studied. NT was easily combined with surgery in this study. Low stage tumors, small tumor volume and "early" neutron implants (scheduled within +/- one week of the start of fractionated radiation) showed more frequent histologic clearance of tumor. Long-term tumor control has been achieved and failures developed distance metastases without pelvic or local recurrence. This experience indicates that NT was effective for tumor clearance and control and represents and promising new modality for localized, advanced tumor therapy.