A clinical trial for advanced cervico-vaginal pelvic carcinomas using californium CF-252 fast neutron therapy: Report of early responses

This report summarizes clinical experiences with Californium (Cf) 252 for the radiotherapy of advanced cervicovaginal carcinomas at the University of Kentucky Medical Center from November 1976 to April 1979. Fifty-nine patients were treated with Cf-252 during this period. After pilot studies, a treatment schedule was developed which appeared to offer improved local control and clearance of these tumors in ∼90% of treated patients. However, a longer follow-up period is essential to determine whether local tumor control is sustained or whether local tumor recurrence remains as great a problem as for patients who receive conventional radio-nuclide therapy. Ultimate long term survival and outcome will depend upon the frequency of control of local-regional disease and the frequency of appearance of more disseminated and metastatic disease. Cf-252 neutron brachytherapy was combined with 4500-5500 rad of Cobalt 60 or linear accelerator external beam fractionated radiotherapy for 4-6 weeks. Neutron treated patients whose disease was in appropriate clinical stages were also treated with combined radiotherapy-surgery without problems. Stage dependent regression was noted; low stage tumors responded distinctly better and more rapidly than higher stage tumors. All histological patterns responded, and no unusual severe or unanticipated early side effects or toxic tissue reactions were observed.