A feasibility study of 252Cf neutron brachytherapy, cisplatin + 5-FU chemo-adjuvant and accelerated hyperfractionated radiotherapy for advanced cervical cancer.

Purpose: To evaluate the feasibility and toxicity of 252Cf neutron brachytherapy combined with hyperaccelerated chemoradiotherapy for Stage III and IV cervical cancers.
Methods and Materials: Eleven patients with advanced Stage IIIB-IVA cervical cancers were treated with 252Cf neutron brachytherapy in an up-front schedule followed by cisplatin (CDDP; 50 mg/m2) chemotherapy and hyperfractionated accelerated (1.2 Gy bid) radiotherapy given concurrently with intravenous infusion of 5-Fluorouracil (5-FU) (1000 mg/m2/day x 4 days) in weeks 1 and 4 with conventional radiation (weeks 2, 3, 5, and 6). Total dose at a paracervical point A isodose surface was 80-85 Gy-eq by external and intracavitary therapy and 60 Gy at the pelvic sidewalls.
Results: Patients tolerated the protocol well. There was 91% compliance with the chemotherapy and full compliance with the 252Cf brachytherapy and the external beam radiotherapy. There were no problems with acute chemo or radiation toxicity. One patient developed a rectovaginal fistula (Grade 3-4 RTOG criteria) but no other patients developed significant late cystitis, proctitis or enteritis. There was complete response (CR) observed in all cases. With mean follow-up to 26 months, local control has been achieved with 90% actuarial 3-year survival with no evidence of disease (NED).
Conclusion: 252Cf neutrons can be combined with cisplatin and 5-FU infusion chemotherapy plus hyperaccelerated chemoradiotherapy without unusual side effects or toxicity and with a high local response and tumor control rate. Further study of 252Cf neutron-chemoradiotherapy for advanced and bulky cervical cancer are indicated. We found chemotherapy was more effective with the improved local tumor control.