Fast neutron therapy in Tomsk: 40-year experience in cancer treatmnet

The purpose of the study was to evaluate the efficacy of neutron therapy (NT) for salivary gland cancer and recurrent breast cancer. Material and Methods. The study included 130 patients with salivary gland cancer and 125 patients with recurrent breast cancer. Fast neutron therapy using U-120 cyclotron was given to the patients of the study group. Patients of the control group received standard radiotherapy (external beam radiotherapy). Results. Among patients with salivary gland cancer, a recurrence rate was significantly lower in patients who received a postoperative course of NT compared to patients of the control group (21.1 vs 45 %, p<0.05). The five-year overall survival rates were 73.8 ± 9.5 % and 43.2 ± 9.4 % in the study group and the control group, respectively (p<0.05). The five-year disease-free survival rates were 65.6 ± 7.5 % and 34.8 ± 9.1 % in the study and control groups, respectively (p<0.05). In patients with recurrent breast cancer, a significant increase in the frequency of complete regression in the study group compared to the control group was observed (91.8 vs 51.3 %, p<0.05). Ten-year survival rates in patients with no evidence of re-recurrence were 77.4 ± 8.7 % and 44.7 ± 8.8 % in the study group and the control group, respectively (p<0.05). Conclusion. The study demonstrated efficacy of fast neutron therapy in patients with salivary gland cancer and recurrent breast cancer. Neutron therapy did not result in serious complications, improved survival of the patients and decreased the recurrence rate compared with standard radiotherapy.