11P - 10-year results of complex treatment with reactor neutrons in locally advanced breast cancer (BC)

Date 07 May 2015
Event IMPAKT 2015
Session Welcome reception and Poster Walk
Topics Breast Cancer, Locally Advanced
Surgery and/or Radiotherapy of Cancer
Presenter Yury Ragulin
Citation Annals of Oncology (2015) 26 (suppl_3): 4-5. 10.1093/annonc/mdv114
Authors Y. Ragulin1, Y. Mardynsky2, I. Gulidov2, G. Aminov1, V. Medvedev1, A. Sysoev2, I. Kotuchov2
  • 1Thoracic Department, Medical Radiological Research Center, 249036 - Obninsk/RU
  • 2Radiology Department, Medical Radiological Research Center, 249036 - Obninsk/RU

Abstract

Body

Treatment of locally advanced BC remains a difficult and unsolved problem. Radiation therapy (RT) with neutrons is seldom used in complex treatment of patients with BC though all obtained experience testifies to good prospects of their application. We present the 10-year results of treatment of 201 patients (pts) with BC who received RT as a component of complex treatment. 95 received the mixed photon-neutron therapy (group A), and 106 — photon therapy only (group B). All patients had stage III disease. The mixed photon-neutron therapy was carried out by two techniques: with the first technique neutron therapy of 0,4Gy 5 times a week to total dose of neutrons of 2Gy, and then photon therapy on 2Gy 5 times a week to an equivalent dose of 60Gy in the beginning was carried out. With the second technique the photon therapy on 2Gy 5 times a week was carried out, a neutron contribution of 3Gy (on 1Gy of neutrons every other day). Thus the dose of photon therapy was 48Gy, and equivalent total dose 60Gy. Group B differed only in that during all course of treatment the patient received only photon therapy on 2Gy 5 times a week to total dose 60Gy. The beam of B-3 of the IPPE BR-10 reactor (Obninsk) with average energy of neutrons near 1МeV at distance from an active zone of the reactor to the patient about 10 m was used as a source of neutrons. The frequency of early and late radiation toxicity and quality of life of pts were similar in the groups. Complete response of a tumor after a mixed photon-neutron therapy was observed in 28,4% and after photon therapy only in 0,9% of pts (P < 0,001). As a result, it was succeeded to operate 39 pts (41,1%) from the group A and only 24 pts (22,6%) from group B. Ten-year overall survival was 32,8% in group A, in group B - 17,1% (P < 0,02). Ten-year disease-free survival was 29,5% in group A, in group B - 7,4% (P < 0,02). Local recurrence is revealed only at 13,5% of pts of the group A, in group B - 44,4% (P < 0,005). In group B local recurrences appeared rather evenly throughout first four years, and in the group A their majority is registered within the second year of follow-up. Our data on the mixed photon-neutron therapy prove possibility of achievement of high efficiency of treatment and satisfactory level of quality of patient's life.

Disclosure: All authors have declared no conflicts of interest.