SCIENTIFIC AND INFORMATION-ANALYTICAL MAGAZINE

ISSN 1024-6177 (Print), ISSN 2618-9615 (Online)

Medical Radiology and Radiation Safety. 2017. Vol. 62.  No. 1. P. 65-69

DOI: 10.12737/25063

Evaluation of Therapeutic Gain Factor in Neutron Therapy Based on the Linear Quadratic Model

V.A. Lisin

Tomsk Cancer Research Institute, Tomsk, Russia, e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

V.A. Lisin - professor, Department of applied physics, Doctor of Engineering Science

Abstract

Purpose: To study the dependencies of therapeutic gain factor (TGF) on dose of cyclotron-produced fast neutron beams using the linear-quadratic model (LQM) parameters characterizing radiation response in tumor and normal tissues.

Material and methods: The TGF in neutron therapy was calculated as the ratio of the relative biological effectiveness of neutrons for tumor (RBE tumor) to relative biological effectiveness for normal tissue (RBE normal tissue). The LQM was used to calculate the dependencies of neutron RBE on the dose and therapeutic gain factor. We considered two cases: 1) neutron therapy for 3 types of tumors with different radiation response, where the same normal tissue was critical; 2) neutron therapy for the same tumor, when 3 types of normal tissues were taken as critical.

Results: Based on calculations and analysis of published data, the dependencies of neutron RBE on dose for selected types of tumors and normal tissues were obtained. The following variants were considered: 1) RBE tumor > RBE normal tissue; 2) RBE tumor < RBE normal tissue, in both two variants, the dependencies in the therapeutic dose rate were convergent; 3) the dependencies of RBE tumor and RBE normal tissue on dose are crossed. The dependencies of TGF for neutron therapy on single boost doses and quantitative ratios between the LQM parameters characterizing radiation response of tumor and normal tissues were found. A multivariate ratio between the dependencies on dose of RBE tumor and RBE normal tissue was the cause of variety in the dependencies of TGF on dose. In the first case, the TGF increased with increasing (α/β)γ ratio and decreasing single dose, and the maximum value of TGF was equal to ~ 1.4. In the second case, TGF was < 1, i.e. the effectiveness of neutron therapy was lower than the effectiveness of gamma irradiation, but it was increased with higher single dose and lower radiosensitivity of normal tissue. In the third case, the dose at the intersection point (Di) was the boundary, and TGF was > 1 to the left of the boundary, and TPV was <1 to the right of the boundary, provided that D <Di, RBEtumor > OBEnormal tissue.

Conclusion: The obtained results with known parameters of the LQM for tumor and normal tissues allowed us to make an appropriate choice between neutron and gamma- ray therapy in order to increase the effectiveness of treatment for cancer patients. It was shown that in the case of neutron therapy, the analysis of dependencies of TGF on dose allowed the optimal dose fractionation regimen to be selected.

Key words: neutron therapy, linear-quadratic model, therapeutic gain factor

REFERENCES

  1. Stone R. Neutron therapy and specific ionization. Janewry Memorial Lecturell. Amer. J. Roentgenol. 1948. Vol. 59. P. 771-778.
  2. Catterall M., Bewley D.K. Fast Neutrons in the Treatment of Cancer. London, Academic Press, New York. Grune and Stratto. 1979. 394 p.
  3. Zyrjanov B.N., Musabaeva L.I., Letov V.N., Lisin V.A. Distan­cionnaja nejtronnaja terapija. Tomsk: Publ. TGU. 1991. 300 p. (In Russ.).
  4. Lisin V.A. Dozimetricheskoe komp’juternoe planirovanie terapii zlokachestvennyh opuholej puchkom bystryh nejtronov ciklotrona U-120. Med. radiol. i radiac. bezopasnost’. 1991. No. 1. P. 26-28. (In Russ.).
  5. Gulidov I.A., Mardynskij Ju.S., Vtjurin B.M. et al. Bystrye nejtrony reaktora v sochetannoj gamma-nejtronnoj terapii bol’nyh rakom organov polosti rta i rotoglotki. Ross. onkol. zhurnal. 2000. Vol. No. 4-7. (In Russ.).
  6. Gulidov I.A., Mardynskij Ju. S., Cyb A.F., Sysoev A.S. Nejtrony jadernyh reaktorov v lechenii zlokachestvennyh novoobrazovanij. Obninsk: Publ.: MRNC RAMN. 2001. 132 p. (In Russ.).
  7. Vazhenin A.V., Rykovanov G.N. Ural’skij centr nejtronnoj terapii: istorija sozdanija, metodologija, rezul’taty rabot. Moscow: Publ. RAMN. 2008. 124 p. (In Russ.).
  8. Musabaeva L.I., Zhogina Zh.A., Slonimskaja E. M., Lisin V.A. Sovremennye metody luchevoj terapii raka molochnoj zhelezy. Tomsk. 2003. 200 p. (In Russ.).
  9. Musabaeva L.I., Lisin V.A. Response of resistant malignant tumors to neutron therapy. Adv. Mater. Res. 2015. Vol. 1084. P. 467-470.
  10. Wagner F.M., Specht H., Loeper-Kabasakal B., Breitkreutz H. Sovremennoe sostoyanie terapii bystrymi nejtronami. Sib. onkol. zhurnal. 2015. No. 6. P. 5-11. (In Russ.).
  11. Kandakova E.YU. Kliniko-ehksperimental’noe obosnovanie povysheniya ehffektivnosti sochetannoj fotonno-nejtronnoj terapii opuholej golovy i shei. Diss. dokt. Moscow. 2015. 197 p. (In Russ.).
  12. Mel’nikov A.A., Vasil’ev S.A., Smol’nikova E.V. et al. Dinamika hromosomnyh aberracij i mikroyader v limfocitah bol’nyh zlokachestvennymi novoobrazovaniyami pri nejtronnoj terapii. Sib. onkol. zhurnal. 2012. No. 4. P. 52-56. (In Russ.).
  13. Makarova G.V. Radiobiologicheskie predposylki primeneniya bystryh nejtronov v luchevoj terapii zlokachestvennyh opuholej. V kn: «Bystrye nejtrony v luchevoj terapii zlokachestvennyh opuholej». In: Rudermana A.I., Franka I.M. (eds.). Moscow. 1976. 172 p. (In Russ.).
  14. Dale R.G., Jones B. The assessment of RBE effects using the concept of biologically effective dose. Int. J. Radiat. Oncol. Biol. Phys. 1999. Vol. 43. No. 3. P. 639-645.
  15. Osobennosti mehanizmov dejstvija plotnoionizirujushhih izluchenij. In: Savicha A.V., Mazurika V.K. (eds.) Moscow: Medicina. 1985. 230 p. (In Russ.).
  16. Letov V.N. Radiobiologicheskie issledovanija nejtronov. V kn: Zyrjanov B.N., Musabaeva L.I., Letov V.N., Lisin V.A. Distancionnaja nejtronnaja terapija. Tomsk: Publ. TGU. 1991. P. 48-103. (In Russ.).
  17. Ivanov V.I., Mashkovich V.P., Center Je.M. Mezhdunarodnaja sistema edinic v atomnoj nauke i tehnike. Moscow. Jenergoizdat. 1981. 196 p. (In Russ.).
  18. Lisin V.A. Ocenka parametrov linejno-kvadratichnoj modeli v nejtronnoj terapii. Med. fizika. 2010. No. 4. P. 5-12. (In Russ.).
  19. Carlsson J., Stenerlow B., Russell K. et al. Cell type dependent effectiveness of tumor cell inactivation by radiation with increased ionization density. Anticancer Res. 1995. Vol. 15. P. 273-282.
  20. Hornsey S., Field S. The RBE of cyclotron neutrons for effect on normal tissues. Eur. J. Cancer. 1974. Vol. 10. P. 231-234.
  21. Pavlov A.S., Fadeeva M.A., Karjakina N.F. et al. Linejno-kvadra­tichnaja model’ v raschetah izojeffektivnyh doz, v ocenke protivo­opuholevogo jeffekta i luchevyh oslozhnenij pri luchevoj terapii zlokachestvennyh opuholej. Posobie dlja vrachej. Moscow. 2005. 67 p. (In Russ.).

For citation: Lisin VA. Evaluation of Therapeutic Gain Factor in Neutron Therapy Based on the Linear Quadratic Model. Medical Radiology and Radiation Safety. 2017;62(1):65-9. Russian. DOI: 10.12737/25063

PDF (RUS) Full-text article (in Russian)

© Журнал "Медицинская радиология и радиационная безопасность" 2020г.

Яндекс.Метрика

Наверх