Background: Advances in radiation technology have transformed treatment options for patients with localized prostate cancer. The evolution of three-dimensional conformal radiation therapy and intensity-modulated radiation therapy (IMRT) have allowed physicians to spare surrounding normal organs and reduce adverse effects. The introduction of proton beam technology and its physical advantage of depositing its energy in tissue at the end-of-range maximum may potentially spare critical organs such as the bladder and rectum in prostate cancer patients. Data thus far are limited to large, observational studies that have not yet demonstrated a definite benefit of protons over conventional treatment with IMRT. The cost of proton beam treatment adds to the controversy within the field.
Methods: We performed an extensive literature review for all proton treatment-related prostate cancer studies. We discuss the history of proton beam technology, as well as its role in the treatment of prostate cancer, associated controversies, novel technology trends, a discussion of cost-effectiveness, and an overview of the ongoing modern large prospective studies that aim to resolve the debate between protons and photons for prostate cancer.
Results: Present data have demonstrated that proton beam therapy is safe and effective compared with the standard treatment options for prostate cancer. While dosimetric studies suggest lower whole-body radiation dose and a theoretically higher relative biological effectiveness in prostate cancer compared with photons, no studies have demonstrated a clear benefit with protons.
Conclusions: Evolving trends in proton treatment delivery and proton center business models are helping to reduce costs. Introduction of existing technology into proton delivery allows further control of organ motion and addressing organs-at-risk. Finally, the much-awaited contemporary studies comparing photon with proton-based treatments, with primary endpoints of patient-reported quality-of-life, will help us understand the differences between proton and photon-based treatments for prostate cancer in the modern era.
Comparative treatment planning on localized prostate carcinoma conformal photon- versus proton-based radiotherapy.Strahlenther Onkol. 2005 Jul;181(7):448-55. doi: 10.1007/s00066-005-1317-7. Strahlenther Onkol. 2005. PMID: 15995838
What is the best way to radiate the prostate in 2016?Urol Oncol. 2017 Feb;35(2):59-68. doi: 10.1016/j.urolonc.2016.06.002. Epub 2016 Jul 6. Urol Oncol. 2017. PMID: 27395453 Review.
Proton therapy in the clinic.Front Radiat Ther Oncol. 2011;43:465-485. doi: 10.1159/000322511. Epub 2011 May 20. Front Radiat Ther Oncol. 2011. PMID: 21625169 Review.
Dosimetric advantages of IMPT over IMRT for laser-accelerated proton beams.Phys Med Biol. 2008 Dec 21;53(24):7151-66. doi: 10.1088/0031-9155/53/24/010. Epub 2008 Nov 26. Phys Med Biol. 2008. PMID: 19033641
Cost of New Technologies in Prostate Cancer Treatment: Systematic Review of Costs and Cost Effectiveness of Robotic-assisted Laparoscopic Prostatectomy, Intensity-modulated Radiotherapy, and Proton Beam Therapy.Eur Urol. 2017 Nov;72(5):712-735. doi: 10.1016/j.eururo.2017.03.028. Epub 2017 Mar 31. Eur Urol. 2017. PMID: 28366513 Free PMC article. Review.