Proton Therapy for Vaginal Reirradiation

Abstract

Primary or recurrent gynecologic cancers in operable patients with a history of prior pelvic radiation are typically treated with surgery based on the risk of late toxicities historically associated with reirradiation. A number of studies have demonstrated that, compared with conventional radiation therapy (RT) using photons, proton therapy (PT) offers dosimetric advantages for patients with gynecologic cancers by reducing radiation dose to healthy tissues. Thereby, we expect that, in appropriately selected cases, PT may reduce long-term treatment-related morbidities without compromising treatment efficacy. Herein, we describe the treatment planning, technique, and long-term follow-up of a patient who was treated with PT for a primary vaginal carcinoma nearly 30 years after a prior course of pelvic RT. Using this case, we illustrate the utility and advantages of PT in the treatment of cancers that occur at less favorable sites, adjacent to normal structures with low radiation tolerance, or in paients with a history of prior irradiation. Additionally, we provide a brief discussion and review of literature of prior case series of pelvic reirradiation, illustrating the value of identifying treatment approaches that can reduce treatment-related morbidities, particularly late treatment toxicities.

Reirradiation for Locoregional Recurrent Breast Cancer

“…Particularly, high rates of disease control were seen among curative intent patients undergoing complete surgical excision followed Proton therapy for breast cancer offers enhanced ability to spare non-target tissue, including the heart and lungs [24,[28][29][30][31][32][33], which is of particular importance and interest for re-irradiation. Reirradiation with PBT has been reported in multiple disease sites, including in CNS, head and neck, gynecological, gastrointestinal, and lung tumors [34][35][36][37][38][39][40][41]. There are limited data in the setting of breast reirradiation.…”

Proton beam therapy reirradiation for breast cancer: Multi‐institutional prospective PCG registry analysis

“…Proton beam therapy for reRT has been investigated at other disease sites including head and neck, 38,39 central nervous system, 40,41 lung, 42,43 gynecological, 44 and gastrointestinal malignancies. [45][46][47] A recent systematic review found that reRT with PBT is safe and effective.…”

Establishment of a new three-dimensional dose evaluation method considering variable relative biological effectiveness and dose fractionation in proton therapy combined with high-dose-rate brachytherapy

“…There are many reports of proton therapy combined with HDR brachytherapy applied to gynecological disorders such as cervical cancer. [567] Proton beam is an excellent external irradiation method for gynecological disorders,[737] and the possibility of replacing the X-rays commonly used in HDR brachytherapy combination has been reported. [7] Therefore, it is essential to take into account the RBE and dose fractionation.…”

“…There is proton therapy combined with high-dose-rate (HDR) brachytherapy, which uses proton beams and gamma rays. [567] To safely conduct such combination using different kinds of radiation, accurate dose evaluation is necessary. This is because the biological effects of each radiation are completely different, and radiation damage may occur.…”