X Tong*, FS Luo, GR Yang, DP Wang, X Song, Y Chen, S Wu, N Zhang, QQ Xu, T Zhang, and J Li
3rd Affiliated Hospital of Qiqihar Medical University, Qiqihar, China
*Corresponding author: Xu Tong, MD, 3rd Affiliated Hospital of Qiqihar Medical University, Qiqihar, China. Email: [email protected]
Received Date: December 06, 2021
Published Date: December 21, 2020
Copyrights: Tong X. © (2021).
Citation: Tong X. (2021). A Clinical Study on Pulsed Low Dose Rate Radiation Therapy for Recurrent Cancers. Mathews J Cancer Sci. 6(1):28.
A consensus standard of care has not been established for treating recurrent cancer patients who have previously undergone radiation therapy (RT). Several in vitro and in vivo studies have shown that pulsed low-dose-rate RT (PLDR) has the potential to reduce normal tissue toxicities while still providing significant tumor control for recurrent cancers. This work investigated PLDR re-irradiation for patients with recurrent cancers in head and neck (H&N), lung and pelvis. Thirteen patients with recurrent cancer were treated with the PLDR technique between 2012 and 2014. The re-irradiation sites included neck nodes, lung, chest wall, thyroid, pelvic nodes, pelvic nodes, uterus, cervix and vagina, supraclavicular nodes, and spine. The previous dose was ≥ 50Gy for all patients, while the re-irradiation dose was 16-60Gy. The interval between prior RT treatment and re-irradiation was 13 – 336 months, and the follow-up time was up to 27 months. The PLDR treatments were effective (CR: 3 patients, PR: 10 patients). The acute and late toxicities were all acceptable (generally grade 2 or under). Our preliminary clinical results demonstrated the effectiveness of the PLDR technique for the palliative treatment of recurrent H&N, lung, rectal and gynecologic cancers. Further clinical trials are warranted to quantify the efficacy of PLDR for recurrent cancers and other radiation resistant cancers and/or large treatment volumes involving critical structures.
Keywords: Pulsed low dose-rate RT (PLDR), re-irradiation, recurrent cancer, dose rate effect, tumor control, normal tissue toxicities