Preoperative vs postoperative radiotherapy in the management of rectal cancer: A systematic review

Purpose. The objective of this study is to review randomized clinical trials systematically that compare the outcomes of preoperative and postoperative radiotherapy in the management of rectal cancer regarding locoregional recurrance, disease free survival and overall survival.Methods. The relevant randomized clinical trials are searched via online databases such as Pubmed, Ebsco, and Proquest. RCTs publised in English between 2000 until 2020 are selected and reviewed systematically.Result. Locoregional recurrence at 5 years was statistically lower in preoperative radiotherapy group than in postoperative radiotherapy group based on two studies. Disease free survival at 5-years was statistically higher in preoprative radiotherapy group than the postoperative one based on two studies. Overall survival at 5 years was not statistically significant between two groups for each study.Conclusion. Preoperative radiotherapy is superior to postoperative radiotherapy for controlling locoregional recurrence and disease free survival, but both are equal in overall survival.

Correlation of Radiation Dose and PSA Blood Level in the Radiotherapy of Prostate Cancer: A retrospective case series

Background: The objective of this study was to analyze the correlation of radiation dose and Prostate-Specific Antigen (PSA) blood level following radiation therapy in prostate cancer.Methods: The study population was serial of 13 patients with histologically proven T1b-T4, any N, M0 prostate adenocarcinoma, having any Gleason score with any PSA before and after complete EBRT (external beam radiotherapy), from January 2009 to December 2010 and evaluated for PSA decrease post-EBRT.Results: Out of 13 patients, one patient received 62 Gy, one patient received 72 Gy, and 11 patients received 80 Gy. PSA blood level was decreased (median 5.4, 9.43 and 25.27, respectively) in all patients.Conclusion: This case series results were consistent with the results of previous studies that a higher radiation dose will have a higher PSA decrease with a tolerable side effect.