Effects of Whole Pelvic Radiotherapy on the Distribution of Lymphocyte Subpopulations in Prostate Cancer Patients

Introduction: In the current study, we have investigated the effects of the different modalities of treatment (volume of radiotherapy [RT], previous surgery) as well as the Gleason score of prostate cancer (PC) on the lymphocyte composition of PC patients undergoing RT. Methods: This is a monoinstitutional study that prospectively included PC patients that underwent RT from January 2016 until December 2017. To compare the different evaluations, the Wilcoxon signed-rank test was used among 2 times (Timepoint 0 to Timepoint 1). Percentage variation was calculated for all the lymphocyte subpopulation and was correlated with clinical parameters (previous surgery, Gleason score, and pelvic irradiation) with the chi(2) test. The statistical analysis was repeated also on the stratified dataset according to the above parameters (previous surgery, Gleason score, and whole pelvic radiotherapy [WPRT]). Results: One hundred and eleven patients were included in the present analysis. All the lymphocyte subpopulations resulted significantly lower after RT. The modifications of several lymphocyte subpopulations correlated with previous surgery, Gleason score, and WPRT, although stratified analysis demonstrated that WPRT showed the greatest correlation. Conclusion: Our results could be used to design a prospective trial in order to study the use of WPRT on the lymphocyte subpopulations.