Dose-volume parameters of MRI-defined active bone marrow spared predict hematologic toxicity in pelvic malignancies patients undergoing radiotherapy: a cohort study

Abstract

Abstract Background The objective of this investigation is to evaluate the superiority of dose-volume parameters relying on magnetic resonance imaging (MRI)-defined active bone marrow (ABM) over those based on total bone marrow (TBM)contoured via CT in the prediction of hematologic toxicity (HT) occurrence among patients with pelvic malignancies undergoing radiotherapy. Methods and materials The clinical data of 116 patients with pelvic malignancies treated with pelvic radiotherapy were analyzed retrospectively. The statistical significance between TBM and ABM dose-volume measures was assessed through the utilization of either Student's t-test or Wilcoxon signed rank test. Furthermore, logistic and linear regression models were employed to analyze the correlation between dose-volume parameters and HT occurrence in pelvic ABM and TBM. Receiver operating characteristic (ROC) curves were used to compare predictors of grade 2 or higher HT (HT2+). Results There were significant differences in dosimetric parameters between ABM and TBM. Logistic regression analysis showed that ABM V5, ABM V10, ABM V15, ABM V20, and TBM V5 were significantly associated with the occurrence of HT2+ in pelvic malignancies. Linear regression analysis showed that ABM V5, ABM V10, and ABM V15 were significantly associated with white blood cell (WBC), absolute neutrophil count (ANC), and hemoglobin (Hb) nadir. ABM V5, ABM V10, ABM V15 and ABM V30 were predictive of HT2+. Conclusion More accurate prediction of HT in patients receiving pelvic radiotherapy can be achieved by relying on dose-volume parameters of MRI-based ABM. Further prospective studies are needed to confirm this.