Relationship Of Dosimetric Parameters Of Irradiated Bone Marrow And Hematologic Toxicities In Locally Advanced Adenocarcinoma Of The Esophagogastric Junction Patients Treated With Preoperative Chemoradiotherapy

Objective:To identify the relationships between dosimetric parameters of the irradiated bone marrow(BM)and hematologic toxicities in locally advanced adenocarcinoma of the esophagogastric junction(AEG)patients treated with preoperative chemoradiotherapy(CRT).Method: We retrospectively analyzed 60 patients of AEG treated with concurrent oxaliplatin-capecitabine and radiotherapy.Irradiated BM(vertebrae,ribs,sternum,and total irradiated BM(BM-T))were delineated for each patient.Dose-volume histogram(DVH)parameters for BM were calculated and related with the hematologic toxicity(HT).Results: For 60 patients with AEG,55%(33/60)developed grade ≥2 HT including neutropenia developed in 11.67%(n=7),anemia in 1.67%(n=1),and thrombocytopenia in 33.33%(n=20)of patients.Univariate logistic regression analysis showed that increasing ribs V30(P=0.034),ribs V35(P=0.008),ribs V40(P=0.018),ribs V45(P=0.016),and BM-T V25(P=0.026)were associated with increased risk of grade ≥2 leukopenia,and increasing sternum V25(P=0.041),sternum V30(P=0.019),sternum V35(P=0.034),and BM-T V25(P=0.035)were associated with increased risk of grade ≥2 HT.Multivariate logistic regression analysis demonstrated that ribs V35 and BM-T V25 were associated with increased risk of grade ≥2leukopenia,and BM-T V25 were associated with increased risk of grade ≥2HT.Cut-off values to avoid grade ≥2 leukopenia were ribs V35≤7.86%,and whole BMV25≤ 49.67%.Cutoff values to avoid grade ≥2 HT was whole BMV25≤ 41.21%.Conclusion: Reducing the irradiation of bone marrow may decrease thehematologic toxicity of grade 2 and higher in the patients during chemoradiotherapy.