title: Thoracic Vertebral Body Irradiation Contributes to Acute Hematologic Toxicity During Chemoradiation Therapy for Non-Small Cell Lung Cancer.
abstract: OBJECTIVE
  To determine the relationships between radiation doses to the thoracic bone marrow and declines in blood cell counts in non-small cell lung cancer (NSCLC) patients treated with chemoradiation therapy (CRT).
  
  
  METHODS
  We included 52 patients with NSCLC treated with definitive concurrent carboplatin-paclitaxel and RT. Dose-volume histogram (DVH) parameters for the thoracic vertebrae (TV), sternum, scapulae, clavicles, and ribs were assessed for associations with changes in blood counts during the course of CRT. Linear and logistic regression analyses were performed to identify associations between hematologic nadirs and DVH parameters. A DVH parameter of Vx was the percentage of the total organ volume exceeding x radiation dose.
  
  
  RESULTS
  Grade ≥ 3 hematologic toxicity including neutropenia developed in 21% (n=11), leukopenia in 42% (n=22), anemia in 6% (n=3), and throbocytopenia in 2% (n=1) of patients. Greater RT dose to the TV was associated with higher risk of grade ≥ 3 leukopenia across multiple DVH parameters, including TV V20 (TVV) (odds ratio [OR] 1.06; P=.025), TVV30 (OR 1.07; P=.013), and mean vertebral dose (MVD) (OR 1.13; P=.026). On multiple regression analysis, TVV30 (β = -0.004; P=.018) and TVV20 (β = -0.003; P=.048) were associated with white blood cell nadir. Additional bone marrow sites (scapulae, clavicles, and ribs) did not affect hematologic toxicity. A 20% chance of grade ≥ 3 leukopenia was associated with a MVD of 13.5 Gy and a TTV30 of 28%. Cutoff values to avoid grade ≥ 3 leukopenia were MVD ≤ 23.9 Gy, TVV20 ≤ 56.0%, and TVV30 ≤ 52.1%.
  
  
  CONCLUSIONS
  Hematologic toxicity is associated with greater RT doses to the TV during CRT for NSCLC. Sparing of the TV using advanced radiation techniques may improve tolerance of CRT and result in improved tolerance of concurrent chemotherapy.
authors.affiliation: Department of Radiation Oncology, Rutgers Cancer Institute of New Jersey, Robert Wood Johnson Medical School, Rutgers University, New Brunswick, New Jersey.
authors.forename: Matthew P
authors.initials: MP
authors.lastname: Deek
authors.affiliation: Department of Radiation Oncology, Rutgers Cancer Institute of New Jersey, Robert Wood Johnson Medical School, Rutgers University, New Brunswick, New Jersey.
authors.forename: Brian
authors.initials: B
authors.lastname: Benenati
authors.affiliation: Department of Biostatistics, School of Public Health, Rutgers University, Piscataway, New Jersey; Biometrics Division, Rutgers Cancer Institute of New Jersey, Robert Wood Johnson Medical School, Rutgers University, New Brunswick, New Jersey.
authors.forename: Sinae
authors.initials: S
authors.lastname: Kim
authors.affiliation: Department of Radiation Oncology, Rutgers Cancer Institute of New Jersey, Robert Wood Johnson Medical School, Rutgers University, New Brunswick, New Jersey.
authors.forename: Ting
authors.initials: T
authors.lastname: Chen
authors.affiliation: Department of Radiation Oncology, Rutgers Cancer Institute of New Jersey, Robert Wood Johnson Medical School, Rutgers University, New Brunswick, New Jersey.
authors.forename: Inaya
authors.initials: I
authors.lastname: Ahmed
authors.affiliation: Department of Radiation Oncology, Rutgers Cancer Institute of New Jersey, Robert Wood Johnson Medical School, Rutgers University, New Brunswick, New Jersey.
authors.forename: Wei
authors.initials: W
authors.lastname: Zou
authors.affiliation: Division of Medical Oncology, Rutgers Cancer Institute of New Jersey, Robert Wood Johnson Medical School, Rutgers University, New Brunswick, New Jersey.
authors.forename: Joseph
authors.initials: J
authors.lastname: Aisner
authors.affiliation: Department of Radiation Oncology, Rutgers Cancer Institute of New Jersey, Robert Wood Johnson Medical School, Rutgers University, New Brunswick, New Jersey. Electronic address: jabbousk@cinj.rutgers.edu.
authors.forename: Salma K
authors.initials: SK
authors.lastname: Jabbour
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000740:Anemia / Q000209:etiology; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D001853:Bone Marrow / Q000528:radiation effects; D001842:Bone and Bones / Q000528:radiation effects; D016190:Carboplatin / Q000008:administration & dosage; D002289:Carcinoma, Non-Small-Cell Lung / Q000628:therapy*; D059248:Chemoradiotherapy / Q000009:adverse effects*; D005260:Female; D006402:Hematologic Diseases / Q000209:etiology*; D006801:Humans; D007970:Leukopenia / Q000209:etiology; D008175:Lung Neoplasms / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D009503:Neutropenia / Q000209:etiology; D017239:Paclitaxel / Q000008:administration & dosage; D011829:Radiation Dosage; D011836:Radiation Tolerance; D012044:Regression Analysis; D013904:Thoracic Vertebrae / Q000528:radiation effects*; D013921:Thrombocytopenia / Q000209:etiology
chemical_list: D016190:Carboplatin; D017239:Paclitaxel