Abstract
Results: Twenty-eight patients were evaluable, all received 50.4 Gy with concurrent chemotherapy. Pneumonitis CTCAEv4 toxicity scores were: 1 grade 3, 3 grade 2, 7 grade 1, and 17 grade 0. Dosimetric factors were not predictive of symptoms. Exhaled NO measured before, at completion, and at restaging were 17.3 (SD 8.5; range 5.5 - 36.7), 16.0 (14.2; 5.8 - 67.7), 14.7 (6.2; 5.5 - 28.0) parts perbillion(ppb)respectively.Eachmeasurementwasmadeintriplicatewithanaveragestandarderrorof0.8ppb.Theratioof exhaledNOattheendofradiotherapyversuspre-treatmentwas3.4(1.7-6.7)forthesymptomaticand0.8(0.3-1.3)fortheasymptomatic (p value = 0.0017). Elevation in exhaled NO preceded peak symptoms by 33 (21 - 50) days. The time to peak symptoms wasfoundtobeinverselyrelatedtotheexhaled NOelevation.TheexhaledNOratio (endversusbefore)wastestedas apredictorof symptomsusingthedatafromthistrialandthek-nearestneighborclassifierschemedescribed.TheNOratiopredictedsymptomatic patients with an average error rate of 8%. Conclusions: Elevation in the exhaled NO at the end of radiotherapy was found to predict for radiation pneumonitis symptoms. Time to peak symptoms was inversely related to the elevation in exhaled NO, higher elevation was associated with a shorter time. Author Disclosure: T. Guerrero, None; J. Martinez, None; M.R. McCurdy, None; M.J. Wolski, None; M.F. McAleer, None.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: International Journal of Radiation Oncology*Biology*Physics
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
