Abstract
BackgroundRadiation pneumonitis (RP) is a major pulmonary adverse event of chest radiotherapy. The PACIFIC trial that identified durvalumab as an effective subsequent‐line therapy after concurrent chemoradiotherapy (CCRT) found that patients with grade 2 or higher RP may have to be excluded from treatment under certain criteria. The purpose of this study was to investigate the relationship between grade ≥2 RP and the parameters of dose‐volume histograms after CCRT with cisplatin/docetaxel for stage III non‐small cell lung cancer and conduct a subset analysis of severe RP that can lead to the permanent discontinuation of treatment per the PACIFIC trial criteria to help determine treatment strategy.MethodsWe calculated the percentage of the lung volume received at least 5 Gy (V5) and 20 Gy (V20), the mean lung dose (MLD), and the lung volume spared from a 5 Gy dose (VS5) to the total lung volume. Factors affecting the incidence of grade ≥2 RP were identified; severe RP was defined as grade ≥3 as well as grade 2 RP that required ≥10 mg prednisolone for at least 12 weeks.ResultsThis study included 45 patients. On univariate analysis, all parameters and total lung volume were found to be significant predictors of grade ≥2 RP (P = .001, .003, .03, .004, and .02, respectively). On multivariate analysis, V20 was a significant predictive factor of grade ≥2 RP (P = .007). Severe RP developed in 6 of 37 patients (16.2%) whose V20 values were 35% or lower. On univariate analysis, only V20 was a significant predictor of severe RP in these patients (P = .01).ConclusionsThe best approach to reduce the rate of grade ≥2 RP is to maintain the V5, V20, MLD, and VS5 as low as possible during radiotherapy planning in patients receiving definitive CCRT with cisplatin/docetaxel.
Highlights
Radiation pneumonitis (RP) is a major pulmonary adverse event of chest radiotherapy
Radiation pneumonitis (RP) is a major pulmonary adverse event that can arise from chest radiotherapy; the incidences of grade ≥3 RP ranged between 1.8% and 10.0% in previous prospective studies, while grade 5 RP rates ranged between 0% and 5.6%
Tsujino et al found that the lung volume spared from a 5 Gy dose (VS5)[12] was predictive of RP
Summary
Concurrent chemoradiotherapy (CCRT) is considered one of the standard treatments for medically inoperable stage III nonsmall cell lung cancer (NSCLC).[1,2,3,4] The standard chemotherapy that is administered simultaneously with radiotherapy is a platinum/taxane combination. Tsujino et al found that the lung volume spared from a 5 Gy dose (VS5)[12] was predictive of RP Another multicenter investigation revealed that the odds ratio of symptomatic RP in patients who received CCRT with carboplatin/paclitaxel was as high as 3.33 when compared with other chemotherapy regimens.[11] RP significantly occurred more frequently in patients undergoing CCRT with cisplatin/ docetaxel than in those receiving concurrent cisplatin/vinorelbine.[8] the concurrent administration of taxanes with radiotherapy is considered a risk factor for RP, no study (to our knowledge) has investigated the correlation between RP and DVH parameters in patients with lung cancer that received CCRT with a single regimen of cisplatin/docetaxel. We determined the rates of severe RP that would render patients permanently ineligible for continued durvalumab treatment under the criteria of the PACIFIC trial, and identified DVH-related risk factors in patients with V20 values
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
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 call
