Moeko Ishijima, Presenter: Nothing to Disclose

Hidetsugu Nakayama, Abstract Co-Author: Nothing to Disclose

Yu Tajima, Abstract Co-Author: Nothing to Disclose

Sachika Nogi, Abstract Co-Author: Nothing to Disclose

Ryuji Mikami, Abstract Co-Author: Nothing to Disclose

Koichi Tokuuye MD, PhD, Abstract Co-Author: Nothing to Disclose

Soichi Akata MD, Abstract Co-Author: Nothing to Disclose

Purpose/Objective(s): Radiation pneumonitis is a major complication, which can cause life-threatening conditions. Little is known about the association between underlying lung diseases and radiation-induced lung injuries. We investigated patients with stage I non-small cell lung cancer (NSCLC) who underwent stereotactic body radiotherapy (SBRT) to clarify it.Materials/Methods: Between February 2010 and May 2012, 23 consecutive patients with stage I NSCLC at the Tokyo Medical University were included. The median age was 79 years (range, 68-90). Sixteen (82.6%) patients had smoking history. Number of T1 and T2 tumors were respective 9 and 14. Twelve tumors were located in the upper lobe, 2 the middle lobe, and 9 the lower lobe. Concerning underlying lung diseases, 12 patients had emphysema, one interstitial pneumonitis, and the remaining 10 normal lung. Emphysema was classified into three groups according to the Goddard’s criteria (severe: 3, intermediate: 6, mild: 3). All 23 tumors were irradiated at 75 Gy in 30 fractions using SBRT. A median V20 value was 9.1% (range, 0.6-16.3). Lung injuries after radiotherapy were assessed according to common terminology criteria for adverse events (CTCAE, ver.4.0) and classified into two groups according to CT findings; radiation pneumonitis was defined when CT finding was confined out of the irradiated volume and radiation fibrosis was defined when CT finding was confined in the irradiated volume. The time to lung injuries on CT was calculated from the completion of radiotherapy. Kaplan-Meier’s methods and log-rank tests were used to compare the incidence of radiation injuries.Results: During median observation period of 375 days, the median time to lung injury development was 150 days. Seventeen patients experienced Grade 1 pulmonary-toxicities according to CTCAE, who were asymptomatic and did not need any medication. Fifteen (65.2%) patients and 2 (8.7%) patients had radiation fibrosis and radiation pneumonitis, respectively, and the remaining 6 (26.1%) patients had no lung injuries. Of the 6 who did not experienced lung injury, three had severe emphysema and 2 had normal lung. Patients who had severe emphysema had less tendency to have lung injuries compared to those who had not (P = 0.03). Lung injuries developed earlier in the lower lobe than that in the upper or the middle lobe (P = 0.02). Smoking history, brinkman index (≥1000 vs. <1000), age (≥75 vs. <75), sex, location (peripheral vs. central), T-factor (T1 vs. T2) and V20 (≥10 vs. <10) were not statistically significant.Conclusions: Patients who had severe emphysema did not suffer from radiation-induced lung injuries after SBRT.

Ishijima, M, Nakayama, H, Tajima, Y, Nogi, S, Mikami, R, Tokuuye, K, Akata, S, Lung Injuries after Stereotactic Body Radiotherapy in Patients with Emphysema Who Had Stage I Non-small Cell Lung Cancer.  Radiological Society of North America 2013 Scientific Assembly and Annual Meeting, December 1 - December 6, 2013 ,Chicago IL. http://archive.rsna.org/2013/13041334.html