Journal Article

High-dose thoracic radiation therapy for non-small cell lung cancer: a novel grading scale of radiation-induced lung injury for symptomatic radiation pneumonitis

Takács-Szabó, Zsuzsanna, Al-Saadi, Sahar Sulaiman, McCulloch, Tine, Falkmer, Ursula Gerda, Maidas, Panagiotis, Pawlowski, Jacek, Bøgsted, Martin, Nielsen, Martin Skovmos, Frøkjær, Jens Brøndum, Szejniuk, Weronika Maria, Røe, Oluf Dimitri

2021

Overview

Background Symptomatic radiation pneumonitis (RP) may be a serious complication after thoracic radiation therapy (RT) for non-small cell lung cancer (NSCLC). This prospective observational study sought to evaluate the utility of a novel radiation-induced lung injury (RILI) grading scale (RGS) for the prediction of RP. Materials and methods Data of 41 patients with NSCLC treated with thoracic RT of 60–66 Gy were analysed. CT scans were scheduled before RT, one month post-RT, and every three months thereafter for one year. Symptomatic RP was defined as Common Terminology Criteria for Adverse Events grade ≥ 2. RGS grading ranged from 0 to 3. The inter-observer variability of the RGS was assessed by four senior radiologists. CT scans performed 28 ± 10 days after RT were used to analyse the predictive value of the RGS. The change in the RGS severity was correlated to dosimetric parameters. Results The CT obtained one month post-RT showed RILI in 36 (88%) of patients (RGS grade 0 [5 patients], 1 [25 patients], 2 [6 patients], and 3 [5 patients]). The inter-observer agreement of the RGS grading was high (Kendall’s W coefficient of concordance = 0.80, p  < 0.01). Patients with RGS grades 2–3 had a significantly higher risk for development of RP (relative risk (RR): 2.4, 95% CI 1.6–3.7, p  < 0.01) and RP symptoms within 8 weeks after RT (RR: 4.8, 95% CI 1.3–17.6, p  < 0.01) compared to RGS grades 0–1. The specificity and sensitivity of the RGS grades 2–3 in predicting symptomatic RP was 100% (95% CI 80.5–100%) and 45.4% (95% CI 24.4–67.8%), respectively. Increase in RGS severity correlated to mean lung dose and the percentage of the total lung volume receiving 5 Gy. Conclusions The RGS is a simple radiologic tool associated with symptomatic RP. A validation study is warranted.

• Publisher: BioMed Central,BioMed Central Ltd,Springer Nature B.V,BMC
• Subject: Adult / Aged / Antibiotics / Bacterial pneumonia / Biomedical and Life Sciences / Biomedicine / Cancer Research / Cancer therapies / Carcinoma, Non-Small-Cell Lung - pathology / Carcinoma, Non-Small-Cell Lung - radiotherapy / Care and treatment / Clinical Radiation Oncology / Complications and side effects / Computed tomography / Development and progression / Dose-response relationship (Biochemistry) / Female / Humans / Image Processing, Computer-Assisted - methods / Imaging / Lung cancer / Lung cancer, Non-small cell / Lung Injury - etiology / Lung Injury - pathology / Lung Neoplasms - pathology / Lung Neoplasms - radiotherapy / Male / Medical imaging / Middle Aged / Non-small cell lung cancer radiation therapy / Non-small cell lung carcinoma / Observer Variation / Oncology / Organs at Risk - radiation effects / Patients / Pleural effusion / Pneumonia / Pneumonitis / Prognosis / Prospective Studies / Radiation / Radiation dosage / Radiation effects / Radiation injuries / Radiation pneumonitis / Radiation Pneumonitis - etiology / Radiation Pneumonitis - pathology / Radiation therapy / Radiation therapy toxicity / Radiation-induced lung injury / Radiation-related pulmonary toxicity / Radiological radiation-induced lung injury scale / Radiology / Radiometry - methods / Radiotherapy / Radiotherapy Dosage / Radiotherapy, Intensity-Modulated - adverse effects / Small cell lung carcinoma / Terminology / Thorax / Variance analysis