{Reference Type}: Journal Article {Title}: Early Identification of Pneumonitis in Patients Irradiated for Lung Cancer-Final Results of the PARALUC Trial. {Author}: Rades D;Werner EM;Glatzel E;Bohnet S;Schild SE;Tvilsted SS;Janssen S; {Journal}: Cancers (Basel) {Volume}: 15 {Issue}: 2 {Year}: Jan 2023 4 {Factor}: 6.575 {DOI}: 10.3390/cancers15020326 {Abstract}: Radiotherapy of lung cancer may cause pneumonitis that generally occurs weeks or months following therapy and can be missed. This prospective trial aimed to pave the way for a mobile application (app) allowing early diagnosis of pneumonitis. The primary goal was the identification of the optimal cut-off of a score to detect pneumonitis of grade ≥2 after radiotherapy for lung cancer. Based on the severity of symptoms (cough, dyspnea, fever), scoring points were 0−9. Receiver operating characteristic (ROC)-curves were used to describe the sensitivity and specificity. The area under the ROC-curve (AUC) was calculated to judge the accuracy of the score, Youden-index was employed to define the optimal cut-off. Until trial termination, 57 of 98 patients were included. Eight of 42 patients evaluable for the primary endpoint (presence or absence of radiation pneumonitis) experienced pneumonitis. AUC was 0.987 (0.961−1.000). The highest sensitivity was achieved with 0−4 points (100%), followed by 5 points (87.5%), highest specificity with 5−6 points (100%). The highest Youden-index was found for 5 points (87.5%). The rate of patient satisfaction with the symptom-based scoring system was 93.5%. A cut-off of 5 points was identified as optimal to differentiate between pneumonitis and no pneumonitis. Moreover, pneumonitis was significantly associated with an increase of ≥3 points from baseline (p < 0.0001). The scoring system provided excellent accuracy and high patient satisfaction. Important foundations for the development of a mobile application were laid.