Feasibility of omitting the clinical target volume under PET-CT guidance in unresectable stage III non-small-cell lung cancer: A phase II clinical trial. (April 2023)

• Record Type: Journal Article
• Authors: Cui, Tianxiang; Zhang, Anmei; Cui, Jianxiong; Chen, Lu; Chen, Guangpeng; Dai, Hongya; Qin, Xianli; Li, Guanghui; Sun, Jianguo
• Is Part Of: Radiotherapy and oncology. Volume 181(2023)
• Publication Date: 2023-04
• Subjects: Unresectable NSCLC -- CTV -- PET-CT -- Concurrent radiochemotherapy; Oncology -- Periodicals; Radiotherapy -- Periodicals; Tumors -- Periodicals; Medical Oncology -- Periodicals; Neoplasms -- radiotherapy -- Periodicals; Radiotherapy -- Periodicals; Radiothérapie -- Périodiques; Cancérologie -- Périodiques; Tumeurs -- Périodiques; Electronic journals; 616.9940642
• DOI: 10.1016/j.radonc.2023.109505
• Languages: English
• ISSNs: 0167-8140

Abstract

Highlights: This study adopted the precise positioning method combining PET-CT and 4D-CT, and explored the feasibility of CTV-omitted under the guidance of precise positioning combined with PET-CT and 4D-CT. The results showed that CTV-omitted can effectively reduce the incidence of radiation esophagitis and radiation pneumonitis in patients with stage III NSCLC without compromising survival. Abstract: Background: This clinical trial aims at investigate the feasibility of CTV-omitted, positron-emission tomography computed tomography (PET-CT) combined with intensity-modulated radiation therapy (IMRT) for unresectable stage III NSCLC. Methods and Materials: This was a single-center, phase II clinical trial initiated in July 2016. Patients with unresectable stage III NSCLC undergoing routine IMRT were randomly enrolled into the study group (CTV-omitted under PET-CT guidance) and the control group (CTV-delineated). Patients received platinum-based dual-drug concurrent chemoradio therapy. In the study group, the PGTV dose was 60 Gy given in 30 daily 2 Gy fractions; in the control group, the PCTV dose was 54 Gy given in 30 daily 1.8 Gy fractions, and the PGTV dose was 60 Gy given in 30 daily 2 Gy fractions. The primary endpoint was the incidence of radiation respiratory events or esophagitis with grade 3 or higher. The secondary endpoints included objective response rate (ORR), locate control rate, progression-free survival (PFS), failure pattern and overall survival (OS). Results: A total of 90 patients were enrolled between July 2016 and March 2019. The incidence of radiation respiratory events or esophagitis with grade 3 or higher was 11.1 % in the study group, significantly lower than the rate of 28.9 % in the control group (P = 0.035), basically due to the reduced irradiated volumes of the lungs and esophagus in the study group. The median PFS was 9.0 months versus 10.0 months (P = 0.597), and the median OS 31.0 months versus 26.0 months (P = 0.489) in the study group and the control group, respectively. The failure pattern was not significantly different between the two groups (P = 0.826). Conclusion: Omitting the CTV under PET-CT guidance has high feasibility to reduce severe radiation associated toxicity in IMRT for unresectable stage III NSCLC, without compromising the efficacy.