Impact of salvage radiotherapy on survival of patients with advanced locally recurrent nasopharyngeal carcinoma: Derivation and validation of a predictive model. (February 2022)

• Record Type: Journal Article
• Authors: Liu, Ting; Shen, Bo-Wen; Liu, Li-Ting; Yang, Zhen-Chong; Wang, Shi-Qian; Lin, Da-Feng; Sun, Xue-Song; Guo, Shan-Shan; Liu, Sai-Lan; Luo, Mei-Juan; Chen, Qiu-Yan; Tang, Lin-Quan; Mai, Hai-Qiang
• Is Part Of: Radiotherapy and oncology. Volume 167(2022)
• Page Start: 252
• Page End: 260
• Publication Date: 2022-02
• Subjects: ALB albumin -- BMI body mass index -- CI confidence interval -- CRP C-reactive protein -- DFI disease-free interval -- EBV Epstei-Barr virus -- ECOG PS Eastern Cooperative Oncology Group performance status -- HB hemoglobin -- HR Hazard ratio -- IMRT intensity modulated radiotherapy -- IPTW inverse probability of treatment weighting -- NPC Nasopharyngeal carcinoma -- OS overall survival -- PLT platelet -- RCT randomized controlled trial -- ROC receiver operating characteristic -- RT radiotherapy -- RTOG Radiation Therapy Oncology Group -- SARTOS Salvage Radiotherapy Outcome Score -- UICC/AJCC American Joint Committee on Cancer Union for International Cancer Control -- WBC white blood cell; Nasopharynageal carcinoma -- Salvage radiotherapy -- Overall survival -- Predictive model; 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.2021.12.046
• Languages: English
• ISSNs: 0167-8140

Abstract

Highlights: Salvage radiotherapy did not improve overall survival in advanced recurrent disease. Sex, prior toxicities and performance status predicted effects of re-irradiation. The proposed model could identify a patient subgroup to benefit from re-irradiation. Abstract: Background: Salvage radiotherapy (RT) is a potentially curative approach for advanced locally recurrent nasopharyngeal carcinoma (NPC), but it is associated with severe toxicities. We aimed to develop a model to predict which patients would benefit from salvage RT. Methods: A total of 809 patients who were diagnosed with advanced locally recurrent NPC and treated with salvage RT or palliative chemotherapy (CT) at a high-volume cancer center were included. Patients were randomly split into a training and validation set and matched using inverse probability of treatment weighting. The primary outcome was overall survival (OS). Candidate variables associated with heterogeneous treatment effects were identified with interaction terms in Cox model and incorporated into Salvage Radiotherapy Outcome Score (SARTOS). Results: The final model included five interaction terms indicating that female sex, presence of prior RT-induced grade ≥ 3 late toxicities and suboptimal performance status were associated with less benefit from salvage RT. SARTOS from the model significantly predicted treatment effects of salvage RT in matched training ( P interation < 0.001) and validation cohorts ( P interation = 0.027). Of patients in high SARTOS subgroup, salvage RT significantly improved survival versus palliative CT in matched training (3-year OS 67.3% vs. 42.0%, HR 0.51, 95% CI 0.32–0.82, P = 0.005) and validation cohorts (3-year OS 71.8% vs. 22.8%, HR 0.40, 95% CI 0.17–0.97, P = 0.042); in low SARTOS subgroup, salvage RT failed to induce survival benefit. Conclusions: We found that the SARTOS model could identify a subgroup of patients who benefit from salvage RT versus palliative CT, which helps personalize treatment recommendations for patients with recurrent NPC.