IMPORTANCEThe role of postoperative radiotherapy (PORT) has not been well defined in resected pIIIA-N2 non-small cell lung cancer (NSCLC).OBJECTIVE To evaluate the effect of PORT using modern techniques on survival and safety in patients with pIIIA-N2 NSCLC after complete resection and adjuvant chemotherapy. DESIGN, SETTING, AND PARTICIPANTS The PORT-C randomized clinical trial was conducted in 394 patients with pIIIA-N2 NSCLC treated with complete resection and 4 cycles of platinum-based chemotherapy between January 2009 and December 2017. Data were analyzed between March 2019 and December 2020. INTERVENTIONS Patients were randomized equally into the PORT arm (n = 202) or the observation arm (n = 192). The total dose of PORT was 50 Gy. MAIN OUTCOMES AND MEASURESThe primary end point was disease-free survival (DFS). Secondary end points included overall survival (OS), locoregional recurrence-free survival (LRFS), distant metastasis-free survival, and toxic effects.RESULTS In total, 394 patients were enrolled and 364 were eligible, with a median (range) age of 55 (25-70) years. There were 202 (55.5%) male and 162 (44.5%) female patients. The median follow-up was 46.0 (95% CI, 41.9-51.4) months, and 230 DFS events were reported. There were 184 patients in the PORT arm and 180 patients in the observation arm. The 3-year DFS rates were 40.5% with PORT vs 32.7% with observation (median, 22.1 vs 18.6 months), and the difference in DFS was not statistically significant without adjustment (hazard ratio [HR], 0.84; 95% CI, 0.65-1.09; P = .20), though it was significant with preplanned yet exploratory analysis (stratified analysis by the number of detected lymph nodes and positive lymph nodes, HR, 0.75; log-rank P = .04). The 3-year OS rates were 78.3% vs 82.8% (HR, 1.02; P = .93), and LRFS was 66.5% vs 59.7% (HR, 0.71; 95% CI, 0.51-0.97; P = .03), respectively. For 310 per-protocol patients (140 with PORT and 170 with observation), PORT significantly improved DFS (42.8% vs 30.6%; HR, 0.75; 95% CI, 0.57-1.00; P = .05) but not OS (HR, 0.83; 95% CI, 0.53-1.30; P = .41). The 3-year local recurrence only rates were 9.5% and 18.3% in the 2 arms, respectively (Fine-Gray HR, 0.55; Gray test P = .04). No radiotherapy-related grade 4 or 5 adverse event was observed. CONCLUSIONS AND RELEVANCEIn this phase 3 randomized clinical trial of patients with pIIIA-N2 NSCLC after complete resection and adjuvant chemotherapy, PORT did not improve DFS. Further studies exploring patients who might best benefit from PORT are needed.TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT00880971

NCT01494558.

Radiation pneumonitis (RP) is one of the major toxicities of thoracic radiation therapy. RP incidence has been proven to be closely associated with the dosimetric factors and normal tissue control possibility (NTCP) factors. However, because these factors only utilize limited information of the dose distribution, the prediction abilities of these factors are modest. We adopted the dosiomics method for RP prediction. The dosiomics method first extracts spatial features of the dose distribution within ipsilateral, contralateral, and total lungs, and then uses these extracted features to construct prediction model via univariate and multivariate logistic regression (LR). The dosiomics method is validated using 70 non-small cell lung cancer (NSCLC) patients treated with volumetric modulated arc therapy (VMAT) radiotherapy. Dosimetric and NTCP factors based prediction models are also constructed to compare with the dosiomics features based prediction model. For the dosimetric, NTCP and dosiomics factors/features, the most significant single factors/features are the mean dose, parallel/serial (PS) NTCP and gray level co-occurrence matrix (GLCM) contrast of ipsilateral lung, respectively. And the area under curve (AUC) of univariate LR is 0.665, 0.710 and 0.709, respectively. The second significant factors are V 5 of contralateral lung, equivalent uniform dose (EUD) derived from PS NTCP of contralateral lung and the low gray level run emphasis of gray level run length matrix (GLRLM) of total lungs. The AUC of multivariate LR is improved to 0.676, 0.744, and 0.782, respectively. The results demonstrate that the univariate LR of dosiomics features has approximate predictive ability with NTCP factors, and the multivariate LR outperforms both the dosimetric and NTCP factors. In conclusion, the spatial features of dose distribution extracted by the dosiomics method effectively improves the prediction ability.

After completing this course, the reader will be able to:1. Describe the present clinical practice and controversies regarding the use of PORT in resected pIIIA-pN2 NSCLC.2. Evaluate the effect of PORT on overall survival and on tumor control in this subgroup of patients.This article is available for continuing medical education credit at CME.TheOncologist.com. CME CME ABSTRACTBackground. For patients with resected pathological stage IIIA-N2 non-small cell lung cancer (NSCLC), the role of postoperative radiotherapy (PORT) is not well defined. In this single-institutional study, we re-evaluated the effect of PORT on overall survival (OS) as well as tumor control in this subgroup of patients.

BACKGROUND:The authors conducted a retrospective study to evaluate the effects of thoracic radiation therapy (TRT) for patients with extensive-stage small cell lung cancer (ED-SCLC). METHODS: Between January 2003 and December 2006, the records of 119 patients who were diagnosed with ED-SCLC (all with distant metastasis [M1]) were included in the study. Sixty patients received chemotherapy (ChT) and TRT (ChT/TRT), and 59 patients received ChT alone. The ChT regimens consisted of either carboplatin and etoposide (CE) or cisplatin and etoposide (PE). The total dose of TRT ranged from 40 to 60 grays (Gy) at 1.8 to 2.0 Gy per fraction. RESULTS: For the entire group, the median survival was 13 months, and the 2-year and 5-year overall survival (OS) rates were 26.1% and 6.5%, respectively. The median survival and the 2-year and 5-year OS rates were 17 months, 35%, and 7.1%, respectively, in the ChT/TRT group and 9.3 months, 17%, and 5.1%, respectively, in the ChT group (P ¼ .014). However, this improvement was achieved at the expense of low toxicity. Multivariate analysis revealed that receiving 4 cycles of ChT (P ¼ .032) and TRT (P ¼ .005) were favorable prognostic factors for OS. Of all toxicities, only high-grade leucopenia (grade >3) was more frequent in the ChT/TRT group. CONCLUSIONS: The addition of TRT to ChT improved the OS of patients with ED-SCLC. Furthermore, receiving 4 cycles of ChT and TRT were independent, favorable prognostic factors for OS.