Since Chemotherapy Is Now the Standard in Node-Positive Lung Cancer, What Is the Role of Postoperative Radiotherapy?

Propensity score-matching analysis of postoperative radiotherapy for stage IIIA-N2 non-small cell lung cancer using the Surveillance, Epidemiology, and End Results database

Background

To investigate the effects of postoperative radiotherapy (PORT) on the survival of patients with resected stage IIIA-N2 non-small cell lung cancer (NSCLC).

Methods

A total of 3,334 patients with resected stage IIIA-N2 NSCLC in 2004 to 2013 were identified in the Surveillance, Epidemiology, and End Results database and stratified according to use of PORT. Propensity score-matching (PSM) methods were used to balance the baseline characteristics of patients who did (n = 744) or did not (n = 744) undergo PORT. Overall survival (OS) and lung cancer-specific survival (LCSS) were compared between these two patient groups.

Results

After PSM, PORT increased OS (hazard ratio, 0.793; p = 0.001) and LCSS (hazard ratio, 0.837; p = 0.022) compared with no PORT. The OS benefit for PORT was mainly seen in patients aged <60 years (5-year OS, 35.4% versus 28.9% for PORT versus no PORT, respectively; p = 0.026) and in those who underwent lobectomy (5-year OS, 43.5% versus 34.5% for PORT versus no PORT, respectively; p = 0.001). The LCSS benefit for PORT was significant in patients undergoing lobectomy (5-year LCSS, 48.3% versus 42.3% for PORT versus no PORT, respectively; p = 0.036).

Conclusions

The survival benefits of PORT were primarily observed in patients with resected stage IIIA-N2 NSCLC who were <60 years of age or had undergone lobectomy.

Efficacy of postoperative radiotherapy in patients with pathological stage N2 epidermal growth factor receptor wild type adenocarcinoma and squamous cell carcinoma lung cancer

PURPOSE

Few large, prospective, randomized studies have compared the effects of postoperative radiotherapy (PORT) in pathological N2 (pN2) with those of surgical resection alone. in terms of long-term survival in lung adenocarcinoma (adenoCA; wild-type [WT] epidermal growth factor receptor [EGFR]) and squamous cell carcinoma (squCA) settings. This nationwide cohort study clarifies the role of PORT in the survival of pN2 lung adenoCA (WT EGFR) and squCA patientsPatients and Methods: We analyzed data of patients with adenoCA (WT EGFR) and squCA collected from the Taiwan Cancer Registry database. The patients were categorized into five groups according to the treatment modality: Group 1 (surgery alone), Group 2 (adjuvant chemotherapy [CT] alone), Group 3 (adjuvant radiotherapy [RT] alone), Group 4 (adjuvant concurrent chemoradiotherapy [CCRT]), and Group 5 (adjuvant sequential CT and intensity-modulated RT [IMRT]).

RESULTS

We enrolled 588 lung adenoCA (WT EGFR) and squCA patients without distant metastasis. After adjustments for age at surgery, surgical years, and Charlson comorbidity index scores, the multivariate Cox regression analysis demonstrated that adjusted HRs (aHRs; 95% confidence intervals [CIs]) for the overall mortality of female lung adenoCA (WT EGFR) patients were 0.257 (0.111-0.594), 0.530 (0.226-1.243), 0.192 (0.069-0.534), and 0.399 (0.172-0.928) in Groups 2, 3, 4, and 5, respectively. For male lung squCA patients, the aHRs (95% CIs) for overall mortality were 0.269 (0.160-0.451), 0.802 (0.458-1.327), 0.597 (0.358-0.998), and 0.456 (0.265-0.783) in Groups 2, 3, 4, and 5, respectively.

CONCLUSIONS

Adjuvant CCRT or sequential CT and IMRT at ≥5000 cGy significantly reduced the mortality rate of female lung adenoCA (WT EGFR) and male squCA pN2 patients.

The risk of death from heart disease in patients with nonsmall cell lung cancer who receive postoperative radiotherapy: analysis of the Surveillance, Epidemiology, and End Results database

BACKGROUND

This study was designed to investigate whether the mortality from heart disease, a manifestation of intercurrent disease after postoperative radiotherapy (PORT), has decreased over time for patients with nonsmall cell lung cancer (NSCLC).

METHODS

The 17-registry 1973 to 2003 dataset from the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) Program was used to create a cohort of patients with NSCLC who had evidence of ipsilateral lymph node involvement diagnosed from 1983 to 1993 and who underwent pnuemonectomy/lobectomy (n = 6148 patients). Heart disease mortality was the primary endpoint: Deaths from other causes were censored, and surviving patients were censored at 10 years. The independent variable was PORT use, and adjustment variables included age at diagnosis, sex, race, year of diagnosis, laterality, location, histology, and the operation performed.

RESULTS

Multivariate analysis revealed that PORT use was associated with an increase in heart disease mortality (hazards ratio [HR], 1.30; 95% confidence interval [95% CI], 1.04-1.61; P = .0193) along with older age, male sex, African-American race, and earlier year of diagnosis. The association was confirmed in the cohort that was diagnosed from 1983 to 1988 (HR, 1.49; 95% CI, 1.11-2.01 [P = .0090]) but not for the cohort that was diagnosed from 1989 to 1993 (HR, 1.08; 95% CI, 0.79-1.48 [P = .6394]).

CONCLUSIONS

The results from this study demonstrated that the risk of heart disease mortality associated with PORT has declined in more recent years. This may be secondary to improvements in the treatment planning and delivery of thoracic radiotherapy. Properly designed, prospective, adjuvant trials will be needed to verify these findings.