Postoperative Radiotherapy for Patients With Resectable Stage III-N2 Non-Small Cell Lung Cancer: A Systematic Review and Meta-Analysis

Clinical impact of postoperative radiotherapy in pIII-N2 non-small cell lung cancer after complete resection followed by adjuvant chemotherapy: a systematic review and meta-analysis

Background

Theoretically, postoperative radiotherapy (PORT) could reduce the risk of local recurrence and further improve survival outcomes. This study aimed to evaluate the clinical impact of PORT on patients with pIII-N2 non-small cell lung cancer (NSCLC) after complete resection followed by adjuvant chemotherapy.

Methods

A systematic literature search was performed in November 2022 to identify randomized controlled trials (RCTs) that compare PORT with observation in patients with pIII-N2 NSCLC using PubMed, Embase, and the Cochrane Central Register of Controlled Trials. This meta-analysis is in accordance with the recommendations of the PRISMA statement. The main outcomes were overall survival (OS), disease-free survival (DFS), and local recurrence rates, which were compared using hazard ratios (HRs).

Results

Five RCTs involving 1,138 patients were included: 572 patients in the PORT group and 566 patients in the observation group. The methodological quality of the five RCTs was high. Pooled analysis revealed that PORT decreased local recurrence rate [odds ratio =0.53, 95% confidence interval (CI): 0.40-0.70]. However, PORT did not improve median DFS (HR =0.93, 95% CI: 0.80-1.08) and OS (HR =0.94, 95% CI: 0.78-1.14).

Conclusions

Compared to adjuvant chemotherapy alone, additional PORT was significantly associated with a reduced local recurrence rate. However, neither DFS nor OS benefited from PORT in patients with pIII-N2 NSCLC who had undergone complete resection.

Development and validation of a nomogram for predicting overall survival in patients with stage III-N2 lung adenocarcinoma based on the SEER database

Background

There is variability in the prognosis of stage III-N2 lung adenocarcinoma (LUAD) patients. The current tumor-node-metastasis (TNM) staging is not sufficient to precisely estimate the prognosis of stage III-N2 LUAD patients. The Surveillance, Epidemiology, and End Results (SEER) database collected first-hand information from a large number of LUAD patients. Based on the SEER database, this study aimed to determine the prognostic factors that affect overall survival (OS) in stage III-N2 LUAD patients and then establish a nomogram for predicting OS in this type of cancer to identify the high-risk population that may require more frequent surveillance or intensive care.

Methods

Data for 1,844 stage III-N2 primary LUAD patients who were registered between 2010 and 2015 were obtained from the SEER database. These patients were randomly assigned to either training (n=1,290) or validation (n=554) cohorts at a 7:3 ratio. The univariate and multivariate Cox regression (UCR and MCR) analyses were performed to find the relevant independent prognostic factors. To predict the OS based on these prognostic factors, a nomogram was then developed. The performance of the nomogram was examined based on the calibration curves, and receiver operating characteristic (ROC) curves. The ability of nomogram to stratify patient risk was validated by Kaplan-Meier survival analysis.

Results

Age, gender, tumor location, T-stage and treatment modality (chemotherapy, radiation therapy, surgery and scope of lymph node dissection) of stage III-N2 LUAD patients were significantly associated with prognosis. The area under the curve (AUC) values of OS predicted by the nomogram constructed with these factors at 12-, 36- and 60-month were 0.784, 0.762 and 0.763 in the training cohort, whereas 0.707, 0.685 and 0.705 in the validation cohort, respectively. Additionally, calibration curves demonstrated concordance between predicted and observed outcomes. Nomogram risk stratification provides a meaningful distinction between patients with various survival risks.

Conclusions

A survival prediction model that may be useful for risk stratification and decision-making is developed and validated for stage III-N2 LUAD patients. A high-risk patient predicted by the prediction model may require more frequent surveillance or intensive care.

Effect of postoperative radiotherapy on survival in patients with completely resected and pathologically confirmed stage N2 non-small-cell lung cancer: a systematic review and meta-analysis

Background

The role of postoperative radiotherapy (PORT) for patients with completely resected stage N2 non-small-cell lung cancer (NSCLC) has been controversial. This study aimed to investigate the efficacy of PORT and prognosis in these patients.

Objectives

An updated meta-analysis was conducted in this study to investigate the efficacy of PORT and prognosis in patients with completely resected and pathologically confirmed stage N2 NSCLC.

Design

This study is a systematic review and meta-analysis.

Data source and methods

Databases were searched up to 2 March 2022. All trials on patients with completely resected and pathologically confirmed stage N2 NSCLC undergoing PORT were screened, and data indicators in the PORT and non-PORT groups were extracted, respectively. The effect of PORT on overall survival (OS), disease-free survival (DFS), local recurrence-free survival (LRFS), and distant metastasis-free survival (DMFS) was estimated. Subgroup and sensitivity analyses were performed.

Results

In all, 20 studies involving 6340 patients were finally included. The PORT significantly increased OS [hazard ratio (HR) = 0.77, 95% CI: 0.71-0.84, p < 0.001), LRFS (HR = 0.63, 95% CI: 0.52-0.76, p < 0.001), and DFS (HR = 0.72, 95% CI: 0.63-0.82, p < 0.001) while it showed no significant difference in improving DMFS (HR = 0.86, 95% CI: 0.71-1.05, p = 0.14).

Conclusion

Our results suggest that in the postoperative treatment of patients with completely resected and pathologically confirmed stage N2 NSCLC, the addition of PORT provides better local recurrence control and survival benefit, but no benefit for distant metastases. The PORT may be incorporated into the postoperative treatment options for some patients with high-risk factors. However, it needs to be validated by more prospective studies in the future.

Trail registration

CRD42022314095.

The high-risk features and effect of postoperative radiotherapy on survival for patients with surgically treated stage IIIA-N2 non-small cell lung cancer

OBJECTIVES

Although postoperative radiotherapy (PORT) could reduce the incidence of local recurrence in patients with IIIA-N2 non-small cell lung cancer (NSCLC), the role of PORT on survival in patients with surgically treated stage IIIA-N2 NSCLC remains controversial. Therefore, this study was designed to evaluate the effect of PORT on survival for patients with surgically treated stage IIIA-N2 NSCLC.

MATERIALS AND METHODS

This study population was chosen from the Surveillance, Epidemiology, and End Results database. The Cox proportional hazards regression analysis was used to determine significant contributors to overall survival (OS) and cancer special survival (CSS) outcomes. To balance baseline characteristics between the non-PORT group and PORT group, propensity score matching (PSM) with 1:1 propensity nearest-neighbor match by 0.001 matching tolerance was conducted by R software. Furthermore, a Kaplan-Meier curve was used to visualize the OS and CSS between the PORT group and non-PORT group survival probability.

RESULTS

Of all evaluated cases, 4511 with IIIA-N2 NSCLC were eligible for inclusion, of which 1920 were enrolled into the PORT group. On univariate analysis and multivariate analysis, sex, age, year of diagnosis, race, histologic type, T stage, PORT, use of chemotherapy, and positive regional nodes were significantly associated with OS and CSS in IIIA-N2 NSCLC (P < 0.05). However, PORT was not significantly associated with OS (univariate HR = 0.92, 95%CI 0.85-0.99, P = 0.02; multivariate HR = 1.01, 95%CI 0.93-1.08, P = 0.91) and CSS (univariate HR = 0.92, 95%CI 0.85-1.01, P = 0.06; multivariate HR = 1.103 95%CI 0.94-1.12, P = 0.56) in IIIA-N2 NSCLC. Meanwhile, after PSM, neither OS nor CSS did differ significantly between the non-PORT group and PORT group (OS HR = 1.08, 95%CI 0.98-1.19, P = 0.12; CSS HR = 1.10, 95%CI 0.99-1.23, P = 0.07).

CONCLUSION

PORT did not contribute to a survival benefit in patients with surgically treated stage IIIA-N2 NSCLC.

Uncertain resection of highest mediastinal lymph node positive among pN2 non-small cell lung cancer patients: survival analysis of postoperative radiotherapy and driver gene mutations

BACKGROUND AND PURPOSE

The role of postoperative radiotherapy (PORT) in uncertain resection of pN2 non-small cell lung cancer (NSCLC) with highest mediastinal lymph node positive has not been determined. We aim to evaluate the effect of PORT and driver gene mutation status (DGMS) on survival in such patients.

METHODS

140 selected patients were grouped according to whether they received PORT and their DGMS. Locoregional recurrence-free survival (LRFS), distant metastasis-free survival (DMFS), disease-free survival (DFS), and overall survival (OS) of each group were evaluated by Kaplan-Meier analyses. COX regression was used to evaluate the effects of various factors on DFS and OS.

RESULTS

Of 140 patients, thirty-four patients (24.3%) received PORT, and forty (28.6%) had positive driver gene mutation status (DGp). PORT significantly prolonged LRFS (p = 0.002), DFS (p = 0.019) and OS (p = 0.02), but not DMFS (p = 0.062). By subgroup analysis, in patients with negative driver gene mutation status (DGn), those receiving PORT had notably longer LRFS (p = 0.022) and DFS (p = 0.033), but not DMFS (p = 0.060) or OS (p = 0.215), compared to those not receiving PORT. Cox analysis showed that the number of positive lymph nodes (PLNs) and administration of PORT were independent prognostic factors of DFS, and pathology, PLNs, and DGMS may be prognostic factors of OS (all p < 0.05).

CONCLUSION

Postoperative radiotherapy may improve locoregional recurrence-free and disease-free survival in patients with pN2 NSCLC with positive highest mediastinal lymph nodes, while driver gene mutation status impacted OS significantly. Only patients with positive driver gene mutations experienced significant overall survival benefits from postoperative radiotherapy.

Cardiac Adverse Events Associated With Chemo-Radiation Versus Chemotherapy for Resectable Stage III Non-Small-Cell Lung Cancer: A Surveillance, Epidemiology and End Results-Medicare Study

Background We compared cardiac outcomes for surgery-eligible patients with stage III non-small-cell lung cancer treated adjuvantly or neoadjuvantly with chemotherapy versus chemo-radiation therapy in the Surveillance, Epidemiology and End Results-Medicare database. Methods and Results Patients were age 66+, had stage IIIA/B resectable non-small-cell lung cancer diagnosed between 2007 and 2015, and received adjuvant or neoadjuvant chemotherapy or chemo-radiation within 121 days of diagnosis. Patients having chemo-radiation and chemotherapy only were propensity-score matched and followed from day 121 to first cardiac outcome, noncardiac death, radiation initiation by patients who received chemotherapy only, fee-for-service enrollment interruption, or December 31, 2016. Cause-specific hazard ratios (HRs) and competing risks subdistribution HRs were estimated. The primary outcome was the first of these severe cardiac events: acute myocardial infarction, other hospitalized ischemic heart disease, hospitalized heart failure, percutaneous coronary intervention/coronary artery bypass graft, cardiac death, or urgent/inpatient care for pericardial disease, conduction abnormality, valve disorder, or ischemic heart disease. With median follow-up of 13 months, 70 of 682 patients who received chemo-radiation (10.26%) and 43 of 682 matched patients who received chemotherapy only (6.30%) developed a severe cardiac event (P=0.008) with median time to first event 5.45 months. Chemo-radiation increased the rate of severe cardiac events (cause-specific HR: 1.62 [95% CI, 1.11-2.37] and subdistribution HR: 1.41 [95% CI, 0.97-2.04]). Cancer severity appeared greater among patients who received chemo-radiation (noncardiac death cause-specific HR, 2.53 [95% CI, 1.93-3.33] and subdistribution HR, 2.52 [95% CI, 1.90-3.33]). Conclusions Adding radiation therapy to chemotherapy is associated with an increased risk of severe cardiac events among patients with resectable stage III non-small-cell lung cancer for whom survival benefit of radiation therapy is unclear.

Lymph node ratio predicts overall survival in patients with stage II non-small cell lung cancer: a population-based SEER analysis

BACKGROUND

In non-small-cell lung cancer (NSCLC), there are many factors that affect prognosis, and the lymph node ratio (LNR) may play a significant role. Our study aimed to confirm the value of the LNR in the prognosis of patients with stage II NSCLC.

METHODS

Patient data were obtained from the Surveillance, Epidemiology and End Results (SEER) database. The classification for the LNR was best determined using the X-tile method. The correlation between the LNR and overall survival (OS) was validated after the Kaplan-Meier analysis was performed. To determine the correlation between the LNR and survival, stratification and the Cox regression analysis were used.

RESULTS

In our study, 14,183 stage II NSCLC patients were included. Among them, 8303 patients had N1 disease. According to the X-tile analysis, the optimal critical points for the LNR in N1 patients with NSCLC was 0.21 and 0.38. We categorized the cohorts as low (LNR-L ≤ 0.21; n = 5158, 62.1%), medium (0.21 < LNR-M ≤ 0.38; n = 1736, 20.9%), and high (LNR-H > 0.38; n = 1409, 17.0%). According to the Kaplan-Meier analysis, the patients with a high LNR were considerably worse than those with a medium or low LNR (P < 0.001), which was also proven by stratified and multivariate analyses. The value of the LNR was reflected in all the subgroup analyses, especially in patients ages < 60 years. The multivariate competing risks regression analysis revealed that younger age, female sex, T1 disease, adenocarcinoma and N0 disease was associated with a better prognosis after controlling for potential confounders (P < 0.001).

CONCLUSIONS

For patients with stage II NSCLC, the LNR is valuable for assessing prognosis. A higher LNR indicates a worse prognosis.

Postoperative radiotherapy in pIIIA-N2 non-small cell lung cancer after complete resection and adjuvant chemotherapy: A meta-analysis

BACKGROUND

This study aimed to evaluate the effect of postoperative radiotherapy (PORT) in patients with pIIIA-N2 non-small cell lung cancer after complete resection and adjuvant chemotherapy.

METHODS

Electronic databases (PubMed, Web of Science databases, Embase, and the Cochrane Central Register of Controlled Trials) were systematically searched to extract randomized control trials comparing PORT with observation in pIIIA-N2 non-small cell lung cancer patients until October 2021. Main outcomes were disease-free survival (DFS), overall survival (OS), and local recurrence.

RESULTS

Three-phase 3 randomized control trials involving 902 patients were included: 455 patients in the PORT group and 447 patients in the observation group. The methodological quality of the 3 randomized control trials were high quality. The pooled analysis revealed that PORT decreased local recurrence rate (odds ratio = 0.56, 95% confidence interval [CI]: 0.40-0.76). However, PORT did not improve median DFS (hazard ratio = 0.84, 95% CI: 0.71-1.00) and OS (hazard ratio = 1.02, 95% CI: 0.68-1.52).

CONCLUSIONS

PORT decreased the incidence of local recurrence. However, PORT did not improve DFS and OS.

Predictive Risk Factors for Early Recurrence of Stage pIIIA-N2 Non-Small Cell Lung Cancer

Purpose

Inflammatory biomarkers and clinical pathological factors have been reported to predict survival of patients with non-small cell lung cancer (NSCLC). The goal of this study was to identify risk factors for early recurrence in patients with pIIIA-N2 NSCLC who had undergone radial resection.

Methods

A retrospective analysis was conducted on 238 patients with pIIIA-N2 NSCLC who underwent surgical treatment at the First Affiliated Hospital of Wenzhou Medical University between December 2006 and August 2018. The early recurrence (ER) group included patients who recurred within one year of curative resection, while the non-early recurrence (NER) group included patients who did not recurrence or recurrence beyond one year. The univariate and multivariate Cox proportional risk analyses were used to identify prognostic factors associated with early recurrence, while the chi-square test was used for categorical data. Overall survival and recurrence-free survival were assessed by Kaplan–Meier estimates.

Results

A total of 69 patients experienced an early recurrence, while the remaining 169 patients did not relapse within one year. ER patients had a much worse prognosis than NER patients, with median survival times of 20.6 and 83.1 months, respectively. Multivariate analysis showed that smoking status, tumor size, metastatic lymph node ratio (LNR) and platelet-to-lymphocyte ratio (PLR) were independent risk factor of early recurrence. Patients with early recurrence were more likely to develop bone metastases.

Conclusion

Smoking history, large tumour size, and elevated LNR and PLR values in pIIIA-N2 NSCLC patients after complete resection may have a significant risk of early recurrence. Based on these independent risk indicators, this prediction model may successfully predict early recurrence and advise individual treatment.