Postoperative chemotherapy significantly improves survival of elderly patients with stage IB-II non-small cell lung cancer: A population-based study

Is there a prognostic difference among stage I lung adenocarcinoma patients with different BRAF-mutation status?

BACKGROUND

The data of the prognostic role of V-Raf murine sarcoma viral oncogene homolog B1 (BRAF) mutations in early-stage lung adenocarcinoma (LUAD) patients is scarce. This study aimed to investigate the proportion, clinicopathological features, and prognostic significance of patients with stage I LUAD carrying BRAF mutations.

METHODS

We collected 431 patients with pathological stage I LUAD from cBioPortal for Cancer Genomics and 1604 LUAD patients tested for BRAF V600E and epidermal growth factor receptor (EGFR) mutations from Shanghai Pulmonary Hospital. Survival curves were drawn by the Kaplan-Meier method and compared by log-rank test. Cox proportional hazard models, propensity-score matching (PSM), and overlap weighting (OW) were performed in this study. The primary endpoint was recurrence-free survival (RFS).

RESULTS

The proportion of BRAF mutations was estimated at 5.6% in a Caucasian cohort. BRAF V600E mutations were detected in six (1.4%) patients in Caucasian populations and 16 (1.0%) patients in Chinese populations. Two BRAF V600E-mutant patients were detected to have concurrent EGFR mutations, one for 19-del and one for L858R. For pathological stage I LUAD patients, BRAF mutations were not significantly associated with worse RFS than wild-type BRAF patients (HR = 1.111; p = 0.885). After PSM and OW, similar results were presented (HR = 1.352; p = 0.742 and HR = 1.246; p = 0.764, respectively). BRAF V600E mutation status also lacked predictive significance for RFS (HR, 1.844; p = 0.226; HR = 1.144; p = 0.831 and HR = 1.466; p = 0.450, respectively).

CONCLUSIONS

In this study, we demonstrated that BRAF status may not be capable of predicting prognosis in stage I LUAD patients. There is a need for more data to validate our findings.

Meta-analysis of the efficacy of postoperative adjuvant chemotherapy for stage IB non-small cell lung cancer

BACKGROUND

Many clinical trials have shown that postoperative adjuvant chemotherapy can provide a survival benefit for patients with stage IB non-small cell lung cancer. However, whether adjuvant chemotherapy should be routinely given after surgery remains controversial. Therefore, we performed a meta-analysis to investigate the efficacy of adjuvant chemotherapy versus surgery alone for stage IB non-small cell lung cancer (NSCLC).

METHODS

Relevant retrospective studies or randomized controlled trial comparing the efficacy of postoperative adjuvant chemotherapy versus observation on the survival outcomes of NSCLC patients up to October 30, 2023 were searched in PubMed, Web of Science, EMBASE, Cochrane Library, VIP database, Wanfang database, and China National Knowledge Internet database. Patient survival data, population characteristics, and other relevant information were extracted, and data were analyzed using Review Manager 5.4. The primary endpoints included overall survival, disease-free survival, and recurrence-free survival.

RESULTS

A total of 13 randomized controlled trials or cohort studies including 19,442 patients were included. The results of the meta-analysis showed that postoperative adjuvant chemotherapy in patients with stage IB NSCLC had better overall survival (odds ratio [OR] = 1.25, 95% confidence interval [CI] 1.19-1.31, P < .00001) and disease-free survival or recurrence-free survival (OR = 1.57, 95% CI 1.3-1.9, P < .00001) compared with observation; and the 4-year survival rate of patients who received postoperative adjuvant chemotherapy was better than the observation group (OR = 1.52, 95% CI 1.05-2.18, P = .03); and the 8-year survival rate of patients receiving postoperative adjuvant chemotherapy (OR = 1.5, 95% CI 0.94-2.4, P = .09) was comparable to the observation group.

CONCLUSION

Receiving postoperative adjuvant chemotherapy improved people's survival and prolonged disease-free survival and recurrence-free survival in patients with stage IB non-small cell lung cancer compared with surgery alone.