Adjuvant Chemotherapy Improves Survival in Surgically Resected Stage IB Squamous Lung Cancer

Abstract

Background. At present there is a significant lack of clinical data for patients with surgically resected stage I squamous lung cancer. The purpose of this study was to investigate the impact of postoperative chemotherapy in this specific population.Methods. We retrospectively identified patients who had undergone complete squamous lung cancer resection at the Shanghai Chest Hospital between January 2008 and January 2014.Results. A total of 596 patients (236 stage IA, 360 stage IB) were included in this study. Results demonstrated that adjuvant chemotherapy (ACT) could provide longer overall survival for patients with p-stage IB disease (hazard ratio [HR], 0.56; 95% confidence interval [CI], 0.34-0.90; p [ 0.017). Among p-stage IB patients the ACTtreated cohort trended toward a benefit (HR, 0.69; 95% CI, 0.45-1.04) in recurrence-free survival but failed to reach statistical significance (p [ 0.076). After propensity score matching the HRs of recurrence-free survival and overall survival were 0.58 (95% CI, 0.35-0.96; p [ 0.033) and 0.49 (95% CI, 0.27-0.88; p [ 0.017), respectively. With regards to patients with p-stage IA disease, neither overall survival (HR, 0.87; 95% CI, 0.34-2.27; p [ 0.783) nor recurrence-free survival (HR, 0.79; 95% CI, 0.38-1.65; p [ 0.534) was significantly different when compared between patients receiving ACT and those who did not. Similar results were also achieved after propensity score matching.Conclusions. The data presented herein demonstrated that ACT might provide survival benefits for squamous lung cancer patients with p-stage IB disease.

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

“…A total of 5 studies [ 8 , 9 , 13 – 15 ] provided 4 years of OS data for the participants, the test for heterogeneity showed statistical heterogeneity between studies ( P = .002, I 2 = 76%).Analysis using a random effects model showed that postoperative adjuvant chemotherapy improved the 4-year survival of patients compared with postoperative observational follow-up (OR = 1.52, 95% CI 1.05–2.18, P = .03). See Figure 3 .…”

“…A total of 5 of the 11 included studies [ 9 , 11 , 13 , 15 , 19 ] provided DFS or RFS data for the participant, heterogeneity test showed statistical heterogeneity among studies ( P = .12, I 2 = 46%).Analysis using random effects model showed that adjuvant chemotherapy prolonged DFS and RFS in NSCLC patients compared with postoperative observation (OR = 1.57, 95% CI 1.3–1.9, P < .00001). See Figure 5 .…”

“…[18] Adjuvant chemotherapy is highly responsive in poorly differentiated patients older than 65 years of age [14,17,18] and it is controversial whether different pathologic types are associated with the efficacy of postoperative adjuvant chemotherapy. [10,13,17] Buhl et al have found that molecular profiles of NSCLC tissues are predictive of the efficacy of postoperative adjuvant chemotherapy, [26] in addition to this, Lin et al found that TP53 mutations were significantly associated with tumor progression and suggested that TP53 mutations may be one of the biomarkers of whether or not to receive adjuvant chemotherapy postoperatively. [27] A total of 13 studies were included in this paper after selecting the reference according to the inclusion and exclusion criteria, and Meta-analysis showed that postoperative adjuvant chemotherapy for stage IB NSCLC significantly improves patients' overall survival, disease-free survival, and recurrencefree survival compared with surgical treatment alone, and is definitively beneficial in terms of improvement in near-term prognosis.…”

“…A total of 5 studies [8,9,[13][14][15] provided 8 years of OS data for the participants, the results of the heterogeneity test showed statistical heterogeneity among the studies (P = .04, I 2 = 60%). Analysis using the random effects model showed that the difference in OS at 8 years between the adjuvant chemotherapy and postoperative observation groups was not statistically significant, statistically speaking, postoperative adjuvant chemotherapy did not significantly improve the 8-year survival rate of NSCLC patients (OR = 1.5, 95% CI 0.94-2.4, P = .09), but the positive impact of adjuvant chemotherapy on the improvement of patients' longterm survival rate was undeniable.…”

“…Twelve of the 13 included studies [7][8][9][10][11][12][13][14][15][16][17][18] provided data related to the median OS of the participants. The test for heterogeneity showed no statistical heterogeneity between studies (P = .34, I 2 = 11%) and was analyzed using a fixed effects model.…”