Bayesian network meta-comparison of maintenance treatments for stage IIIb/IV non-small-cell lung cancer (NSCLC) patients with good performance status not progressing after first-line induction chemotherapy: results by performance status, EGFR mutation, histology and response to previous induction

When Should Spinal Surgery Be Considered for Spinal Metastasis from Non-Small Cell Lung Cancer?-Propensity Score Matched Study between Surgery with Radiotherapy and Radiotherapy Alone

(1) Background: Although metastatic spine disease is increasing, the debate on therapeutic modality remains due to the heterogeneity of tumors and patients. This study aims to evaluate the efficacies of surgery and risk factors for patients' survival from potentially unstable spinal metastasis of non-small cell lung cancer; (2) Methods: Twenty-two patients undergoing surgery and radiotherapy (group I) were compared with 22 patients undergoing radiotherapy alone (group II) using propensity score matching in a 1-to-1 format. Clinical outcomes included the performance status and ambulatory status. In addition, independent risk factors for patients' survival were evaluated, including the molecular targeted therapy for mutations; (3) Results: deterioration in neurologic status was only observed in group II compared to group I (22.7% vs. 0%, p-value = 0.018). In addition, five patients in the surgery group showed improved Frankel grades. Regarding the patients' survival, a smoking history of more than ten pack-years (hazard ratio (HR) = 12.18), worse performance status (HR = 6.86), and absence of mutations (HR = 3.39) were the independent risk factors; (4) Conclusions: Spinal surgery with radiotherapy could have advantages for improving the neurologic status including ambulation for potentially unstable spine due to metastasis. Thus, surgery should be considered for patients with a longer life expectancy resulting from better performance status and use of the targeted therapy.

Clinical benefit of pembrolizumab in treatment of first line non-small cell lung cancer: a systematic review and meta-analysis of clinical characteristics

OBJECTIVE

Pembrolizumab has become an integral first line therapeutic agent for non-small cell lung cancer (NSCLC), but its potential predictive role in clinical and molecular characteristics remains to be clarified. Accordingly, we performed a systematic review and meta-analysis to evaluate the clinical benefit of pembrolizumab in treatment of first line NSCLC and to select individuals with the greatest potential benefit from pembrolizumab therapy, in order to obtain a more accurate treatment of NSCLC in immunotherapy.

METHODS

Mainstream oncology datasets and conferences were searched for randomized clinical trials (RCTs) published before August 2022. RCTs involved individuals with first line NSCLC treated with pembrolizumab monotherapy or in combination with chemotherapy. Two authors independently selected the studies, extracted data, and assessed the risk of bias. The basic characteristics of the included studies were recorded, along with 95 percent confidence intervals (CI) and hazard ratios (HR) for all patients and subgroups. The primary endpoint was overall survival (OS), and secondary endpoints was progression-free survival (PFS). Pooled treatment data were estimated using the inverse variance-weighted method.

RESULTS

Five RCTs involving 2,877 individuals were included in the study. Pembrolizumab-based therapy significantly improved OS (HR 0.66; CI 95%, 0.55-0.79; p < 0.00001) and PFS (HR 0.60; CI 95%, 0.40-0.91; p = 0.02) compared with chemotherapy. OS was substantially enhanced in individuals aged < 65 years (HR 0.59; CI 95%, 0.42-0.82; p = 0.002), males (HR 0.74; CI 95%, 0.65-0.83; p < 0.00001), with a smoking history (HR 0.65; CI 95%, 0.52-0.82; p = 0.0003), with PD-L1 tumor proportion score (TPS) < 1% (HR 0.55; CI 95%, 0.41-0.73; p < 0.0001) and TPS ≥ 50% (HR 0.66; CI 95%, 0.56-0.76; p < 0.00001), but not in individuals aged ≥ 75 years (HR 0.82; CI 95%, 0.56-1.21; p = 0.32), females (HR 0.57; CI 95%, 0.31-1.06; p = 0.08), never smokers (HR 0.57; CI 95%, 0.18-1.80; p = 0.34), or with TPS 1-49% (HR 0.72; CI 95%, 0.52-1.01; p = 0.06). Pembrolizumab significantly prolonged OS in NSCLC patients, regardless of histology type (squamous or non-squamous NSCLC), performance status (PS) (0 or 1), and brain metastatic status (all p < 0.05). Subgroup analysis revealed that pembrolizumab combined with chemotherapy had more favorable HR values than pembrolizumab monotherapy in improving the OS of individuals with different clinical and molecular features.

CONCLUSION

Pembrolizumab-based therapy is a valuable option for first line treating advanced or metastatic NSCLC. Age, sex, smoking history and PD-L1 expression status can be used to predict the clinical benefit of pembrolizumab. Cautiousness was needed when using pembrolizumab in NSCLC patients aged ≥ 75 years, females, never smokers, or in patients with TPS 1-49%. Furthermore, pembrolizumab in combination with chemotherapy may be a more effective treatment regimen.

LncRNA NORAD accelerates the progression of non-small cell lung cancer via targeting miRNA-455/CDK14 axis

BACKGROUND

To explore the potential involvement of long non-coding RNA (lncRNA) NORAD in regulating the progression of Non-small cell lung cancer (NSCLC), and its possible mechanism.

METHODS

Relative level of NORAD in NSCLC tissues and cell lines was determined. Its level in NSCLC patients with different tumor staging (T1-T2, T3-T4) and either with lymphatic metastasis or not was examined as well. Kaplan-Meier curves were depicted for assessing the prognostic value of NORAD in NSCLC. Regulatory effects of NORAD on the proliferative ability of NCI-H1650 and HCC827 cells were evaluated. Dual-luciferase reporter gene assay was conducted to identify the binding between NORAD and miRNA-455, as well as between miRNA-455 and CDK14. At last, the role of NORAD/miRNA-455/CDK14 regulatory loop in influencing the progression of NSCLC was determined.

RESULTS

NORAD was upregulated in NSCLC tissues and cells. Its level was higher in NSCLC patients with advanced stage or accompanied with lymphatic metastasis. Worse prognosis was observed in NSCLC patients presenting high level of NORAD. Silence of NORAD attenuated the proliferative ability of NCI-H1650 and HCC827 cells. MiRNA-455 was the downstream target binding to NORAD. Its level was negatively regulated by NORAD. Knockdown of miRNA-455 could reverse the role of NORAD in regulating the proliferative ability of NSCLC. Moreover, CDK14 was the target gene of miRNA-455. CDK14 level was negatively regulated by miRNA-455.

CONCLUSIONS

LncRNA NORAD is upregulated in NSCLC, which enhances the proliferative ability of tumor cells by targeting miRNA-455/CDK14 axis and thereby accelerates the progression of NSCLC.

Measuring the indirect cost associated with advanced non-small cell lung cancer: a nationwide cross-sectional study in China

PURPOSE

This study was conducted to estimate the indirect cost of locally advanced and metastatic non-small cell lung cancer (NSCLC) without sensitizing EGFR and ALK alterations in China and explore the predictors from both patient and caregiver perspectives.

METHODS

Data were obtained from a nationwide cross-sectional study for the patients with advanced NSCLC (stage IIIB-IV) and their caregivers. Indirect medical cost was estimated as health productivity loss based on self-reported income and loss of work time. The generalized linear model was used to assess the independent associations between statistically significant variables and indirect economic burden.

RESULTS

611 pairs of patients and patient caregivers from 13 medical centers in five provinces in China participated in this investigation. The indirect medical cost associated with advanced NSCLC since the patient diagnosed was $1413 per capita in China. General linear regression results showed that the indirect medical cost was significantly influenced by duration of disease since diagnosis, treatment options, caregivers' occupation and age (P < 0.05).

CONCLUSION

The indirect economic burden linked to advanced NSCLC in China is considerable on patients, and their caregivers. To minimize the severe challenges of indirect economic burden related to advanced NSCLC, expanding the coverage of the medical insurance and assistance system to reimburse part of the indirect costs related to cancer, as well as strengthening the accessibility for more effective therapies to improve the prognosis of advanced NSCLC, and further promote the patients and their caregivers to return to work or normal life may be the potentially feasible approaches.

Retrospective observational cohort study on innovation in oncology and progress in survival: How far have we gotten in the two decades of treating patients with advanced non-small cell lung cancer as a single population?

We assessed the impact of new antineoplastic agents on the overall survival (OS) of advanced non-small cell lung cancer (aNSCLC) patients followed up until 2012. Multivariate regression models were run for OS (outcome) and four proxies for innovation (exposure): Index (InnovInd, for SEER-Research data 1973–2012) and three levels of aggregation of Mean Medication Vintage, i.e. Overall (MMV_Overall), using data aggregated at the State Level (MMV_State), and using patient-level data (MMV_Patient) using data from the US captured in SEER-Medicare 1991–2012. We derived Hazard ratios (HR) from Royston-Parmar models and odds ratios (OR) from a logistic regression on 1-year OS. Including 164,704 patients (median age 72 years, 56.8% stage IV, 61.8% with no comorbidities, 37.8% with adenocarcinoma, 22.9% with squamous-cell, 6.1% were censored). One-year OS improved from 0.22 in 1973 to 0.39 in 2012, in correlation with InnovInd (r = 0.97). Ten new NSCLC drugs were approved and 28 more used off-label. Regression-models results indicate that therapeutic innovation only marginally reduced the risk of dying (HROverall = 0.98 [0.98–0.98], HR_MMV-Patient = 0.98 [0.97–0.98], and HR_MMV-State = 0.98 [0.98–0.98], and slightly improved 1-year survival (OR_MMV-Overall = 1.05 95%CI [1.04–1.05]). These results were validated with data from the Swedish National Health Data registers. Until 2013, aNSCLC patients were treated undifferentiated and the introduction of innovative therapies had statistically significant, albeit modest, effects on survival. Most treatments used off-guidelines highlight the high unmet need; however new advancements in treatment may further improve survival.

lncRNA ZEB2-AS1 Aggravates Progression of Non-Small Cell Lung Carcinoma via Suppressing PTEN Level

Background

The aim of this study was to assess the involvement of lncRNA ZEB2-AS1 in the development of NSCLC and to explore the potential mechanism involved.

Material/Methods

ZEB2-AS1 expressions in 48 paired NSCLC tissues and paracancerous tissues were examined by qRT-PCR. ZEB2-AS1 level in NSCLC patients affected by tumor staging and lymphatic metastasis was examined as well. Regulatory effects of ZEB2-AS1 on proliferative, migratory, and invasive properties of NCI-H1650 and HCC827 cells were evaluated. The interaction between ZEB2-AS1 and EZH2 was identified through RIP assay. Subsequently, the binding of EZH2 on PTEN promoter region was tested by ChIP. Finally, rescue experiments were conducted to assess the involvement of PTEN in the development of NSCLC.

Results

ZEB2-AS1 was upregulated in NSCLC tissues and cell lines. Its level was higher in NSCLC patients with T3–T4 or accompanied with lymphatic metastasis relative to those with T1–T2 or without metastatic loci. Knockdown of ZEB2-AS1 suppressed proliferative, migratory, and invasive properties of NCI-H1650 and HCC827 cells. PTEN level was elevated after knockdown of ZEB2-AS1 or EZH2 in HCC827 cells. Subsequently, RIP assay proved the interaction between ZEB2-AS1 and EZH2. Knockdown of ZEB2-AS1 markedly reduced the binding of EZH2 on the PTEN promoter region. Notably, knockdown of PTEN reversed the effects of EZB2-AS1 on regulating proliferative, migratory, and invasive properties of NSCLC cells.

Conclusions

lncRNA ZEB2-AS1 is upregulated in NSCLC, which elevates the viability and malignant degree of NSCLC cells by downregulating PTEN, thus aggravating the progression of NSCLC.

Relative efficacy of interventions in the treatment of second-line non-small cell lung cancer: a systematic review and network meta-analysis

BACKGROUND

Locally advanced or metastatic non-small cell lung cancer (NSCLC) that has progressed after first-line treatment has a poor prognosis. Recent randomized clinical trials (RCTs) have demonstrated survival benefits of alternative treatments to docetaxel. However, information is lacking on which patients benefit the most and what drug or regimen is optimal. We report a systematic review and network meta-analysis (NMA) of second-line treatments in all subgroup combinations determined by histology, programmed death ligand 1 (PD-L1) expression, and epidermal growth factor receptor (EGFR) mutation.

METHODS

MEDLINE, PubMed, EMBASE, Biosciences Information Service (using the Dialog Platform), Cochrane Library, and abstracts from scientific meetings were searched for RCTs published up to September 2015. Key outcomes were overall survival (OS) and progression-free survival (PFS). Bayesian hierarchical exchangeable NMAs were conducted to calculate mean survival times and relative differences for eight subgroups, using docetaxel as the reference comparator. For OS, the NMA was based on hazard ratios applied to a first-order fractional polynomial model fitted to the reference treatment. For PFS, a second-order fractional polynomial model was fitted to reconstructed patient-level data for the entire network of evidence.

RESULTS

The search identified 30 studies containing 17 different treatment regimens. Docetaxel plus ramucirumab was associated with a significant improvement in OS and PFS, relative to docetaxel, regardless of patient type. Docetaxel plus nintedanib showed similar efficacy to docetaxel plus ramucirumab in the nonsquamous populations. EGFR tyrosine kinase inhibitors (TKIs) erlotinib and gefitinib showed superior levels of efficacy in EGFR mutation-positive populations and the one PD-1 immunotherapy (nivolumab) studied showed superior efficacy in the populations exhibiting high PD-L1 expression.

CONCLUSIONS

In the absence of head-to-head comparisons, we performed a mixed-treatment analysis to synthesize evidence of the efficacy of each treatment. Benefits are optimized by targeting specific treatments to individual patients guided by histology, PD-L1 expression, and EGFR mutation status.

SYSTEMATIC REVIEW REGISTRATION

This review is registered in PROSPERO (registration number: CRD42014013780 available at www.crd.york.ac.uk/PROSPERO ).

Patient performance status and cancer immunotherapy efficacy: a meta-analysis

Immune checkpoint inhibitors (CKIs) are therapeutic weapons in several advanced malignancies. Performance status is a validated prognostic variable in cancer patients; it possibly affects the efficiency of the immune system. We performed a systematic review and meta-analysis to investigate the predictive role of PS toward treatment with CKIs in cancer patients. Following PRISMA guidelines, an electronic search from PubMed, The Cochrane Library and Embase was performed, from the inception of each database to May 31, 2018. Inclusion criteria were (1) randomized trials comparing CKI with standard therapy for the treatment of patients with solid tumors; (2) information on overall survival (OS) according to PS; (3) full text available; and (4) reported in English language. Data were pooled using HRs for OS according to random effect model. The effect of experimental versus control arms was evaluated in PS = 0 and 1-2 subgroups, and the heterogeneity between the two estimates was assessed using an interaction test. The OS differences between PS = 0 and PS = 1-2 strata were evaluated in all studies and according to predefined subgroups. Eighteen studies were eligible, with 11,354 patients [PS = 0 group 5217 patients (46%); PS = 1-2 group 6137 patients (54%)]. The pooled HR for OS was 0.78 (95% CI 0.69-0.89) in PS = 0 patients. In PS = 1-2 patients, the pooled OS HR was 0.78 (95% CI 0.71-0.86). The OS difference between PS = 0 and PS = 1-2 patients treated with CKI was not significant (P = 0.99). CKI improves survival irrespective of patients' PS. PS should not guide treatment choice for anticancer immunotherapy.

Erlotinib in routine clinical practice for first-line maintenance therapy in patients with advanced non-small cell lung cancer (NSCLC)

PURPOSE

The controlled phase III trial SATURN demonstrated that maintenance therapy with erlotinib after the first-line platinum-based chemotherapy prolonged progression-free survival (PFS) and overall survival (OS) of non-small cell lung cancer (NSCLC) patients with advanced, non-progressive disease. We conducted the non-interventional study SATURN NIS to investigate the effectiveness and tolerability of erlotinib maintenance in daily clinical practice.

METHODS

This single-arm NIS screened 290 patients with locally advanced or metastatic NSCLC (stage IIIB or IV) and stable disease after standard platinum-based first-line chemotherapy in 95 institutions across Germany. Erlotinib was dosed and administered corresponding to the terms of the marketing authorization at the time of recruitment. The main effectiveness endpoint was subjects' OS at 1 year. Subgroup analyses of survival estimates of OS and PFS were performed.

RESULTS

272 patients were eligible for analysis (median age 66 years, 37.1% females, 99.6% Caucasian, median ECOG performance status 1, 61.8% adenocarcinoma, 96.3% of patients with stable disease). Maintenance therapy with erlotinib resulted in median OS comparable to that of the SATURN phase III trial 10.4 months [95% CI: (8.8; 12.5) vs. 11.9 months]. The 1-year survival rate was 45.6% [95% CI: (37.5%; 53.6%)]. No new safety signals were observed. As expected, patients with epidermal growth factor receptor (EGFR) mutations derived a greater benefit concerning OS and PFS than EGFR-wild-type patients. Moreover, a significant association of OS and PFS and the smoking status was observed.

CONCLUSIONS

The results of this non-interventional study support the current clinical practice of erlotinib switch maintenance in EGFR-mutation-positive patients.

Meta-analysis of first-line therapies with maintenance regimens for advanced non-small-cell lung cancer (NSCLC) in molecularly and clinically selected populations

Evidence has suggested survival benefits of maintenance for advanced NSCLC patients not progressing after first‐line chemotherapy. Additionally, particular first‐line targeted therapies have shown survival improvements in selected populations. Optimal first‐line and maintenance therapies remain unclear. Here, currently available evidence was synthesized to elucidate optimal first‐line and maintenance therapy within patient groups. Literature was searched for randomized trials evaluating first‐line and maintenance regimens in advanced NSCLC patients. Bayesian network meta‐analysis was performed within molecularly and clinically selected groups. The primary outcome was combined clinically meaningful OS and PFS benefits. A total of 87 records on 56 trials evaluating first‐line treatments with maintenance were included. Results showed combined clinically meaningful OS and PFS benefits with particular first‐line with maintenance treatments, (1) first‐line intercalated chemotherapy+erlotinib, maintenance erlotinib in patients with EGFR mutations, (2) first‐line afatinib, maintenance afatinib in patients with EGFR deletion 19, (3) first‐line chemotherapy + bevacizumab, maintenance bevacizumab in EGFR wild‐type patients, (4) chemotherapy+conatumumab, maintenance conatumumab in patients with squamous histology, (5) chemotherapy+cetuximab, maintenance cetuximab or chemotherapy + necitumumab, maintenance necitumumab in EGFR FISH‐positive patients with squamous histology, and (6) first‐line chemotherapy+bevacizumab, maintenance bevacizumab or first‐line sequential chemotherapy+gefitinib, maintenance gefitinib in patients clinically enriched for EGFR mutations with nonsquamous histology. No treatment showed combined clinically meaningful OS and PFS benefits in patients with EGFR L858R or nonsquamous histology. Particular first‐line with maintenance treatments show meaningful OS and PFS benefits in patients selected by EGFR mutation or histology. Further research is needed to achieve effective therapy for patients with EGFR mutation L858R or nonsquamous histology.

Pembrolizumab versus Chemotherapy for PD-L1-Positive Non-Small-Cell Lung Cancer

BACKGROUND

Pembrolizumab is a humanized monoclonal antibody against programmed death 1 (PD-1) that has antitumor activity in advanced non-small-cell lung cancer (NSCLC), with increased activity in tumors that express programmed death ligand 1 (PD-L1).

METHODS

In this open-label, phase 3 trial, we randomly assigned 305 patients who had previously untreated advanced NSCLC with PD-L1 expression on at least 50% of tumor cells and no sensitizing mutation of the epidermal growth factor receptor gene or translocation of the anaplastic lymphoma kinase gene to receive either pembrolizumab (at a fixed dose of 200 mg every 3 weeks) or the investigator's choice of platinum-based chemotherapy. Crossover from the chemotherapy group to the pembrolizumab group was permitted in the event of disease progression. The primary end point, progression-free survival, was assessed by means of blinded, independent, central radiologic review. Secondary end points were overall survival, objective response rate, and safety.

RESULTS

Median progression-free survival was 10.3 months (95% confidence interval [CI], 6.7 to not reached) in the pembrolizumab group versus 6.0 months (95% CI, 4.2 to 6.2) in the chemotherapy group (hazard ratio for disease progression or death, 0.50; 95% CI, 0.37 to 0.68; P<0.001). The estimated rate of overall survival at 6 months was 80.2% in the pembrolizumab group versus 72.4% in the chemotherapy group (hazard ratio for death, 0.60; 95% CI, 0.41 to 0.89; P=0.005). The response rate was higher in the pembrolizumab group than in the chemotherapy group (44.8% vs. 27.8%), the median duration of response was longer (not reached [range, 1.9+ to 14.5+ months] vs. 6.3 months [range, 2.1+ to 12.6+]), and treatment-related adverse events of any grade were less frequent (occurring in 73.4% vs. 90.0% of patients), as were grade 3, 4, or 5 treatment-related adverse events (26.6% vs. 53.3%).

CONCLUSIONS

In patients with advanced NSCLC and PD-L1 expression on at least 50% of tumor cells, pembrolizumab was associated with significantly longer progression-free and overall survival and with fewer adverse events than was platinum-based chemotherapy. (Funded by Merck; KEYNOTE-024 ClinicalTrials.gov number, NCT02142738 .).

Anti-Metastatic and Anti-Angiogenic Activities of Core-Shell SiO2@LDH Loaded with Etoposide in Non-Small Cell Lung Cancer

Currently, nanoparticles have gained a great attention in the anti-tumor research area. However, to date, studies on the anti-metastasis action of core-shell SiO2@LDH (LDH: layered double hydroxide) nanoparticles remain untouched. Two emerging aspects considered are establishing research on the controlling delivery effect of SiO2@LDH combined with anti-cancer medicine from a new perspective. The fine properties synthetic SiO2@LDH-VP16 (VP16: etoposide) are practiced to exhibit the nanoparticle's suppression on migration and invasion of non-small cell lung cancer (NSCLC). Both in vitro and in vivo inspection shows that SiO2@LDH can help VP16 better function as an anti-metastasis agent. On the other hand, anti-angiogenic efficiency, co-localization, as well as western blot are investigated to explain the possible mechanism. A clear mergence of SiO2@LDH-VP16 and cytomembrane/microtubule may be observed from co-location images. Results offer evidence that SiO2@LDH-VP16 plays positions on cytomembrane and microtubules. It efficiently inhibits metastasis on NSCLC by reducing vascularization, and eliciting depression of the PI3K-AKT and FAK-Paxillin signaling pathways. SiO2@LDH-VP16, the overall particle morphology, and function on anti-metastasis and anti-angiogenic may be tuned to give new opportunities for novel strategies for cancer therapy.

Single-agent maintenance therapy for advanced non-small cell lung cancer (NSCLC): a systematic review and Bayesian network meta-analysis of 26 randomized controlled trials

Background

The benefit of maintenance therapy has been confirmed in patients with non-progressing non-small cell lung cancer (NSCLC) after first-line therapy by many trials and meta-analyses. However, since few head-to-head trials between different regimens have been reported, clinicians still have little guidance on how to select the most efficacious single-agent regimen. Hence, we present a network meta-analysis to assess the comparative treatment efficacy of several single-agent maintenance therapy regimens for stage III/IV NSCLC.

Methods

A comprehensive literature search of public databases and conference proceedings was performed. Randomized clinical trials (RCTs) meeting the eligible criteria were integrated into a Bayesian network meta-analysis. The primary outcome was overall survival (OS) and the secondary outcome was progression free survival (PFS).

Results

A total of 26 trials covering 7,839 patients were identified, of which 24 trials were included in the OS analysis, while 23 trials were included in the PFS analysis. Switch-racotumomab-alum vaccine and switch-pemetrexed were identified as the most efficacious regimens based on OS (HR, 0.64; 95% CrI, 0.45–0.92) and PFS (HR, 0.54; 95% CrI, 0.26–1.04) separately. According to the rank order based on OS, switch-racotumomab-alum vaccine had the highest probability as the most effective regimen (52%), while switch-pemetrexed ranked first (34%) based on PFS.

Conclusions

Several single-agent maintenance therapy regimens can prolong OS and PFS for stage III/IV NSCLC. Switch-racotumomab-alum vaccine maintenance therapy may be the most optimal regimen, but should be confirmed by additional evidence.

Comparison of the efficacy and tolerability of gefitinib with pemetrexed maintenance after first-line platinum-based doublet chemotherapy in advanced lung adenocarcinoma: single-center experience

Purpose

Both gefitinib and pemetrexed maintenance were effective therapies for advanced lung adenocarcinoma, but which is better is unclear. For patients with advanced lung adenocarcinoma, we have no idea whether we should choose gefitinib or pemetrexed maintenance in clinical practice. Here, we assessed the efficacy and tolerability of gefitinib versus pemetrexed maintenance in these patients.

Patients and methods

A total of 101 patients were identified and divided into gefitinib (n=53) or pemetrexed (n=48) maintenance. Epidermal growth factor receptor (EGFR) status of tumors was analyzed in 67 patients. Disease control rate (DCR), progression-free survival (PFS), and overall survival (OS) were compared between the two groups.

Results

The results showed that DCR (79.2% vs 75%, P=0.642) was similar between gefitinib and pemetrexed groups. The PFS of gefitinib was significantly longer than that of pemetrexed (8 months vs 5.4 months, hazard ratio [HR]: 0.520, 95% confidence interval [CI]: 0.341–0.791, P=0.002); however, the OS was similar (19.9 months vs 18.8 months, HR: 1.006, 95% CI: 0.664–1.525, P=0.977). In EGFR mutation-positive patients, PFS was significantly longer in gefitinib (12 months vs 5.4 months; HR: 0.158, 95% CI: 0.074–0.333, P<0.001), whereas in EGFR wild-type subgroup gefitinib had a significantly shorter PFS than that by pemetrexed (2.5 months vs 5 months; HR: 2.822, 95% CI: 1.137–7.005, P=0.025). Cox multivariate regression analysis of PFS for overall population showed that smoking status (P=0.001) and maintenance regimens (P=0.013) were independent prognostic factors for PFS. Both gefitinib and pemetrexed were well tolerated.

Conclusion

Gefitinib compared with pemetrexed as maintenance therapy had a significantly longer PFS and a similar OS with good tolerability in patients with advanced lung adenocarcinoma. Moreover, for EGFR mutation-positive patients, gefitinib maintenance had a significantly longer PFS; however, pemetrexed maintenance was considered more effective for EGFR wild-type patients.