Association of Molecular Profiles and Mutational Status With Distinct Histological Lung Adenocarcinoma Subtypes. An Analysis of the LACE-Bio Data

BACKGROUND

Adjuvant chemotherapy (AC) is indicated for stage II and stage III lung adenocarcinomas (ADC). Using the LACE Bio II database, we analyzed the distribution of various mutations across the subtypes of ADCs and studied the prognostic and predictive roles of PD-L1, TMB, and Tumor Infiltrating Lymphocytes (TILs).

MATERIALS AND METHODS

Clinical and genomic data from the LACE Bio II data were extracted. Patients were divided into ADC subtypes, in which the grouping was done based on their known clinical behavior (Lepidic [LEP], Acinar/Papillary [ACI or PAP], Micropapillary/Solid [MIP or SOL], Mucinous [MUC] and Others). Kaplan-Meier (KM) and log-rank test were used to compare survival based on PD-L1, TMB, TILs and combinations of TMB with PD-L1 and TILs. Adjusted Hazard Ratios (HR) were analyzed with Overall Survival (OS), Disease-Free Survival (DFS) and Lung Cancer-Specific Survival (LCSS) as endpoints.

RESULTS

A total of 375 ADC patients were identified. MIP/SOL was the subtype most commonly positive for various biomarkers. PD-L1 Negative/high TMB was associated with better outcomes in terms of OS (HR = 0.46 [0.23-0.89], P = .021) and DFS (HR = 0.52 [0.30-0.90], P = .02), relative to PD-L1 Negative/low TMB. High TMB predicted worse outcome with AC use in terms of OS (ratio of hazard ratio rHR = 2.75 [1.07-7.04], P = .035). Marked TILs had better outcome with AC for DFS (rHR = 0.22 [0.06-0.87], P = .031 and LCSS (rHR = 0.08 [0.01-0.66], P = .019) respectively. There was also a beneficial effect of AC among patients with Marked TILs/low TMB in terms of DFS (rHR = 0.06 [0.01-0.53], P = .011).

CONCLUSION

High TMB has a prognostic role in resectable lung ADC. The high TMB group had a poor outcome with AC, suggesting that this group may be better served with immune checkpoint therapy.

Prognostic and predictive effect of KRAS gene copy number and mutation status in early stage non-small cell lung cancer patients

Background

In the current analysis, we characterize the prognostic significance of KRAS mutations with concomitant copy number aberrations (CNA) in early stage non-small cell lung cancer (NSCLC), and evaluate the ability to predict survival benefit from adjuvant chemotherapy.

Methods

Clinical and genomic data from the LACE (Lung Adjuvant Cisplatin Evaluation)-Bio consortium was utilized. CNAs were categorized as Gain (CN ≥2) or Neutral (Neut)/Loss; KRAS status was defined as wild type (WT) or mutant (MUT). The following groups were compared in all patients and the adenocarcinoma subgroup, and were correlated to survival endpoints using a Cox proportional hazards model: WT + Neut/Loss (reference), WT + Gain, MUT + Gain and MUT + Neut/Loss. A treatment-by-variable interaction was added to evaluate predictive effect.

Results

Of the 946 (399 adenocarcinoma) NSCLC patients, 41 [30] had MUT + Gain, 145 [99] MUT + Neut/Loss, 125 [16] WT + Gain, and 635 [254] WT + Neut/Loss. A non-significant trend towards worse lung cancer-specific survival (LCSS; HR =1.34; 95% CI, 0.83-2.17, P=0.232), DFS (HR =1.34; 95% CI, 0.86-2.09, P=0.202) and OS (HR =1.59; 95% CI, 0.99-2.54, P=0.055) was seen in KRAS MUT + Gain patients relative to KRAS WT + Neut/Loss patients. A negative prognostic effect of KRAS MUT + Neut/Loss was observed for LCSS (HR =1.32; 95% CI, 1.01-1.71, P=0.038) relative to KRAS WT + Neut/Loss on univariable analysis, but to a lesser extent after adjusting for covariates (HR =1.28; 95% CI, 0.97-1.68, P=0.078). KRAS MUT + Gain was associated with a greater beneficial effect of chemotherapy on DFS compared to KRAS WT + Neut/Loss patients (rHR =0.33; 95% CI, 0.11-0.99, P=0.048), with a non-significant trend also seen for LCSS (rHR =0.41; 95% CI, 0.13-1.33, P=0.138) and OS (rHR =0.40; 95% CI, 0.13-1.26, P=0.116) in the adenocarcinoma subgroup.

Conclusions

A small prognostic effect of KRAS mutation was identified for LCSS, and a trend towards worse LCSS, DFS and OS was noted for KRAS MUT + Gain. A potential predictive effect of concomitant KRAS mutation and copy number gain was observed for DFS in adenocarcinoma patients. These results could be driven by the small number of patients and require validation.

Randomized Study of Maintenance Pemetrexed Versus Observation for Treatment of Malignant Pleural Mesothelioma: CALGB 30901

BACKGROUND

The role of maintenance therapy for malignant pleural mesothelioma (MPM) is unknown. We performed a randomized phase II trial to determine if continuation of pemetrexed after first-line pemetrexed and platinum would improve progression-free survival (PFS).

PATIENTS AND METHODS

Eligible patients with unresectable MPM, without disease progression following 4 to 6 cycles of pemetrexed and platinum were randomized 1:1 to observation or continuation of pemetrexed until progression, stratified by number of cycles (< 6 or 6), cis- or carboplatin containing regimen, and histology. Study size was calculated based on the assumption that observation would produce a median PFS of 3 months and pemetrexed would yield median PFS of 6 months.

RESULTS

A total of 72 patients were registered from December 2010 to June 2016. The study closed early after 53 patients were randomized; 49 eligible (22 on the observation arm and 27 on the pemetrexed arm) were included in the analysis. The median PFS was 3 months (95% confidence interval [CI], 2.6-11.9 months) on observation and 3.4 months (95% CI, 2.8-9.8 months) on pemetrexed (hazard ratio [HR], 0.99; 95% CI, 0.51-1.90; P = .9733). The median overall survival (OS) was 11.8 months (95% CI, 9.3-28.7 months) for observation, and 16.3 months (95% CI, 10.5-26.0 months) for pemetrexed (HR, 0.86; 95% CI, 0.44-1.71; P = .6737). Grade 3 or 4 toxicities on the pemetrexed arm included anemia (8%), lymphopenia (8%), neutropenia (4%), and fatigue (4%). A higher baseline level of soluble mesothelin-related peptide was associated with worse PFS (HR, 1.86; 95% CI, 1.00-3.46; P = .049).

CONCLUSION

Maintenance pemetrexed following initial pemetrexed and platinum chemotherapy does not improve PFS in patients with MPM.

Evidence That Established Lung Cancer Mortality Disparities in American Indians Are Not Due to Lung Cancer Genetic Testing and Targeted Therapy Disparities

BACKGROUND

American Indians and Alaska Natives (AI/AN) continue to experience extreme lung cancer health disparities. The state of Minnesota is home to over 70,000 AI/AN, and this population has a 2-fold increase in lung cancer mortality compared to other races within Minnesota. Genetic mutation testing in lung cancer is now a standard of high-quality lung cancer care, and EGFR mutation testing has been recommended for all adenocarcinoma lung cases, regardless of smoking status. However, genetic testing is a controversial topic for some AI/AN.

PATIENTS AND METHODS

We performed a multisite retrospective chart review funded by the Minnesota Precision Medicine Grand Challenge as a demonstration project to examine lung cancer health disparities in AI/AN. We sought to measure epidemiology of lung cancer among AI receiving diagnosis or treatment in Minnesota cancer referral centers as well as rate of EGFR testing. The primary outcome was the rate of EGFR mutational analysis testing among cases and controls with nonsquamous, non-small-cell lung cancer. We secured collaborations with 5 health care systems covering a diverse geographic and demographic population.

RESULTS

We identified 200 cases and 164 matched controls from these sites. Controls were matched on histology, smoking status, sex, and age. In both groups, about one third of subjects with adenocarcinoma received genetic mutation testing.

CONCLUSION

There was no significant difference in mutation testing in AI compared to non-AI controls at large health care systems in Minnesota. These data indicate that other factors are likely contributing to the higher mortality in this group.

Smoking, Sex, and Non-Small Cell Lung Cancer: Steroid Hormone Receptors in Tumor Tissue (S0424)

Background

To what extent steroid hormones contribute to lung cancer in male and female never smokers and smokers is unclear. We examined expression of hormone receptors in lung tumors by sex and smoking.

Methods

Patients with primary non-small cell lung cancer were recruited into an Intergroup study in the United States and Canada, led by SWOG (S0424). Tumors from 813 cases (450 women and 363 men) were assayed using immunohistochemistry for estrogen receptor (ER)-α, ER-β, progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2). Linear regression was used to examine differences in expression by sex and smoking status. Cox proportional hazard models were used to estimate survival associated with the receptors. All statistical tests were two-sided.

Results

In ever smokers, postmenopause and oral contraceptive use were associated with lower nuclear ER-β (P = .02) and total (nuclear + cytoplasmic) PR expression (P = .02), respectively. Women had lower cytoplasmic ER-α (regression coefficient [β], or differences in H-scores = -15.8, P = .003) and nuclear ER-β (β = -12.8, P = .04) expression than men, adjusting for age, race, and smoking. Ever smokers had both higher cytoplasmic ER-α (β = 45.0, P < .001) and ER-β (β = 25.9, P < .001) but lower total PR (β = -42.1, P < .001) than never smokers. Higher cytoplasmic ER-α and ER-β were associated with worse survival (hazard ratio = 1.73, 95% confidence interval [CI] = 1.15 to 2.58, and HR = 1.59, 95% CI = 1.08 to 2.33, respectively; quartiles 4 vs 1).

Conclusions

Lower expression of nuclear ER-β in women supports the estrogen hypothesis in lung cancer etiology. Increasing cytoplasmic ER-α and ER-β and decreasing PR protein expression may be mechanisms whereby smoking disrupts hormone pathways.

Tumor Mutation Burden as a Biomarker in Resected Non-Small-Cell Lung Cancer

PURPOSE

The survival benefit with adjuvant chemotherapy for patients with resected stage II-III non-small-cell lung cancer (NSCLC) is modest. Efforts to develop prognostic or predictive biomarkers in these patients have not yielded clinically useful tests. We report findings from the Lung Adjuvant Cisplatin Evaluation (LACE)-Bio-II study, in which we analyzed next-generation sequencing and long-term outcomes data from > 900 patients with early-stage NSCLC treated prospectively in adjuvant landmark clinical trials. We used a targeted gene panel to assess the prognostic and predictive effect of mutations in individual genes, DNA repair pathways, and tumor mutation burden (TMB).

METHODS

A total of 908 unmatched, formalin-fixed, paraffin-embedded, resected lung cancer tumor specimens were sequenced using a targeted panel of 1,538 genes. Stringent filtering criteria were applied to exclude germline variants and artifacts related to formalin fixation. Disease-free survival, overall survival, and lung cancer-specific survival (LCSS) were assessed in Cox models stratified by trial and adjusted for treatment, age, sex, performance score, histology, type of surgery, and stage.

RESULTS

Nonsynonymous mutations were identified in 1,515 genes in 908 tumor samples. High nonsynonymous TMB (> 8 mutations/Mb) was prognostic for favorable outcomes (ie, overall survival, disease-free survival, and LCSS) in patients with resected NSCLC. LCSS benefit with adjuvant chemotherapy was more pronounced in patients with low nonsynonymous TMBs (≤ 4 mutations/Mb). Presence of mutations in DNA repair pathways, tumor-infiltrating lymphocytes, TP53 alteration subtype, and intratumor heterogeneity was neither prognostic nor predictive. Statistically significant effect of mutations in individual genes was difficult to determine due to high false-discovery rates.

CONCLUSION

High nonsynonymous TMB was associated with a better prognosis in patients with resected NSCLC. In addition, the benefit of adjuvant chemotherapy on LCSS was more pronounced in patients with low nonsynonymous TMBs. Studies are warranted to confirm these findings.

Genome-wide copy number analyses of samples from LACE-Bio project identify novel prognostic and predictive markers in early stage non-small cell lung cancer

Background

Adjuvant chemotherapy (ACT) provides modest benefit in resected non-small cell lung cancer (NSCLC) patients. Genome-wide studies have identified gene copy number aberrations (CNA), but their prognostic implication is unknown.

Methods

DNA from 1,013 FFPE tumor samples from three pivotal multicenter randomized trials (ACT vs. control) in the LACE-Bio consortium (median follow-up: 5.2 years) was successfully extracted, profiled using a molecular inversion probe SNP assay, normalized relative to a pool of normal tissues and segmented. Minimally recurrent regions were identified. P values were adjusted to control the false discovery rate (Q values).

Results

A total of 976 samples successfully profiled, 414 (42%) adenocarcinoma (ADC), 430 (44%) squamous cell carcinoma (SCC) and 132 (14%) other NSCLC; 710 (73%) males. We identified 431 recurrent regions, with on average 51 gains and 43 losses; 253 regions (59%) were ≤3 Mb. Most frequent gains (up to 48%) were on chr1, 3q, 5p, 6p, 8q, 22q; most frequent losses (up to 40%) on chr3p, 8p, 9p. CNA frequency of 195 regions was significantly different (Q≤0.05) between ADC and SCC. Fourteen regions (7p11-12, 9p21, 18q12, and 19p11-13) were associated with disease-free survival (DFS) (univariate P≤0.005, Q<0.142), with poorer DFS for losses of regions including CDKN2A/B [hazard ratio (HR) for 2-fold lower CN: 1.5 (95% CI: 1.2-1.9), P<0.001, Q=0.020] and STK11 [HR =2.4 (1.3-4.3), P=0.005, Q=0.15]. Chromosomal instability was associated with poorer DFS (HR =1.5, P=0.015), OS (HR =1.2, P=0.189) and lung-cancer specific survival (HR =1.7, P=0.003).

Conclusions

These large-scale genome-wide analyses of gene CNA provide new candidate prognostic markers for stage I-III NSCLC.

Pooled Analysis of the Prognostic and Predictive Effects of TP53 Comutation Status Combined With KRAS or EGFR Mutation in Early-Stage Resected Non-Small-Cell Lung Cancer in Four Trials of Adjuvant Chemotherapy

Purpose Our previous work evaluated individual prognostic and predictive roles of TP53, KRAS, and EGFR in non-small-cell lung cancer (NSCLC). In this analysis, we explore the prognostic and predictive roles of TP53/KRAS and TP53/EGFR comutations in randomized trials of adjuvant chemotherapy versus observation. Patients and Methods Mutation analyses (wild-type [WT] and mutant) for TP53, KRAS, and EGFR were determined in blinded fashion in multiple laboratories. Primary and secondary end points of pooled analysis were overall survival and disease-free survival. We evaluated the role of TP53/KRAS comutation in all patients and in the adenocarcinoma subgroup as well as the TP53/EGFR comutation in adenocarcinoma only through a multivariable Cox proportional hazards model stratified by trial. Results Of 3,533 patients with NSCLC, 1,181 (557 deaths) and 404 (170 deaths) were used for TP53/KRAS and TP53/EGFR analyses. For TP53/KRAS mutation status, no prognostic effect was observed ( P = .61), whereas a borderline predictive effect ( P = .04) was observed with a deleterious effect of chemotherapy with TP53/KRAS comutations versus WT/WT (hazard ratio, 2.49 [95% CI, 1.10 to 5.64]; P = .03). TP53/EGFR comutation in adenocarcinoma was neither prognostic ( P = .83), nor significantly predictive ( P = .86). Similar results were observed for both groups for disease-free survival. Conclusion We could identify no prognostic effect of the KRAS or EGFR driver and TP53 tumor suppressor comutation. Our observation of a potential negative predictive effect of TP53/KRAS comutation requires validation.

Validation of Progression-Free Survival as a Surrogate Endpoint for Overall Survival in Malignant Mesothelioma: Analysis of Cancer and Leukemia Group B and North Central Cancer Treatment Group (Alliance) Trials

PURPOSE

The aim of this study was to investigate whether progression-free survival (PFS) can be considered a surrogate endpoint for overall survival (OS) in malignant mesothelioma.

MATERIALS AND METHODS

Individual data were collected from 15 Cancer and Leukemia Group B (615 patients) and 2 North Central Cancer Treatment Group (101 patients) phase II trials. The effects of 5 risk factors for OS and PFS, including age, histology, performance status (PS), white blood cell count, and European Organisation for Research and Treatment of Cancer (EORTC) risk score, were used in the analysis. Individual-level surrogacy was assessed by Kendall's tau through a Clayton bivariate Copula survival (CBCS) model. Summary-level surrogacy was evaluated via the association between logarithms of the hazard ratio (log HR)-log HR_OS and log HR_PFS-measured in R² from a weighted least-square (WLS) regression model and the CBCS model.

RESULTS

The median PFS for all patients was 3.0 months (95% confidence interval [CI], 2.8-3.5 months) and the median OS was 7.2 months (95% CI, 6.5-8.0 months). Moderate correlations between PFS and OS were observed across all risk factors at the individual level, with Kendall's tau ranging from 0.46 to 0.47. The summary-level surrogacy varied among risk factors. The Copula R² ranged from 0.51 for PS to 0.78 for histology. The WLS R² ranged from 0.26 for EORTC and PS to 0.67 for age.

CONCLUSIONS

The analyses demonstrated low to moderate individual-level surrogacy between PFS and OS. At the summary level, the surrogacy between PFS and OS varied significantly across different risk factors. With a short postprogression survival and a moderate correlation between PFS and OS, there is no evidence that PFS is a valid surrogate endpoint for OS in malignant mesothelioma. The Oncologist 2017;22:189-198Implications for Practice: For better disease management and for more efficient clinical trial designs, it is important to know if progression-free survival (PFS) is a good surrogate endpoint for overall survival in malignant mesothelioma. With a relatively large database of 17 phase II trials and 716 patients from Cancer and Leukemia Group B and North Central Cancer Treatment Group, we conducted statistical analyses and found that there is no evidence to suggest that PFS is a valid surrogate endpoint for OS for malignant mesothelioma. Future research work is needed to find alternative surrogate endpoints for OS.

A 10-Gene Yin Yang Expression Ratio Signature for Stage IA and IB Non-Small Cell Lung Cancer

INTRODUCTION

Lung cancer is the leading killer cancer worldwide. There is an urgent need for easy-to-use and robust clinical gene signatures for improved prognosis and treatment prediction.

METHODS

We used a gene expression signature termed the Yin and Yang mean ratio (YMR), which is based on two groups of genes with opposing function, to determine lung cancer prognosis. The YMR signature represents the relative state of an individual tumor on a gene expression spectrum ranging from malignancy to the normal healthy lung. The genes in the YMR signature have therefore been determined independently of survival time, which is different from previous regression models. We then leveraged the cross-platform utility of the YMR signature to optimize the signature into a smaller set of genes that validated the robustness of the signature in many independent lung cancer expression data sets.

RESULTS

Four Yin and six Yang genes were optimized using 741 NSCLC cases from diverse platforms, including microarray and RNA sequencing. The 10-gene signature demonstrated significant differences in survival in eight individual independent data sets and a larger combined 1346-patient data set. When multivariate analysis taking into account other common predictors of survival was used, the 5-year recurrence-free rate of YMR (p = 6.4 × 10^-6, HR =1.71 [1.36-2.16]) was secondary only to stage. The YMR signature significantly separated high- and low-risk patients with stage IA or 1B adenocarcinoma and squamous cell carcinomas of all stages. The YMR signature can also predict the benefit of adjuvant chemotherapy in high-risk patients with stage I NSCLC.

CONCLUSIONS

The YMR signature has great potential for guiding clinical management for NSCLC, particularly early-stage disease. The signature appears more reproducible than older signatures and functions using a variety of common gene expression platforms.

Prognostic Effect of Tumor Lymphocytic Infiltration in Resectable Non-Small-Cell Lung Cancer

PURPOSE

Tumor lymphocytic infiltration (TLI) has differing prognostic value among various cancers. The objective of this study was to assess the effect of TLI in lung cancer.

PATIENTS AND METHODS

A discovery set (one trial, n = 824) and a validation set (three trials, n = 984) that evaluated the benefit of platinum-based adjuvant chemotherapy in non-small-cell lung cancer were used as part of the LACE-Bio (Lung Adjuvant Cisplatin Evaluation Biomarker) study. TLI was defined as intense versus nonintense. The main end point was overall survival (OS); secondary end points were disease-free survival (DFS) and specific DFS (SDFS). Hazard ratios (HRs) and 95% CIs associated with TLI were estimated through a multivariable Cox model in both sets. TLI-histology and TLI-treatment interactions were explored in the combined set.

RESULTS

Discovery and validation sets with complete data included 783 (409 deaths) and 763 (344 deaths) patients, respectively. Median follow-up was 4.8 and 6 years, respectively. TLI was intense in 11% of patients in the discovery set compared with 6% in the validation set (P < .001). The prognostic value of TLI in the discovery set (OS: HR, 0.56; 95% CI, 0.38 to 0.81; P = .002; DFS: HR, 0.59; 95% CI, 0.42 to 0.83; P = .002; SDFS: HR, 0.56; 95% CI, 0.38 to 0.82; P = .003) was confirmed in the validation set (OS: HR, 0.45; 95% CI, 0.23 to 0.85; P = .01; DFS: HR, 0.44; 95% CI, 0.24 to 0.78; P = .005; SDFS: HR, 0.42; 95% CI, 0.22 to 0.80; P = .008) with no heterogeneity across trials (P ≥ .38 for all end points). No significant predictive effect was observed for TLI (P ≥ .78 for all end points).

CONCLUSION

Intense lymphocytic infiltration, found in a minority of tumors, was validated as a favorable prognostic marker for survival in resected non-small-cell lung cancer.

Subtype Classification of Lung Adenocarcinoma Predicts Benefit From Adjuvant Chemotherapy in Patients Undergoing Complete Resection

PURPOSE

The classification for invasive lung adenocarcinoma by the International Association for the Study of Lung Cancer, American Thoracic Society, European Respiratory Society, and WHO is based on the predominant histologic pattern-lepidic (LEP), papillary (PAP), acinar (ACN), micropapillary (MIP), or solid (SOL)-present in the tumor. This classification has not been tested in multi-institutional cohorts or clinical trials or tested for its predictive value regarding survival from adjuvant chemotherapy (ACT).

PATIENTS AND METHODS

Of 1,766 patients in the IALT, JBR.10, CALGB 9633 (Alliance), and ANITA ACT trials included in the LACE-Bio study, 725 had adenocarcinoma. Histologies were reclassified according to the new classification and then collapsed into three groups (LEP, ACN/PAP, and MIP/SOL). Primary end point was overall survival (OS); secondary end points were disease-free survival (DFS) and specific DFS (SDFS). Hazard ratios (HRs) and 95% CIs were estimated through multivariable Cox models stratified by trial. Prognostic value was estimated in the observation arm and predictive value by a treatment effect interaction with histologic subgroups. Significance level was set at .01 for pooled analysis.

RESULTS

A total of 575 patients were included in this analysis. OS was not prognostically different between histologic subgroups, but univariable DFS and SDFS were worse for MIP/SOL compared with LEP or ACN/PAP subgroup (P < .01); this remained marginally significant after adjustment. MIP/SOL patients (but not ACN/PAP) derived DFS and SDFS but not OS benefit from ACT (OS: HR, 0.71; 95% CI, 0.51 to 0.99; interaction P = .18; DFS: HR, 0.60; 95% CI, 0.44 to 0.82; interaction P = < .01; and SDFS: HR, 0.59; 95% CI, 0.42 to 0.81; interaction P = .01).

CONCLUSION

The new lung adenocarcinoma classification based on predominant histologic pattern was not predictive for ACT benefit for OS, but it seems predictive for disease-specific outcomes.

Minnelide: a novel therapeutic that promotes apoptosis in non-small cell lung carcinoma in vivo

BACKGROUND

Minnelide, a pro-drug of triptolide, has recently emerged as a potent anticancer agent. The precise mechanisms of its cytotoxic effects remain unclear.

METHODS

Cell viability was studied using CCK8 assay. Cell proliferation was measured real-time on cultured cells using Electric Cell Substrate Impedence Sensing (ECIS). Apoptosis was assayed by Caspase activity on cultured lung cancer cells and TUNEL staining on tissue sections. Expression of pro-survival and anti-apoptotic genes (HSP70, BIRC5, BIRC4, BIRC2, UACA, APAF-1) was estimated by qRTPCR. Effect of Minnelide on proliferative cells in the tissue was estimated by Ki-67 staining of animal tissue sections.

RESULTS

In this study, we investigated in vitro and in vivo antitumor effects of triptolide/Minnelide in non-small cell lung carcinoma (NSCLC). Triptolide/Minnelide exhibited anti-proliferative effects and induced apoptosis in NSCLC cell lines and NSCLC mouse models. Triptolide/Minnelide significantly down-regulated the expression of pro-survival and anti-apoptotic genes (HSP70, BIRC5, BIRC4, BIRC2, UACA) and up-regulated pro-apoptotic APAF-1 gene, in part, via attenuating the NF-κB signaling activity.

CONCLUSION

In conclusion, our results provide supporting mechanistic evidence for Minnelide as a potential in NSCLC.

Treatment of breast and lung cancer cells with a N-7 benzyl guanosine monophosphate tryptamine phosphoramidate pronucleotide (4Ei-1) results in chemosensitization to gemcitabine and induced eIF4E proteasomal degradation

The development of cancer and fibrotic diseases has been shown to be highly dependent on disregulation of cap-dependent translation. Binding protein eIF4E to N(7)-methylated guanosine capped mRNA has been found to be the rate-limiting step governing translation initiation, and therefore represents an attractive target for drug discovery. Our group has found that 7-benzyl guanosine monophosphate (7Bn-GMP) is a potent antagonist of eIF4E cap binding (K(d) = 0.8 μM). Recent X-ray crystallographic studies have revealed that the cap-dependent pocket undergoes a unique structural change in order to accommodate the benzyl group. Unfortunately, 7Bn-GMP is not cell permeable. Recently, we have prepared a tryptamine phosphoramidate prodrug of 7Bn-GMP, 4Ei-1, and shown that it is a substrate for human histidine triad nucleotide binding protein (hHINT1) and inhibits eIF4E initiated epithelial-mesenchymal transition (EMT) by Zebra fish embryo cells. To assess the intracellular uptake of 4Ei-1 and conversion to 7Bn-GMP by cancer cells, we developed a sensitive assay using LC-ESI-MS/MS for the intracellular quantitation of 4Ei-1 and 7Bn-GMP. When incubated with the breast cancer cell line MDA-231 or lung cancer cell lines H460, H383 and H2009, 4Ei-1 was found to be rapidly internalized and converted to 7Bn-GMP. Since oncogenic mRNAs are predicted to have the highest eIF4E requirement for translation, we carried out chemosensitization studies with 4Ei-1. The prodrug was found to chemosensitize both breast and lung cancer cells to nontoxic levels of gemcitabine. Further mechanistic studies revealed that the expressed levels of eIF4E were substantially reduced in cells treated with 4Ei-1 in a dose-dependent manner. The levels of eI4E could be restored by treatment with the proteasome inhibitor MG-132. Taken together, our results demonstrate that 4Ei-1 is likely to inhibit translation initiation by eIF4E cap binding by both antagonizing eIF4E cap binding and initiating eIF4E proteasomal degradation.

Cross-validation analysis of the prognostic significance of mucin expression in patients with resected non-small cell lung cancer treated with adjuvant chemotherapy: results from IALT, JBR.10 and ANITA

INTRODUCTION

CALGB 9633 was a randomized trial of observation versus adjuvant chemotherapy for patients with stage IB non-small cell lung cancer (NSCLC). In CALGB 9633, the presence of mucin in the primary tumor was associated with shorter disease-free survival (DFS; hazard ratio (HR) = 1.9, p = 0.002) and overall survival (OS; HR = 1.9, p = 0.004).

METHODS

To validate these results, mucin staining was performed on primary tumor specimens from 780 patients treated on IALT, 351 on JBR.10 and 150 on ANITA. The histochemical technique using mucicarmine was performed. The prognostic value of mucin for DFS and OS was tested in a Cox model stratified by trial and adjusted for clinical and pathological factors. A pooled analysis of all 4 trials was performed for the predictive value of mucin for benefit from adjuvant chemotherapy.

RESULTS

The cross-validation group had 48% squamous, 37% adenocarcinoma and 15% other NSCLC compared with 29%, 56%, and 15%, respectively in CALGB. Among 1262 patients with assessable results, mucin was positive in IALT 24%, JBR.10 30%, ANITA 22% compared with 45% in CALGB. Histology was the only significant covariate (p < 0.0001) in multivariate analysis with mucin seen more commonly in adenocarcinoma (56%) compared with squamous (5%) and other NSCLC (15%). Mucin was a borderline negative prognostic factor for DFS (HR = 1.2 [1.0-1.5], p = 0.06) but not significantly so for OS (HR=1.1 [0.9-1.4], p = 0.25). Prognostic value did not vary according to histology: HR = 1.3 [1.0-1.6] in adenocarcinoma vs. 1.6 [1.2-2.2] for DFS in other histology (interaction p = 0.69). Mucin status was not predictive for benefit from adjuvant chemotherapy (test of interaction: DFS p = 0.27; OS p = 0.49).

CONCLUSIONS

Mucin was less frequent in the cross-validation group due to its higher percentage of squamous cell carcinomas. The negative impact of mucin was confirmed for DFS but not for OS. Mucin expression was not predictive of overall survival benefit from adjuvant chemotherapy.

Yin Yang gene expression ratio signature for lung cancer prognosis

Many studies have established gene expression-based prognostic signatures for lung cancer. All of these signatures were built from training data sets by learning the correlation of gene expression with the patients' survival time. They require all new sample data to be normalized to the training data, ultimately resulting in common problems of low reproducibility and impracticality. To overcome these problems, we propose a new signature model which does not involve data training. We hypothesize that the imbalance of two opposing effects in lung cancer cells, represented by Yin and Yang genes, determines a patient's prognosis. We selected the Yin and Yang genes by comparing expression data from normal lung and lung cancer tissue samples using both unsupervised clustering and pathways analyses. We calculated the Yin and Yang gene expression mean ratio (YMR) as patient risk scores. Thirty-one Yin and thirty-two Yang genes were identified and selected for the signature development. In normal lung tissues, the YMR is less than 1.0; in lung cancer cases, the YMR is greater than 1.0. The YMR was tested for lung cancer prognosis prediction in four independent data sets and it significantly stratified patients into high- and low-risk survival groups (p = 0.02, HR = 2.72; p = 0.01, HR = 2.70; p = 0.007, HR = 2.73; p = 0.005, HR = 2.63). It also showed prediction of the chemotherapy outcomes for stage II & III. In multivariate analysis, the YMR risk factor was more successful at predicting clinical outcomes than other commonly used clinical factors, with the exception of tumor stage. The YMR can be measured in an individual patient in the clinic independent of gene expression platform. This study provided a novel insight into the biology of lung cancer and shed light on the clinical applicability.

Pooled analysis of the prognostic and predictive effects of KRAS mutation status and KRAS mutation subtype in early-stage resected non-small-cell lung cancer in four trials of adjuvant chemotherapy

PURPOSE

We undertook this analysis of KRAS mutation in four trials of adjuvant chemotherapy (ACT) versus observation (OBS) to clarify the prognostic/predictive roles of KRAS in non-small-cell lung cancer (NSCLC).

METHODS

KRAS mutation was determined in blinded fashion. Exploratory analyses were performed to characterize relationships between mutation status and subtype and survival outcomes using a multivariable Cox model.

RESULTS

Among 1,543 patients (763 OBS, 780 ACT), 300 had KRAS mutations (codon 12, n = 275; codon 13, n = 24; codon 14, n = 1). In OBS patients, there was no prognostic difference for overall survival for codon-12 (mutation v wild type [WT] hazard ratio [HR] = 1.04; 95% CI, 0.77 to 1.40) or codon-13 (HR = 1.01; 95% CI, 0.47 to 2.17) mutations. No significant benefit from ACT was observed for WT-KRAS (ACT v OBS HR = 0.89; 95% CI, 0.76 to 1.04; P = .15) or codon-12 mutations (HR = 0.95; 95% CI, 0.67 to 1.35; P = .77); with codon-13 mutations, ACT was deleterious (HR = 5.78; 95% CI, 2.06 to 16.2; P < .001; interaction P = .002). There was no prognostic effect for specific codon-12 amino acid substitution. The effect of ACT was variable among patients with codon-12 mutations: G12A or G12R (HR = 0.66; P = .48), G12C or G12V (HR = 0.94; P = .77) and G12D or G12S (HR = 1.39; P = .48; comparison of four HRs, including WT, interaction P = .76). OBS patients with KRAS-mutated tumors were more likely to develop second primary cancers (HR = 2.76, 95% CI, 1.34 to 5.70; P = .005) but not ACT patients (HR = 0.66; 95% CI, 0.25 to 1.75; P = .40; interaction, P = .02).

CONCLUSION

KRAS mutation status is not significantly prognostic. The potential interaction in patients with codon-13 mutations requires validation. At this time, KRAS status cannot be recommended to select patients with NSCLC for ACT.

ERCC1 isoform expression and DNA repair in non-small-cell lung cancer

BACKGROUND

The excision repair cross-complementation group 1 (ERCC1) protein is a potential prognostic biomarker of the efficacy of cisplatin-based chemotherapy in non-small-cell lung cancer (NSCLC). Although several ongoing trials are evaluating the level of expression of ERCC1, no consensus has been reached regarding a method for evaluation.

METHODS

We used the 8F1 antibody to measure the level of expression of ERCC1 protein by means of immunohistochemical analysis in a validation set of samples obtained from 494 patients in two independent phase 3 trials (the National Cancer Institute of Canada Clinical Trials Group JBR.10 and the Cancer and Leukemia Group B 9633 trial from the Lung Adjuvant Cisplatin Evaluation Biology project). We compared the results of repeated staining of the entire original set of samples obtained from 589 patients in the International Adjuvant Lung Cancer Trial Biology study, which had led to the initial correlation between the absence of ERCC1 expression and platinum response, with our previous results in the same tumors. We mapped the epitope recognized by 16 commercially available ERCC1 antibodies and investigated the capacity of the different ERCC1 isoforms to repair platinum-induced DNA damage.

RESULTS

We were unable to validate the predictive effect of immunostaining for ERCC1 protein. The discordance in the results of staining for ERCC1 suggested a change in the performance of the 8F1 antibody since 2006. We found that none of the 16 antibodies could distinguish among the four ERCC1 protein isoforms, whereas only one isoform produced a protein that had full capacities for nucleotide excision repair and cisplatin resistance.

CONCLUSIONS

Immunohistochemical analysis with the use of currently available ERCC1 antibodies did not specifically detect the unique functional ERCC1 isoform. As a result, its usefulness in guiding therapeutic decision making is limited. (Funded by Eli Lilly and others.).

Randomized phase II trial of erlotinib alone or with carboplatin and paclitaxel in patients who were never or light former smokers with advanced lung adenocarcinoma: CALGB 30406 trial

PURPOSE

Erlotinib is clinically effective in patients with non-small-cell lung cancer (NSCLC) who have adenocarcinoma, are never or limited former smokers, or have EGFR mutant tumors. We investigated the efficacy of erlotinib alone or in combination with chemotherapy in patients with these characteristics.

PATIENTS AND METHODS

Patients with advanced NSCLC (adenocarcinoma) who were epidermal growth factor receptor tyrosine kinase inhibitor and chemotherapy naive never or light former smokers (smokers of > 100 cigarettes and ≤ 10 pack years and quit ≥ 1 year ago) were randomly assigned to continuous erlotinib or in combination with carboplatin and paclitaxel (ECP) for six cycles followed by erlotinib alone. The primary end point was progression-free survival (PFS). Tissue collection was mandatory.

RESULTS

PFS was similar (5.0 v 6.6 months; P = .1988) in patients randomly assigned to erlotinib alone (arm A; n = 81) or to ECP (arm B; n = 100). EGFR mutation analysis was possible in 91% (164 of 181) of patients, and EGFR mutations were detected in 40% (51 of 128) of never smokers and in 42% (15 of 36) of light former smokers. In arm A, response rate (70% v 9%), PFS (14.1 v 2.6 months), and overall survival (OS; 31.3 v 18.1 month) favored EGFR-mutant patients. In arm B, response rate (73% v 30%), PFS (17.2 v 4.8 months), and OS (38.1 v 14.4 months) favored EGFR-mutant patients. Incidence of grades 3 to 4 hematologic (2% v 49%; P < .001) and nonhematologic (24% v 52%; P < .001) toxicity was greater in patients treated with ECP.

CONCLUSION

Erlotinib and erlotinib plus chemotherapy have similar efficacy in clinically selected populations of patients with advanced NSCLC. EGFR mutations identify patients most likely to benefit.

Abstract 2347: Translational control and lung cancer: eIF4F activation promotes tumorigenesis in vivo

Introduction: Lung cancer is the number one cancer killer in the United States accounting for nearly 30% of all cancer deaths. Survival rates continue to be abysmal with 5-year survival only 15% despite contemporary therapies, making it clear that novel therapeutic agents need to be discovered. The translation of mRNA into protein, a central control point in the gene expression pathway, has been increasingly implicated as a critical checkpoint in tumor genesis and progression. This checkpoint serves as a traffic signal at the intersection of cell pathways controlling cell division and survival. The cell machinery controlling the first step in protein synthesis, a hetero-trimer designated eIF4F, is stuck in the “on” position in many human cancers. When this happens cells evade restraints on proliferation and survival. The activation state of eIF4F is controlled at multiple levels with the primary mechanism being negative regulation by the 4E binding proteins (4E-BPs). 4E-BPs are inactivated when phosphorylated via mTOR in response to pro-growth signaling enabling eukaryotic initiation factor 4E (eIF4E), the rate-limiting component of the eIF4F heterotrimer, to activate translation. When de-phosphorylated, 4E-BPs bind eIF4E thereby inhibiting translation. In this study we examined the effects of eIF4F activation, via over-expression of eIF4E or knock-out of 4E-BPs, on lung tumorigenesis. Methods: Two transgenic mouse models of eIF4F activation were developed: 1) The αactin-eIF4E mouse model was crossed with the LSL-KrasG12D model resulting in the development of a 4E/KrasG12D double transgenic model. 2) The 4E-BP1, BP2 knockout mouse model was crossed with the LSL-KrasG12D model to produce a BPDKO/KrasG12D triple transgenic model. LSL-KrasG12D, 4E/KrasG12D, and BPDKO/KrasG12D mice were intranasally administered 2.5x104 infectious particles of replication deficient adenovirus expressing Cre recombinase (Ad-Cre). Lungs were resected at 30 days post transfection, formalin-fixed, and paraffin embedded. Lung sections underwent H&E staining as well as IHC for Ki-67. Slides were digitally scanned and analyzed with Aperio ImageScope Software. Results: At 30 days there is a clear shift towards increased tumorigenesis in 4E/KrasG12D and BPDKO/KrasG12D mice as determined by histology. Ki-67 staining indicates a significant increase in cellular proliferation in 4E/KrasG12D and BPDKO/KrasG12D mice. Conclusions: Activated eIF4F, achieved by eIF4E overexpression or 4E-BP1,2 knockout, promotes tumorigenesis in combination with oncogenic KrasG12D. These transgenic mouse models can be used to both deconstruct the translational checkpoint in lung cancer and as a treatment model for translational inhibitors.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2347. doi:1538-7445.AM2012-2347

Cross-validation study of class III beta-tubulin as a predictive marker for benefit from adjuvant chemotherapy in resected non-small-cell lung cancer: analysis of four randomized trials

BACKGROUND

The IALT, JBR.10, ANITA and Cancer and Leukemia Group B 9633 trials compared adjuvant chemotherapy with observation for patients with resected non-small-cell lung cancer (R-NSCLC). Data from the metastatic setting suggest high tumor class III beta-tubulin (TUBB3) expression is a determinant of insensitivity to tubulin-targeting agents (e.g. vinorelbine, paclitaxel). In 265 patients from JBR.10 (vinorelbine-cisplatin versus observation), high TUBB3 was an adverse prognostic factor and was associated (nonsignificantly) with 'greater' survival benefit from chemotherapy. We explored this further in additional patients from JBR.10 and the other three trials.

PATIENTS AND METHODS

TUBB3 immunohistochemical staining was scored for 1149 patients on the four trials. The original JBR.10 cut-off scores were used to classify tumors as TUBB3 high or low. The prognostic and predictive value of TUBB3 on disease-free survival (DFS) and overall survival (OS) was assessed by Cox models stratified by trial and adjusted for clinical factors.

RESULTS

High TUBB3 expression was prognostic for OS [hazard ratio (HR)=1.27 (1.07-1.51), P=0.008) and DFS [HR=1.30 (1.11-1.53), P=0.001). TUBB3 was not predictive of a differential treatment effect [interaction P=0.20 (OS), P=0.23 (DFS)]. Subset analysis (n=420) on vinorelbine-cisplatin gave similar results.

CONCLUSIONS

The prognostic effect of high TUBB3 expression in patients with R-NSCLC has been validated. We were unable to confirm a predictive effect for TUBB3.

Randomized phase II study of pemetrexed, carboplatin, and thoracic radiation with or without cetuximab in patients with locally advanced unresectable non-small-cell lung cancer: Cancer and Leukemia Group B trial 30407

PURPOSE

Cancer and Leukemia Group B conducted a randomized phase II trial to investigate two novel chemotherapy regimens in combination with concurrent thoracic radiation therapy (TRT).

PATIENTS AND METHODS

Patients with unresectable stage III non-small-cell lung cancer (NSCLC) were randomly assigned to carboplatin (area under the curve, 5) and pemetrexed (500 mg/m(2)) every 21 days for four cycles and TRT (70 Gy; arm A) or the same treatment with cetuximab administered concurrent only with TRT (arm B). Patients in both arms received up to four cycles of pemetrexed as consolidation therapy. The primary end point was the 18-month overall survival (OS) rate; if the 18-month OS rate was ≥ 55%, the regimen(s) would be considered for further study.

RESULTS

Of the 101 eligible patients enrolled (48 in arm A and 53 in arm B), 60% were male; the median age was 66 years (range, 32 to 81 years); 44% and 35% had adenocarcinoma and squamous carcinoma, respectively; and more patients enrolled onto arm A compared with arm B had a performance status of 0 (58% v 34%, respectively; P = .04). The 18-month OS rate was 58% (95% CI, 46% to 74%) in arm A and 54% (95% CI, 42% to 70%) in arm B. No significant difference in OS between patients with squamous and nonsquamous NSCLC was observed (P = .667). The toxicities observed were consistent with toxicities associated with concurrent chemoradiotherapy.

CONCLUSION

The combination of pemetrexed, carboplatin, and TRT met the prespecified criteria for further evaluation. This regimen should be studied further in patients with locally advanced unresectable nonsquamous NSCLC.

Abstract 160: Altered levels of circulating microRNAs in the plasma of non-small cell lung cancer patients: Potential as biomarker

The development of molecular markers for lung cancer could offset the deficiencies of currently available early detection and staging approaches. To this end, blood markers are particularly attractive since samples are obtained in a minimally invasive way at any stage of lung carcinogenesis. In this study we compared the levels of 10 microRNAs (miR-21, miR-31, miR-155, miR-147, miR-218, miR-377, miR-551b*, miR-569, miR-1283, and miR-1468) in the blood plasma of 27 non-small-cell lung cancer (NSCLC) patients and 38 healthy controls, using quantitative reverse transcription- polymerase chain reaction (qRT-PCR), to determine if these miRNAs might have a diagnostic value for NSCLC. The results of the area under the receiver operating characteristic curve (ROC), which measures the ability of the test to correctly classify those with and without the disease, were 0.98, 1.00, 0.8, and 0.98 for miR-21, miR-155, miR-377 and miR-1468, respectively, indicating that plasma levels of miR-21, miR-155, miR-377 and miR-1468 are powerful discriminators between patients and controls. At the optimum cutoff point for the cycle threshold (CT) value of the four miRNAs, the sensitivities of miR-21, miR-155, miR-377 and miR-1468 were 92.5%, 100%, 84%, and 100%, respectively; the corresponding values for the test specificity were 100%, 100%, 88%, and 100%, respectively. These results indicate the great potential of miR-21, miR-155, miR-377 and miR-1468 as diagnostic markers for NSCLC but need to be proved in prospective studies with larger samples.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 160. doi:10.1158/1538-7445.AM2011-160

Retraction: A genomic strategy to refine prognosis in early-stage non-small-cell lung cancer. N Engl J Med 2006;355:570-80

To the Editor: We would like to retract our article, "A Genomic Strategy to Refine Prognosis in Early-Stage Non-Small-Cell Lung Cancer,"(1) which was published in the Journal on August 10, 2006. Using a sample set from a study by the American College of Surgeons Oncology Group (ACOSOG) and a collection of samples from a study by the Cancer and Leukemia Group B (CALGB), we have tried and failed to reproduce results supporting the validation of the lung metagene model described in the article. We deeply regret the effect of this action on the work of other investigators.

A phase II study of sorafenib in malignant mesothelioma: results of Cancer and Leukemia Group B 30307

HYPOTHESIS

Malignant mesotheliomas (MMs) express vascular endothelial growth factor receptor (VEGFR), platelet-derived growth factor receptor, and cKIT. Sorafenib is a potent inhibitor of the ras/raf/MEK pathway and also targets VEGFR and cKIT. We evaluated the activity of sorafenib in patients with unresectable mesothelioma.

METHODS

MM patients who had received 0 to 1 prior chemotherapy regimens were treated with sorafenib 400 mg orally twice daily continuously. The primary end point was objective response. ERK1/2 phosphorylation in archival tissues was correlated with response and survival.

RESULTS

A total of 51 patients were enrolled, 50 were evaluable and included in the analysis. Three patients had a partial response (6% [95% confidence interval = 1.3-16.6%]), and 27 (54% [95% confidence interval = 39.3-68.2%]) had stable disease. Median progression-free survival and median overall survival (OS) were 3.6 and 9.7 months, respectively. Median survival was superior in epithelioid histology versus other types (10.7 versus 3.7 months, p = 0.0179). The difference in median OS between pretreated and chemonaive patients was not statistically significant (13.2 versus 5 months, p = 0.3117). Low/negative baseline tumor phospho-ERK1/2 levels were associated with improved OS (13.9 versus 5.2 months, p = 0.0066).

CONCLUSION

Sorafenib has limited activity in advanced MM patients, similar to that seen with other VEGFR tyrosine kinase inhibitors. Additional studies of sorafenib in MM are not warranted.

CYFRA 21–1 (CYFRA) as a prognostic and predictive marker in advanced non-small cell lung cancer (NSCLC): CALGB 150304

11020

Background: Cytokeratin 19 and its soluble fragment CYFRA have been studied as markers that may correlate with response to therapy and survival in NSCLC. As part of CALGB 30203, a randomized trial of carboplatin/gemcitabine with eicosanoid modulators (celecoxib, zileuton or both) in advanced NSCLC (Edelman JCO 2008), serum CYFRA levels were obtained prior to and during treatment. The objective of this study was to evaluate the possible correlation of CYFRA as a predictive and prognostic marker and to confirm a previous finding that a 27% reduction in CYFRA after one cycle (21 days) of treatment correlated with a longer survival (Vollmer Clin Ca Res, 2003). Methods: Paired specimens were available from 88 patients. CYFRA was measured at baseline and after cycles 1 and 2 using an electrochemoluminescent assay (Roche Diagnostics) on the ElecSys 2010 system as previously described. Using logarithm of the initial concentration and logarithm of the difference in concentrations, we analyzed these in relation to overall survival (OS) and failure free survival (FFS). Results: 1. Lower baseline CYFRA levels were associated with both longer overall survival and failure free survival (p = <0.0001 and p=0.0045). 2. Larger reductions in CYFRA levels correlated to longer overall survival and failure-free survival (p=0.0254 and p=0.0298). 3.We failed to replicate that a drop of >27% in CYFRA levels had statistical significance in overall or failure free survival (p=0.6489 and p=0.9636). Conclusions: CYFRA and change in CYFRA appear to be reliable markers in predicting the response to chemotherapy for nonsmall cell lung cancer; however, a precise threshold to mark response has yet to be determined.

No significant financial relationships to disclose.

Phase II study of pemetrexed, carboplatin, and thoracic radiation with or without cetuximab in patients with locally advanced unresectable non-small cell lung cancer: CALGB 30407

7505

Background: Cisplatin, etoposide and concurrent thoracic radiation has remained the standard treatment for locally advanced unresectable non small cell lung cancer (NSCLC) over the past two decades. The Cancer and Leukemia Group B (CALGB) conducted a phase II study using a novel chemotherapy regimen administered in systemically active doses with thoracic radiation (CALGB 30407). We previously reported the preliminary safety results (ASCO 2008, abstract 7518). Methods: Eligible patients with previously untreated stage III NSCLC received thoracic radiation (70 Gy) along with carboplatin (AUC 5) and pemetrexed 500 mg/m2 on day 1 administered intravenously every 21 days for 4 cycles (arm A) or the same chemotherapy regimen with weekly cetuximab for 6 weeks concurrent with radiation (arm B). All patients received four additional cycles of pemetrexed (500 mg/m2 every 21 days) as consolidation therapy. The primary endpoint was the percentage of patients who lived longer than 18 months after starting initial treatment. We planned to study the regimen (s) further if the 18 month survival rates equaled or exceeded 55%. Results: Characteristics of the 99 eligible pts (48 in arm A and 51 arm B) enrolled from 09/05 to 1/08: male 62%, 22% were 70 yrs or older. The most common histological type was adenocarcinoma (46% in Arm A and 41% in Arm B). Updated toxicity data (grade 3 or greater, %) by arms (arm A/arm B) for 106 pts: neutropenia 40/47; febrile neutropenia 8/6, thrombocytopenia 36/34, nausea/vomiting 8/10, esophagitis 32/24, skin rash 2/21 and fatigue 22/17. The median follow up time is 17 months. Preliminary efficacy data by arms (arm A/arm B) for 99 pts: complete or partial response 73% (95% CI 59–83)/71% (95% CI 57–81%), median failure free survival (months) 12.9 (95% CI 8.6–18.0)/10.3 (95% CI 8.7–18.9); 18 month survival 57% (95% CI 41–79)/47% (95% CI 33–67) and median survival (months) 22.3/18.7. Conclusions: The combination of pemetrexed, carboplatin and thoracic radiation has met the protocol-specified criteria for further study. Although it does not appear that the addition of cetuximab confers additional benefit in this setting, further follow-up is necessary.

[Table: see text]

Low incidence of brain metastasis as first site of relapse in patients with stage II and III non-small cell lung cancer

18051

Background: Lung cancer remains the leading cause of cancer mortality in both women and men in the United States. Despite recent advances in treatments, many patients with stage II and III non-small cell lung cancer (NSCLC) die of recurrent disease. Methods: A retrospective review was conducted to determine the incidence of brain metastasis as first site of relapse as well as other patterns of failure in patients with stage II and III NSCLC. From 1995 to 2003, 239 patients were identified from Minneapolis Veterans Affairs Medical Center tumor registry. Data was collected on the following variables to identify prognostic factors for brain metastasis and others patterns of failure: patient’s age, tumor histology, tumor size, nodal status, use of adjuvant chemotherapy, and type of adjuvant chemotherapy. Results: Of the 239 patients, only 12 (5%) had brain metastasis as first site of relapse. Median survival for patients with brain metastasis was 0.9 year (95% CI, 0.75–1.50). Out of 12 patients, 8 (67%) developed brain metastasis between 6 and 12 months after the initial diagnosis, 3 (25%) developed brain metastasis between 12 and 18 months and 1 (8%) developed brain metastasis as first site of relapse more than 18 months after initial diagnosis. Other patterns of failure were as follows: Thorax 36%, primary site 22%, primary + thorax 14% and distant metastasis 32%. Among 88 patients who underwent surgery as a part of definitive therapy, thorax was again the most common site of relapse (23%). Multivariate analysis showed that use of non-platinum based chemotherapy is a significant risk factor for relapse (p=0.02). Conclusion: Brain metastasis as first site of relapse is uncommon in patients with stage II and III NSCLC. Due to very low incidence of brain metastasis in this cohort of patients, prophylactic cranial radiation (which is the focus of few ongoing clinical trials) may cause more harm than good.

No significant financial relationships to disclose.

A genomic strategy to refine prognosis in early-stage non-small-cell lung cancer

BACKGROUND

Clinical trials have indicated a benefit of adjuvant chemotherapy for patients with stage IB, II, or IIIA--but not stage IA--non-small-cell lung cancer (NSCLC). This classification scheme is probably an imprecise predictor of the prognosis of an individual patient. Indeed, approximately 25 percent of patients with stage IA disease have a recurrence after surgery, suggesting the need to identify patients in this subgroup for more effective therapy.

METHODS

We identified gene-expression profiles that predicted the risk of recurrence in a cohort of 89 patients with early-stage NSCLC (the lung metagene model). We evaluated the predictor in two independent groups of 25 patients from the American College of Surgeons Oncology Group (ACOSOG) Z0030 study and 84 patients from the Cancer and Leukemia Group B (CALGB) 9761 study.

RESULTS

The lung metagene model predicted recurrence for individual patients significantly better than did clinical prognostic factors and was consistent across all early stages of NSCLC. Applied to the cohorts from the ACOSOG Z0030 trial and the CALGB 9761 trial, the lung metagene model had an overall predictive accuracy of 72 percent and 79 percent, respectively. The predictor also identified a subgroup of patients with stage IA disease who were at high risk for recurrence and who might be best treated by adjuvant chemotherapy.

CONCLUSIONS

The lung metagene model provides a potential mechanism to refine the estimation of a patient's risk of disease recurrence and, in principle, to alter decisions regarding the use of adjuvant chemotherapy in early-stage NSCLC.

A genomic strategy to refine prognosis in early stage non-small cell lung carcinoma (NSCLC)

7026

Background. Although stage-specific classification identifies appropriate populations for adjuvant chemotherapy, this is likely an imprecise predictor for the individual patient with early stage NSCLC. Methods. Using previously-described methodologies that employ DNA microarray data, multiple gene expression profiles (‘metagenes’) that predict risk of recurrence in patients with stage I disease were identified. This analysis used an initial ‘test’ cohort of patients with NSCLC (n = 89) that represented an equal mix of squamous cell and adenocarcinoma. Also, each histologic subset had equal number of patients who survived more than 5 years and those who died within 2.5 years of initial diagnosis. The performance of the metagene-based model generated on the training cohort was then evaluated in independent ‘validation’ sets, including two multi-center cooperative group studies (ACOSOG Z0030 and CALGB 9761). Importantly, the CALGB validation was performed in a blinded fashion. Results. Classification tree analyses that sample multiple gene expression profiles were used to develop a model of recurrence, termed the Lung Metagene Model, that accurately assesses prognosis (risk of recurrence and survival), performing significantly (p<0.001, odds ratio: 16.1, multivariate analysis) better than pathologic stage, T-size, nodal status, age, gender, histologic subtype and smoking history. The accuracy of prognosis using the Lung Metagene Model exceeded 90% (leave-one-out cross validation) in the initial training set (n = 89), 72% in the ACOSOG (n = 25), and 81% in the CALGB (n = 84) datasets. The prognostic accuracy was consistent across histologic subtypes and stages of NSCLC. Importantly, this provides an opportunity to re-classify stage IA patients to identify a subset of ‘high risk’ patients that may benefit from adjuvant chemotherapy. Further, stage IB and II patients identified as ‘low risk’ for recurrence, and who present co-morbidities, could potentially be candidates for observation, and those patients predicted to be at ‘high risk’ may benefit from novel therapeutic trials. Conclusions. The Lung Metagene Model provides a mechanism to refine the estimation of an individual patient’s risk for disease recurrence and thus guide the use of adjuvant chemotherapy in NSCLC.

No significant financial relationships to disclose.