Associations between baseline serum biomarker levels and cachexia/precachexia in pretreated non-small cell lung cancer (NSCLC) patients

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Background: We previously reported associations of pretreatment serum biomarkers with clinical outcomes in a cohort of advanced NSCLC patients that progressed on front-line therapy. This study aims to elucidate mechanisms underlying cancer cachexia/ pre-cachexia by evaluating relationships between baseline serum biomarker values and sequential changes in body weight, body mass index (BMI), and neutrophil/lymphocyte ratio (NLR) in NSCLC patients. Methods: We used Luminex immunobead assays to survey 101 protein biomarkers in sera from advanced NSCLC (n = 138) collected prior to their salvage regimen. Serial parameters associated with cancer cachexia included body weight, BMI, and NLR. Outcome variables (progression-free survival (PFS) and overall survival (OS)) were extracted with full IRB-approval. Biomarkers were evaluated as continuous variables with the cachexia surrogates using Pearson correlations, whereas associations of PFS and OS were accomplished with the Cox PH test. Results: High baseline values of BMI and low baseline NLR were associated with both OS and PFS (each p < 0.05), though weight failed to reach significance. PFS and OS were similarly associated with percent changes (relative to baseline) in weight (p < 0.01), BMI (p < 0.01), and NLR (p < 0.001). Thirteen biomarkers were found to be associated (p < 0.05) with baseline BMI values, including positive correlations with leptin, sol.VEGFR2, and c-peptide and inverse correlations with adiponectin, ferritin, ghrelin, IGFBP-1 and IL-8; fifteen biomarkers were associated with baseline NLR (all p < 0.05), including positive correlations with visfatin, insulin, and serum amyloid A and inverse correlations with IGF-II. Fifteen biomarkers were found to be associated (p < 0.05) in common with percent weight and BMI changes, including positive correlations with IGFBP-3 and inverse correlations with insulin, FGF-2, TNF-alpha, and resistin. Only prolactin and placental growth factor were found to be associated (p < 0.05) with percent change in NLR. Conclusions: A series of circulating protein biomarkers primarily connected with metabolic regulation and systemic inflammation/ acute phase response were found to be associated with cachexia/ pre-cachexia in NSCLC patients. Additional cohorts are currently being tested to verify these findings.

Real-world characterization of advanced/metastatic non-small cell lung cancer (aNSCLC) patients (pts) with rapid disease progression (RDP)

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Background: Despite advances in therapy, recent observational data shows that aNSCLC pts with RDP continue to have a poor prognosis. This retrospective, observational study characterizes the demographic, molecular, & treatment profile of pts with RDP. Methods: Adult aNSCLC pts receiving first-line (1L) platinum-based (Pt) therapy between 01/2014 - 12/2018 were identified in the COTA Real-World Evidence database and assigned to RDP (n = 280) & non-RDP (n = 1,212) cohorts based on time to progression during 1L Pt therapy (≤ 12 and > 12 weeks, respectively). Results: Of 1,492 eligible pts, the incidence of RDP was 19%. Mean age (±SD) was 64.6 (10.9) and 66.1 (10.2) in the RDP and non-RDP group, respectively (p = 0.04). Data showed RDP patients had higher percentage of stage IV disease at diagnosis (77 v 72, p < 0.01), higher histologic grade G3/G4 (37 v 29, p = 0.01), and PD-L1 negative (< 1% expression) status (p = 0.01). Table shows molecular profiling across cohorts. No notable difference in treatment patterns across 1L and 2L was observed. Conclusions: This study identifies stage IV disease at diagnosis, higher grade, & PD-L1 negative ( < 1% expression) as potential risk factors for RDP. A better understanding of this poor prognosis cohort may offer an opportunity to better optimize therapies & outcomes. [Table: see text]

Decreasing BMI/weight immediately prior to starting anti-PD-1/PDL-1 monoclonal antibodies for treatment for stage IV non-small cell lung cancer is associated with shorter progression-free survival

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Background: Currently, prognostic markers associated with immunotherapy treatment outcomes in patients with metastatic NSCLC include PDL-1 expression, tumor mutational burden (TBM), and neutrophil to lymphocyte ratio (NLR). In this study we examine the influence of pretreatment changes in weight, BMI, and NLR in 237 patients treated with anti-PD-1/PDL-1 therapy (ICI) at our institution. Methods: This was a retrospective analysis of previously-treated stage IV NSCLC patients who received ICI. Pretreatment (≥ 6 weeks before starting therapy) values of weight, BMI, and NLR were compared to baseline values and NLR was analyzed as continuum and according to standard cutoffs of 3.5 and 5. The same variables were correlated with progression-free survival (PFS) and overall survival (OS) using the Log-Rank test. Results: 237 patients were analyzed: 45% were male, 73% were Caucasian, 72% were former smokers, and 25% were age ≥ 75 years. 148 patients had pretreatment NLR values. Of these, 32% had a ratio < 3.5 and 54% had ratio < 5. 34% had increased NLR at baseline, the majority of which (48/77) had a > 5% increase. 187 patients had pretreatment weight and BMI. Of these, 14% had a pretreatment BMI < 20. 71% had a negative change in BMI and 29% had a > 5% decrease in BMI. 65% had a negative change in weight and 26% had a > 5% decrease in weight. BMI decrease greater than 5% (p = 0.0039), negative weight change (p = 0.0371), and pretreatment NLR > 5 (p = 0.0136) were associated with shorter PFS. Change in NLR trended towards decreased PFS but was not statistically significant (p = 0.07) though only 77 of 237 patients had both values available. There was no statistical PFS difference between patients less than or ≥ 75 years old. Conclusions: The results suggest that decrease in pretreatment BMI and weight along with high baseline NLR are associated with significantly shorter PFS in NSCLC treated with anti-PD-1/PDL-1 therapy. If confirmed, these observations raise the possibility that specific treatment which reverses cancer associated weight loss might enhance effectiveness of immunotherapy.

EGFR-Mutant Adenocarcinomas That Transform to Small-Cell Lung Cancer and Other Neuroendocrine Carcinomas: Clinical Outcomes

PURPOSE

Approximately 3% to 10% of EGFR (epidermal growth factor receptor) -mutant non-small cell lung cancers (NSCLCs) undergo transformation to small-cell lung cancer (SCLC), but their clinical course is poorly characterized.

METHODS

We retrospectively identified patients with EGFR-mutant SCLC and other high-grade neuroendocrine carcinomas seen at our eight institutions. Demographics, disease features, and outcomes were analyzed.

RESULTS

We included 67 patients-38 women and 29 men; EGFR mutations included exon 19 deletion (69%), L858R (25%), and other (6%). At the initial lung cancer diagnosis, 58 patients had NSCLC and nine had de novo SCLC or mixed histology. All but these nine patients received one or more EGFR tyrosine kinase inhibitor before SCLC transformation. Median time to transformation was 17.8 months (95% CI, 14.3 to 26.2 months). After transformation, both platinum-etoposide and taxanes yielded high response rates, but none of 17 patients who received immunotherapy experienced a response. Median overall survival since diagnosis was 31.5 months (95% CI, 24.8 to 41.3 months), whereas median survival since the time of SCLC transformation was 10.9 months (95% CI, 8.0 to 13.7 months). Fifty-nine patients had tissue genotyping at first evidence of SCLC. All maintained their founder EGFR mutation, and 15 of 19 with prior EGFR T790M positivity were T790 wild-type at transformation. Other recurrent mutations included TP53, Rb1, and PIK3CA. Re-emergence of NSCLC clones was identified in some cases. CNS metastases were frequent after transformation.

CONCLUSION

There is a growing appreciation that EGFR-mutant NSCLCs can undergo SCLC transformation. We demonstrate that this occurs at an average of 17.8 months after diagnosis and cases are often characterized by Rb1, TP53, and PIK3CA mutations. Responses to platinum-etoposide and taxanes are frequent, but checkpoint inhibitors yielded no responses. Additional investigation is needed to better elucidate optimal strategies for this group.

An open-label, phase II study of the polo-like kinase-1 (Plk-1) inhibitor, BI 2536, in patients with relapsed small cell lung cancer (SCLC)

OBJECTIVES

This phase II, open-label study was designed to evaluate the response rate to the polo-like kinase 1 (Plk-1) inhibitor BI 2536 in patients with sensitive-relapsed small cell lung cancer (SCLC). Secondary endpoints included progression-free survival (PFS), overall survival (OS), duration of response, and safety.

MATERIALS AND METHODS

Patients were treated with the recommended phase II dose of 200mg of BI 2536 intravenously every 21days. This was a two-stage design with an early stopping rule in place if responses were not seen in at least 2 of the first 18 enrolled patients.

RESULTS AND CONCLUSION

Twenty-three patients were enrolled in the study and 21 patients were evaluable for response. No responses were observed and all 23 patients have progressed. The median PFS was 1.4 months. Treatment was generally well tolerated and the most frequent adverse events were neutropenia, fatigue, nausea, vomiting, and constipation. BI 2536 is not effective in the treatment of sensitive relapsed SCLC. The criteria for expanding the trial to the second stage were not achieved, and the study was terminated for a lack of efficacy.

Clinician Perspectives on Current Issues in Lung Cancer Drug Development

Recent advances in molecularly targeted therapy and immunotherapy offer a glimmer of hope for potentially realizing the dream of personalized therapy for lung cancer. This article highlights current questions in clinical trial design, enrollment strategies and patient focused drug development, with particular emphasis on unique issues in trials of targeted therapy and immunotherapy.

Treatment of advanced squamous cell carcinoma of the lung: a review

Lung cancer remains the single deadliest cancer both in the US and worldwide. The great majority of squamous cell carcinoma (SCC) is attributed to cigarette smoking, which fortunately is declining alongside cancer incidence. While we have been at a therapeutic plateau for advanced squamous cell lung cancer patients for several decades, recent observations suggest that we are on the verge of seeing incremental survival improvements for this relatively large group of patients. Current studies have confirmed an expanding role for immunotherapy [including programmed cell death-1 (PD-1)/programmed cell death ligand 1 (PD-L1) and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) inhibition], a potential opportunity for VEGFR inhibition, and even future targets in fibroblast growth factor receptor (FGFR) and PI3K-AKT that collectively should improve survival as well as quality of life for those affected by squamous cell lung cancer over the next decade.

Randomized phase II study of cetuximab and bevacizumab in combination with two regimens of paclitaxel and carboplatin in chemonaive patients with stage IIIB/IV non-small-cell lung cancer

INTRODUCTION

We conducted a phase II study of dual-agent monoclonal antibody therapy consisting of cetuximab and bevacizumab in combination with paclitaxel and carboplatin chemotherapy in non-small-cell lung cancer.

METHODS

Patients with stage IIIB/IV nonsquamous non-small-cell lung cancer randomly received cetuximab (400 mg/m initially, 250 mg/m weekly thereafter) plus bevacizumab (15 mg/kg) for six cycles combined with paclitaxel (200 mg/m) and carboplatin (area under the curve 6) for either six cycles (six-cycle arm) or the first three cycles (three-cycle arm) (one cycle = 3 weeks). The primary objective was progression-free survival (PFS), estimated separately for each treatment arm.

RESULTS

In 121 patients, the median PFS was 6.05 months (95% confidence interval [CI]: 5.65, 7.03) in the six-cycle arm and 4.50 months (95% CI: 4.01, 5.42) in the three-cycle arm. Respective median overall survival times were 12.06 months (95% CI: 9.40, 19.25) and 11.63 months (95% CI: 6.64, 17.61). The tumor response rate was 51.7% (95% CI: 39.0%, 64.3%) and 44.3% (95% CI: 31.8%, 56.7%) in the six-cycle and three-cycle arms, respectively, with corresponding median response durations of 4.86 months (95% CI: 4.30, 7.16) and 3.94 months (95% CI: 2.92, 4.47). Quality of life was consistent across arms. Cetuximab-related grade 3/4 events in greater than 5% of patients (six-cycle arm, three-cycle arm) were dermatitis acneiform (6.9%; 8.6%) and fatigue (13.8%; 5.2%). Three patients died during the study from drug-related adverse events (one in the six-cycle arm and two in the three-cycle arm).

CONCLUSIONS

Both the regimens showed expected PFS and numerically comparable overall survival. Quality of life was similar in the two arms, and both the regimens were well tolerated.

Epithelial to mesenchymal markers and clinical outcomes on erlotinib in stage IV non-small cell lung cancer patients

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Background: An epithelial phenotype in NSCLC is associated with improved sensitivity to EGFR tyrosine kinase inhibitors (TKI). The best method to identify this subset is unknown (Richardson Anticancer Research 2012, Byers Clin Cancer Res 2012). This retrospective study correlates E-cadherin (Ecad) and vimentin (vim) immunohistochemistry (IHC) expression with outcomes in advanced NSCLC patients (pts) treated with erlotinib (E). Methods: Advanced NSCLC pts that received E were included if sufficient tumor was available from diagnosis. IHC scores for E-cad and vim were generated by multiplying frequency (0-4) by intensity (0-4). Log Rank was used to correlate IHC expression with progression free and overall survival (PFS, OS). Results were compared to a subset of pts with tissue from primary surgical NSCLC resection who later received E for recurrent disease. Results: 159 advanced NSCLC pts treated with E had tissue from diagnosis and IHC analysis. There was no correlation with PFS or OS on E and high/low vim or Ecad expression. Subtracting the IHC scores (vim minus ecad) created a difference score. A low difference score (n = 62) correlated with prolonged PFS (2.6 vs 1.9 months, p = .014 HR 1.52) compared with a high score, n = 97. Low difference score trended toward prolonged OS (p=.46) 33 of the patients had tissue available from primary surgical resection. The invasive front was examined for membranous E-cad and cytoplasmic vim (Allred score 0-8). Patients with low vim (< 4) and Ecad (>5), n= 19, trended toward prolonged PFS and OS on E compared with patients with high vim (>5) and low Ecad (<6), n=10 (4.2 vs 1.6 months and 15.5 vs 6.5 months, respectively, p=NS). Conclusions: In this retrospective analysis, using unselected, frequently small tissue specimens, the expression of ecad or vim alone by IHC did not correlate with outcomes for E treated patients. A complicated difference score (vimentin score minus ecadherin score) did correlate with PFS on E. Examining EMT markers at the invasive edge of resected NSCLC tumors might more accurately assess EMT activity and its relationship to outcomes when these pts are recommended EGFR-TKIs.

DNA repair gene promoter methylation in non-small cell lung cancer (NSCLC) patients treated with DNA damaging agents

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Background: Approximately 75% of NSCLC patients are advanced at time of diagnosis. Treatments include regimens of DNA-damaging and alkylating agents. Previous in vitro studies have shown that loss of BRCA1 and BRCA2 function through promoter methylation increases sensitivity to sapacitabine, suggesting that tumor cells may be protected by repair systems including BRCA-RAD50 and MGMT pathways induced by DNA damage. The purpose of this study is to investigate the effect of DNA repair gene promoter methylation on outcome of NSCLC patients treated with DNA damaging agents. DNA repair gene promoter hypermethylation may sensitize tumor cells to DNA damaging agents. Methods: The patient group of 240 patients included 135 early stage and 105 late stage (III/IV) cases. Chemotherapy regimens of late stage patients included carboplatin, cisplatin and gemcitabine, as well as other non-DNA damaging agents. Mean overall survival (OS) was 43.7 months. DNA was extracted from micro-dissected primary tumor, bisulfite converted and assessed by pyrosequencing to quantify methylation of cytosine nucleotides along the MGMT, BRCA1 and BRCA2 promoters. Results: Overall average methylation values were 8.4%, 7.3% and 8.3% for MGMT, BRCA1, BRCA2 respectively (compared to 3.2%, 3.6% and 7.3%, respectively, in nonmalignant lung tissue). Percent promoter methylation levels were not significantly correlated with age, gender, smoking status nor histology, with the exception of higher MGMT promoter methylation in smokers. Hypermethylation (greater than 10%) of BRCA1 and BRCA2 promoter was not significantly associated with survival in late stage patients (6.6 mos vs 6.8 mos; p=0.533) in this patient group, however, superior survival was observed with BRCA2 promoter hypermethylation when early stage patients were included (29.3 mos vs median not reached; p=0.045). Promoter hypermethylation of MGMTwas significantly associated with lower five-year survival rate in early stage patients (p=0.022). Conclusions: These data suggest epigenetic control of DNA repair gene expression can affect response to therapy. Further studies on specific treatment regimens will be required to definitively assess these effects.

Randomized phase III trial of pemetrexed (Pem)+carboplatin (Cb)+bevacizumab (Bev) followed by maintenance Pem+Bev (Pem arm) versus paclitaxel (Pac)+Cb+Bev followed by maintenance Bev (Pac arm) in patients (pts) with stage IIIb/IV nonsquamous non-small cell lung cancer (nsNSCLC) (POINTBREAK): African American (AA) subset

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Background: AAs with lung cancer (LC) have shorter survival than Caucasians (Cs). Despite a higher LC incidence among AAs than Cs (74.7 vs 64.4/100,000), AAs are underrepresented in clinical trials. There are no reports of randomized LC prospective trials reporting AA results. In POINTBREAK, we enrolled AAs at the same rate as the US incidence of NSCLC in AAs. We report efficacy/safety of AAs in both arms and efficacy/safety of AA and C within the Pem Arm. Methods: Data from AAs and Cs enrolled in POINTBREAK were analyzed. AAs in both arms were evaluated in a pre-specified analysis. Hazard ratio and p-values were derived from a multivariate Cox-PH model by adjusting stratification factors. Results: Of 939 randomized pts, 94 were AA and 805 were C. Demographics were comparable between AA/intent-to-treat populations (%): 56/53 male, 65/52 ≤65 years, 87/88 ever smoker, 86/90 stage IV, 43/44 Eastern Cooperative Oncology Group performance status 0. The table shows efficacy results. Among AAs, drug-related grade 3/4 adverse events (AEs) include (Pem Arm %/Pac Arm %): anemia (7.3/0), thrombocytopenia (9.8/4.0), fatigue (4.9/4.0), neutropenia (31.7/44.0), febrile neutropenia (0/4.0). Within Pem Arm, drug-related grade 3/4 AEs (AA%/ C%) were anemia (7.3/15.9), thrombocytopenia (9.8/25.5), fatigue (4.9/11.5), neutropenia (31.7/25.3), febrile neutropenia (0/1.6). Conclusions: Median OS for Pem Arm was not superior to Pac Arm in AAs. Within Pem Arm, there were no significant differences between AAs and Cs for efficacy outcomes. Both regimens were tolerable in AAs. Clinical trial information: NCT00762034. [Table: see text]

Thyroid transcription factor 1 (TTF-1) and overall survival in wild type EGFR patients treated with erlotinib

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Background: TTF-1 is a transcription factor involved in regulating epithelial to mesenchymal transition. TTF-1 has a favorable prognosis in early stage lung adenocarcinoma, although it’s prognostic value in erlotinib treated patients remains unknown (Somaiah ASCO 2011). The goal of this study was to validate the relationship between TTF-1 expression and clinical outcomes in wild-type (WT) stage IV non-small cell lung cancer (NSCLC) patients (pts) treated with erlotinib. Methods: Pts that received erlotinib were retrospectively analyzed by IHC for TTF-1 expression (positive = greater than 5% of tumor cells with moderate (2+) or strong (3+) nuclear staining). Pts’ tumors were considered WT if no mutations were detected in Exon 19 or L858R (Exon 21) using single-strand conformation polymorphism and sequence-specific polymerase chain reaction (PCR). Log Rank was used to correlate TTF-1 positivity with outcomes. Results: 216 pts were analyzed. EGFR activating gene mutations were found in 11.6% of cases. TTF-1 positivity was strongly correlated with the presence of an activating EGFR mutation (p=.0006, negative predictive value=97.7%). Of WT pts: median age was 65, 61% female, 15% never smokers. TTF-1 was positive in 8% of squamous cell and 71% of adenocarcinoma pts. In EGFR WT pts, the median progression free survival (PFS) in TTF-1 positive and negative pts was 2.1 vs. 1.6 months respectively, p=.255. TTF-1 strongly correlated with prolonged overall survival (OS) on erlotinib therapy in WT pts (6.2 vs. 3.2 months, log rank p=.004). After excluding for squamous cell histology, in TTF-1 positive EGFR WT pts there was still a highly significant correlation with prolonged OS on erlotinib (6.2 vs. 2.8 months, p=.001) and a trend toward prolonged PFS (2.2 vs. 1.4 months, p=.05). Conclusions: TTF-1 is related to the presence of exon 19 and 21 EGFR mutations in this group of NSCLC pts, and, similar to early stage lung cancer, TTF-1 appears to be at least a prognostic indicator for OS in stage IV WT EGFR NSCLC pts treated with erlotinib. Exploration of the potential predictive value of this readily available marker should be considered in pts with EGFR WT tumors treated with erlotinib.

Exploratory analyses of efficacy and safety of pemetrexed (Pem) plus bevacizumab (Bev) and bev alone as maintenance therapy (MT) in patients (Pts) with stage IIIb or IV nonsquamous non-small cell lung cancer (NS-NSCLC)

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Background: In a phase III superiority study, Pem+carboplatin (Cb)+Bev followed by Pem+Bev improved PFS compared with paclitaxel (Pac)+Cb+Bev followed by Bev in NS-NSCLC pts. Superior OS (primary endpoint) was not met. These analyses assessed the efficacy and safety in pts who received MT. Methods: Prespecified exploratory analyses were performed in the maintenance population (MP) and timed from the start of induction. Pts ≥18 years with stage IIIB/IV NS-NSCLC (ECOG status 0–1) from the multicenter, randomized, open-label, phase III superiority study were included in the MP if they received at least one dose of MT. For MT, pts received intravenous Pem 500 mg/m2+Bev 15 mg/kg (n=292) or Bev 15 mg/kg (n=298). OS, PFS, and safety were evaluated. Comparison is made to the intent-to-treat (ITT; Pem=472, Pac=467) or safety population (SP; Pem=442, Pac=443; received at least one dose of one drug). Results: Baseline pt and disease characteristics for the ITT and MP were similar between arms. In the ITT/MP population, the median number of cycles was 7/10 (range, 1-41/4–41) in the Pem arm and 6/9 (range, 1-39/5–39) in the Pac arm. In the ITT/MP, OS was 12.6/17.7 months (mos; Pem) and 13.4/15.7 mos (Pac). Survival rates (%) at 12 and 24 mos with Pem (ITT/MP) were 52.7/71.7 and 24.4/34.5; Pac, 54.1/66.5 and 21.2/26.5%. In pts not receiving MT, OS was 4.7 mos (Pem) and 6.1 mos (Pac). PFS (mos) in the ITT/MT was 6.0/8.6 (Pem) and 5.6/6.9 (Pac). In pts not receiving MT, PFS was 2.3 mos and 2.5 mos with Pem and Pac, respectively. From induction, both SP/MP had significantly more grade 3/4 thrombocytopenia, anemia, and fatigue with Pem and neutropenia and sensory neuropathy with Pac (p≤0.001). During MT only, the difference in grade 3/4 neutropenia rates between arms was no longer significant. Conclusions: Improved efficacy outcomes were consistent with previous Pem maintenance and Bev studies and no new toxicities were observed. Clinical trial information: NCT00762034.

Preoperative survivin, ERCC1, and PTEN expression in stage III non-small cell lung cancer (NSCLC) patients (pts) treated with neoadjuvant and definitive chemoradiation and association with overall survival (OS)

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Background: Thoracic radiation and concurrent chemotherapy consisting of platinum based doublets has produced modest improvement in long term survival for patient with locally advanced (LA) NSCLC. There is relatively little information regarding molecular profiles and outcome in LA-NSCLC patients (pts) treated with chemoradiation. The objective of this retrospective study is to evaluate potential relationships between expression of DNA repair enzyme ERCC1 and enzymes involved in cell survival – survivin and PTEN. Methods: Stage III NSCLC pts who were treated with chest radiation (40-60Gy) and concurrently with platinum doublet and who had sufficient pretreatment tissue were included in this study. Immunohistochemistry was used to detect nuclear and cytoplasmic expression (frequency 0-4 and intensity 0-4) of survivin, and PTEN, and for nuclear expression of ERCC1. Product of intensity and frequency was calculated for all markers and correlated with overall survival (OS). Results: 97 pts had adequate tumor samples for analysis. 53 women, median age 67. 48 pts with ERCC1 prod <=6 had longer OS than 41 pts with ERCC1 prod >6 (19.6 vs 1.0 months, p=0.034). 16 pts with ERCC1 prod >6, PETN prod <=6 and survivin prod >4 had significantly lower OS than 68 pts with ERCC1<=6, PETN >6 and survivin <=4 (17.2 vs 40.2 months, p<0.001). Conclusions: The association of inferior survival in LA-NSCLC pts whose tumors express high survivin, low PTEN, and high ERCC1, suggests that combining inhibitors of survivin and or of PI3KCA with chemoradiation and developing strategies to inhibit DNA repair might improve outcomes in this group of pts.

EGFR gene mutation and epithelial to mensenchymal transition (EMT) markers in advanced NSCLC patients treated with erlotinib

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Background: TTF-1 is a transcription factor involved in regulating epithelial to mesenchymal transition (EMT). Previous work in a clinically enriched non-small cell lung cancer (NSCLC) population suggested low probability of an EGFR activating gene mutation in the absence of TTF-1 positivity (Somaiah ASCO 2011). This study's goal was to validate the relationship of TTF-1 and other immunohistochemical (IHC) markers of EMT to the presence of an EGFR activating gene mutation in a diverse group of NSCLC patients treated with erlotinib. Methods: Patients receiving erlotinib at two midwest institutions were retrospectively analyzed by IHC for TTF-1 (Greater than 5% of tumor cells with moderate (2+) or strong (3+) nuclear staining considered positive) and for PTEN, Ecadherin,vimentin, beta catinin, and snail (frequency(0-4) times intensity(0-4)). Exon 19 and L858R mutations were detectedusing single-strand conformation polymorphism and sequence-specific polymerase chain reaction (PCR)).Fisher’s exact testand logistic regression wereused to correlate TTF-1(positive or negative) and the remaining EMT markers with the presence of EGFR mutation. Results: 216 patients were analyzed for EGFR activating gene mutations: 15% squamous, 80% smokers. EGFR mutation was found in 11.6% of cases. TTF-1 was present in 8% of squamous cell patients and 71% of adenocarcinoma patients. TTF-1 correlated with prolonged progression free survival (log rank p=.004). TTF-1 positivity was strongly correlated with the presence of mutation (p=.0006, negative predictive value=97.7%). Increasing Ecadherin and increasing PTEN expression by IHC correlated with the presence of EGFR gene mutation when measured on continuum (p=.006 and p=.04, respectively). Conclusions: Though retrospective, our work confirms the negative predictive value of TTF-1 for an EGFR activating gene mutation in a NSCLC cohort representative of a North American population.Though high PTEN and Ecadherin expression also correlated with EGFR mutation, TTF-1 positivity may be a more straight-forward marker that can select patients who should be screened for the mutation prior to initiation of first line therapy.

Panel of serum biomarkers to predict benefit from bevacizumab (BEV) in advanced NSCLC patients

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Background: BEV has produced modest benefits in patients (PTS) with advanced NSCLC. Identification of positive predictors for BEV would have important implications for individual PTS and health care costs. Methods: We performed a prospective exploratory analysis to identify serum biomarkers as predictors of improved outcomes with BEV. Pre treatment sera were collected from 93 pts prior to initiation of first line treatment for advanced NSCLC. Treatment drugs, including BEV, were prescribed according to treating physician’s discretion. Seventy two serum biomarkers, relevant to angiogenesis and tumor progression, were recorded using Luminex immunobead platform. Serum levels were correlated with progression free survival (PFS) and overall survival (OS) and compared between patient treated with or without BEV containing regimens, BEV + and BEV- groups respectively. Log-rank and interaction p value tests were used to identify markers associated with longer PFS and OS in the BEV+ group but not in BEV- group. Results: Characteristics for each group were: BEV+ (n=43, median age 65 y/o, 72% smokers, 60% females, 100% non-squamous). BEV– (n=50, median age 64 y/o, 84% smokers, 50% female, 70 % non-squamous). The BEV+ group had longer PFS (5.8 vs. 3.0 mos, log-rank p= 0.039) and OS (13.1 vs. 8.5 mos, log-rank p =0.11) when compared to the BEV- group. High serum levels of these markers resulted in a differential decreased hazard in the BEV+ group: PDGF-AB/BB (interaction p <0.01 for PFS, p=0.04 for OS), FGF (interaction p=0.15 for PFS, p<0.04 for OS), tenascin-c (interaction p=0.18 for PFS, p=0.04 for OS), RANTES (interaction p=0.04 for PFS, p=0.6 for OS), epiregulin (interaction p=0.31 for PFS, p=0.04 for OS) and anti-HGF (interaction p=0.18 for PFS, p=0.03 for OS). In the BEV+ group higher levels of PDGF-AB/BB were associated with a better outcome (log-rank p=0.05 and p=0.01 for PFS and OS respectively). We did not find significant correlations between serum levels of VEGF, anti-VEGF or VEGFR and benefit from BEV. Conclusions: This exploratory analysis suggests that these biomarkers may have predictive value for BEV in NSCLC PTS and should be considered for further studies.

Phase II study of single-agent navitoclax (ABT-263) and biomarker correlates in patients with relapsed small cell lung cancer

PURPOSE

Bcl-2 is a critical regulator of apoptosis that is overexpressed in the majority of small cell lung cancers (SCLC). Nativoclax (ABT-263) is a potent and selective inhibitor of Bcl-2 and Bcl-x(L). The primary objectives of this phase IIa study included safety at the recommended phase II dose and preliminary, exploratory efficacy assessment in patients with recurrent and progressive SCLC after at least one prior therapy.

EXPERIMENTAL DESIGN

Thirty-nine patients received navitoclax 325 mg daily, following an initial lead-in of 150 mg daily for 7 days. Study endpoints included safety and toxicity assessment, response rate, progression-free and overall survival (PFS and OS), as well as exploratory pharmacodynamic correlates.

RESULTS

The most common toxicity associated with navitoclax was thrombocytopenia, which reached grade III-IV in 41% of patients. Partial response was observed in one (2.6%) patient and stable disease in 9 (23%) patients. Median PFS was 1.5 months and median OS was 3.2 months. A strong association between plasma pro-gastrin-releasing peptide (pro-GRP) level and tumor Bcl-2 copy number (R = 0.93) was confirmed. Exploratory analyses revealed baseline levels of cytokeratin 19 fragment antigen 21-1, neuron-specific enolase, pro-GRP, and circulating tumor cell number as correlates of clinical benefit.

CONCLUSION

Bcl-2 targeting by navitoclax shows limited single-agent activity against advanced and recurrent SCLC. Correlative analyses suggest several putative biomarkers of clinical benefit. Preclinical models support that navitoclax may enhance sensitivity of SCLC and other solid tumors to standard cytotoxics. Future studies will focus on combination therapies.