Yang, Ping

11119 Background: Evaluation of prognostic factors in carcinoid tumors of the lung is limited due to the rarity of disease. This study assessed Ki-67 expression and other clinical variables as prognostic factors in 262 patients. Methods: A systematic search of Mayo Clinic lung cancer epidemiology and tumor registry databases from 1997 to 2009 identified 449 consecutive patients, with 262 having available tissue blocks [40 atypical carcinoids (AC) and 222 typical carcinoids (TC)]. Clinical data were collected by chart review. Tissue blocks were reviewed by 1/3 pathologists using WHO criteria. Tumors were tested for the Ki-67 index using digital image analysis (tumor tracing) by two operators. The association and predictive value of the factors with recurrence-free and overall survival (RFS and OS) were explored using univariable Cox proportional Hazards model and concordance (c) index. Results: Age, stage, smoking history, lymph node (LN) involvement and Ki-67 index were significant prognostic factors for RFS and OS. Median follow-up on alive-patients is 5 years (range: 0.006-5). Median percentage of Ki-67 index of AC and TC were 1.61% and 0.56% (P<0.0001), respectively. Patients with Ki-67 ≥ 1% had significantly worse RFS (HR=3.69, P<0.0001) and OS (HR=3.69, P=0.0007) compared with Ki-67 < 1% group. The c-index of Ki-67 (0.65) was comparable to the pathologic distinction between AC and TC (0.62 for original diagnosis and 0.63 for central-reviewed diagnosis). Conclusions: Ki-67 index cutoff value of 1% is a valuable prognostic biomarker for pulmonary carcinoids based on this large cohort. Our data also provide strong evidence for clinical variables such as age, stage, smoking history, and LN involvement as clinical prognostic factors in pulmonary carcinoids. A prognostic calculator incorporating Ki-67 and clinical variables is under development. [Table: see text]

7545 Background: Interpretation of lung cancer clinical trials is complicated by the heterogeneity of the patient population due to disease burden and comorbidities making pre-trial assessment of OS probability challenging. Methods: To create and validate a scoring system to estimate OS and improve the quality of future trials, this study evaluated the pretreatment prognostic factors of 2,442 pts with NSCLC. Univariate (UV) and multivariate (MV) Cox models were used to evaluate the prognostic importance of each baseline factor on OS. Those prognostic factors significant on both UV and MV analyses that were used to develop the scoring system included overall quality of life, age, sex, stage, ECOG performance status, the presence of other cancers, and smoking cessation. The score for each factor was determined by dividing the 5-year OS rate (in %) by 10 and summing these scores to form a total score. Multivariate models and the score for each factor were validated using bootstrapping with 1000 iterations from the original samples. Results: The score for each factor ranged from 1 to 7 points and the total scores ranged between 23 and 39 points. Higher scores reflected better OS. Categorization of the score was delineated first by clinician expert opinion (see Table) and then by multiple statistically defined empirical cut points. All categorization schemes demonstrated successful prognostic power. The bootstrap method confirmed the reliability of multivariate Cox model and score (Spearman correlation coefficient= 0.45). Conclusions: Prognostic factors significantly associated with OS on both UV and MV analysis were used to construct a valid scoring system which can be used to predict survival of NSCLC pts. This scoring system can be used by clinicians in counseling pts and for stratification in future trial design. [Table: see text]

13013 Background: The glutathione metabolic pathway is directly involved in the inactivation of platinum compounds. Our earlier work indicated that genotypes corresponding to varied glutathione-related enzyme activities may predict survival in patients with advanced lung cancer. Herein, we evaluated the role of glutathione-related genotypes on clinical outcomes in stage IIIB/IV non-small cell lung cancer patients who were stable or responding from one prior platinum-based chemotherapy. Methods: DNA samples from patients who had tumor regression or stable disease after treatment with one platinum based chemotherapy regimen were analyzed using 6 polymorphic DNA markers that encode 5 important enzymes in the glutathione metabolic pathway. The contrasting genotypes used in the analysis were GCLC (homozygous repeat 77 vs. heterozygous 7*), GPX1 (CC vs. other), GSTP1-I105V (AA vs. other), GSTP1-A114V (CC vs. other), GSTM1 (null vs. present), and GSTT1 (null vs. present). Multivariable Cox proportional hazards models adjusted for age, gender, treatment arm, ECOG performance status, stage, and prior tumor response, were used to evaluate the prognostic significance of the genotypes at each locus. Results: Data from 112 patients with a median follow-up of 10.6 (range: 0.4–56.3) months was used. No significant difference in time to disease progression was observed for any of the genotypes. Among the 6 genomic DNA markers, the GCLC genotype was an important prognostic factor for overall survival after adjusting for other factors. In particular, patients carrying a 77 repeat genotype (homozygous) had a significantly worse survival (Hazard ratio = 1.67, 95% CI: 1.05–2.63). Conclusions: Genotypes of glutathione-related enzymes, especially GCLC, may be used as host factors in predicting patients’ prognosis after platinum-based chemotherapy. Further investigation to define and measure the effects of these genes in chemotherapeutic regimens is needed. (This work was partly supported by NIH research grants CA77118, CA80127, and CA84354.) No significant financial relationships to disclose.

18037 Background: Platinum compounds are major chemotherapeutic agents in lung cancer and are metabolized by the glutathione pathway enzymes. We reported that genotypes of glutathione-related enzymes, especially GCLC, may be host factors in predicting survival of patients with stage IIIB/IV non-small cell lung cancer who were stable or responding from prior platinum-based chemotherapy (Yang et al., ASCO 2006). NCCTG investigators previously correlated allelic variants in 5-FU metabolizing genes with QOL in colorectal cancer patients (Sloan et al., ASCO 2004). We sought to evaluate the role of glutathione pathway genotypes on QOL. Methods: DNA samples were analyzed using 6 polymorphic DNA markers in the glutathione metabolic pathway. The contrasting genotypes in the analysis were GSTM1 and GSTT1 (null vs. present), GSTP1-I105V (AA vs. GA/GG), GSTP1-A114V (CC vs. CT/TT), GPX1 (CC vs. TT/TC), and GCLC (homozygous repeat 77 vs. heterozygous 7*). Forty-six patients completed the FACT-L and the UNISCALE QOL questionnaires at baseline and week-8, and we have results for all 6 genotypes. A clinically significant decline (CSD) in QOL was defined as a 10% decrease from baseline to week-8. A multivariate logistic regression model was used to evaluate the association of all 6 genotypes with a CSD in QOL. Results: Patients carrying the GPX1-CC genotype had a CSD in the UNISCALE (Odds Ratio (OR): 10.0; p=0.02), total FACT-L score (OR: 7.9; p=0.03), the FACT-L physical well being construct (OR: 13.7; p=0.02), and the FACT-L functional well being construct (OR: 5.3; p=0.05). Other constructs, i.e., emotional, social and family, and additional concerns were not significantly associated with the genotypes. Conclusions: Genotypes of glutathione-related enzymes, especially GPX1 may be inherited factors in predicting patients’ QOL after platinum-based chemotherapy. Further investigation to define and measure the direct or indirect effects of these genes on QOL is critical, particularly, via drug responses, toxicities, and disease recurrence. (This work was partly supported by NIH grants CA77118, CA80127, and CA84354.) No significant financial relationships to disclose.

7613 Background: Factors influencing the pattern of disease relapse after curative surgical resection in early stage NSCLC is unknown. We sought to evaluate the effect of tumor- and patient-related characteristics on the pattern of disease recurrence (local relapse and/or metastatic disease) and survival in relation to surgical resection for NSCLC. Methods: A consecutive retrospective series of 488 patients seen at Mayo Clinic Rochester who had complete resection of NSCLC between 1997 and 1998 was utilized. Cox proportional hazards model was used to evaluate the effect of age, gender, smoking status, TNM stage, number of lymph node (LN) involved, number of LN resected, and histopathologic diagnosis on RFS. Logistic regression was used to evaluate the effect on recurrence or death within the first 2 years after surgical resection. Results: Data on 342 patients with a median follow-up of 85 months (range: 0.1 to 162) are reported. 60% were male, and 81% had N0 stage at diagnosis. There were 26 (7.6%) never smokers. Median number of LN resected was 20 (interquartile range [IQR]: 14–29). Median age at surgery was 71 years (IQR: 64 to 76). A bi-modal pattern of local recurrence (N=62) after surgery for early stage NSCLC was observed, with 57% of patients having a local recurrence within 2 years and 21% of patients having a local recurrence from 5–7 years post-surgery. The median duration from surgery to first documented recurrence was 16 months (IQR: 8 to 39). While age, N stage, number of LN involved, and T stage were significant predictors of RFS univariately, only lesser LN resected (p=0.008), older age (p<0.0001) and higher T-stage (p=0.003) were significant adverse predictors of RFS in the multivariate analysis when adjusted for all factors. Higher T-Stage was associated with a significantly increased risk of recurrence or death within the first 2 years after surgical resection (p =0.004). Updated results using data from all 488 patients will be presented in the meeting. Conclusions: A trend towards a bimodal distribution of local recurrences after surgical resection of early stage NSCLC was observed. Increased number of LN resected, younger age and lower T stage were associated with better RFS. No significant financial relationships to disclose.

Abstract Background: Lung cancer kills more people than any other cancer in the United States. In addition to environmental factors, lung cancer has genetic risk factors as well, though the genetic etiology is still not well understood. We have performed whole exome sequencing on 262 individuals from 28 extended families with a family history of lung cancer. Methods: Parametric genetic linkage analysis was performed on these samples using two distinct analyses—the lung cancer only (LCO) analysis, where only patients with lung cancer were coded as affected, and the all aggregated cancers (AAC) analysis, where other cancers seen in the pedigree were coded as affected. Results: The AAC analysis yielded a genome-wide significant result at rs61943670 in POLR3B at 12q23.3. POLR3B has been implicated somatically in lung cancer, but this germline finding is novel and is a significant expression quantitative trait locus in lung tissue. Interesting genome-wide suggestive haplotypes were also found within individual families, particularly near SSPO at 7p36.1 in one family and a large linked haplotype spanning 4q21.3-28.3 in a different family. The 4q haplotype contains potential causal rare variants in DSPP at 4q22.1 and PTPN13 at 4q21.3. Conclusions: Regions on 12q, 7p, and 4q are linked to increased cancer risk in highly aggregated lung cancer families, 12q across families and 7p and 4q within a single family. POLR3B, SSPO, DSPP, and PTPN13 are currently the best candidate genes. Impact: Functional work on these genes is planned for future studies and if confirmed would lead to potential biomarkers for risk in cancer.

Abstract Lung cancer (LC) is the primary cause of cancer-related deaths in the United States. Whereas smoking and other environmental factors strongly increase LC risk, multiple genetic variants also contribute to risk in smokers. Furthermore, among smokers, some families have been identified with an abnormally high prevalence of LC, suggesting that unknown genetic factors can greatly increase LC risk in smokers. The typically short survival after LC diagnosis impedes collection of detailed genotypic information on any single large family pedigree, impairing the identification of putative high-risk factors. Therefore, the Genetic Epidemiology of LC Consortium has collected epidemiological and genetic data from a number of families with high numbers of LC cases from eight different sites across the US. In this study, we have obtained whole exome sequences (WES) from 290 members of 28 families, including 66 LC cases. We used a gene-based approach to allow for the possibility that different families may contain different variants of the same gene. Variants were filtered for i) allele frequency, ii) functional effect using combined annotation-dependent depletion (CADD), and, iii) affecting a gene with either a known or suspected role in cancer. We further selected variants based on their segregation in family pedigrees in a pattern consistent with a large effect on LC risk. Candidate LC risk genes were then identified as those represented in at least two families by the same or different variants. We further culled the list of genes by requiring the presence of at least one rare, functional variant enriched in the WES of 1060 cases relative to 899 controls from the Transdisciplinary Research on Cancer of the Lung consortium. This analysis narrowed our results to two genes, one being E2A, a member of the E family of bHLH transcription factors. Whereas loss-of-function mutations in E2A drive lymphoid cancers, the E2A protein also participates in an oncogenic heterodimer with TWIST1 that promotes the epithelial-mesenchymal transition and is implicated in multiple cancer types. Furthermore, the E2A/TWIST1 heterodimer is the primary TWIST1-containing complex implicated in oncogenesis, and silencing of E2A in KRAS-mutant non-small cell lung cancer (NSCLC) cell lines results in oncogene-stimulated senescence and apoptosis. Our data identified three distinct E2A variants present in all 10 sequenced LC cases in the 5 families in which those variants are found. Finally, two of these E2A variants are located only 57 nucleotides from each other, immediately adjacent to sequences encoding a transcription activation domain, suggesting that both variants alter the same specific protein function. These data identify E2A variants as likely high risk factors for LC in smokers and validate our general approach for identifying genetic factors with a large impact on LC risk. Citation Format: Claudio W. Pikielny, Anthony M. Musolf, Mariza de Andrade, Diptasri Mandal, Colette Gaba, Ping Yang, yafang Li, Ming You, Richard Wilson, Elena Y. Kupert, Marshall W. Anderson, Ann G. Schwartz, Susan M. Pinney, Ambrose I. Granizo-Mackenzie, Yanhong Liu, Ramaswamy Govindan, James McKay, Rayjean Hung, John K. Field, David C. Christiani, Joan E. Bailey-Wilson, Christopher I. Amos. Familial studies identify variants in the E2A transcription factor as putative risk factors for lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr LB-053.