Decker, Paul A.

2072 Background: Human glioma stem cells and xenograft lines are common translational models in neuro-oncology but it has not been established if they are genetically and phenotypically comparable. This study aimed to determine if human glioma xenografts and stem cell-derived tumors had similar genotypes. Methods: Matched glioma stem cell cultures and subcutaneous xenograft lines were generated from four human glioblastoma specimens (BT114, BT116, BT120, BT132). Comparison was made between subcutaneous stem cell-derived tumors (flank) and xenografts established in nude mice. Copy number variation (CNV) and gene expression microarray studies were performed. Results: Various differences in copy number and gene expression were seen. Observed CNVs included regions within EGFR, myc, and p16 (INK). For example, EGFR copy number was two fold higher in xenografts vs. stem cell-derived tumor in one line (BT114). This difference was corroborated by western blot. Other differences included a heat shock protein homolog (DNAJA4), tetraspanin 13, and a p53 family target gene (ISG20L1). Two lines (BT114, BT116) had a greater than two fold increase in DNAJA4 expression in xenografts vs. stem cell-derived tumors (p = 0.04, 0.01). Two cell lines (BT116, BT120) had a two to eight fold increase in tetraspanin 13 expression in xenografts (p = 0.02, 0.05). However, neither copy number nor gene expression variations were consistent across all cell lines. Conclusions: Xenografts and glioma stem cell-derived tumors established from the same patient specimens have distinct genotypes. Further work is needed to establish if these differences are random or represent characteristic changes selected by different in vitro or in vivo pressures. However, these variations raise questions regarding which model is ideal for studying glioma biology, and which ones best replicate glioma characteristics in human patients.

2025 Background: Although adjuvant radiation has demonstrated a clear survival benefit in anaplastic astrocytomas (AA), the role of concurrent temozolomide (TMZ) remains controversial. Methods: All adult patients diagnosed with AA from 2001 to 2011 and treated with standard doses of adjuvant radiation were identified retrospectively using the neuro-oncology database at the Mayo Clinic (Rochester, MN). Clinical data was extracted from the electronic medical record. IDH mutation status was also determined by obtaining either IDH1R132H immunostain on existing unstained slides or paraffin block sections, or by sequencing. Cumulative survival probabilities were estimated using the Kaplan-Meier method. Univariable and multivariable Cox proportional hazards regression models were fit to compare patients who did/did not receive TMZ. Results: 218 patients were identified that met inclusion criteria. 34 patients were excluded due to missing data on adjuvant chemotherapy. 146 patients had received adjuvant TMZ while 38 had not. Of these, IDH mutation status was determined on 124 patients who received TMZ and 33 of those who had not. The median duration of follow up was 36.4 months. On univariable analysis, adjuvant TMZ demonstrated a trend towards improved median survival from 35.2 to 53.1 months (p=0.06). As an independent variable, patients with IDH mutations had longer median survivals (111.7 months) when compared to IDH wild-type patients (23.3 months) (p<0.001). On multivariable analysis, five-year-survival was significantly impacted by receipt of adjuvant TMZ (HR = 0.56, p=0.03) and IDH mutation status remained a significant prognostic factor (HR = 0.19, p < 0.001) (see Table). Conclusions: IDH mutation strongly predicts a favorable outcome in patients with AA. Secondarily, concurrent TMZ is also associated with improved survival in patients with AA who are receiving adjuvant radiotherapy. [Table: see text]

4062 Background: Multiple clinical trials have incorporated preoperative chemotherapy and radiation (RT) in an attempt to improve local tumor control, distant disease failure and overall survival rates for locally advanced but resectable adenocarcinoma of the distal esophagus and gastroesophageal junction (GEJ). This multicenter, cooperative group study combined active chemotherapy agents cisplatin (C), docetaxel (D) and the targeted EGFR agent panitumumab (P) in the induction phase followed by concurrent chemotherapy (CDP) and radiation. Pathologic complete response (pCR), a surrogate for improved survival, was the primary endpoint. Methods: From 01/15/09 to 07/22/11, 70 patients (pts) with Siewert I or II adenocarcinomas and clinical stages T3N0M0, T2-3N1M0 or T2-3N0-1M1a (celiac LN ≤ 2 cm) were accrued. Patients received cisplatin (40 mg/m2), docetaxel (40 mg/m2) and panitumumab (6 mg/kg) on weeks 1, 3, 5, 7, 9 with RT (5040 cGy, 180 cGy/day x 28d) beginning week 5. The decision rule had a 90% power with a 0.10 significance level to detect a pCR rate of at least 35%. Secondary objectives included near-pathologic complete response (near-pCR), toxicity, and overall and disease-free survival rates. Results: Five pts were ineligible. Of the remaining 65 pts (59 M, 6 F; median age 61), 12 pts did not undergo surgery (5 progressed, 4 refused, 3 other). Of the 58 evaluable pts, the pCR rate was 32.8% (90% CI: 22.6% -42.9%) and near-pCR 22.4% (90% CI: 13.4%-31.4%). Total doses of C, D, and P were achieved in 76%, 80%, and 73%, respectively (n = 70). 66 pts (94%) received the total RT dose. Sixteen pts (23%) had a grade 4+ non-heme adverse event possibly related to treatment. Venous thrombosis (5 pts) was most common. Conclusions: The CDP regimen in the neoadjuvant setting in patients with esophageal adenocarcinomas is active (pCR + near-pCR = 55.2%) and feasible. The toxicity though tolerable is substantial.

1521 Background: Gliomas are known to progress from low to high grade at relapse, but the frequency is not well understood. It is unclear whether survival of these pts differ as a function of histologic subtype, and as measured from initial diagnosis and from relapse; yet such pts are frequently combined in clinical trials. Methods: Central review of paired glioma tissues obtained at initial diagnosis (DX) and recurrence was performed in 208 pts enrolled in prospective NCCTG trials (recurrence ≤ 90 d excluded). Kaplan-Meier, log rank, ANOVA, and chi-square tests were utilized. Results: Relapse from low (1–2) to high grade (3–4) occurred in 18/42 (43%) oligodendrogliomas (oligo), 28/41 (68%) oligoastrocytomas (OA), and 14/20 (70%) astrocytomas (astro); p=0.031. There were differences in median OS (in yrs; 95% CI) from initial DX: oligo-7.5 (5.0, 12.6); OA-4.5 (3.8, 5.6); and astro-3.3(1.8, 5.1), p=0.002; and OS from high grade recurrence: oligo-2.1 (0.9,3.0); OA-1.0 (0.8,1.3); and astro-0.7 (1.8, 5.1); p=0.02. Median OS from initial DX (yrs, 95% CI) also differed between primary (initial DX) GBM-1.7 (1.5–2.2); secondary (at recurrence) GBM-3.7 (2.8, 4.2) and non-GBM (initial+recurrence)- 5.5, (4.9–7.0) respectively, p < 0.001. Mean time to recurrence (TTR), (yrs ± S.D.) also differed: 1.1±1.1; 2.9±1.8; and 4.0±2.9, respectively, p < 0.001; as did median OS from recurrence (yrs, 95% CI) [0.7 (0.5, 1.1); 0.6, (0.5, 1.0); and 1.6 (1.1, 2.1), respectively], p <0.001. OS differed between primary vs. secondary GBM from time of initial DX (p=0.041) and also from recurrence (p=0.017). Conclusions: Low grade astro and OA progressed to grade 3–4 more frequently than did pure oligo; these groups had significant differences in OS from initial diagnosis and from recurrence. There were significant differences in OS between pts with primary and secondary GBM from initial diagnosis and recurrence. These data have important implications in design of clinical trials. [Table: see text] No significant financial relationships to disclose.

1509 Background: Lack of MGMT methylation in GBM tumors is associated with a worse outcome with combined radiation (RT) and temozolomide (TMZ) therapy, and it is unclear whether non-methylated tumors benefit from TMZ treatment. Methods: The potential benefits of concomitant or adjuvant TMZ relative to methylation status were evaluated in 10 GBM tumors established from patient samples and maintained by serial passage in mice. For each tumor line, 32 mice with established orthotopic xenografts were randomized to A) placebo, B) TMZ PO daily × 5 (120 mg/kg or 66 mg/kg, as indicated) C) RT, 2 Gy bid × 10 fx., D) combined TMZ and RT, and mice were followed until moribund. Efficacy was evaluated by regression modeling and Kaplan-Meier statistical analyses. Results: Six lines with non-methylated MGMT (GBM10, 14, 26, 28, 36, 43) and 4 with methylated MGMT (GBM8, 12, 16, 34) were evaluated, and complete results are available in 6 lines. In all tumor lines and at both dose levels, there was a significant benefit for TMZ relative to placebo (p<0.003). Both methylated tumors (GBM8 and 12) and one non-methylated tumor (GBM14) were markedly sensitive to TMZ with greater than a 50 day extension in survival with monotherapy. Individually and in a pooled analysis, there was no evidence for a synergistic interaction between TMZ and RT in the non-methylated tumors (p=0.91 for pooled analysis). In contrast, there was a striking degree of synergy in GBM12 (p<0.001) and at least additive effects of combined treatment in GBM8 (5 of 8 mice still surviving in the RT/TMZ arm). In a pooled analysis of these 2 MGMT methylated tumors, there was a trend towards synergy (p=0.11). Conclusions: TMZ treatment did not sensitize MGMT non-methylated tumors to radiation, and with one exception, these non-methylated tumors were only modestly sensitive to TMZ alone. In contrast, treatment with TMZ appears to sensitize MGMT-methylated tumors to radiation and monotherapy is associated with marked and significant benefit. [Table: see text] No significant financial relationships to disclose.

7555 Background: Lymph node status is a major determinant of stage and survival in patients with lung cancer; however, little information is available about the yield of a mediastinal lymphadenectomy done at the time of pulmonary resection. Methods: The ACOSOG Z0030 trial is a prospective, randomized trial of mediastinal lymph node sampling versus complete mediastinal lymphadenectomy during an operation for early stage lung cancer. Total enrollment from July 1999 to February 2004 was 1,111 patients, of which 1,023 were eligible and/or evaluable. There were 524 patients who underwent complete mediastinal lymph node resection after randomization to this arm that were declared eligible and/or evaluable with lymph node data available. The number of lymph nodes examined from each station was collected beginning in January 2002. Prospectively collected data from these patients was analyzed to determine the number of lymph nodes obtained. Results: Median age was 67 (range 37–87) and 267 (52%) were men. Histology was squamous cell in 141 (27%), adenocarcinoma in 227 (44%), large cell in 22 (4%), bronchoavelolar in 32 (6%) and other non-small cell in 99 (19%). There were 317 right sided cancers and 207 left sided cancers. For lymphadenectomy for cancers in the right lung the yield from station 2R was a median of 2 lymph nodes (range 1 to 15), station 4R was 2 (1 –17), station 7 was 2 (1–24), station 8 was 1 (1–5), station 9 was 1 (1–6) and station 10R was 1 (1–10). For lymphadenectomy for cancers on the left side the yield from station 2L was 2 (1–4), station 4L was 1 (1–12), station 5 was 2 (1–18), station 6 was 2 (1–11), station 7 was 2 (1–16), station 8 was 1 (1–3), station 9 was 1 (1–8) and 10L was 2 (1–12). The total number of lymph nodes or fragments obtained for right sided cancers was a median of 13.5 (range 1 to 56) and for left sided tumors 15 (range 4 to 81). Conclusions: Although high variability exists in the actual number of lymph nodes obtained from various nodal stations, a complete mediastinal lymphadenectomy should obtain one or more lymph nodes from each mediastinal station. Adequate mediastinal lymphadenectomy should include exploration and remove of lymph nodes from stations 2R, 4R, 7, 8, and 9 for right sided cancers and stations 4L, 5, 6, 7, 8 and 9 for left sided cancers. No significant financial relationships to disclose.

Background: Current cardiovascular disease (CVD) risk scores are derived from research cohorts and are particularly inaccurate in women, older adults, and those with missing data. To overcome these limitations, we aimed to develop a cohort to capitalize on the depth and breadth of clinical data within electronic health record (EHR) systems in order to develop next-generation sex-specific risk prediction scores for incident CVD. Methods: All individuals 30 years of age or older residing in Olmsted County, Minnesota on 1/1/2006 were identified. We developed and validated algorithms to define a variety of risk factors, thus building a comprehensive risk profile for each patient. Outcomes including myocardial infarction (MI), percutaneous intervention (PCI), coronary artery bypass graft (CABG), and CVD death were ascertained through 9/30/2017. Results: We identified 73,069 individuals without CVD (Table). We retrieved a total of 14,962,762 lab results; 14,534,466 diagnoses; 17,062,601 services/procedures; 1,236,998 outpatient prescriptions; 1,079,065 heart rate measurements; and 1,320,115 blood pressure measurements. The median number of blood pressure and heart rate measurements ascertained per individuals were 11 and 9, respectively. The five most prevalent conditions were: hypertension, hyperlipidemia, arthritis, depression, and cardiac arrhythmias. During follow-up 1,455 MIs, 1,581 PCI, 652 CABG, and 2,161 CVD-related deaths occurred. Conclusions: We developed a cohort with comprehensive risk profiles and follow-up for each patient. Using sophisticated machine learning approaches, this electronic cohort will be utilized to develop next-generation sex-specific CVD risk prediction scores. These approaches will allow us to address several challenges with use of EHR data including the ability to 1) deal with missing values, 2) assess and utilize a large number of variables without over-fitting, 3) allow non-linear relationships, and 4) use time-to-event data.

Background: The focus of most existing phenotyping algorithms based on electronic health record (EHR) data has been to accurately identify cases and non-cases of specific diseases. However, a more challenging task is to accurately identify disease incidence, as identifying the first occurrence of disease is more important for efficient and valid clinical and epidemiological research. Moreover, stroke is a challenging phenotype due to diagnosis difficulty and common miscoding. This task generally requires utilization of multiple types of EHR data (e.g., diagnoses and procedure codes, unstructured clinical notes) and a more robust algorithm integrating both natural language processing and machine learning. In this study, we developed and validated an EHR-based classifier to accurately identify stroke incidence among a cohort of atrial fibrillation (AF) patients Methods: We developed a stroke phenotyping algorithm using International Classification of Diseases, Ninth Revision (ICD-9) codes, Current Procedural Terminology (CPT) codes, and expert-provided keywords as model features. Structured data was extracted from Rochester Epidemiology Project (REP) database. Natural Language Processing (NLP) was used to extract and validate keyword occurrence in clinical notes. A window of ±30 days was considered when including/excluding keywords/codes into the input vector. Frequencies of keywords/codes were used as input feature sets for model training. Multiple competing models were trained using various combinations of feature sets and two machine learning algorithms: logistic regression and random forest. Training data were provided by two nurse abstractors and included validated stroke incidences from a previously established atrial fibrillation cohort. Precision, recall, and F-score of the algorithm were calculated to assess and compare model performances. Results: Among 4,914 patients with atrial fibrillation, 1,773 patients were screened. 3,141 patients had no stroke-related codes or keywords and were presumed to be free of stroke during follow-up. Among the screened patients, 740 had validated strokes and 1,033 did not have a stroke based on review of the EHR by trained nurse abstractors. The best performing stroke incidence phenotyping classifier utilized Keywords+ICD-9+CPT features using a random forest classifier, achieving a precision of 0.942, recall of 0.943, and F-score of 0.943. Conclusion: In conclusion, we developed and validated a stroke algorithm that performed well for identifying stroke incidence in an enriched population (AF cohort), which extends beyond the typical binary case/non-case stroke identification problem. Future work will involve testing the generalizability of this algorithm in a general population.

Purpose: Develop and evaluate a mammography intervention that provides hope about cancer prevention and treatment. Design: Pilot randomized controlled trial. Setting: Two communities on the Navajo Nation. Participants: Navajo women and support persons. Intervention: Both groups received standard care: one home visit discussing mammography pros/cons and barriers. The treatment group received an intervention based on Navajo language via an additional home visit with health education materials (written and oral) in English and Navajo, including a Navajo Cancer Glossary with a new descriptive phrase for cancer. Analysis: Between control and intervention conditions, we compared baseline sociodemographics; changes from baseline to 3 months on mammography completion and breast cancer literacy scores. Measures: (1) intervention feasibility; (2) self- and clinic-reported mammography screening completion; (3) breast cancer literacy. Results: A total of 25 participants were randomly assigned (13 treatment, 12 control), with 7 support persons in each arm. Mean age was 53 years, 90% had a high school degree or higher, 86% spoke Navajo and English. At 3 months, 44% had a clinically verified mammogram. Mammography completion was 57% among those with a support person and 27% among those without ( P = .14). Intervention women reported more breast cancer beliefs consistent with mammography ( P = .015). Conclusions: Increases in breast cancer beliefs consistent with mammography show promise. Findings highlight a need to tailor education materials to Navajo culture/language and focus on enhancing support.