Citations

Abstract Background: The utility of alpha-fetoprotein (AFP) for hepatocellular carcinoma (HCC) surveillance is controversial. We aimed to identify factors associated with elevated AFP and define the patients for whom AFP is effective for surveillance. Methods: Data from the NCI Early Detection Research Network phase II HCC biomarker study (233 early-stage HCC and 412 cirrhotic patients) were analyzed. We analyzed 110 early-stage HCC and 362 cirrhotic hepatitis C virus (HCV) patients for external validation. Sensitivity, specificity, and area under the ROC curve (AUC) for HCC were calculated. Results: HCV etiology, non-White race, and serum alanine transaminase (ALT) predicted elevated AFP in cirrhotics. Non-White race and ALT predicted elevated AFP in HCC patients. Higher AUC of AFP for HCC was noted in patients with HBV (0.85) and alcohol (0.84), whereas it was lower in patients with hepatitis C virus (HCV; 0.80) and nonviral/alcohol etiology (0.76). The AUC was higher in HCV patients with serum ALT ≤40 U/L than patients with serum ALT >40 U/L (0.91 vs. 0.75, P < 0.01). At 90% specificity, the sensitivity of AFP increased from 44% to 74% in Whites with HCV and from 50% to 85% in non-Whites with HCV. There was a trend toward higher AUC in HCV patients with serum ALT ≤40 U/L than those with serum ALT >40 U/L (0.79 vs. 0.69, P = 0.10) in the validation cohort. Conclusions: The satisfactory performance of AFP in HCV patients with normal ALT should be further validated. Impact: The AFP may serve as a valuable surveillance test in HCV patients with normal ALT. Cancer Epidemiol Biomarkers Prev; 26(7); 1085–92. ©2017 AACR.

Surgical transection of sensory nerves in the treatment of intractable neuropathic pain is a commonly performed procedure. At times these cases can be particularly challenging when encountering obese patients, when targeting deeper nerves or those with a variable branching pattern, or in the case of repeat operations. In this case series, the authors describe their experience with ultrasound-guided surgical instrument placement during transection of a saphenous nerve in the region of prior vascular surgery in 1 patient and in the lateral femoral cutaneous nerve in 2 obese patients. The authors also describe this novel technique and provide pilot data that suggests ultrasound-assisted surgery may allow for complex cases to be completed in an expedited fashion through smaller incisions.

Abstract Mutations in the EGFR gene or transcript fusion involving EML4-ALK result in oncogenic activation of these oncogenes driving lung adenocarcinoma growth in tumors carrying such an alteration. For lung adenocarcinoma with these genetic changes, small-molecule tyrosine kinase inhibitors have been highly effective at reducing tumor burden and improve the outcome of the patients. Unfortunately, drug resistance eventually develops in these tumors and challenges remain in controlling lung cancer recurrence after targeted therapy. To overcome recurrence, we initiated a prove-of-principle study to evaluate the feasibility of an integrated strategy utilizing genomic profiles of the tumor and patient-specific tumor xenografts derived (PDX) from biopsies for ex vivo evaluation of antitumor drugs to help guide personalized treatment of lung cancer in patients who have developed resistance to targeted therapy drugs. Our study has three main objectives. 1) Use tumor biopsies obtained at the time of recurrence for oncogene mutation and RNAseq analyses to identify molecular changes in oncogenes and gene pathways that can be potentially targeted. 2) Evaluate drug efficacy and optimize personalized therapy for each patient using PDX models. 3) Assess clinical feasibility and our experience using integrated approaches for lung cancer patients who failed targeted therapy. This study was approved by the Mayo Clinic Institutional Review Board (IRB) and utilizes both clinical and research biopsies. A dedicated nurse study coordinator reviews clinical patient list and history on weekly basis and informs the study team of each potential candidate patient. A total of 30 patients having ALK positive lung cancers have been identified and followed up from nearly 500 potentially ALK positive cases between April 2014 to Sept. 2015. Most patients were never smokers but six were former smokers and two were current smokers. Age at diagnoses ranged from 27-78 years (median = 61). Seven patients (23%) were 45 years or younger at the time of diagnosis. A total of 22 patients are currently being treated with crizotinib while eight are on ceritinib or alectinib. For each biopsy, tumor tissues are obtained using a 20 gauge needle, transferred on ice in preserving media and implanted within one hour into 6-8 week old NOD/SCID mice. Many patients have been on treatment for 2-3 years with stable disease so they do not require biopsy. Using a similar strategy, we also obtained biopsies from patients with EGFR gene mutations in their tumors and have progressed while on targeted therapy. A total of seven cases have been implanted. We will report our experiences in patient selection, clinical follow up, patient consent, PDX development, time from biopsy to tumor establishment, and the results of molecular analyses. Our study enabled us to gain new insights regarding the molecular changes associated with recurring tumors after they have failed targeted therapy as well as clinical experiences on how to utilize state-of-the art approaches and comprehensive genomic information to further improve cancer patient care upon disease progression. Acknowledgements: This work is supported in part by the Hillsberg Award from the National Foundation for Cancer Research and by the Biomarker Discovery Program at the Mayo Clinic Center for Individualized Medicine. Citation Format: Jin Jen, Aaron Mansfield, Patrick W. Eiken, Shawn Stoddard, Karlyn Pierson, Xiaonan Hou, Hong Zheng Ren, Julian Molina, Joanne Yi, Ping Yang. Integrated Approaches to Treating Lung Adenocarcinoma Resistant to Targeted Therapy. [abstract]. In: Proceedings of the AACR Special Conference: Patient-Derived Cancer Models: Present and Future Applications from Basic Science to the Clinic; Feb 11-14, 2016; New Orleans, LA. Philadelphia (PA): AACR; Clin Cancer Res 2016;22(16_Suppl):Abstract nr B34.

Abstract This abstract was not presented at the symposium.

7 Background: Improved prognostic biomarkers are needed for localized prostate cancer. We undertook an unbiased large-scale analysis of genes associated with metastatic progression and validated the prognostic ability of the top candidate gene. Methods: Prostate cancer samples from prostatectomy patients were analyzed for gene expression using a clinical-grade, high-density Affymetrix GeneChip platform, encompassing >1 million genomic loci and assessed in a CLIA-certified laboratory. Nomination of prognostic candidate genes was performed on a discovery cohort (n=545) and validated on 3 independent cohorts (n=463). Multivariate analyses were performed for the primary endpoint of metastasis. The top prostate-specific gene was further evaluated in 208 additional tumor samples with a novel RNA in-situ hybridization (ISH) assay and in urine samples from 230 patients using PCR. Results: Of all known genes, the long noncoding RNA SChLAP1 ranked first for elevated expression in patients with metastatic progression by receiver-operator-curve analyses. Validation in three independent cohorts confirmed the prognostic value of SChLAP1. On multivariate modeling, SChLAP1 expression independently predicted metastasis within 10 years (odds ratio (OR) = 2.45, 95% confidence interval (CI) 1.70 – 3.53), death within 10 years (OR = 1.93, 95% CI 1.31 – 2.85), and biochemical recurrence within 5 years (OR = 1.76, 95% CI 1.28 – 2.41) with ORs comparable to Gleason score. Evaluation of SChLAP1 expression by RNA ISH confirmed a significant association with disease recurrence (OR = 1.99, 95% CI 1.06 – 3.73). Evaluation of urine SChLAP1 levels demonstrated increased expression in patients at higher risk for disease progression. Conclusions: We perform the largest high-throughput, unbiased study of prostate cancer prognostic biomarkers to date and discover SChLAP1 as a top gene predictive of metastatic progression. We validate SChLAP1 extensively with a clinical-grade assay. We show feasibility of a RNA ISH assay and a non-invasive urine test for SChLAP1. Our results, spanning 1,446 patients from 6 independent patient cohorts, suggest that SChLAP1 represents a very promising biomarker for aggressive clinical course.

29 Background: Better biomarkers are needed in prostate cancer (PCa) to predict disease recurrence and guide optimal therapy. We investigated whether genes associated with a highly tumorigenic, drug resistant, progenitor cancer phenotype impact PCa biology and clinical outcomes in localized disease. Methods: Genes associated with self-renewal, drug resistance, and tumorigenicity were analyzed by qRT-PCR on PCa mRNA from radical prostatectomy (RP) specimens (+/- disease recurrence). Wilcoxon rank sum two-sample test, multivariable recursive partitioning, and bootstrap internal validation measured and confirmed associations with recurrence. Further validation was conducted in external cohorts and in-silico, as well as in vitro and in vivo using siRNA knockdown and lentiviral overexpression to determined the effect of gene expression on PCa proliferation, invasion and tumor growth. Results: Four candidate genes were differentially expressed in PCa recurrence, and of these, low AXIN2 expression was internally validated. Validation in external cohorts demonstrated low AXIN2 expression was associated with more aggressive prostate cancer and was independently associated with biochemical recurrence (BCR) and metastasis-free survival (MFS) after RP. In vitro, low AXIN2 expression was associated with a cancer stem-like cell-surface signature, and siRNA knockdown of AXIN2 resulted in significantly greater invasiveness. Conversely, ectopic overexpression of AXIN2 significantly reduced cell proliferation and tumor growth in mice. Conclusions: Low AXIN2 expression was associated with PCa recurrence after RP in our test population as well as in external validation cohorts. AXIN2 expression levels in PCa cells significantly impacted invasiveness, proliferation and tumor growth. AXIN2 represents a putative biomarker and potential therapeutic target in early prostate cancer.

389 Background: Venous thromboembolism (VTE) has been reported in approximately 5-7% of patients undergoing radical cystectomy (RC). While extended-duration pharmacologic prophylaxis (EDPP) has been investigated following surgery for a variety of malignancies, limited data exist in bladder cancer. Herein, we evaluated the efficacy and safety of EDPP after RC. Methods: We instituted a change in our clinical practice beginning in May 2014 such that patients undergoing RC were prescribed 30 days of enoxaparin at discharge. We recorded symptomatic VTE and lymphocele rates within 30 days of RC among patients treated from 5/14-6/15, and compared these outcomes to the cohort of all patients who underwent RC at our institution in the year prior to EDPP implementation. Patients in both groups received subcutaneous unfractionated heparin and mechanical prophylaxis during hospitalization. Patients with a history of VTE prior to surgery (n = 24) were excluded from study. Unadjusted descriptive statistics and univariate analyses were performed using the Pearson or Fisher chi-square test for categorical variables and Wilcoxon rank-sum test for continuous variables. Results: In total, 58 patients who received EDPP and 82 patients who had not received EDPP after RC were included for analysis. Baseline clinicopathologic demographics were similar between the cohorts. We found that only 1 patient (1.9%) discharged with EDPP was diagnosed with a VTE within 30 days of RC, compared to 5 (6.1%) who had not received EDPP. Mean time to VTE was 18.0 days after RC (range 9-28 days). Events consisted of DVT alone (n = 2), DVT and PE (n = 2), and PE alone (n = 2). The odds ratio for VTE in the absence of EDPP was 3.31 (95% CI 0.38, 29.2). Overall, 3 patients developed a symptomatic lymphocele within 30 days of RC: 1 (1.9%) who received EDPP and 2 (2.4%) who had not (p = 0.84). No patient in either cohort was rehospitalized for bleeding complications. Conclusions: Our initial experience suggests that EDPP was associated with a lower rate of VTE following RC, and does not increase the risks of bleeding or symptomatic lymphocele. Future evaluation in a larger-scale prospective clinical trial setting is needed to confirm the benefit of EDPP in RC patients.