Citations

TPS9077 Background: ALCHEMIST (Adjuvant Lung Cancer Enrichment Marker Identification and Sequencing Trial) is a clinical trial platform of the National Cancer Institute that offers biomarker analysis for high-risk resected non-small cell lung cancer (NSCLC) to support randomized trials of novel adjuvant therapies within the National Clinical Trials Network (NCTN). EA5142, a trial of adjuvant nivolumab for patients (pts) without EGFR / ALK alterations, has completed enrollment. Given the survival benefit seen with 1st-line chemo-immunotherapy (chemo-IO) for advanced NSCLC without EGFR / ALK alterations, there was compelling rationale for the launch of a trial offering concurrent immunotherapy with adjuvant chemo. Here we report updated enrollment to ALCHEMIST as of Jan 14, 2020. Methods: ALCHEMIST includes a screening trial (A151216, 5362 registered) that enrolls pts with completely resected clinical stage IB (≥4 cm)–IIIA (per AJCC 7) NSCLC. Tissue and blood are collected, biomarker testing includes EGFR sequencing, ALK FISH and PD-L1 IHC. 733 active sites are enrolling across the NCTN. Pts with EGFR mutations may enroll to adjuvant erlotinib vs observation (A081105, 352 randomized); those with ALK fusions may enroll to adjuvant crizotinib vs observation (E4512, 99 randomized). A trial offering adjuvant nivolumab vs observation regardless of PD-L1 status (EA5142, 935 randomized) recently completed enrollment. To support ongoing investigation of adjuvant immunotherapy, ALCHEMIST is adding A081801 (opens spring 2020). Pts will be randomized to one of 3 arms: chemo-IO with pembrolizumab during and after chemo vs sequential chemo followed by pembrolizumab vs chemo alone. Pts with pathological N2 nodes are eligible and can undergo postoperative radiotherapy after completing chemo. Pts are eligible if enrolled to A151216, negative for EGFR and ALK alterations, and with PD-L1 testing completed (required for stratification). Local testing for EGFR, ALK and PD-L1 will be accepted for enrollment; central testing will not delay randomization. Pts may not have received any therapy except surgery for the lung cancer and must be age >18, Eastern Cooperative Oncology Group performance status 0-1, have no active autoimmune disease requiring systemic treatment within 2 years, must not be pregnant or nursing, have no active second malignancy within 3 years and meet standard organ function values. By building off the ongoing ALCHEMIST platform, we hope to facilitate rapid enrollment to A081801 across participating NCTN sites. Clinical trial information: NCT02194738.

6072 Background: Effective screening tests for ovarian cancer (OC) are lacking; most cases present at advanced stage and portend poor prognosis. DNA methylation is an early event in carcinogenesis and can be detected in blood plasma samples from cancer patients. In DNA extracted from tissues, we first discovered, then validated discriminant methylated DNA marker (MDM) candidates for OC and subsequently tested independent plasma from women with and without OC. Methods: For discovery, DNA from 67 frozen tissues (18 high grade serous (HGS), 18 endometrioid, 15 clear cell (CC), 6 mucinous OCs; 10 benign fallopian tube epithelium (FT); and 19 buffy coats from cancer-free women underwent reduced representation bisulfite sequencing (RRBS) to identify MDMs associated with OC. Candidate MDM selection was based on receiver operating characteristic (ROC) discrimination, methylation fold change, and low background methylation among controls. Blinded biological validation was performed using methylated specific PCR on DNA extracted from independent FFPE tissues from OCs (36 HGS, 22 endometrioid, 21 CC, and 14 mucinous) and 29 FT. Top performing MDMs in tissue were tested using long-probe quantitative amplified signal assays in independent pre-treatment plasma samples from women newly-diagnosed with OC and population-sampled healthy women. A random forest modeling analysis was performed to generate predictive probability of disease; results were 500-fold in silico cross-validated. Results: After RRBS discovery and biological validation, 33 MDMs showed marked methylation fold changes (10 to > 1000) across all OC histologies vs FT. The top 11 MDMs ( GPRIN1, CDO1, SRC, SIM2, AGRN, FAIM2, CELF2, DSCR6, GYPC, CAPN2, BCAT1) were tested on plasma from 91 women with OC (76 (84%) HGS) and 91 without OC; the cross-validated 11-MDM panel highly discriminated OC from controls (96% (95%CI 89-99%) specificity; 79% (69-87%) sensitivity, and AUC 0.91 (0.86 - 0.96)). Among HGS, the panel correctly identified 83%, including 5/6 stage I/II, and the majority of other subtypes (Table). Conclusions: Whole methylome sequencing, stringent filtering criteria, and biological validation yielded outstanding candidate MDMs for OC that performed with promisingly high sensitivity and specificity in plasma. Larger plasma-based OC MDM testing studies, with larger numbers of non-HGS histologies are warranted. [Table: see text]

e16705 Background: The prevalence of pancreatic neuroendocrine tumors (PNETs) has increased in the last decade. Despite being clinically asymptomatic PNETs can be biologically aggressive. There is currently no reliable non-invasive diagnostic biomarker for PNETs. In this study we aimed to identify and validate methylated DNA marker (MDM) candidates that differentiate PNET from normal pancreas. Methods: For discovery, reduced representation bisulfite sequencing (RRBS) was performed on DNA extracted from frozen normal pancreas (n = 13) and PNET (n = 51) tissues. Area under the receiver operator characteristic curve (AUC), fold-change, and p-value criteria selected candidates MDMs for blinded validation in independent FFPE tissues from primary PNET (n = 67; solid = 50, cystic = 17), normal pancreas controls (n = 24), and normal buffy coat (n = 36) using methylation specific PCR. MDM distributions in primary PNETs were compared to primary lung (n = 36) and small bowel (n = 36) NETs and metastatic PNET tissue (n = 25). The discrimination accuracy of candidate markers was summarized as the AUC with corresponding 95% confidence intervals (CI). Results: From the RRBS discovery, 31 candidate MDMs were selected for validation. Four MDMs ( SRRM3, HCN2, SPTBN4 and TMC6) achieved individual AUCs ≥0.95 in the validation set (Table). These MDMs were similarly discriminant in metastatic PNET tissue and in primary lung and small bowel NETs. Three out of these 4 MDMs perfectly differentiated PNET tissue from buffy coat with AUC of 1 and may be ideally suited for further development of a blood-based assay. Conclusions: We identified and validated novel MDMs in tissue that discriminate PNETs from controls with normal pancreas and buffy coat with high accuracy. These MDMs also differentiated metastatic PNETs from normal pancreas tissue. Further exploration of these candidate tissue MDMs in plasma can potentially guide diagnosis and management of PNETs. Funding: P30DK084567. [Table: see text]

4088 Background: Methylated DNA markers (MDMs) are broadly informative for early detection of colorectal cancer (CRC) but have not been extensively studied for post-treatment surveillance and disease monitoring. We aimed to assess the feasibility of novel CRC-associated MDMs for detection of distant recurrent CRC (rCRC) in plasma. Methods: A panel of 13 MDMs previously identified to be discriminant for primary CRC was selected. In a cross-sectional analysis of plasma samples, MDMs were assayed blindly (by target enrichment long-probe quantitative amplified signal assay) from 160 age/sex-balanced patients (60 healthy controls, 60 with resected CRC and no evidence of disease (NED), and 40 rCRC after primary tumor resection). Plasma-derived carcinoembryonic antigen (CEA) was measured on all patients. Random forest modeling was used to derive a prediction algorithm of MDMs (with and without CEA) for the endpoint of rCRC relative to healthy controls. The accuracy of the algorithm was summarized as sensitivity, specificity, and area under the receiver operating characteristic curve (AUC) with 95% confidence intervals (CI) in the test set. Results: Median patient age was 55 (interquartile range: 49-64) years. As shown in the Table below, a single MDM with the highest AUC was significantly better than CEA ( p= 0.02). On cross validation, CEA provided no additional improvement to the performance of the panel of 13 MDMs ( p= 0.2). The cross-validated panel of MDMs detected rCRC liver metastases with 96% (79-100%) sensitivity, lung metastases with 78% (40-97%) sensitivity, and peritoneal/nodal metastases with 57% (18-90%) sensitivity. Lesions with Response Evaluation Criteria in Solid Tumors sum > 4 cm were detected with 94% (73-100%) sensitivity and ≤4 cm with 78% (52-94%) sensitivity. Conclusions: Novel MDMs in plasma detect rCRC with promising accuracy. The clinical utility of MDMs for non-invasive post-treatment surveillance and treatment monitoring in CRC warrants further evaluation in longitudinal studies with sufficient follow-up to exclude sub-clinical recurrence in those with NED. [Table: see text]

1506 Background: Hereditary breast and ovarian cancer (HBOC) is preventable when genetic risk is identified. We aimed to test whether pre and/or post-test genetic counseling is needed to optimally deliver online accessible genetic testing. Methods: MAGENTA (Making GENetic Testing Accessible) is a four-arm non-inferiority trial evaluating electronic genetic education and results delivery alone or combined with pre-test only, or post-test only telephone genetic counseling compared to mandatory pre- and post-test counseling (control arm) in women at risk of HBOC (NCT02993068). Regardless of assigned arm, all subjects with a pathogenic mutation received post-test telephone counseling. All subjects were enrolled electronically as part of either a family history cohort (FHC) or a cascade cohort (CC, known familial mutation). The primary outcome was cancer risk distress at 3 months and the trial was powered for the FHC. Secondary outcomes included completion of testing (i.e., received results), anxiety, depression, quality of life, and decisional regret, all measured by standardized scales. Results: Enrollment is complete and a total of 3,822 participants were randomized, 3,111 in FHC and 711 in CC. Participants were enrolled from all 50 states, but most were white/non-Hispanic (88%). Among participants that completed genetic testing, 173 (7.2%) had a mutation in a breast or ovarian cancer gene, with 114 (5.7%) of FHC and 59 (14.2%) of CC. In the primary intention-to-treat analysis of FHC, each of the three experimental arms was non-inferior to the control arm for distress at 3 months (p < 0.025/3 = 0.0083). In the CC, no and pre-test only counseling were also non-inferior (p < 0.025/3 = 0.0083). Distress was lowest in the arm with neither pre nor post-test counseling. Overall, 318 (18%) participants had very high distress at three month follow-up, and this rate was not significantly different across arms. Anxiety, depression and decisional regret did not have statistically significant differences across arms at follow-up. Test completion was highest in the no counseling arm (86.4%) and lowest in the control arm (60.6%). Conclusions: Electronic genetic education and results release without genetic counseling was non-inferior with regard to patient distress and was associated with higher test completion and lower distress. These results support use of a genetic testing paradigm providing individualized genetic counseling only for patients with positive test results. Clinical trial information: NCT02993068.

1087 Background: OlympiAD (NCT02000622) demonstrated the benefit of olaparib over standard of care in patients (pts) with HER2-negative (HER2-) metastatic breast cancer (MBC) and germline BRCA mutations (gBRCAm). LUCY (NCT03286842) aimed to provide additional data on the real-world effectiveness and safety of olaparib monotherapy in this setting. Methods: This Phase IIIb, open-label, single-arm study of olaparib 300 mg twice-daily, enrolled pts with HER2- gBRCAm MBC who had received a taxane and/or anthracycline in the (neo)adjuvant/metastatic setting, and ≤2 lines of chemotherapy for MBC. Hormone receptor-positive (HR+) pts had progressed on prior endocrine therapy (ET), and further ET was considered unsuitable. Primary endpoint: investigator-defined progression-free survival (PFS). Secondary endpoints: overall survival, time to first subsequent therapy or death (TFST), and investigator-assessed clinical response rate (CRR). The interim analysis was planned after 160 PFS events. Results: From Oct 2018-Sept 2019, 252 pts were enrolled (160 sites, 15 countries; mean age 46.2 [range 22-75] years; 73.4% ECOG PS 0). Median total treatment duration: 7.9 months (mo; range 0.2-20.0). Median PFS: 8.1 mo (95% confidence interval [CI] 6.9, 8.7; 166 events [65.9%]). Clinical trial information: NCT03286842 . Median TFST: 9.7 mo (95% CI 8.7, 11.1). CRR: 48.6% (95% CI 42.2, 55.0). Adverse events (AEs) in >20% of pts (all grades): nausea, anemia, asthenia, vomiting, and fatigue. 24.6% of pts reported a grade ≥3 AE, including anemia (n=33 [13.1%]). 4.4% of pts had an AE leading to treatment discontinuation. Conclusions: Interim results in this real-world population of pts with HER2- gBRCAm MBC were consistent with the OlympiAD study, and support olaparib as a chemotherapy-free alternative treatment for pts with gBRCAm advanced BC. [Table: see text]

Abstract Objectives Crystal-storing histiocytosis (CSH) is rare in plasma cell dyscrasias, with only 3 cases reported in the setting of amyloid. No cases of crystal-negative histiocytosis coincident with multiple myeloma and amyloidosis have been reported previously. Methods A 58-year-old woman presented with pain due to destructive bone lesions and was found to have plasma cell myeloma (PCM) and marrow amyloid deposition associated with crystal-negative histiocytosis. Differential diagnoses included Langerhans cell histiocytosis, Erdheim-Chester disease, and Rosai Dorfman disease. BRAF mutations were negative, and there was no evidence of paraprotein crystals, arguing against typical CSH. Results The patient was treated with bortezomib, cyclophosphamide, and dexamethasone, and she subsequently underwent autologous stem cell transplant and ixazomib maintenance. She achieved complete remission with improvement of her symptoms and preserved remission after following up at 60 months. Conclusions We describe a case of crystal-negative histiocytosis associated with PCM. CSH is a rare disorder associated with paraprotein-producing conditions in which immunoglobulins aggregate as intracellular crystals in the lysosomes of organ-specific phagocytic macrophages. Light chain tropism in PCM can also lead to the development of amyloid deposition in organs and, in rare cases, is associated with light chain aggregation as intracellular crystals in macrophages.

Background: Long QT syndrome (LQTS) is a rare genetic disorder and a major preventable cause of sudden cardiac death in the young. A causal rare genetic variant with large effect size is identified in up to 80% of probands (genotype positive) and cascade family screening shows incomplete penetrance of genetic variants. Furthermore, a proportion of cases meeting diagnostic criteria for LQTS remain genetically elusive despite genetic testing of established genes (genotype negative). These observations raise the possibility that common genetic variants with small effect size contribute to the clinical picture of LQTS. This study aimed to characterize and quantify the contribution of common genetic variation to LQTS disease susceptibility. Methods: We conducted genome-wide association studies followed by transethnic meta-analysis in 1656 unrelated patients with LQTS of European or Japanese ancestry and 9890 controls to identify susceptibility single nucleotide polymorphisms. We estimated the common variant heritability of LQTS and tested the genetic correlation between LQTS susceptibility and other cardiac traits. Furthermore, we tested the aggregate effect of the 68 single nucleotide polymorphisms previously associated with the QT-interval in the general population using a polygenic risk score. Results: Genome-wide association analysis identified 3 loci associated with LQTS at genome-wide statistical significance ( P <5×10 −8 ) near NOS1AP , KCNQ1 , and KLF12 , and 1 missense variant in KCNE1 (p.Asp85Asn) at the suggestive threshold ( P <10 −6 ). Heritability analyses showed that ≈15% of variance in overall LQTS susceptibility was attributable to common genetic variation ( h2SNP 0.148; standard error 0.019). LQTS susceptibility showed a strong genome-wide genetic correlation with the QT-interval in the general population (r g =0.40; P =3.2×10 −3 ). The polygenic risk score comprising common variants previously associated with the QT-interval in the general population was greater in LQTS cases compared with controls ( P <10−13), and it is notable that, among patients with LQTS, this polygenic risk score was greater in patients who were genotype negative compared with those who were genotype positive ( P <0.005). Conclusions: This work establishes an important role for common genetic variation in susceptibility to LQTS. We demonstrate overlap between genetic control of the QT-interval in the general population and genetic factors contributing to LQTS susceptibility. Using polygenic risk score analyses aggregating common genetic variants that modulate the QT-interval in the general population, we provide evidence for a polygenic architecture in genotype negative LQTS.

Background: Patients with atrial fibrillation on oral anticoagulation (OAC) undergoing cardiac catheterization face risks for embolic and bleeding events, yet information on strategies to mitigate these risks in contemporary practice is lacking. Methods: We aimed to describe the clinical/procedural characteristics of a contemporary cohort of patients with atrial fibrillation on OAC who underwent cardiac catheterization. Use of bleeding avoidance strategies and bridging therapy were described and outcomes including death, stroke, and major bleeding at 30 days and 1 year were compared by OAC type. Results: Of 13 404 patients in the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation II Registry from 2013 to 2016, 741 underwent cardiac catheterization (139 with percutaneous coronary intervention) in the setting of OAC. The patients’ median age was 71, 61.8% were male, white (87.2%), had hypertension (83.7%), hyperlipidemia (72.1%), diabetes mellitus (31.6%), and chronic kidney disease (28.2%); 20.2% received warfarin while 79.8% received direct acting oral anticoagulant. One third of patients underwent radial artery access, and bivalirudin was used in 4.6%. Bridging therapy was used more often in patients on warfarin versus direct acting oral anticoagulant (16.7% versus10.0%). OAC was interrupted in 93.8% of patients. Patients on warfarin versus direct acting oral anticoagulant were equally likely to restart OAC (58.0% versus 60.7%), had similar use of antiplatelet therapy (44.0% versus 41.3%) after catheterization, and had similar rates of myocardial infarction and death at 1 year, but higher rates of major bleeding (43.3 versus 12.9 events/100 patient years) and stroke (4.9 versus 1.9 events/100 patient years). Conclusions: In a real-world registry of patients with atrial fibrillation undergoing cardiac catheterization, most cases are elective, performed by femoral access, with interruption of OAC. Bleeding avoidance strategies such as radial artery access and bivalirudin were used infrequently and use of bridging therapy was uncommon. Nearly 40% of patients did not restart OAC postprocedure, exposing patients to risk for stroke. Further research is necessary to optimize the management of patients with atrial fibrillation undergoing cardiac catheterization.