Validity of self-reported diseases from health surveys: comparisons with registry data in Denmark

Background

The validity of self-reported disease prevalence estimates in health surveys may be low when compared to data from medical records in administrative registers. Such discrepancies reflect a low content validity of the survey question, which may ultimately compromise the application of these survey data for public health purposes. The aim of the present study was to examine the agreement of self-reports of seven diseases with data from administrative registers, both overall and by sociodemographic characteristics.

Methods

Prevalence estimates of self-reported current and/or previous diabetes, asthma, rheumatoid arthritis, osteoporosis, myocardial infarction, apoplexy, and cancer, respectively, were derived from the Danish National Health Survey in 2017 (n = 183,372 adults aged ≥16 years). Individual-level data were linked to registry data on the same diseases. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), kappa, and total agreement between self-reported and registry-documented prevalence estimates were examined.

Results

For all included diseases, the specificity was >92%, and the sensitivity varied between 59% (cancer) and 95% (diabetes). NPV was >94% for all diseases and PPV varied between 13% (rheumatoid arthritis) and 93% (cancer). Total agreement varied between 91 % (asthma) and 99% (diabetes), whereas kappa was lowest for rheumatoid arthritis (0.21) and highest for diabetes (0.88). Sociodemographic variables were significantly associated with total agreement with sex, age, and educational level exhibiting the strongest associations.

Conclusions

Overall, total agreement, specificity, and NPV between self-reported and registry-documented disease prevalence estimates are high, but PPV and kappa vary greatly between diseases. The latter findings reflect a low content validity of the applied survey question for specific diseases. This should be taken into account when interpreting similar results from surveys.

Key messages

• The validity of self-reported disease prevalence estimates may be low when compared to data from medical records. We found positive predictive values and kappa to vary greatly between diseases.

• Future studies should aim at designing survey questions properly in order to ensure a high content validity of the applied question.

Combination of type I and type II MET tyrosine kinase inhibitors as therapeutic approach to prevent resistance

MET targeted therapies are clinically effective in MET amplified and MET exon 14 deletion mutant (METex14) non-small cell lung cancers (NSCLC) but their efficacy is limited by the development of drug resistance. Structurally distinct MET tyrosine kinase inhibitors (TKIs) (type I/II) have been developed or are under clinical evaluation, which may overcome MET mediated drug resistance mechanisms. In this study, we assess secondary MET mutations likely to emerge in response to treatment with single-agent or combinations of type I/type II MET TKIs using TPR-MET transformed Ba/F3 cell mutagenesis assays. We found that these inhibitors gave rise to distinct secondary MET mutant profiles. However, a combination of type I/II TKI inhibitors (capmatinib and merestinib) yielded no resistant clones in vitro. The combination of capmatinib/merestinib was evaluated in vivo and led to a significant reduction in tumor outgrowth compared to either MET inhibitor alone. Our findings demonstrate in vitro and in vivo that a simultaneous treatment with a type I and type II MET TKI may be a clinically viable approach to delay and/or diminish the emergence of on target MET mediated drug resistance mutations.

Validation of ctDNA Quality Control Materials Through a Precompetitive Collaboration of the Foundation for the National Institutes of Health

We report the results from a Foundation for the National Institutes of Health Biomarkers Consortium project to address the absence of well-validated quality control materials (QCMs) for circulating tumor DNA (ctDNA) testing. This absence is considered a cause of variance and inconsistencies in translating ctDNA results into clinical actions.

METHODS

In this phase I study, QCMs with 14 clinically relevant mutations representing single nucleotide variants, insertions or deletions (indels), translocations, and copy number variants were sourced from three commercial manufacturers with variant allele frequencies (VAFs) of 5%, 2.5%, 1%, 0.1%, and 0%. Four laboratories tested samples in quadruplicate using two allele-specific droplet digital polymerase chain reaction and three (amplicon and hybrid capture) next-generation sequencing (NGS) panels.

RESULTS

The two droplet digital polymerase chain reaction assays reported VAF values very close to the manufacturers' claimed concentrations for all QCMs. NGS assays reported most single nucleotide variants and indels, but not translocations, close to the expected VAF values. Notably, two NGS assays reported lower VAF than expected for all translocations in all QCM mixtures, possibly related to technical challenges detecting these variants. The ability to call ERBB2 copy number amplifications varied across assays. All three QCMs provided valuable insight into assay precision. Each assay across all variant types demonstrated dropouts at 0.1%, suggesting that the QCM can serve for testing of an assay's limit of detection with confidence claims for specific variants.

CONCLUSION

These results support the utility of the QCM in testing ctDNA assay analytical performance. However, unique designs and manufacturing methods for the QCM, and variations in a laboratory's testing configuration, may require testing of multiple QCMs to find the best reagents for accurate result interpretation.

Plasma ctDNA Response Is an Early Marker of Treatment Effect in Advanced NSCLC

Plasma circulating tumor DNA (ctDNA) analysis is routine for genotyping of advanced non-small-cell lung cancer (NSCLC); however, early response assessment using plasma ctDNA has yet to be well characterized.

MATERIALS AND METHODS

Patients with advanced EGFR-mutant NSCLC across three phase I NCI osimertinib combination trials were analyzed in this study, and an institutional cohort of patients with KRAS-, EGFR-, and BRAF-mutant advanced NSCLC receiving systemic treatment was used for validation. Plasma was collected before treatment initiation and serially before each cycle of therapy, and key driver mutations in ctDNA were characterized by droplet digital polymerase chain reaction. Timing of plasma versus imaging response was compared in a separate cohort of patients with EGFR-mutant NSCLC treated with osimertinib. Across cohorts, we also studied ctDNA variability before treatment start.

RESULTS

In the NCI cohort, 14/16 (87.5%) patients exhibited ≥ 90% decrease in mutation abundance by the first on-treatment timepoint (20-28 days from treatment start) with minimal subsequent change. Similarly, 47/56 (83.9%) patients with any decrease in the institutional cohort demonstrated ≥ 90% decrease in mutation abundance by the first follow-up draw (7-30 days from treatment start). All 16 patients in the imaging cohort with radiographic partial response showed best plasma response within one cycle, preceding best radiographic response by a median of 24 weeks (range: 3-147 weeks). Variability in ctDNA levels before treatment start was observed.

CONCLUSION

Plasma ctDNA response is an early phenomenon, with the majority of change detectable within the first cycle of therapy. These kinetics may offer an opportunity for early insight into treatment effect before standard imaging timepoints.

Dynamic single-cell RNA sequencing identifies immunotherapy persister cells following PD-1 blockade

Resistance to oncogene-targeted therapies involves discrete drug-tolerant persister cells, originally discovered through in vitro assays. Whether a similar phenomenon limits efficacy of programmed cell death 1 (PD-1) blockade is poorly understood. Here, we performed dynamic single-cell RNA-Seq of murine organotypic tumor spheroids undergoing PD-1 blockade, identifying a discrete subpopulation of immunotherapy persister cells (IPCs) that resisted CD8+ T cell-mediated killing. These cells expressed Snai1 and stem cell antigen 1 (Sca-1) and exhibited hybrid epithelial-mesenchymal features characteristic of a stem cell-like state. IPCs were expanded by IL-6 but were vulnerable to TNF-α-induced cytotoxicity, relying on baculoviral IAP repeat-containing protein 2 (Birc2) and Birc3 as survival factors. Combining PD-1 blockade with Birc2/3 antagonism in mice reduced IPCs and enhanced tumor cell killing in vivo, resulting in durable responsiveness that matched TNF cytotoxicity thresholds in vitro. Together, these data demonstrate the power of high-resolution functional ex vivo profiling to uncover fundamental mechanisms of immune escape from durable anti-PD-1 responses, while identifying IPCs as a cancer cell subpopulation targetable by specific therapeutic combinations.

Concurrent osimertinib plus gefitinib for first-line treatment of EGFR-mutated non-small cell lung cancer (NSCLC)

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Background: First-line treatment with an EGFR tyrosine kinase inhibitor (TKI) is standard of care for patients (pts) with EGFR-mutated NSCLC. The EGFR TKI osimertinib is active against the acquired gefitinib-resistant mutation EGFR T790M, as is gefitinib against the osimertinib-resistant EGFR C797S. Preclinical evidence suggests dual EGFR inhibition with gefitinib + osimertinib may delay emergence of acquired resistance. Methods: This ongoing phase I/II study enrolled pts with stage IV EGFR-mutated (L858R or del19) NSCLC, without prior therapy for metastatic disease. Treatment in dose escalation (n = 6): concurrent osimertinib 40 mg or 80 mg + gefitinib 250 mg daily. In dose expansion (n = 21): osimertinib + gefitinib at the maximum tolerated dose (MTD). Prior to protocol amendment 6 pts received alternating monthly cycles of TKI monotherapy and were excluded from this analysis. The primary endpoints in the dose escalation and expansion phases were, respectively, identification of the MTD and feasibility, defined as receipt of combination therapy for ≥ 6 four-week cycles. Secondary endpoints included overall response rate (ORR), survival outcomes, plasma EGFR mutation clearance (cell free DNA by droplet digital PCR (ddPCR)), and mechanisms of acquired resistance. Results: From May 2017 to July 2019 27 pts were enrolled and evaluable for the primary endpoints. The MTD was osimertinib 80 mg plus gefitinib 250 mg orally daily. In feasibility analysis, 81.5% completed ≥6 cycles combination therapy (1 pt discontinued for progression, 4 for toxicity). The ORR was 85.2% (95% CI 67.5%-94.1%). Best response: 85.2% partial response, 14.8% stable disease. The most common treatment-related adverse effects (TRAEs) (% any grade, % grade 3) were rash (96.3%, 3.7%), diarrhea (85.2%, 11.1%) and dry skin (70.4%, 0%). Plasma ddPCR (n = 25 pts) detected the driver EGFR mutation at baseline in 68% of pts. In these pts, plasma EGFR cleared to undetectable at 2 weeks treatment in 82.4%. At 14.8 months median follow up the median progression free survival was not yet reached. Conclusions: Combination therapy with osimertinib and gefitinib is tolerable for first-line treatment of EGFR-mutated NSCLC and resulted in rapid plasma clearance of the EGFR mutation. The observed ORR is consistent with previously reported first-line response rates to osimertinib. Analysis of survival outcomes and acquired resistance mechanisms are pending data maturity and will facilitate understanding of the role of first-line dual EGFR TKI therapy for this pt population. Clinical trial information: NCT03122717 .

EGFR-Mutated Lung Cancers Resistant to Osimertinib through EGFR C797S Respond to First-Generation Reversible EGFR Inhibitors but Eventually Acquire EGFR T790M/C797S in Preclinical Models and Clinical Samples

INTRODUCTION

Osimertinib is approved for advanced EGFR-mutated NSCLC, and identification of on-target mechanisms of resistance (i.e., EGFR C797S) to this third-generation EGFR inhibitor are evolving. Whether durable control of subsequently osimertinib-resistant NSCLC with the EGFR-sensitizing mutation (SM)/C797S is possible with first-generation EGFR inhibitors (such as gefitinib or erlotinib) remains underreported, as does the resultant acquired resistance profile.

METHODS

We used N-ethyl-N-nitrosourea mutagenesis to determine the profile of EGFR SM/C797S preclinical models exposed to reversible EGFR inhibitors. In addition, we retrospectively probed a case of EGFR SM lung adenocarcinoma treated with first-line osimertinib, followed by second-line erlotinib in the setting of EGFR SM/C797S.

RESULTS

Use of N-ethyl-N-nitrosourea mutagenesis against the background of EGFR L858R/C797S in conjunction with administration of gefitinib revealed preferential outgrowth of cells with EGFR L858R/T790M/C797S. A patient with EGFR delE746_T751insV NSCLC was treated with osimertinib with sustained response for 10 months before acquiring EGFR C797S. The patient was subsequently treated with erlotinib, with response for a period of 4 months, but disease progression ensued. Liquid biopsy disclosed EGFR delE746_T751insV with T790M and C797S present in cis.

CONCLUSION

EGFR SM NSCLC can acquire resistance to osimertinib through development of the EGFR C797S mutation. In this clinical scenario, the tumor may respond transiently to reversible first-generation EGFR inhibitors (gefitinib or erlotinib), but evolving mechanisms of on-target resistance-in clinical specimens and preclinical systems-indicate that EGFR C797S along with EGFR T790M can evolve. This report adds to the growing understanding of tumor evolution or adaptability to sequential EGFR inhibition and augments support for exploring combination therapies to delay or prevent on-target resistance.

Abstract 452: Salivary HPV cell free DNA levels predict locoregional disease burden and response in oropharyngeal cancer

Purpose: The human papillomavirus (HPV) is linked to the majority of oropharyngeal squamous cell carcinomas (OPSCC). We have previously shown that tumor-derived HPV cell-free (cf)DNA can be detected and quantified in circulation with high sensitivity and specificity using droplet digital (dd)PCR1. Further, we have shown that plasma cfDNA levels correlate with disease burden and indicate treatment response in advanced OPSCC. In this study we pair plasma with salivary HPV cfDNA to understand its clinical application in monitoring locoregional spread of disease.

Methods: We present a proof-of-concept prospective observational cohort of recurrent, metastatic (R/M) HPV+ OPSCC patients treated with standard systemic therapies or on active surveillance. We utilized ultrasensitive ddPCR to identify and quantify both plasma and salivary HPV cfDNA (subtypes 16, 18, 31, 33 and 45) at multiple time points. Salivary HPV cfDNA was normalized to total DNA concentration as measured by fluorometric quantification. We then compared matched plasma and normalized salivary HPV cfDNA concentrations at various timepoints with clinical parameters, such as tumor burden and therapeutic response.

Results: Clinicopathologic data from 15 R/M patients revealed a male cohort with a median age of 57 at diagnosis. Five (33%) were on immunotherapy and 6 (40%) on standard chemotherapy during the study period (3 months). Salivary HPV cfDNA was detected in 13/15 (87%) samples (range 0-729 copies/mL) in at least one timepoint during the study (plasma cfDNA was detected in 12/15 or 80% of the cohort, range 0-12,949 copies/mL). All patients with measurable locoregional (LR) disease had detectable salivary cfDNA. While matched plasma and salivary cfDNA levels showed no correlation among individual patients, plasma cfDNA levels correlated with site of disease (LR, pulmonary or extra-pulmonary) (p < 0.001), while median salivary cfDNA levels strongly correlated with LR tumor burden (R = 0.81, p < 0.001). Salivary cfDNA levels declined by 80% of their baseline value within a median of 6.5 days among all patients with LR disease experiencing a response to treatment.

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Conclusion: Our results suggest that high sensitivity salivary HPV cfDNA levels correlate with locoregional disease burden and can be an early indicator of locoregional treatment response, while our prior work has supported the role of plasma HPV cfDNA levels in monitoring metastatic disease. Evaluating paired plasma and salivary HPV cfDNA levels in a curative HPV OPSCC population is underway to further validate their prognostic and predictive potential.

1Hanna GJ, Supplee JG, Kuang Y, Mahmood U, Lau CJ, Haddad RI, et al. Plasma HPV cell-free DNA monitoring in advanced HPV-associated oropharyngeal cancer. Ann Oncol. 2018;29:1980–6.

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Citation Format: Glenn J. Hanna, Christie J. Lau, Umair Mahmood, Robert I. Haddad, Cloud P. Paweletz, Pasi A. Janne. Salivary HPV cell free DNA levels predict locoregional disease burden and response in oropharyngeal 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 452.

Salivary HPV DNA informs locoregional disease status in advanced HPV-associated oropharyngeal cancer

OBJECTIVES

Quantifying tumor DNA in tissue and circulating in blood permits high-quality molecular monitoring to detect and track cancer progression. Evaluating tumor DNA in both blood and saliva in human papillomavirus (HPV)-associated oropharyngeal cancer (OPC) could provide a non-invasive and clinically actionable method for real-time disease detection.

METHODS

We previously validated an ultrasensitive droplet-digital (dd)PCR assay targeting the dominant high-risk HPV subtypes causally linked to OPC. Here we enrolled an observational cohort to evaluate the predictive and prognostic potential of paired plasma-salivary tumor DNA among 21 patients with advanced HPV+OPC.

RESULTS

In patients with recurrent, persistent locoregional (LR) disease, median baseline normalized salivary HPV DNA was 10.9 copies/ng total DNA, nearly 20x higher compared with those with distant disease only (p = 0.01). A cutoff of 5 copies/ng yielded 87% sensitivity and 67% specificity for accurately predicting LR disease. Total tumor burden among those with LR disease strongly correlated with salivary HPV DNA levels (R = 0.83, p = 0.02). The rise and fall of salivary HPV DNA predicted treatment failure and response, respectively, in all patients with LR disease, and predated imaging findings. Among paired salivary-plasma (cell-free) cfDNA samples, only higher plasma HPV cfDNA levels were associated with poor outcomes (p < 0.01), suggesting that each bodily fluid provides unique information about HPV disease status.

CONCLUSIONS

Salivary HPV DNA provides valuable information about tumor burden and predicts treatment response in advanced HPV+OPC. Paired blood-saliva samples could be used to monitor HPV DNA with broad applications to inform diagnosis, prognosis, and surveillance in HPV-associated diseases.

Osimertinib (Osi) plus necitumumab (Neci) in EGFR-mutant NSCLC: An ETCTN California cancer consortium phase I study

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Background: Osi (3rd gen EGFR TKI) has robust activity in 1st line EGFR mutant NSCLC and TKI resistant T790Mpos NSCLC but progressive disease (PD) occurs and outcomes with Osi alone are poor in T790Mneg, C797Xpos and EGFR exon 20 insertion (ins20) disease. This study examined the EGFR monoclonal antibody Neci with Osi in select settings of EGFR TKI resistance. Methods: Using a 3+3 design, Neci was examined in advanced EGFR mutant NSCLC at dose levels (DL) of 600 mg (DL1) & 800 mg (DL2) D1, D8 IV q21 days + Osi 80 mg qd. Four expansion cohorts (ExC; 18 each) included: A) T790Mneg PD on 1st/2nd gen TKI as last therapy, B) T790Mneg PD on 3rd gen TKI, C) T790Mpos PD on 3rd gen TKI, D) EGFR ex20ins PD on chemotherapy. Central T790M testing by ddPCR in ExC A-C. Additional studies performed include: NGS panel of > 400 genes, EGFR FISH, plasma for PK and serial EGFR ctDNA by ddPCR as exploratory analyses. Adverse events (AEs) graded (Gr) by CTCAEv5 with ORR and PFS by RECIST 1.1. Results: Dose escalation and ExC B completed accrual. In total 55 pts were evaluable (Table). 1 pt had DLT at DL2, Gr 3 sinus bradycardia. Drug related Gr 3 AEs were seen in 27% (15) of pts, mainly rash (7;13%). ctDNA showed decreased mutant allele frequency with therapy in all pts studied with detected EGFR at baseline, with complete plasma clearance in a pt with detectable C797S. Conclusions: The RP2D (Osi 80 mg qd and Neci 800 mg D1, D8 IV on q21d cycle) is feasible and tolerable. In ExC A,T790Mneg pts with 1st/2nd gen EGFR TKI as last treatment, using curtailed sampling, the pre-specified efficacy signal was reached for Osi + Neci comparing favorably to Osi alone in analogous pts from the AURA trial. Clinical activity was also seen in EGFR-dependent resistance (T790Mpos C797Spos) after PD on 3rd gen TKI and in EGFR ins 20. Clinical trial information: NCT02496663. [Table: see text]

Dairy product intake in relation to glucose regulation indices and risk of type 2 diabetes

BACKGROUND AND AIM

A high intake of dairy has been linked to lower risk of type 2 diabetes (T2D). The relationship between dairy intake and glucose metabolism is still not well understood. The aim of this study was to investigate the relation between the intake of total dairy and dairy subgroups and T2D and measures of glucose metabolism.

METHODS AND RESULTS

A total of 5953 Danish men and women aged 30-60 years without baseline diabetes or cardiovascular diseases were included in this prospective analysis. The dairy intake at baseline was categorised into low-fat dairy, full-fat dairy, milk and milk products, cheese and fermented dairy. Fasting plasma glucose (FPG), 2-h plasma glucose (2hPG), HbA1c, insulin resistance (HOMA2-IR) and beta-cell function (HOMA2-B) were considered at 5-year follow-up. In the maximally-adjusted model (demographics, lifestyle factors, dietary factors and waist), cheese intake was inversely associated with 2hPG (β = -0.048, 95% CI -0.095; -0.001). Fermented dairy intake was inversely associated with FPG (β = -0.028, 95% CI -0.048; -0.008) and HbA1c (β = -0.016, 95% CI -0.030; -0.001). Total dairy intake and the dairy subgroups were not related to HOMA-IR and HOMA-B in the maximally-adjusted model. Furthermore, there was no significant association between intake of total dairy or any of the dairy subgroups and incidence of T2D.

CONCLUSION

Our data suggest a modest beneficial effect of cheese and fermented dairy on glucose regulation measures; however, this did not translate into a significant association with incident T2D.