ABSTRACT
Background: Most patients with pancreatic cancer (PC) and biliary tract cancer (BTC) present with advanced disease. In confirmed cases, circulating tumour DNA (ctDNA) may be detected through liquid biopsy in 80-90%. Obtaining a diagnostic biopsy can be technically challenging, require complex invasive procedures and may not be feasible due to comorbidity. Reduction in capacity of aerosol generating diagnostic procedures in many healthcare systems due to COVID19 has highlighted the unmet need for simple, noninvasive diagnostic tools. We piloted the use of ctDNA to support the diagnostic pathway in patients with suspected cancer across 6 tumour types, here we present its use in PC/BTC. Methods: This single centre prospective cohort pilot trial was conducted at the Royal Marsden from June 2020 to August 2021. 16 patients were planned each in the PC and BTC cohorts. Eligibility included radiologically suspicious PC/BTC without histological diagnosis, patients with prior non-diagnostic biopsy and inaccessible tumours. Liquid biopsy for ctDNA was collected for plasma based next generation sequencing, using a custom 59 gene panel of common variants in PC/BTC tumours, including analysis for somatic, copy number and structural variants. Clonal haematopoiesis of indeterminate potential (CHIP) and germline variants were identified and subtracted. A molecular tumour board (MTB) reviewed results for interpretation and clinical context. Primary outcome was the proportion of patients with a ctDNA result consistent with a diagnosis of malignancy following MTB discussion. Results: 32 patients with suspected PC (n= 16) and BTC (n=16) were recruited. Baseline characteristics are shown in table. ctDNA was detected in 69% off, 23 patients had a subsequent biopsy. The sensitivity and specificity of ctDNA as a diagnostic tool was 80% (90% CI 49.3-96.3) and 100% (90% CI 36.8-100) for PC respectively, and 100% (90% CI 60.7-100) and 75% (90% CI 24.9- 98.7) for BTC respectively. There were 2 false negatives in the PC cohort subsequently diagnosed with PC, and 1 false positive in the BTC cohort subsequently diagnosed with oesophageal cancer. Conclusions: ctDNA can be used to support a diagnosis of cancer in patients with radiologically suspected PC/BTC. A blood first, tissue second strategy in the diagnosis of PC/BTC could improve diagnostic efficiency, speed, and add resilience to the current diagnostic pathway.
ABSTRACT
The ongoing pandemic of SARS-CoV-2 calls for rapid and cost-effective methods to accurately identify infected individuals. The vast majority of patient samples is assessed for viral RNA presence by RT-qPCR. Our biomedical research institute, in collaboration between partner hospitals and an accredited clinical diagnostic laboratory, established a diagnostic testing pipeline that has reported on more than 252,000 RT-qPCR results since its commencement at the beginning of April 2020. However, due to ongoing demand and competition for critical resources, alternative testing strategies were sought. In this work, we present a clinically-validated procedure for high-throughput SARSCoV-2 detection by RT-LAMP in 25 minutes that is robust, reliable, repeatable, sensitive, specific, and inexpensive © 2021. Buck MD et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited