Diagnosis of pancreaticobiliary malignancy by detection of minichromosome maintenance proteins in cytological specimens

Lead Research Organisation: University College London
Department Name: Medicine

Abstract

The diagnosis of pancreatic and bile duct cancer at an early stage of disease remains difficult and there are no established tests to screen patients at high-risk of developing these cancers such as those with chronic pancreatitis (20x increased risk) and primary sclerosing cholangitis (160x increased risk). Blood tests and scans are not usually accurate enough to confirm the presence of cancer so cells are usually obtained from the lining of a narrowed bile duct with a brush (brush cytology) to look for cancer under the microscope. Brush cytology however only detects cancer in 20-50% of cases which means that patients often have to undergo additional invasive procedures, leading to potential complications and delays in diagnosis. Better diagnostic tests are clearly needed.
The aim of this study is to test new potential markers called minichromosome maintenance proteins (mcm 2-7) which may improve the early detection of precancerous changes and cancers involving the bile duct, and thus enhance the longevity and quality of life of patients living with pancreatic and bile duct cancer. These proteins are necessary for DNA replication which is essential for all cancer cells to multiply and grow. We have shown that the levels of these proteins are increased in a wide variety of early and advanced cancers in comparison to benign tissues, and can be used as accurate diagnostic tests for cervical, oesophageal and bladder cancer.
We have recently completed a study of 102 patients which showed that Mcm 5 protein when detected in bile is more than three times better than brush cytology at detecting pancreatic and biliary tract cancer, with up to 80% of cancers correctly diagnosed. The accuracy if this test depends in part on how many cells there are available to test. Brush cytology contains many more cells than bile and we now have exciting early results indicating that when Mcm 5 is detected in brush cytology specimens, close to 100% of cancers may be detected. We therefore plan to confirm these results by studying this marker as part of a large multicentre study, including patients at high risk of developing pancreatic and bile duct cancer.

Technical Summary

The diagnosis of pancreatic and biliary tract cancer at an early stage of disease remains difficult and there are currently no established screening tests available, even in the high-risk groups of chronic pancreatitis (~20-fold increased risk of pancreatic cancer) and primary sclerosing cholangitis (~160-fold increased risk of biliary tract cancer). Biliary brush cytology is the standard method of sampling a biliary stricture but has a low sensitivity (20-50%) for the detection of malignancy. We have previously shown that minichromosome maintenance (MCM) replication proteins (Mcm2-7) are markers of dysplasia and have utilised these novel biomarkers of growth for the diagnosis of cervical and bladder cancer (Stoeber et al. Lancet 1999; Stoeber et al. JNCI 2002).

Following on from these data in other solid organ tumours, we reported in a proof of principle prospective, blinded, single-centre study of 102 patients that Mcm5 levels in bile, detected by a two site time resolved immunofluorometric test with europium as a label, were significantly more sensitive (66% vs. 20%, p=0.004) than brush cytology for the detection of malignancy, with a comparable positive predictive value (97% vs. 100%, p=ns) (Ayaru et al. Br J Cancer 2008). In the same study, we also showed that Mcm 2 and 5 proteins detected in biopsy specimens are dysregulated in pancreaticobiliary malignancy. The percentage of nuclei positive for Mcm2 was higher in malignant tissue (median 76.5%, range 42-92%) than in benign tissue (median 5%, range 0-33%; p 0.0005), with similar results for Mcm5.

The sensitivity of the Mcm 5 test depends in part on the cellularity of bile, which can be acellular in up to 30% of samples, so that the sensitivity of bile aspirate Mcm5 cannot be expected to reach 100%. In contrast, the cellularity of brush cytology is much greater than bile aspirates. In a preliminary study of 20 patients with indeterminate biliary strictures, the Mcm 5 assay, when applied to biliary brush cytology specimens (n=20), had a sensitivity of 100% and an accuracy of 89% for the detection of malignancy (Ayaru et al, unpublished). We aim to extend these exciting preliminary data in a much larger group of patients with suspected pancreaticobiliary malignancy as part of a multicentre study, and to determine if the level of Mcm5 detected in brush cytology and bile specimens can distinguish accurately between the diagnostically challenging subgroups of: a) chronic pancreatitis and pancreatic cancer, and b) primary sclerosing cholangitis and biliary tract cancer.

Publications

10 25 50

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Chapman MH (2009) Cholangiocarcinoma: improving biliary drainage with PDT. in Photodiagnosis and photodynamic therapy

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Pereira SP (2018) The endoscopist and malignant and non-malignant biliary obstruction. in Biochimica et biophysica acta. Molecular basis of disease

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Samkoe KS (2010) Imaging tumor variation in response to photodynamic therapy in pancreatic cancer xenograft models. in International journal of radiation oncology, biology, physics

 
Description All Party Parliamentary Group on Pancreatic Cancer
Geographic Reach National 
Policy Influence Type Participation in a national consultation
 
Description National guidelines on cholangiocarcinoma (Gut 2012)
Geographic Reach National 
Policy Influence Type Membership of a guidance committee
 
Description CRUK PhD Research Bursary
Amount £20,618 (GBP)
Organisation Cancer Research UK 
Sector Charity/Non Profit
Country United Kingdom
Start  
 
Description Diagnostic markers for biliary tract cancer
Amount £100,000 (GBP)
Organisation National Institute for Health Research 
Department NIHR Biomedical Research Centre
Sector Academic/University
Country United Kingdom
Start 10/2014 
End 10/2016
 
Description MRC EME Programme - Implementation of a three-biomarker urine panel in high-risk symptomatic patients to provide early diagnosis of pancreatic adenocarcinoma.
Amount £49,986 (GBP)
Funding ID 15/180/46 
Organisation Medical Research Council (MRC) 
Sector Academic/University
Country United Kingdom
Start 05/2017 
End 11/2017
 
Description NIHR Flexibility and Sustainability Fund
Amount £38,000 (GBP)
Organisation National Institute for Health Research 
Sector Public
Country United Kingdom
Start  
 
Description NIHR UCL/UCLH BRC BTC biomarkers Project grant
Amount £100,000 (GBP)
Organisation National Institute for Health Research 
Sector Public
Country United Kingdom
Start 01/2014 
End 07/2016
 
Description PCRF M2PK Project Grant
Amount £167,608 (GBP)
Organisation Pancreatic Cancer Research Fund 
Sector Charity/Non Profit
Country United Kingdom
Start  
 
Description PCUK CDC7 Project Grant
Amount £140,210 (GBP)
Organisation Pancreatic Cancer UK 
Sector Charity/Non Profit
Country United Kingdom
Start 10/2011 
End 09/2014
 
Title TRANSBIL 
Description UK Multicentre collection of biological samples for the purposes of the study. Now ethically approved as TRANSBIL (TRANSlational research in BILiary tract cancer) and local SSIs set up 
Type Of Material Biological samples 
Year Produced 2009 
Provided To Others? Yes  
Impact Mcm5 test in biliary brushings has been developed into a commercial assay in discussion with Cancer Research Technology. New studies set up since 2015 include mcm5 in cystic fluid, as well as collaborative studies with Cambridge, QMUL and Imperial 
 
Description International PSC Study Group 
Organisation Oslo University Hospital
Department Gastroenterology and Hepatology
Country Norway 
Sector Hospitals 
PI Contribution I chair the Cholangiocarcinoma working group within this international collaboration, which meets at least annually
Collaborator Contribution Plans for sharing of biological samples for ongoing studies
Impact Nil
Start Year 2011
 
Description UKI Cystic Tumours Consortium 
Organisation Freeman Hospital
Country United Kingdom 
Sector Hospitals 
PI Contribution During this award have hosted approximately annual meetings with other centres with clinical and research interests in cystic tumours of the pancreas, next one in conjunction with the BSG and PCUK planned at UCLH on 25 Sept 2017. Several studies have arisen out of this, including preliminary data on MCM5 levels in cystic tumours of the pancreas.
Collaborator Contribution Collaborative studies with Cambridge and Newcastle on confocal laser endomicroscopy of cystic tumours of the pancreas, with Cambridge on genomic profiling of cystic tumours, with Newcastle on surveillance protocols.
Impact Abstract presentations at BSG and PSGBI, manuscripts in preparation.
Start Year 2015
 
Description UKI Cystic Tumours Consortium 
Organisation University of Cambridge
Country United Kingdom 
Sector Academic/University 
PI Contribution During this award have hosted approximately annual meetings with other centres with clinical and research interests in cystic tumours of the pancreas, next one in conjunction with the BSG and PCUK planned at UCLH on 25 Sept 2017. Several studies have arisen out of this, including preliminary data on MCM5 levels in cystic tumours of the pancreas.
Collaborator Contribution Collaborative studies with Cambridge and Newcastle on confocal laser endomicroscopy of cystic tumours of the pancreas, with Cambridge on genomic profiling of cystic tumours, with Newcastle on surveillance protocols.
Impact Abstract presentations at BSG and PSGBI, manuscripts in preparation.
Start Year 2015
 
Description UKI Cystic Tumours Consortium 
Organisation University of Liverpool
Country United Kingdom 
Sector Academic/University 
PI Contribution During this award have hosted approximately annual meetings with other centres with clinical and research interests in cystic tumours of the pancreas, next one in conjunction with the BSG and PCUK planned at UCLH on 25 Sept 2017. Several studies have arisen out of this, including preliminary data on MCM5 levels in cystic tumours of the pancreas.
Collaborator Contribution Collaborative studies with Cambridge and Newcastle on confocal laser endomicroscopy of cystic tumours of the pancreas, with Cambridge on genomic profiling of cystic tumours, with Newcastle on surveillance protocols.
Impact Abstract presentations at BSG and PSGBI, manuscripts in preparation.
Start Year 2015
 
Description Pancreatic Cancer UK 
Form Of Engagement Activity A formal working group, expert panel or dialogue
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Patients, carers and/or patient groups
Results and Impact Various presentations to members of Pancreatic Cancer UK, patients and the public about our research in cancer biomarker development.

Plans for ongoing links between UCL and PCUK to improve outcome in pancreatic cancer
Year(s) Of Engagement Activity 2013,2014,2015,2016