investigations and diagnosis
Last edited 05/2020 and last reviewed 05/2022
- full blood count
- may reveal a normochromic anaemia or thrombocytosis or both
- raised serum bilirubin, alkaline phosphatase and γ‑glutamyltransferase in obstructive jaundice (serum aspartate aminotransferase (AST) and serum alanine aminotransferase (ALT) may also be raised to a lesser extent)
- may be impaired glucose tolerance or diabetes
- tumour markers
- carbohydrate 19-9 (CA19-9) - also known as sialylated Lewis (a) antigen
- although most widely used serum tumor marker it is not specific for pancreatic cancer (a sensitivity of 80% and specificity of 73% for pancreatic cancer
- is a useful to assess response to treatment and as a surveillance tool after treatment
- imaging
- initial examination
- abdominal ultrasound –
- double duct sign - bile duct dilation (>7 mm, or >10 mm if previous cholecystectomy) with pancreatic duct dilation (>2 mm) may be a sign of pancreatic cancer
- other findings - liver metastases and ascites
- further evaluations
- triple phase computed tomography preceded by non-contrast computed tomography
- best method for detecting pancreatic neoplasms and assessing resectability
- endoscopic ultrasound
- useful especially for small tumours (<3cm)
- can detect involvement of loco regionl lympnodes
- also used to guide fine needle aspiration (FNA) for cytological evaluation of lesions in which there is diagnostic uncertainty
- positron emission tomography (PET) combined with CT (PET-CT)
- it is more sensitvie in detecting pancreatic cancer and extra hepatic metastasis
- MRI combined with magnetic resonance cholangiopancreatography (MRCP)
- endoscopic retrograde cholangiopancreatography (ERCP)
- is an effective way of confiming pancreatic adenocarcinoma with sensitivity of 90-95%
- an invasive procedure whith 5-10% isk of significant complications hence reserved for therapeutic procedure for biliary obstruction or for the diagnosis of unusual pancreatic neoplasms
NICE state that with respect to diagnosis of pancreatic cancer:
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Diagnosis:
- People with obstructive jaundice
- if obstructive jaundice and suspected pancreatic cancer, offer a pancreatic protocol CT scan before draining the bile duct.
- if the diagnosis is still unclear, offer fluorodeoxyglucose-positron emission tomography/CT (FDG-PET/CT) and/or endoscopic ultrasound (EUS) with EUS-guided tissue sampling.
- take a biliary brushing for cytology if:
- endoscopic retrograde cholangiopancreatography (ERCP) is being used to relieve the biliary obstruction and
- there is no tissue diagnosis
- People without jaundice who have pancreatic abnormalities on imaging
- a pancreatic protocol CT scan should be offered to people with pancreatic abnormalities but no jaundice.
- if the diagnosis is still unclear, offer FDG-PET/CT and/or EUS with EUS-guided tissue sampling.
- if cytological or histological samples are needed, offer EUS with EUS-guided tissue sampling
- People with obstructive jaundice
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