Dr Claire Smith, Consultant Radiologist St James University Hospital Leeds

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1 Dr Claire Smith, Consultant Radiologist St James University Hospital Leeds

2 Imaging in jaundice and 2ww pathway Image protocol Staging Limitations

3 Pancreatic cancer Refer people using a suspected cancer pathway referral (for an appointment within 2 weeks) for pancreatic cancer if they are aged 40 and over and have jaundice. [new 2015] Consider an urgent direct access CT scan (to be performed within 2 weeks), or an urgent ultrasound scan if CT is not available, to assess for pancreatic cancer in people aged 60 and over with weight loss and any of the following: diarrhoea back pain abdominal pain nausea vomiting constipation new-onset diabetes. [new 2015]

4 Red flags e.g. weight loss, older age Pancreatic protocol CT Painful, pyrexia, acute onset US +/-MRCP

5 Pros Useful first line examination for jaundice Can assess for gallstones and most obstructing pancreatic masses will be visible No contrast or radiation Bedside test Cons Cannot stage a tumour Difficult to get views in obese patients and bowel gas can obscure pancreas

6 Detects gallstones Can also identify obstructing duct stones No radiation No contrast

7 Pancreatic parenchyma; duct usually not visible Aorta Splenic vein Focal mass replaces head of pancreas Pancreatic duct obstructed/ dilated Superior mesenteric/ portal vein flattened Atrophic pancreas

8 CT is the first line test when a patient presents with jaundice and pancreatic cancer is suspected. Pancreatic protocol: 1. Non- contrast upper abdomen Baseline to compare post contrast to- is it enhancement or a dense lesion? A small proportion of CBD stones will be visible on CT 2. Arterial phase (35-40 seconds) upper abdomen- needed to stage tumour and improves visibility as most pancreatic tumours enhance less than the pancreatic parenchyma 3. Portal Venous phase- Needed to stage involvement of portal vein and optimal abdominal soft tissue enhancement to look for metastases Staging CT must be performed before ERCP/ EUS

9 Double duct sign 1 - pancreatic head lesion or ampullary tumour must be excluded T4 tumour 2 - encasing arteries. obstructing pancreatic duct Staging CT must be performed before ERCP/ EUS 1.Case courtesy of Dr Chris O'Donnell, Radiopaedia.org, rid: Case courtesy of Dr Natalie Yang, Radiopaedia.org, rid: 6722

10 For solid obstructing or duct strictures, pre- ERCP imaging is key to accurate staging and characterisation. Once an endoscopic intervention has been performed. Differentiating post-procedure inflammatory change from the primary pathology is challenging. For pancreatic and ampullary tumours, MRI does not have role to play in characterising prior to intervention or diagnostic EUS In particular, consider if MRI is appropriate in patients whose fitness precludes curative treatment.

11 EUS and CT have a similar accuracy for pre- operative T staging. Protocol for CT pancreas is key- arterial phase and portal venous phase to assess vascular involvement. Post duct stent inflammatory changes can limit interpretation of repeat staging Relationships to vascular structure is key to determining operabilitythere are features indicating borderline or inoperability; these aresignificant coeliac, HA or SMA deformation or contact but less than 180 degrees. Long segment SMV occlusion. T4- clear involvement of coeliac, SMA or HA greater than 180 degrees

12 T1 Tumour 2 cm or less T1a Tumour 0.5 cm or less T1b Tumour greater than 0.5 cm and less than 1 cm T1c Tumor greater than 1 cm but no more than 2 cm T2 Tumour more than 2 cm but no more than 4 cm T3 Tumour more than 4 cm in greatest dimension T4 Tumour involves coeliac axis, superior mesenteric artery and/or common hepatic artery N1 Metastases in 1 to 3 nodes N2 Metastases in 4 or more nodes

13 SMA contact <180 degrees. Staging depends on size of tumour but this is still borderline operability

14 Reserved to answer specific questions: The parenchyma Is the pancreas abnormal (focal / diffuse)? Is the mass solid or cystic? Is it benign or malignant? Ducts Is there a structural abnormality for acute pancreatitis? Is there chronic pancreatitis? Pre procedure map for surgical / endoscopic intervention Used to follow up or characterise cysts: To look for malignant features in the cyst AND Patients with IPMNs have an increased risk of pancreatic cancer. Surveillance of patients with a genetic risk of pancreatic cancer For suspected liver metastases

15 Main duct IPMN MCN SCA Pseudocyst

16 Intraductal Papillary Mucinous Neoplasm (IPMN) Benign lesions with malignant potential. They produce mucin and communicate with the pancreatic duct. Their probability of malignant transformation varies depending on the site and as such should be characterised into one of three types: - 1. Main duct IPMN: Segmental or diffuse dilatation of the main pancreatic duct of >5mm without other causes of obstruction Branch duct IPMN: A pancreatic cyst >5mm in diameter that communicates with the main pancreatic duct. (Pseudocyst remains a differential) - 3. Mixed type IPMN (imaged right): Has features of both

17 A pitfall on CT- is it truly cystic? To confidently diagnose a cyst the lesion must have well defined non- enhancing margins and be fluid density (0HU +/- 10) Consider alternative diagnosis if not: Cystic degeneration/ necrosis of solid pancreatic tumours -Adenocarcinoma -Invasive features- vessel invasion, jaundice -Less well defined -Extra- pancreatic extension -Heterogeneous contents Pancreatic neuroendocrine tumours (PNET) -Hypervascular mass with central necrsis -Arterial ring enhancement

18 64 year old male imaged for CLL. Serial imaging less than one year apart. Atypical features on baseline: heterogeneity, irregular enhancing margin. Histology: Adenosquamous tumour Features are of an invasive solid tumour. The wedge shaped splenic hypodensity is an infarct secondary to vascular invasion.

19 Nice guidance advises PET-CT for the following indications: In obstructive jaundice: 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. Pancreatic abnormalities on imaging If the diagnosis is still unclear, offer FDG-PET/CT and/or EUS with EUS-guided tissue sampling. In Pancreatic Cancer Staging Offer fluorodeoxyglucose-positron emission tomography/ct (FDG-PET/CT) to people with localised disease on CT who will be having cancer treatment (surgery, radiotherapy or systemic therapy).

20 1. Can miss small tumours underlying pancreatitis- need to follow up 2. A small proportion (around 10%) of pancreatic tumours will have the same enhancement as the pancreas- limits diagnosis and measurement. 3. Can miss peritoneal disease- not visible on CT or PET-CT 4. Ability to stage a tumour after biliary intervention or neoadjuvant chemotherapy is limited 5. Delays in treatment- often needs repeating due to delays in surgery or starting chemotherapy 6. Volume of referrals and delays in reporting

21 CT commonly over- stages on post neo-adjuvant cases as there is limited ability in distinguishing viable from treated tumour. There are no studies determining the accuracy of MRI or EUS in this context.

22 Pancreatic malignancy can present as pancreatitis therefore there must be a clear clinical history and cause of pancreatitis. This is challenging in cases referred to MDT with little or no clinical history. Dilated PD in pancreatitis raises concern for an obstructing pancreatic cancer Cystic neoplasms with large locules can appear similar to postpancreatitis collections. Cases with no clear cause for pancreatitis or a dilated pancreatic duct should be referred for central MDT review.

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24 Post pancreatitis changes versus malignancy

25 Post pancreatitis changes versus malignancy T2 T1 WE T1 + gad art DWI ADC T1 + gad delayed Pancreatic cancer

26 1. An accurate clinical history is needed to choose the correct test and to make a diagnosis 2. CT is the primary imaging of choice in pancreatic cancer diagnosis and staging. 3. To stage accurately imaging must be performed using the correct protocol (including an arterial phase) and BEFORE biliary intervention. 4.If a malignancy is suspected in a patient over 40 then an arterial and portal venous phase examination is advised