Pancreatic Cancer

Introduction

Pancreatic cancer can be caused by exocrine cells, which secrete substances into the pancreatic ducts or endocrine cells, which release substances into the blood.
90% of pancreatic cancer is from the first group due to ductal adenocarcinomas and is the focus of this video. Usually, patients present late with advanced disease complaining of jaundice and weight loss. These have the worst survival of all gastrointestinal malignancies
On the other hand, endocrine tumours present with excess hormone secretion, for example, insulin, glucagon, or gastrin, and are mostly benign.

If we look at the pancreas a bit closer, it has a head, a body, and a tail.

About 70% of tumours are located within the head of the pancreas, 10% are in the body, 10% are in the tail, and 10% are multifocal.

It metastasises early to lymph nodes, then to the peritoneum, and to liver via the portal vein. Distant mets are usually found in the lung and brain.

Key risk factors include chronic pancreatitis, cigarette smoking, age between 65 to 75, obesity, type II diabetes, and a positive family history.

Consider blood tests including liver function tests. Abnormal LFTs are associated with the degree of obstructive jaundice. There are biomarkers for pancreatic cancer including CA 19-9, also known as carcinoembryonic antigen. It is mostly helpful for preoperative staging, identifying recurrence in patients who have undergone resection, and in assessing the response to treatment.

Consider imaging including an ultrasound. This will seek masses in pancreas and liver, dilated bile ducts and stones in the gall bladder. Primary imaging is usually done with a pancreatic protocol CT scan. This can show tumour extent, the presence and volume of liver metastases and help determine the feasibility of surgical resection.

When ultrasound and/or CT indicate a pancreatic head carcinoma may be resectable, endoscopic ultrasound (EUS) can give added detail. In this, an ultrasound probe is positioned in the second part of the duodenum via a gastroscope. Needle aspiration sampling of suspicious lesions can be performed via the gastric lumen for cytology.

The management of pancreatic cancer is based on the extent of the disease. The only potentially curative treatment is surgery via operative resection. Alternative treatments, for more extensive disease should include palliation. Chemotherapy and radiotherapy may be used as palliative treatment as well as in the adjuvant setting with surgery. Surgery can also be palliative

The Whipple operation, also known as a pancreaticoduodenectomy, is the standard type of operation where resection of the pancreatic head is indicated. It is a major undertaking with high operative morbidity and mortality.

For the palliation of pancreatic cancer, pain management is key. Analgesia can often be relieved by permanent coeliac ganglion blockade, performed percutaneously. Obstructive jaundice can usually be relieved by inserting a biliary stent via an endoscopic retrograde cholangiopancreatography.

The most common symptoms are usually constitutional ones including weight loss, anorexia and weakness, with about 80% of patients experiencing these. Constitutional symptoms indicate advanced disease and rapid weight loss is usually associated with unresectability.

Abdominal pain occurs in about 60% of presentations. Its site is generally epigastric. Its onset is usually insidious and there for two months before presentation. The pain of advanced pancreatic carcinoma is characterised as severe, continuous, and typically ‘deep’ and ‘gnawing’. It often radiates to the sides and through to the back and is associated with nausea and sporadic vomiting. Its timing is usually nocturnal and poorly relieved by analgesics but sometimes eased by leaning forwards from sitting in ‘the pancreatic position’. It can be so severe, that the pain may drive patients to suicide.

One common sign is jaundice, which occurs in 50% of presentations and is associated with pruritus, pale stools, and dark urine. This is often without pain early on and develops over a few weeks.

The jaundice is caused by common bile duct compression in its course through the pancreatic head. As a result, the proximal bile duct dilates, and the gall bladder distends. Courvoisier’s law states that jaundice and a painless palpable gallbladder is very likely to be pancreatic cancer as gallstones causing obstructive jaundice will be painful on palpation.

Other signs of metastatic disease may be present including ascites and left supraclavicular lymphadenopathy, known as Virchow's node.

Keep in mind that the initial presentation of pancreatic cancer varies according to tumour location. Pancreatic head tumours will compress the common bile duct in its course through the organ. This makes presentations with jaundice, steatorrhea, and weight loss more common.

My mnemonic for pancreatic cancer is based on its classic triad of clinical features: pain, weight loss, and jaundice. I remember a patient that is crippled whittled and looking like a skittle needs a whipple. This short rhyme tells you if a patient is crippled with abdominal pain, whittled with weight loss and cachexia, and yellow as a jaundiced skittle, they can only be surgically cured with a Whipple’s procedure.