Pancreatic Cancer Flashcards
What is pancreatic cancer?
Pancreatic cancer will typically refer to ductal carcinoma of the pancreas, which comprises up to 90% of primary pancreatic malignancies. The remaining number can be divided into exocrine tumours (such as pancreatic cystic carcinoma) and endocrine tumours (derived from islet cells of the pancreas).
Who is commonly affected by pancreatic cancer?
It is rare under 40 years of age, with 80% of cases occurring between 60-80yrs.
Briefly describe the pathophysiology of pancreatic cancer
The most common type of pancreatic cancer is ductal carcinoma (90% of primary pancreatic malignancies). Other rarer forms include cystic tumours, ampullary cell tumours and islet cell tumours, which all often have a much better prognosis.
As the cancer spreads, direct invasion of local structures typically involves the spleen, transverse colon and adrenal glands. Lymphatic metastasis typically involves regional lymph nodes, liver, lungs, and peritoneum. Metastasis is common at the time of diagnosis.
What are the risk factors for pancreatic cancer?
There are few clear risk factors for the development of carcinoma of the pancreas. Those that have been identified include smoking and chronic pancreatitis. There may also be a hereditary element, as 7% of patients have a family history of the disease.
Late onset diabetes mellitus is an additional risk factor. Those diagnosed with diabetes >50yrs have an 8x greater risk of developing pancreatic carcinoma in the following three years than the general population.
What are the clinical features of pancreatic cancer?
Note: signs and symptoms
Approximately 80% of cases of pancreatic carcinoma are unresectable at diagnosis, testament to the late and often vague and non-specific nature of its presentation.
The specific clinical features can depend on the site of the tumour:
-
Obstructive jaundice
- Due to compression of the common bile duct (present in 90% of cases at time of diagnosis), typically painless
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Weight loss
- Due to the metabolic effects of the cancer, or secondary to exocrine dysfunction
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Abdominal pain (non-specific)
- Due to invasion of the coeliac plexus or secondary to pancreatitis
Less common presentations include acute pancreatitis or thrombophlebitis migrans (a recurrent migratory superficial thrombophlebitis, caused by a paraneoplastic hypercoagulable state).
What are the clinical features of pancreatic cancer?
Note: on examination
On examination, patients may appear cachectic, malnourished and jaundiced. On palpation, an abdominal mass in the epigastric region may be felt, as well as an enlarged gallbladder (as per Courvoisier’s Law).
What is Courvoisier’s law?
Courvoisier’s law states that in the presence of jaundice and an enlarged/palpable gallbladder, malignancy of the biliary tree or pancreas should be strongly suspected, as the cause is unlikely to be gallstones.
This sign may be present if the obstructing tumour is distal to the cystic duct. In reality an enlarged gallbladder is present in less than 25% of patients with pancreatic cancer.
What investigations should be ordered for pancreatic cancer?
Note: laboratory investigations
Any suspected pancreatic cancer should warrant initial blood tests, including FBC (anaemia or thrombocytopenia) and LFTs (raised bilirubin, alkaline phosphatase, and gamma-GT, showing an obstructive jaundice picture).
CA19-9 is a tumour marker with a high sensitivity and specificity for pancreatic cancer, yet its role is in assessing response to treatment rather than for initial diagnosis.
What investigations should be ordered for pancreatic cancer?
Note: imaging
The initial imaging for pancreatic cancer is commonly an abdominal ultrasound, which may demonstrate a pancreatic mass or a dilated biliary tree (as well as potential hepatic metastases and ascites if very late stage disease).
CT imaging (using a pancreatic protocol) is both the most important investigation in terms of diagnosis, but also the most prognostically informative as it can stage disease progression. A chest-abdomen-pelvis CT scan will be further required once pancreatic cancer has been diagnosed for staging; a PET-CT scan may be warranted in those with localised disease on CT who will be having cancer treatment
Endoscopic ultrasound (EUS) may be subsequently be used to guide fine needle aspiration biopsy in order to histologically evaluate the lesion, if the diagnosis is still unclear. ERCP can also be used to access the lesion for biopsy or cytology, if in a suitable location.
Briefly describe the surgical management of pancreatic cancer
The only curative management option is currently radical resection:
- For patients with tumours of the head of the pancreas, the most common surgery with curative intent is pancreaticoduodenectomy, also known as a Whipple’s procedure
- Pylorus-preserving resections can be attempted in certain cases
- For patients with tumours of the body or tail of pancreas, a distal pancreatectomy can often be performed
What are the complications of surgery for pancreatic cancer?
Absolute contraindications for surgery include peritoneal, liver and distant metastases.
What are the complications of surgery for pancreatic cancer?
There is a high morbidity associated with these procedures (up to 40%) and specific complications include formation of a pancreatic fistula, delayed gastric emptying and pancreatic insufficiency.
Briefly describe Whipple’s procedure
A Whipple’s procedure involves the removal of:
- The head of the pancreas
- The antrum of the stomach
- The 1st and 2nd parts of the duodenum
- The common bile duct
- The gallbladder
All viscera removed in the operation are done so due to their common arterial supply (the gastroduodenal artery), shared by the head of the pancreas and the duodenum.
Following this, the tail of the pancreas and the hepatic duct are attached to the jejunum, allowing bile and pancreatic juices to drain into the gut, whilst the stomach is subsequently anastomosed with the jejunum allowing for the passage of food.
Briefly describe chemotherapeutic management of pancreatic cancer
Adjuvant chemotherapy, generally with 5-flourouracil, is recommended after surgery as it has been demonstrated to improve survival following the ESPAC-1 trial.
In metastatic disease the use of FOLFIRINOX regime (folinic acid, 5-fluorouracil, irinotecan, and oxaliplatin) is advised in those with a good performance status, however has yielded only modest improvements in survival; gemcitabine therapy can be considered for people with locally advanced pancreatic cancer who are not well enough to tolerate FOLFIRINOX.
Briefly describe palliative care for pancreatic cancer
The majority of patients with pancreatic cancer are not candidates for curative surgery, but instead require palliative care involvement.
Obstructive jaundice and associated pruritis can be relieved with the insertion of a biliary stent, either via ERCP or percutaneously.
Palliative chemotherapy, such as with a gemcitabine-based regime, can be trialled in patients with a reasonable performance status.
Exocrine insufficiency is common in advanced disease or those who have had significant excision of the pancreas, lead to malabsorption and steatorrhoea; this can initially be treated with enzyme replacements (including lipases), such as Creon®.
