The Pancreas and Spleen Flashcards
Pancreatic Ca - Epidemiology and Risk Factors
- Epidemiology – <2% of all malignancies but causes 6500 deaths in UK per year and incidence is rising. Commonly affects men aged >60 years. Approx 95% of patients have a mutation in the KRAS2 gene.
- Risk factors – smoking, alcohol, carcinogens, diabetes mellitus, chronic pancreatitis and high fat diet.
Types of Pancreatic Tumours
Most are ductal adenocarcinoma which metastasise early and present late – 60% arise in the head, 25% in the body and 15% in the tail of the pancreas.
Tumours also arise in the ampulla of Vater (ampullary tumour) or pancreatic islet cells (insulinoma, gastrinoma, glucagonomas, somatostatinomas or VIPomas) and both have a better prognosis than adenocarcinoma.
Pancreatic Ca - Symptoms
Tumours in the head of the pancreas present with painless obstructive jaundice whilst those in the body or tail present with epigastric pain that radiates to the back and is relieved by sitting forward. Either may cause anorexia, weight loss, diabetes or acute pancreatitis.
Rarer features – thrombophlebitis migrans (arm vein becomes swollen and red followed by a leg vein), hypercalcaemia, marantic endocarditis (non-bacterial , thrombotic endocarditis), portal hypertension (due to splenic vein thrombosis) or nephrosis (due to renal vein metastases).
Pancreatic Ca - Signs
Jaundice, palpable gallbladder (Courvoiser’s law – jaundice with enlarged gallbladder is unlikely to be gallstones), epigastric mass, hepatomegaly, splenomegaly, lymphadenopathy and ascites.
Pancreatic Ca - Investigations
- Bloods – cholestatic jaundice, raised Ca19-9 is non-specific but may help assess the prognosis.
- Imaging – US or CT can show a pancreatic mass ± dilated biliary tree ± hepatic metastases. They can also be used to guide biopsy and provide staging prior to surgery or stent insertion.
Pancreatic Ca - Management
Most ductal carcinomas present with metastases and <10% are suitable for surgery.
- Surgery – pancreatoduodenectomy (Whipple’s) if fit and tumour is <3cm with no metastases.
- Post-op chemotherapy – can be used to delay disease progression as post-op mortality is high.
- Palliation of jaundice – endoscopic or percutaneous stent insertion may help jaundice and anorexia. Rarely bypass surgery is done for duodenal obstruction or unsuccessful ERCP.
- Pain relief – disabling pain may require high doses of opiates or radiotherapy.
Pancreatic Ca - Prognosis
Dismal – mean survival is <6 months and 5 year survival is <2%. Even following a Whipple’s procedure the 5 year survival is between 5-14%.
Acute Pancreatitis - Definition
An unpredictable disease with a mortality rate of 12% which is usually managed on a surgical ward.
Pathology – pancreatic inflammation causes oedema and fluid shifts leading to hypovolaemia as fluid is trapped in the gut, peritoneum and retro-peritoneum (and this is worsened by vomiting). Progression may be rapid from mild oedema to necrotising pancreatitis by enzyme mediated auto-digestion.
Acute Pancreatitis - Causes
GET SMASHED – gallstones, ethanol, trauma, steroids, mumps, autoimmune, scorpion venom, hyperlipidaemia, hypothermia or hypercalcaemia, ERCP, emboli or drugs (+ pregnancy and neoplasia).
Acute Pancreatitis - Clinical Features
- Symptoms – gradual or sudden severe epigastric or central abdominal pain (which often radiates to the back and may be relieved by sitting forward) and vomiting is usually prominent.
- Signs – fever, tachycardia, shock, jaundice, ileus, rigid abdomen ± local or general tenderness, periumbilical (Cullen’s) or flank (Grey-Turner) bruising caused by vessel auto-digestion and retroperitoneal haemorrhage.
Acute Pancreatitis - Assessing Severity
- Modified Glasgow criteria for predicting severity of pancreatitis – patients with 3 or more positive features detected within 48 hours on onset suggest severe pancreatitis. Mnemonic - PANCREAS – PaO2 <8 kPa, age >55 years, neutrophils >15 x 109/L, calcium <2 mmol/L, renal function – urea >16 mmol/L, enzymes – LDH >600 iu/L and AST >200 iu/L, albumin <32 g/L and sugar – blood glucose >10 mmol/L.
- Ransom criteria – used for alcohol induced pancreatitis (above criteria are also used for gallstones).
Acute Pancreatitis - Investigations
Serum amylase (>1000 U/mL – cholecystitis, mesenteric ischaemia and GI perforation can cause lesser rises), serum lipase, ABG to monitor oxygenation and acid-base status, abdominal x-ray to show retroperitoneal fluid, chest x-ray to exclude other causes and CT or MRI to assess severity.
Acute Pancreatitis - Management
Nil by mouth and NG tube to decrease pancreatic stimulation, fluids – give 0.9% saline until vital signs are satisfactory and urine flow is >30mL per hour, analgesia – pethidine or morphine, antibiotics if severe and if worsening transfer to ITU and consider parenteral nutrition, laparotomy and debridement.
Acute Pancreatitis - Complications
- Early – shock, ARDS, renal failure, DIC, sepsis or hypocalcaemia.
- Late – pancreatic necrosis and pseudocyst (pyrexia, a mass, persistently raised amylase or LFTs – may resolve or need draining), abscesses (need draining), bleeding (from elastase eroding major vessels – requires embolisation), thrombosis (may occur in splenic or gastroduodenal arteries causing bowel necrosis), fistulae (normally close spontaneously) or recurrent oedematous pancreatitis.
