“pancreatic cancer” usually refers to adenocarcinoma of the exocrine pancreatic ducts which accounts for 85% of all pancreatic neoplasia
95% of all malignant pancreatic tumours arise from the exocrine pancreas
endocrine pancreas may give rise to pancreatic neuroendocrine tumours such as islet cell tumours
Aetiology
mutations in the KRAS gene are the major driver of pancreatic cancer
the resulting protein controls multiple signaling pathways involved in cell growth and survival
attempts to inhibit KRAS as a Rx results in a group of genes upstream of KRAS, called ERBB becoming upregulated hence research is looking at combining KRAS inhibition (eg. MRTX1133) and ERBB inhibition (eg. Afatinib) as a Rx 1)
DDx of pancreatic mass on CT scan
cystic lesions
pancreatic true cysts
pancreatic retention cysts
pancreatic mucinous non-neoplastic cysts
lymphoepithelial cysts (rare)
pancreatic pseudocysts (walled off pancreatic fluid collections)
pancreatic cystic neoplasms:
intraductal papillary mucinous neoplasm of the pancreas
obesity, metabolic syndrome and lack of physical activity
BMI > 30 appears to have a 1.7x relative risk
metabolic syndrome (3 or more of TG > 1.7, HDL < 1.0 males or 1.3 females, fasting glucose > 6.1 and non-fasting > 7.8, BP > 130/85, BMI > 25) appears to increase risk 2)
height
appears to have an increased relative risk of 1.8x
diet, alcohol, caffeine - controversial, no clear significant risk evident on present data
clinical features
most patients present with:
anorexia, weight loss
epigastric pain
usually insidious onset with gnawing quality and may radiate to sides or back
often occurs even in small tumours
often helped by curling up into fetal position
rarely may present with pancreatitis if tumour obstructs pancreatic duct
half also present with:
nausea
back pain (especially with tumours arising in body or tail of pancreas)
some may present with progressive cholestatic jaundice (esp. if arises in pancreatic head, or late if due to liver mets), diarrhoea or vomiting
this is in part due to the thick, nearly impenetrable wall of fibrosis, or scar tissue, that surrounds most pancreatic tumors and makes it hard for drugs to access and destroy the cancer cells
in 2023, a class of anti-cancer drugs called HDAC inhibitors may help treat pancreatic cancer by modulating the activation of fibroblasts - HDAC inhibitors both turned down the growth signals from the fibroblasts to the cancer cells and it reduced the actual activation and accumulation of the fibroblasts.3)