Pancreatic cancer occurs when there is an uncontrolled multiplication of cells in the pancreas. These cells all derived from a single clone; due to certain factors, these cancer-initiating cells, have acquired certain characteristics that allow them to divide indefinitely without going through natural death. Early cancer cells are confined to the tissue of the pancreas; as the tumor grows, some cancer cells can migrate from their original site to form metastases in other tissues in the body.
Usually, cancer cells grow within the pancreas. In most cases, the tumor develops in the ducts that carry the pancreatic enzymes to the duodenum; however, in a small group of individuals, sometimes the cancer cells begin in the portion of pancreas that produce insulin, islets of Langerhans.
There are several forms of pancreatic cancer, depending on the types of cells involved; the two main types are:
- Exocrine pancreatic cancer(adenocarcinomas) – adenocarcinomas account for nearly 95% of exocrine pancreatic cancer. Usually, this type of cancer is formed in the excretory duct of the pancreas which opens into the duodenum.
- Endocrine pancreatic cancer – also known as known as neuroendocrine tumor, or pancreatic islet cell tumor, endocrine pancreatic cancer refers to any cancer that develops in the hormone-producing cells of the pancreas. There are in total 5 subtypes of endocrine cancers of the pancreas,depending on the hormone-making cell affected:
1) insulinomas – the cancer forms in the cells that produce insulin;
2) glucagonomas – the cancer forms in the cells that produce glucagon;
3) gastrinomas – the cancer forms in the cells that produce gastrin;
4) somatostatinomas – the cancer forms in the cells that produce somatostatin;
5) VIPomas – also known as Verner Morrison syndrome, VIPomas forms in the cells that produce vasoactive intestinal peptide (VIP).
Pancreatic Cancer Statistics Pancreatic Cancer Risk Factors
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