Pancreatic cancer is cancer that starts in the pancreas, a gland that produces digestive juices and hormones.
The pancreas
The pancreas is part of the digestive system.
The pancreas is quite high up in your abdomen. It lies across your body where your ribs meet at the bottom of your breastbone, just behind your stomach. It is about 6 inches (15 centimetres) long and shaped like a leaf.
The pancreas has three parts:
the wide end is called the head
the thin end is called the tail
the bit in the middle is called the body
The pancreas is a large gland that makes digestive juices and insulin. The juices flow down a tube (pancreatic duct) into the duodenum. The duodenum is the first part of the small bowel, where it is joined to the stomach.
Another duct joins the duodenum. The bile duct comes down from the gallbladder and liver and joins the duodenum right next to the pancreatic duct. The place where the 2 bile ducts join and meet the bowel is called the ampulla of Vater.
What the pancreas does
The pancreas produces digestive juices and insulin, as well as other hormones to do with digestion.
The part which produces the digestive juices is called the exocrine pancreas. The part which produces hormones, including insulin, is called the endocrine pancreas.
Cancers that develops from these two parts can behave differently and cause different symptoms.
Digesting food
The digestive system breaks up and digests food. After about 2 hours in the stomach, the partly digested food moves into the beginning of the duodenum.
When the food reaches the duodenum, the pancreas releases its digestive juices which flow down the pancreatic duct and mix with the food.
The juices contain enzymes that help to break down the food into very small fragments. These fragments are absorbed into the body through the small bowel.
Making insulin
The pancreas makes insulin. Insulin keeps the level of sugar in the blood at a stable level. This means that the body cells get enough food, but not too much. The pancreas makes and releases more insulin if the level of sugar in the blood is high. If the level is too low, it releases less.
You have diabetes if you don't make enough insulin.
How common it is
Around 9,600 people in the UK get pancreatic cancer each year. It is the 11th most common cancer.
Who gets it
Pancreatic cancer is more common in older people. Almost half of all new cases are diagnosed in people aged 75 and over. Pancreatic cancer is uncommon in people under 40 years old.
1 in 71 people will be diagnosed with pancreatic cancer during their lifetime. It occurs equally in men and women.
In the past 10 years, pancreatic cancer rates have increased and it is thought they will continue to increase.
In England, pancreatic cancer is more common in people living in poorer areas. It is more common in White and Black people than in Asian people.
Types of pancreatic cancer
Pancreatic cancer can start in the head, body or tail of the pancreas. There are different types of cells in the pancreas. Knowing the type of cell a cancer starts in and where in the pancreas it starts helps your doctor decide about which treatment you need.
Where the cancer is
Cancer can start in the head, body or tail of the pancreas. The wide end of the pancreas is called the head. The thin end is called the tail. The bit in the middle is called the body.
Between 60 and 70 out of 100 pancreatic cancers (60-70%) start in the head of the pancreas.
Exocrine pancreatic cancers
Most pancreatic cancers are the exocrine type. This means that they start in cells that produce pancreatic digestive juices.
Adenocarcinomas
More than 8 out of 10 exocrine pancreatic cancers are adenocarcinomas. Nearly all of these are ductal adenocarcinomas. They start in the cells lining the ducts of the pancreas.
Rarer types
Rarer types of exocrine pancreatic cancer include:
Cystic tumours
Cystic tumours cause a cyst or fluid filled sac in the pancreas. Most pancreatic cysts are benign but some are cancerous. Cystic cancers can have a better outlook (prognosis) than other types of exocrine pancreatic cancer.
Cancer of the acinar cells
The acinar cells are at the ends of the ducts that produce pancreatic juices. These tumours are generally diagnosed in people at a younger age than adenocarcinomas. They are slower growing and tend to have a better outlook.
Endocrine pancreatic tumours
Endocrine tumours are uncommon. They start in the endocrine pancreas, where insulin and other hormones are made and released directly into the bloodstream. They are also called pancreatic neuroendocrine tumours (PNETS) or islet cell tumours.
About a third of these tumours produce hormones, which can cause some strange symptoms. Most of these tumours are non cancerous (benign).
They are named after the hormone they produce:
gastrinomas produce a hormone called gastrin
insulinomas produce insulin
somatostatinomas produce a hormone called somatostatin
VIPomas produce a hormone called VIP
glucagonomas produce a hormone called glucagon
Two thirds of pancreatic endocrine tumours are called non functioning tumours as they don't produce any hormones or symptoms. Most of these tumours are cancers (malignant).
Endocrine pancreatic tumours are treated differently to exocrine tumours and generally have a much better outlook (prognosis) than adenocarcinoma of the pancreas.
Other rare types of pancreatic cancer
There are other rare types of cancer of the pancreas.
Pancreatoblastoma
These very rare tumours mainly occur in children. They are sometimes linked with rare genetic conditions called Beckwith-Wiedemann syndrome and familial adenomatous polyposis (FAP).
Sarcomas of the pancreas
These are cancers of the connective tissue that hold together the cells of the pancreas. They are extremely rare.
Lymphoma
Lymphoma is a cancer of the lymphatic system. As the lymphatic system runs throughout the body, these tumours can develop in any part of the body.