Pancreatic cancer is a type of malignancy that develops in the pancreas, a long, flat organ that lies between the stomach and the spine. It has two primary functions; endocrine function, which is responsible for secreting hormones (such as insulin) to control blood sugar levels, and exocrine function, which produce pancreatic enzymes that aid in digestion. This page will primarily focus on exocrine pancreatic cancers.
The pancreas has three main parts: the head, the body, and the tail. The head of the pancreas is attached to the duodenum (the first portion of the small intestine) via the pancreatic duct. Another tube, called the common bile duct, carries bile from the liver, passes through the pancreatic duct and empties into the duodenum. These cancers can develop anywhere in the pancreas, but usually develop in the head of the pancreas.
Pancreatic cancer is more common in males, and is often diagnosed over the age of 45. However, anyone can develop this disease.
Types of Pancreatic Cancer
There are two main types of pancreatic cancers, which are categorised by the type of cells the cancer originates from.
Exocrine Pancreatic Cancer
Exocrine pancreatic tumours are the most common subtype of this disease. It most often occurs as an adenocarcinoma (cancer arising from mucus-producing glands in organs), however, less common subtypes include adenosquamous carcinoma (a type of cancer affected squamous cells and gland-like cells), acinar cell carcinoma (a cancer arising from acinar cells in the epithelium that make enzymes), squamous cell carcinoma (cancer arising from squamous cells in the epithelium) and undifferentiated carcinoma (carcinomas with patternless cancer growth). Exocrine tumours usually begin in the lining of the pancreatic duct, and may not have as good of a prognosis as other subtypes.
Endocrine Pancreatic Cancer
Endocrine cancers, or Neuroendocrine cancers, are a complex group of tumours that develop in the neuroendocrine system, which is responsible for regulating important bodily functions such as heart rate, blood pressure and metabolism. They most commonly develop in the gastro-intestinal tract, pancreas, and the lungs; however, they can develop anywhere in the body. These tumours develop from neuroendocrine cells, which are responsible for receiving signals from the nervous system and producing hormones and peptides (small proteins) in response.
Pancreatic neuroendocrine tumours (pNETs), or islet cell tumours, are rare carcinomas (cancers arising from bone and soft tissue lining the organs) that develop in the pancreas. The pancreas is responsible for producing a variety of hormones, such as insulin, gastrin, and glucagon. There are several types of pNETS, including:
Treatment
If pancreatic cancer is detected, it will be staged and graded based on size, metastasis (whether the cancer has spread to other parts of the body) and how the cancer cells look under the microscope. Staging and grading helps your doctors determine the best treatment for you.
Cancers can be staged using the TNM staging system:
- T (tumour) indicates the size and depth of the tumour.
- N (nodes) indicates whether the cancer has spread to nearby lymph nodes.
- M (metastasis) indicates whether the cancer has spread to other parts of the body.
This system can also be used in combination with a numerical value, from stage 0-IV:
- Stage 0: this stage describes cancer cells in the place of origin (or ‘in situ’) that have not spread to nearby tissue.
- Stage I: cancer cells have begun to spread to nearby tissue. It is not deeply embedded into nearby tissue and had not spread to lymph nodes. This stage is also known as early-stage cancer.
- Stage II: cancer cells have grown deeper into nearby tissue. Lymph nodes may or may not be affected. This is also known as localised cancer.
- Stage III: the cancer has become larger and has grown deeper into nearby tissue. Lymph nodes are generally affected at this stage. This is also known as localised cancer.
- Stage IV: the cancer has spread to other tissues and organs in the body. This is also known as advanced or metastatic cancer.
Cancers can also be graded based on the rate of growth and how likely they are to spread:
- Grade I: cancer cells present as slightly abnormal and are usually slow growing. This is also known as a low-grade tumour.
- Grade II: cancer cells present as abnormal and grow faster than grade-I tumours. This is also known as an intermediate-grade tumour.
- Grade III: cancer cells present as very abnormal and grow quickly. This is also known as a high-grade tumour.
Once your tumour has been staged and graded, your doctor may recommend genetic testing, which analyses your tumour DNA and can help determine which treatment has the greatest chance of success. They will then discuss the most appropriate treatment option for you.
Treatment is dependent on several factors, including location, stage of disease and overall health.
Treatment options for exocrine pancreatic cancer may include:
- Surgery, potentially including:
- Whipple procedure/pancreaticoduodenectomy (removes portions of affected organs, such as the pancreas, gallbladder, stomach, small intestine, and lymph nodes).
- Distal pancreatectomy (removal of the tail and potentially parts of the body of the pancreas).
- Total pancreatectomy (complete removal of the pancreas, as well as potentially the spleen, gall bladder, common bile duct, part of the stomach, small bowel, and nearby lymph nodes).
- Chemotherapy.
- Radiation therapy.
- Ablation and embolization.
- Targeted therapy.
- Clinical trials.
- Palliative care.
For more information on the treatment options, please refer to the Rare Cancers Australia Treatment Options page.
Risk factors
While the cause of pancreatic cancer remains unknown, the following factors may increase your risk of developing the disease:
- Being a tobacco smoker (or having a history of it).
- Obesity.
- Having a diet high in red and processed meat.
- Excessive alcohol consumption.
- Having certain conditions, including:
- Long-term diabetes.
- Long-term pancreatitis.
- Having a specific cyst in the pancreatic ducts, known as intraductal papillary mucinous neoplasms (IPMNs).
- Having a family history of pancreatic cancer.
- Genetic mutations, including BRCA1 and BRCA2.
Not everyone with these risk factors will develop the disease, and some people who have the disease may have none of these risk factors. See your general practitioner (GP) if you are concerned.
Early symptoms
Exocrine pancreatic cancers have different symptoms to endocrine pancreatic cancers.
Symptoms of exocrine pancreatic cancers may include:
- Jaundice (yellowing of the eyes and the skin).
- Changes in bathroom habits, such as dark urine and pale-coloured and greasy stools.
- Itchy skin.
- Abdominal and/or back pain.
- Unexplained weight loss/loss of appetite.
- Nausea and vomiting.
- Fatigue.
- Enlargement of the gallbladder.
- Blood clots in the leg.
- New, onset diabetes/changes in blood sugar levels.
- Indigestion.
Not everyone with the symptoms above will have cancer, but see your GP if you are concerned.
Diagnosis/diagnosing
If your doctor suspects you have an pancreatic cance, they may order the following tests to confirm the diagnosis and refer you to a specialist for treatment.
Physical examination
Your doctor will collect your overall medical history, as well as your current symptoms. Following this, they may examine your body to check for any abnormalities.
Imaging & blood tests
The doctor will take images of your body using magnetic resonance imaging (MRI), a computed tomography scan (CT scan), x-rays, ultrasounds and/or positron emission tomography (PET scan), depending on where it is suspected the cancer is. The doctor may also look at other parts of the body and looks for signs of metastasis.
Additionally, a blood test may be taken to assess your overall health and help guide treatment decisions.
Biopsy
Once the location of the cancer has been identified, the doctor will perform a biopsy to remove a section of tissue using a needle. This is often done by a fine needle aspiration (FNA), a core needle biopsy (CNB), or during a surgical procedure (such as a laparoscopy or an endoscopy). These samples will then be analysed for cancer cells.
Prognosis (Certain factors affect the prognosis and treatment options)
While it is not possible to predict the exact course of the disease, your doctor may be able to give you a general idea based on the rate and depth of tumour growth, susceptibility to treatment, age, overall fitness, and medical history. Generally, early-stage pancreatic cancers have a better prognosis and survival rates. However, if the cancer is advanced and has spread, the prognosis may not be as good and there may be a higher risk of cancer recurrence. It is very important to discuss your individual circumstances with your doctor to better understand your prognosis.
References
Some references are to overseas websites. There may be references to drugs and clinical trials that are not available here in Australia.