Exploring pancreatic cancer types, causes and symptoms

Exploring pancreatic cancer types, causes and symptoms

Pancreatic cancer refers to a type of cancer that manifests itself when malignant cells develop in a section of the pancreas. Pancreatic cancer is the thirteenth most popular cancer globally, with about two hundred thousand cases reported in the year 1996, amounting to 2%, including Australia. The case fatality rate for pancreatic cancer is extremely high.

Therefore, the total number of deaths from this cancer is virtually identical to the number of new cases. Despite the fact that the five year survival rate for pancreatic cancer has improved in the recent years from about 1% in 1960 to 1963 to approximately 4 to 5% in 1986 to 1993, the case fatality rate remains extremely high.

Roughly 70% of pancreatic cancers are known to occur in the head of the pancreas. This condition results into the blockage of the bile duct. Consequently, decreasing the flow of bile, thus causing a pile up of bile pigment in the blood.


Types of Pancreatic Cancer

Pancreatic cancer is categorized into exocrine and endocrine cancers. Pancreatic cancer normally refers to pancreatic adenocarcinoma or ductal adenocarcinoma, which involves the exocrine part of the pancreas. Ductal adenocarcinomas occur mostly in the head of the pancreas gland, but they also appear in the body as well as the tail of the gland.

Another kind of pancreatic cancer is endocrine pancreatic cancer, also referred to as neuroendocrine or islet cell cancer. These cancers normally occur in the body and tail of the pancreas and they generally grow slowly, thus presenting a better prognosis. Lymphomas along with sarcomas hardly arise in the pancreatic gland. They are addressed the same as if they are situated somewhere else in the body.

Apart from the types of pancreatic cancers listed above, other kinds include: solid and psedopapillary cancer of the pancreas, adenosquamous variants of ductal adenocarcinoma, and acinar cancers. The cancerous pancreatic cells can also move through the lymphatic system and the blood to adjacent parts of the body. When cancer cells leave the pancreas and extend to other parts of the human body, the resulting cancer type is referred to as metastatic cancer.

Tumours can also be located in the endocrine cells of the pancreas; however, pancreas endocrine tumours occur rarely. These tumours may be cancerous or noncancerous, and they tend to grow slowly. They are grouped as functional or non-functional. Most of the functional tumours are malignant as well as cancerous.


Staging of Patients with Pancreatic Cancer

The preoperative TNM staging of pancreatic cancer is based on the extent of the intrusion by the main mass, the existence or absence of malignant lymph nodes, and evidence of metastatic disease. The T (tumour) stage of pancreatic cancer is categorised as T1-T4 based on the size of the mass and the extent of intrusion.

The earliest stage, T1, comprises of an intra-pancreatic mass that measures two cc in diameter. Masses that have invaded tissues adjacent to the pancreas, including the duodenum, stomach, bile duct, and peri-pancreatic fat are classified as T3 lesions. T4 lesions are the most advanced ones, and they have spread into adjacent vessels, including the superior mesenteric vessels, portal vein and its branches.


Symptoms of pancreatic cancer

Pain in the abdomen is one of the main symptoms of pancreatic cancer. Individuals with this condition get discomfort around the upper abdomen region. The pain later spreads to the back. This is experienced when one is lying down and while eating.

Individuals experience the pain since the tumour causes a blockage in both the stomach and duodenum. The condition may also cause inflammation on the pancreas or liver, which causes pain around the abdomen. Jaundice is another symptom that indicates an individual is suffering from pancreatic cancer.

Jaundice is also a symptom and is identified by the following characteristics: yellowish skin, yellowish urine, an itchy skin and bowel changes. It mainly presents itself when the cancer has grown at the head of the pancreas. It develops when the bile duct is blocked by the tumour. This causes excess bilirubin in the body. This is a yellow chemical produced by bile and should be excreted by the liver.

Weight loss is another potential symptom. Patients with this condition lose a lot of weight due to lack of nutrients. Pancreatic cancer affects the capability of the pancreas to yield digestive enzymes that function in food digestion. Diabetes is a condition as well as a symptom in patients with pancreatic cancer.

This cancer destroys the major function of the pancreas that is to produce insulin that is used by the body in regulation of sugar levels in the blood. Individuals with diabetes experience the following symptoms: frequent urination, weight loss, excessive thirst and fatigue.


Causes of pancreatic cancer

Cigarette smoking is a major cause of pancreatic cancer. Cigarettes and other tobacco containing products contain the nitrosamine chemical that is carcinogenic. Age is also a cause of pancreatic cancer as the risk of obtaining the condition increases with age. Individuals between the age of sixty and eighty are at a high probability of developing the cancer. Diabetes is a symptom and also a cause of the disease. Individuals with pancreatic cancer are more likely to get diabetes and vice versa.

Obesity is also linked to causing pancreatic cancer. Individuals who are overweight are less physically active which makes them produce excess insulin. This increases their chances of developing pancreatic cancer due to diabetes.

Genetics can be another factor. Individuals with a family history of pancreatic cancer are at a high probability of obtaining the disease. Inflammation of the pancreas that is referred to as pancreatitis is another cause. Patients that suffer from the inflammation for a long period are more likely to get the cancer.

Alcohol can also cause the cancer since it is linked to chronic pancreatitis. Diet can cause the growth of the cancer too, as diets containing too much fat and meat lead to pancreatic cancer. Lack of certain nutrients such as selenium may also lead to pancreatic cancer. Other types of cancers affecting the digestive system such as bowel or bladder cancer can lead to the development of pancreatic cancer.

An amplified risk of pancreatic cancer has been demonstrated from several known genetic syndromes, for which causative genes have been identified. These syndromes consist of familial breast cancer, familial atypical multiple mole and melanoma, hereditary non-polyposis colorectal cancer syndrome, and hereditary chronic pancreatitis. Among the syndromes, familial breast cancer accounts for the largest portion of familial clustering of pancreatic cancer in Australia.


References:

1. What is pancreatic cancer: http://www.cancersa.org.au/information/a-z-index/what-is-pancreatic-cancer

2. Types of pancreatic cancer: http://www.pancreaticcancer.net.au/patientcorner/pancreatic-cancer/what-is-pancreatic-cancer/types-of-pancreatic-cancer

3. Pancreatic cancer: http://www.cancervic.org.au/about-cancer/cancer_types/pancreatic_cancer

4. Pancreatic cancer: http://www.myvmc.com/diseases/pancreatic-cancer-adenocarcinoma-of-the-pancreas/