Definition and Overview
Pancreatic cancer is a kind of malignancy arising from the pancreas, an organ found beneath the stomach. This condition is characterised by the uncontrolled growth of pancreatic cells resulting in the formation of mass or tumor, which can invade nearby organs and other parts of the body. Pancreatic cancer is not common and is responsible for approximately 3% of all malignancies in the United States. The disease usually occurs in older patients and is more commonly seen in men than in women.
Pancreatic cancer is difficult to diagnose and is usually in the later stages when discovered. Although pancreatic cancer survival rates have been steadily improving, pancreatic cancer prognosis remains poor with only 5-year survival rate. More than 30,000 people die of pancreatic cancer every year.
This type of cancer can affect either the exocrine pancreas, the portion of the pancreas that produces digestive enzymes or the endocrine pancreas, the portion that produces hormones such as insulin and glucagon. Malignancies of the exocrine pancreas are more common, with the most common type being the pancreatic adenocarcinoma. This accounts for approximately 80-90% of all pancreatic malignancies. Other types of exocrine cancers include acinar cell carcinoma, cystadenocarcinoma, and solid pseudopapillary tumor, to name a few. Neuroendocrine tumors, meanwhile, may be “functioning” and can produce symptoms related to the hormones they produce. These tumors usually have a better survival rate than tumors of the exocrine pancreas.
Pancreatic Cancer Causes
The exact cause of pancreatic cancer remains unknown, although studies have shown that it involves a combination of environmental and genetic factors.
Cigarette smoking is a significant risk factor in the development of pancreatic cancer. Cigars and other tobacco products are also associated with a higher risk of this malignancy. Studies show that smokers have a two-fold increase in risk compared to non-smokers.
Patients with glucose intolerance, diabetes mellitus, and chronic pancreatitis have also been shown to have increased risks of the development of pancreatic cancer. Obesity is another factor associated with this condition.
Patients with a family history of pancreatic cancer, specifically in a first-degree relative, have a higher risk of developing the disease. Certain genetic syndromes, such as Lynch syndrome and multiple endocrine neoplasia or MEN, are also associated with pancreatic cancer.
Pancreatic Cancer Symptoms
The initial symptoms of pancreatic cancer are non-specific, which is why it is difficult to diagnose the disease in its early stages. Usual symptoms include nausea, loss of appetite, weight loss, and fatigue.
One of the classic signs of pancreatic cancer is painless jaundice. This occurs when the tumor is located in the head of the pancreas and causes obstruction in the biliary tract. Patients can also present with pruritus or itchiness, and yellowing of the skin and the eyes. Other symptoms include darkening of the urine and changes in stool character, usually becoming lighter in color.
When the tumor is located in other parts of the pancreas, or when the tumor becomes big enough, it can also produce abdominal pain. Abdominal pain may also occur when the tumor spreads or impinges on the nerves near the pancreas. The typical pain caused by pancreatic cancer is located in the epigastric area, often radiating to the back. The pain is usually more evident after eating and at night and may worsen when the person is lying on his back.
Patients with pancreatic cancer may develop signs and symptoms of malabsorption. They may also suffer from diarrhea and greasy stools as well as experience early satiety if the tumor becomes bigger and causes obstruction.
Pancreatic cancer may also present as new-onset diabetes in a previously well, elderly patient. The usual symptoms of diabetes are being thirsty and hungry all the time, and urinating more than normal.
Who to See and Types of Treatments Available
Patients with any of the aforementioned symptoms should seek consult immediately. Your physician might ask you to undergo several blood examinations, particularly tumor markers such as CA 19-9. You may also have to undergo imaging studies, such as an abdominal ultrasound or a triple contrast CT scan in order for the doctor to make an accurate diagnosis. If you are indeed discovered to have a tumor in your pancreas, imaging studies will be able to determine the stage of cancer, and whether the mass can be removed completely through surgery.
Pancreatic cancer stages
Stage 0 – The cancer only affects a single layer of cells in the pancreas
Stage II – Localised pancreatic cancer; has not spread to nearby organs
Stage III – The cancer has spread to nearby nerves or blood vessels
Stage IV - The cancer has metastasized to distant organs
The stage of the disease will determine the treatment. If the mass is found to be resectable, you will be referred to a surgeon. In some centers, a multidisciplinary team manages cases of pancreatic cancer, which include various specialists in surgery, endocrinology, and medical oncology. If you have pancreatic cancer, it is very important to be managed at a large center with expertise in pancreatic surgery and chemotherapy.
Surgery remains to be the main method of treatment for pancreatic cancer. Curative surgery for pancreatic cancer, however, is possible in only about 20% of patients, mostly those who were diagnosed early. For patients with resectable tumors located at the head of the pancreas, a pancreaticoduodenectomy, better known as the Whipple procedure, is performed. In this procedure, the pancreas and its attachments are removed, and the stomach and the cystic duct are connected to the small intestines. For patients with resectable masses located at the tail of the pancreas, a distal pancreatectomy can be done. Chemotherapy is usually given after surgery to minimise the risk of recurrence of the malignancy.
In cases where the mass is too big and is not amenable to excision, palliative surgery may be provided to alleviate or delay the onset of symptoms. Chemotherapy may also be given in order to extend a patient’s lifespan and improve his quality of life. Radiation therapy may also be given. For patients with stage 4 pancreatic cancer, palliative care, with focus on pain control, may also be an option.
National Pancreatic Cancer Foundation: https://npcf.us/
Pancreatic Cancer Action Network: https://www.pancan.org/