Pancreatic cancer is a disease in which normal cells in the pancreas malfunction and begin to grow uncontrollably. These cancerous cells can eventually interfere with proper functioning of the pancreas and metastasize (spread) to other parts of the body.
The pancreas is a pear-shaped gland located in the abdomen between the stomach and the spine. It is about 6 inches in length and is composed of two major components: exocrine and endocrine. The exocrine component, made up of ducts and acini (small sacs on the end of the ducts), produce enzymes, which are specialized proteins released into the small intestine that help the body digest and break down food, particularly fats. It is the cells lining these pancreatic ducts that most frequently turn cancerous. These are called ductal adenocarcinomas of the pancreas and represent the most common subtype of pancreatic cancer.
Types of Pancreatic Cancer
Pancreatic cancer can be categorized into different types that depend on whether or not the cancer began in the endocrine or exocrine component. Pancreatic cancer types include
Endocrine Tumors : Endocrine tumors also referred to as pancreatic neuroendocrine tumors (PNETs) or islet cell tumors are not so common as compared to exocrine tumors. A pancreatic neuroendocrine tumor could be non-functioning that means it does not make any hormones or it could also be functioning that means it can make hormones. The base of a functioning neuroendocrine tumor is on the hormone that cells usually make –
Exocrine Tumors: They are considered as the most common type of pancreatic cancer. Adenocarcinoma that begins in gland cells is mostly seen in around 95% people who are suffering from pancreatic cancer. Ductal Adenocarcinoma is the ducts of the pancreas from where the tumor typically begins. Rarely when tumor starts in the acini then it is termed as acinar Adenocarcinoma.
Some of the other rare tumors of the pancreas are –
• Acinar Cell Carcinomas
• Cystic Tumors
• Neuroendocrine tumors
• Computed tomography (CT scan): A scanner takes multiple X-ray pictures, and a computer reconstructs them into detailed images of the inside of the abdomen. A CT scan helps doctors make a pancreatic cancer diagnosis.
• Magnetic resonance imaging (MRI):Using magnetic waves, a scanner creates detailed images of the abdomen, in particular the area around the pancreas, liver, and gallbladder.
• Ultrasound : Harmless sound waves reflected off organs in the belly create images, potentially helping doctors make a pancreatic cancer diagnosis.
• Positron emission tomography (PET scan): Radioactive glucose injected into the veins is absorbed by cancer cells. PET scans may help determine the degree of pancreatic cancer spread.
• Percutaneous needle biopsy : Under imaging guidance, a radiologist inserts a needle into the mass, capturing some tissue. This procedure is also called a fine needle aspiration (FNA).
• Endoscopic retrograde cholangiopancreatography (ERCP): A flexible tube with a camera and other tools on its end (endoscope) is put through the mouth to the small intestine, near the pancreas. ERCP can collect images from the area, as well as take a small biopsy with a brush.
• Endoscopic ultrasound : Similar to ERCP, an endoscope is placed near the pancreas. An ultrasound probe on the endoscope locates the mass, and a needle on the endoscope plucks some tissue from the mass.
• Laparoscopy is a surgical procedure that uses several small incisions. Using laparoscopy, a surgeon can collect tissue for biopsy, as well as see inside the abdomen to determine if pancreatic cancer has spread. However, laparoscopy has higher risks than other biopsy approaches.
Stage is a term used in cancer treatment to describe the extent of spread of the cancer. The stages of pancreatic cancer are used to guide treatment and to classify patients for clinical trials. The stages of pancreatic cancer are:
• Stage 0: No spread. Pancreatic cancer is limited to a single layer of cells in the pancreas. The pancreatic cancer is not visible on imaging tests or even to the naked eye.
• Stage I: Local growth. Pancreatic cancer is limited to the pancreas, but has grown to less than 2 centimeters across (stage IA) or greater than 2 centimeters (stage IB).
• Stage II: Local spread. Pancreatic cancer has grown outside the pancreas, or has spread to nearby lymph nodes
• Stage III: Wider spread. The tumor has expanded into nearby major blood vessels or nerves but has not metastasized.
• Stage IV: Confirmed spread. Pancreatic cancer has spread to distant organs.
The treatment of pancreatic cancer depends on the size and location of the tumor, whether the cancer has spread, and the person's overall health. In many cases, a team of doctors will work with the patient to determine the best treatment plan. The current treatment options for pancreatic cancer are surgery, radiation therapy, or chemotherapy. All of these treatments may be used at any stage of the disease, whether it is an early cancer or an advanced cancer.
Surgery may involve removing all or part of the pancreas, depending on the location and size of the cancer within the pancreas. If the cancer is still confined to the pancreas' head, or widest part of the pancreas, the surgeon may perform a Whipple procedure. This is an extensive operation where the surgeon removes the head of the pancreas and part of the small intestine, bile duct, and stomach, and then reconnects the digestive tract and biliary system. An experienced surgeon should perform this procedure.
Different types of surgery are performed depending on the purpose of the surgery:
Laparoscopy, Sometimes, the surgeon may choose to start with a laparoscopy. During a laparoscopy, several small holes are made in the abdomen and a tiny camera is passed into the body while a patient receives anesthesia, which is medication to help block the awareness of pain. This helps the surgeon find out if the cancer has spread to other parts of the abdomen. If it has, surgery to remove the primary tumor is generally not recommended.
Surgery to remove the tumor. Different types of surgery are used depending on where the tumor is located in the pancreas. In all of the surgeries discussed below, nearby lymph nodes are removed as part of the operation. More than one type of surgeon, as well as other specialists, will usually be involved in your surgery.
• If the cancer is located only in the head of the pancreas, the surgeon may do a Whipple procedure. This is an extensive surgery in which the surgeon removes the head of the pancreas and part of the small intestine, bile duct, and stomach, and then reconnects the digestive tract and biliary system. An experienced pancreatic cancer surgeon should perform this procedure.
• If the cancer is located in the tail of the pancreas, the common operation is a distal pancreatectomy, in which the surgeon removes the tail and body of the pancreas, as well as the spleen.
• If the cancer has spread throughout the pancreas, or is located in many areas in the pancreas, a total pancreatectomy may be needed. A total pancreatectomy is the removal of the entire pancreas, part of the small intestine, a portion of the stomach, the common bile duct, the gallbladder, the spleen, and nearby lymph nodes.
Chemotherapy is a cancer treatment that uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping the cells from dividing. When chemotherapy is taken by mouth or injected into a vein or muscle, the drugs enter the bloodstream and can reach cancer cells throughout the body (systemic chemotherapy). When chemotherapy is placed directly into the spinal column, an organ, or a body cavity such as the abdomen, the drugs mainly affect cancer cells in those areas (regional chemotherapy). The way the chemotherapy is given depends on the type and stage of the cancer being treated.
Radiation therapy is a cancer treatment that uses high-energy radiation beams to kill cancer cells. There are two types of radiation therapy. External radiation therapy uses a machine outside the body to send radiation toward the cancer. Internal radiation therapy uses a radioactive substance sealed in needles, seeds, wires, or catheters that are placed directly into or near the cancer.
More recently, the era of targeted therapies has generated a lot of interest in discovering better approaches for patients with pancreatic cancer. Targeted therapy uses drugs that attack specific abnormalities within cancer cells. Targeted therapies can work by:
• Blocking the process that changes normal cells into cancer, thereby stopping the abnormal growth behavior of a tumor
• Preventing the formation of blood vessels that bring nutrients to the tumor
You may want to ask some questions before your treatment begins: