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Obesity: If your body stores more energy than you need, this can make you overweight. The excess energy is stored in your fat cells. If your weight goes above a certain level, doctors call this obesity. Obesity is considered a medical condition. The excess weight can be a strain on your bones and joints. And if you are obese, you're more likely to get other diseases. Doctors have developed a scale for telling how much excess weight you have. This measure, called the body mass index (BMI), depends on your height.
Obstruction: Blockage of a passageway. See, for example: Airway obstruction; Intestinal obstruction.
Octreotide: Octreotide (brand name Sandostatin, Novartis Pharmaceuticals) is an octapeptide that mimics natural somatostatin pharmacologically, though it is a more potent inhibitor of growth hormone, glucagon, and insulin than the natural hormone. If the tumor is not amenable to surgical removal and is causing symptoms by secreting functional hormones, octreotide, may lessen the symptoms, and sometimes also slows tumor growth.
Oncologist: A physician who specializes in the diagnosis and treatment of cancer. After a cancer diagnosis is made, it is the oncologist’s role to explain the cancer diagnosis and the meaning of the disease stage to the patient; discuss various treatment options; recommend the best course of treatment; deliver optimal care; and improve quality of life both through curative therapy and palliative care with pain and symptom management.
Oncology: The field of medicine that is devoted to cancer. Clinical oncology consists of three primary disciplines: medical oncology (the treatment of cancer with medicine, including chemotherapy), surgical oncology (the surgical aspects of cancer including biopsy, staging, and surgical resection of tumors), and radiation oncology (the treatment of cancer with therapeutic radiation).
Open Label Trial: A clinical trial in which both the participant and the medical staff are aware of which treatment the person is receiving.
Operation: In medicine, a surgical procedure. Many operations are named after persons. They range from A to Z, from the Abbe operation (on the lip) to the Ziegler operation (on the eye).
Organ: A relatively independent part of the body that carries out one or more special functions. Examples of organs include the eyes, ears, heart, lungs, and liver.
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Pain: An unpleasant sensation that can range from mild, localized discomfort to agony. Pain has both physical and emotional components. The physical part of pain results from nerve stimulation. Pain may be contained to a discrete area, as in an injury, or it can be more diffuse, as in disorders like fibromyalgia. Pain is mediated by specific nerve fibers that carry the pain impulses to the brain where their conscious appreciation may be modified by many factors.
Pain threshold: The point at which a person becomes aware of pain.
Palliative care: 1) Medical or comfort care that reduces the severity of a disease or slows its progress rather than providing a cure. For incurable diseases, in cases where the cure is not recommended due to other health concerns, and when the patient does not wish to pursue a cure, palliative care becomes the focus of treatment. For example, if surgery cannot be performed to remove a tumor, radiation treatment might be tried to reduce its rate of growth, and pain management could help the patient manage physical symptoms. 2) In a negative sense, provision only of perfunctory health care when a cure is possible.
Palpation: A simple technique in which a doctor presses on the surface of the body to feel the organs or tissues underneath.
Pancreas: A spongy, tube-shaped organ that is about 6 inches long and is located in the back of the abdomen, behind the stomach. The head of the pancreas is on the right side of the abdomen. It is connected to the upper end of the small intestine. The narrow end of the pancreas, called the tail, extends to the left side of the body. The pancreas makes pancreatic juices and hormones, including insulin and secretin. Pancreatic juices contain enzymes that help digest food in the small intestine. Both pancreatic enzymes and hormones are needed to keep the body working correctly. As pancreatic juices are made, they flow into the main pancreatic duct, which joins to the common bile duct, which connects the pancreas to the liver and the gallbladder and carries bile to the small intestine near the stomach. The pancreas is thus a compound gland in the sense that it is composed of both exocrine and endocrine tissues. The exocrine function of the pancreas involves the synthesis and secretion of pancreatic juices. The endocrine function resides in the million or so cellular islands (the islets of Langerhans) that are embedded between the exocrine units of the pancreas. Beta cells of the islets of Langerhans secrete insulin, which helps control carbohydrate metabolism. Alpha cells of the islets of Langerhans secrete glucagon, which counters the action of insulin.
Pancreas Tissues: There are two main types of tissue found in the pancreas: exocrine tissue and endocrine tissue. Most of the pancreas - about 95% - is exocrine tissue that produces pancreatic enzymes to aid digestion. A healthy pancreas makes about 2.2 pints (1 liter) of these enzymes every day.
Pancreatectomy: A surgical procedure in which part or the entire pancreas is removed.
Pancreatic: Having to do with the pancreas.
Pancreatic cancer: A malignant tumor of the pancreas. Pancreatic cancer has been called a 'silent' disease because early pancreatic cancer usually does not cause symptoms. If the tumor blocks the common bile duct, and bile cannot pass into the digestive system, the skin and whites of the eyes may become yellow (jaundiced), and the urine may become darker as a result of accumulated bile pigment (bilirubin).
Pancreatic Duct: The main exocrine duct of the pancreas. Pancreatic enzymes from smaller ducts empty into the pancreatic duct, join the common bile duct, and enter the duodenum.
Pancreatic Endocrine Cancer: A rare cancer that forms in the islets of Langerhans cells (a type of cell found in the pancreas). Also called islet cell carcinoma.
Pancreatic Function Test: A test used to help diagnose problems in the pancreas, such as gastrinomas and pancreatitis. It measures the ability of the pancreas to respond to the hormone secretin (a hormone that causes other substances to be released by the stomach, liver, and pancreas). Secretin is given to the patient by a tube put through the nose or throat into the small intestine and stomach or by injection into a vein. After a certain amount of time, samples are taken to be sent to a laboratory for testing. It is a type of pancreatic function test. Also called secretin stimulation test.
Pancreatic insulin-producing tumor: An abnormal mass that grows in the beta cells of the pancreas that make insulin. Pancreatic insulin-producing tumors are usually benign (not cancer). They secrete insulin and are the most common cause of low blood sugar caused by having too much insulin in the body. Also called beta cell neoplasm, beta cell tumor of the pancreas, and insulinoma.
Pancreatic Juice: Fluid made by the pancreas. Pancreatic juices contain proteins called enzymes that support digestion.
Pancreatic polypeptide: A small protein made by the pancreas that helps control the release of other substances made by the pancreas. The amount of pancreatic polypeptide in the blood increases after a person eats. It may also increase with age, and in certain diseases, such as diabetes and pancreatic cancer. Also called PP.
Pancreatic pseudocyst: A pancreatic pseudocyst is a circumscribed collection of fluid rich in pancreatic enzymes, blood, and necrotic tissue, typically located in the lesser sac of the abdomen. Pancreatic pseudocysts are usually complications of pancreatitis, although in children they frequently occur following abdominal trauma. Pancreatic pseudocysts account for approximately 75% of all pancreatic masses. The prefix pseudo- ( Latin for "false") distinguishes them from true cysts, which are lined by epithelium; pseudocysts are lined with granulation tissue.
Pancreatitis: Inflammation of the pancreas. Of the many causes of pancreatitis, the most common are alcohol consumption and gallstones. Other causes include medications (azathioprine, estrogen, thiazides, metronidazole, valproic acid, and tetracycline), trauma, abdominal surgery, abnormalities of the pancreas and intestine, and infections such as mumps. Acute pancreatitis usually begins with pain in the upper abdomen that may last for a few days. The pain may be sudden and intense, or it may begin as a mild pain that is aggravated by eating and slowly grows worse. The abdomen may be very tender. Other symptoms may include nausea, vomiting, and fever. The patient often feels and looks very sick. Chronic pancreatitis usually follows many years of alcohol abuse and may cause pain; malabsorption of food, leading to weight loss; and diabetes, if the insulin-producing cells of the pancreas (islet cells) are damaged.
Papillary: A term used to describe certain tumors which grow in finger-like projections. Pathologists mostly use this term.
Paracentesis: A surgical procedure to remove fluid from the abdomen.
Parathyroid Glands: A group of small endocrine glands located in the neck, behind the thyroid gland. These glands help regulate calcium levels in the blood.
Parenchyma: The key elements of an organ essential to its functioning, as distinct from the capsule that encompasses it and other supporting structures. The parenchyma is thus opposed to the connective tissue framework, or stroma, of an organ.
Partial Response: A decrease in the size of a tumor in response to treatment. The amount of decrease needed to use the term partial response is specified in the clinical trial protocol.
Pathologist: A physician who identifies diseases and conditions by studying abnormal cells and 'tissues.
Percutaneous: Through the skin. For example, a percutaneous biopsy is a biopsy that is obtained by putting a needle through the skin in order to obtain tissue within the body for examination.
Peri-ampullary: Around the ampulla of Vater. The peri-ampullary region is comprised of 4 structures; the ampulla, the duodenum, the bile duct and the head of the pancreas. It is sometimes difficult to tell which structure a tumor originated in. In such cases the diagnosis will be a peri-ampullary tumor.
Peritoneum: A thin membrane lining the cavity of the abdomen.
Permanent section: Thin slices of biopsy tissue that are mounted on slides and looked at under a microscope. A permanent section takes several days to prepare. It tells doctors if the tissue is cancer, the type of cancer it is, and other information that helps to plan treatment.
Peutz-Jeghers syndrome: Peutz-Jeghers syndrome (PJS) is an inherited condition that puts people at an increased risk for developing hamartomatous polyps in the digestive tract, as well as breast, colorectal, and other types of cancer. A hamartoma is a growth of normal-appearing tissue that builds up into a benign (noncancerous) tumor. However, the growth can transform into cancer over time. Cancer begins when normal cells begin to change and grow uncontrollably, forming a mass called a tumor. A tumor can be noncancerous or malignant.
Pharmacy: A location where prescription medications are sold. A pharmacy is constantly supervised by a licensed pharmacist.
Platelets: Platelets are small disc-shaped particles found in your blood (along with red blood cells and white blood cells). Platelets form the clots that stop the bleeding when you've been cut. People who don't have enough platelets have problems with bleeding too much.
Plexus: 1. In medicine, a network or tangle of lymphatic vessels, nerves, or veins. For example, the brachial plexus is a network of nerves leading to the arm. In general, any interwoven entity made up of elements in a structure or system.
Positron Emission Tomography (PET Scan): PET scans involve injecting a form of sugar that contains a radioactive atom into the blood. Cancer cells absorb large amounts of this sugar. A special camera can show where these cells are. This test is useful to see whether the cancer has spread to the lymph nodes or other places.
Practical Care: A type of hospice care provided by housekeepers, social workers, and volunteers. Practical care covers everything from insurance and other financial matters to routine chores.
Primary cancer: A cancer in the organ it started in. A primary cancer of the pancreas is one that started in the pancreas as opposed to a cancer that started somewhere else and only later spread to the pancreas.
Probability: The likelihood that something will happen. For example, a probability of less than .05 indicates that the likelihood of something occurring by chance alone is less than 5 in 100, or 5 percent. This level of probability is usually taken as the level of biologic significance, so a higher incidence may be considered meaningful. Abbreviated as p.
Prognosis: A forecast for the probable outcome of a disease based on the experience of large numbers of other patients with similar stage disease. Importantly, making a prognosis is not an exact science. Some patients with poor prognosis beat the odds and live longer than anyone would have predicted.
Progressive Cancer: The increase in size of a cancer tumor or the spread, or metastasis, of the tumor to another part of the body.
Protease: An enzyme secreted by the pancreas that breaks down proteins.
Psyllium: A soluble fiber helpful in regulating bowel movements. Psyllium is found in fiber supplements such as Metamucil.
PTC: A test sometimes used to help diagnose cancer of the pancreas. A thin needle is put into the liver. Dye is injected into the bile ducts so blockages can be seen on x-rays.
Pylorus: A thick ring of muscle (a sphincter) between the stomach and duodenum. This sphincter helps control the release of the stomach contents into the small intestine.