Pancreatic Cancer: Glossary of Terms (R-S)

- R –

Radiation: 
1. Rays of energy. Gamma rays and X-rays are two of the types of energy waves often used in medicine. 
2. The use of energy waves to diagnose or treat disease.

Radiation therapy: The use of high-energy rays to damage cancer cells, stopping them from growing and dividing. Like surgery, radiation therapy is a local treatment that affects cancer cells only in the treated area. Radiation can come from a machine (external radiation) or from a small container of radioactive material implanted directly into or near a tumor (internal radiation). External radiation therapy is usually given on an outpatient basis in a hospital or clinic. Patients are not radioactive during or after external radiation therapy. For internal radiation therapy, the patient stays in the hospital for a few days. The implant may be temporary or permanent. After an implant is removed, there is no radioactivity in the body. The amount of radiation in a permanent implant goes down to a safe level before the patient leaves the hospital. Side effects of radiation therapy depend on the treatment dose and the part of the body treated. The most common side effects of radiation are fatigue, skin reactions (such as a rash or redness) in the treated area, and loss of appetite. Radiation therapy can cause inflammation of tissues and organs in and around the body site that is radiated. Radiation therapy can also cause a decrease in the number of white blood cells. Although the side effects of radiation therapy can be unpleasant, they can usually be treated or controlled. Furthermore, in most cases, they are not permanent.

Radiologist: A physician specialized in radiology, the branch of medicine that uses ionizing and nonionizing radiation for the diagnosis and treatment of disease.

Randomized controlled trials: Randomized controlled trials are medical studies designed to test whether a treatment works. Patients are split into groups. One group is given the treatment being tested (for example, an antidepressant drug) while another group (called the comparison or control group) is given an alternative treatment. This could be a different type of drug or a dummy treatment (a placebo). Researchers then compare the effects of the different treatments.

Recurrence: The reappearance of the cancer after a period of time when it was undetectable. Recurrence can appear in the same place as the primary tumor or in another part of the body.

Red cells: Produced by bone marrow, they circulate in the blood and carry oxygen to all parts of the body.

Referring Order: A referral made by the survivor's physician certifying that life expectancy is six months or less if the pancreatic cancer runs its likely course.

Regimen: A plan or a regulated course, such as a diet, exercise, or treatment, that is designed to give a good result. A low-salt diet is one type of dietary regimen.

Remission: Disappearance of detectable disease.

Resectable: Able to be removed (resected) by surgery.

Respite Care: A part of hospice care that provides the primary caregiver a short break from caregiving duties while the cancer survivor stays in a hospital facility.

Risk Factor: A characteristic or behavior that has been associated with an increased chance of developing a disease. It is not necessarily a cause of the disease but increases the likelihood of developing the disease.

- S –

Sarcoma: A malignant tumor that mimics connective tissues (bone, cartilage, muscle) under the microscope.

Scan: As a noun, the data or image obtained from the examination of organs or regions of the body by gathering information with a sensing device.

Screening: Checking for disease when there are no symptoms

Secondary Tumor: A cancerous tumor that has spread from its original site of formation (the primary tumor) to another location in the body. Secondary tumors are treated with the same medical therapies as the primary tumor.

Sedation: A feeling of relaxation and calm, or the act of creating a feeling of calm by administering a drug.

Seizure: A sudden movement of muscles that cannot be controlled.

Sensation: In medicine and physiology, sensation refers to the registration of an incoming (afferent) nerve impulse in that part of the brain called the sensorium, which is capable of such perception. Therefore, the awareness of a stimulus as a result of its perception by sensory receptors. (Sensory is here synonymous with sensation.)

Sepsis: An infection of the blood.

Serous: Inflammation of the serous tissues of the body. The serous tissues line the lungs (pleura), heart (pericardium), and the inner lining of the abdomen (peritoneum) and organs within.

Side Effect: An undesired effect of a treatment. Problems occur when a treatment damages healthy cells and have undesirable effects on the body.

Simethicone: A medication used for the removal of excess gas in the intestinal tract. It helps the air in the stomach to be more readily expelled by burping or passing gas. The drug does not prevent the accumulation of gas created by intestinal bacteria or from swallowed air. It does not make intestinal gases dissolve.

Single-Blind Trial: A clinical trial in which only the doctor knows which therapy the participant is receiving. The participant may receive the standard treatment or the experimental treatment. This prevents bias on behalf of participants in treatment trials.

Small intestine: A long (20 foot) tube that stretches from the stomach to the large intestine. It helps absorb nutrients from food as the food is transported to the large intestine. There are three sections: the duodenum, the jejunum and the ileum. Due to its proximity to the pancreas, the duodenum is the section most often affected by pancreatic cancer.

Soluble Fiber: A digestible fiber that dissolves readily in water. Soluble fiber imparts gummy or gel-like characteristics to foods. This fiber includes some hemicelluloses, pectins, gums, and mucilages. Food sources include fruits, vegetables, legumes, seeds, oats, barley, and rye. Additionally, pectin, psyllium, and FOS are available in over-the-counter forms or may be added to liquid nutritional supplements. Possible health effects include lowered blood cholesterol, slowed glucose absorption, slowing transit time of food through the upper gastrointestinal tract, and bulking of stool to form a soft stool.

Somatostatin: A polypeptide produced by the hypothalamus and the pancreas. Somatostatin produced by the hypothalamus acts as a neurohormone that inhibits the secretion of other hormones, especially growth hormone and thyrotropin. Somatostatin secreted by the pancreas acts as a hormone that inhibits the secretion of the other pancreatic hormones, insulin and glucagon, and reduces the activity of the digestive system.

Spleen: An organ that is located in the upper-left part of the abdomen, not far from the stomach, that produces lymphocytes, which are important elements in the immune system. The spleen is the largest lymphatic organ in the body. The spleen also filters blood, serves as a major reservoir for blood, and destroys blood cells that are aged (or abnormal, as in the case of sickle cells).

Splenic Artery: A large artery within the abdomen that arises from an arterial vessel called the celiac trunk, which emerges from the aorta. The splenic artery supplies blood not only to the spleen, but also to the esophagus, stomach, duodenum, liver, and pancreas.

Splenic Vein: A vein formed by the union of several small veins that return blood from the stomach, pancreas and spleen. The splenic vein is a major contributor to the portal vein which goes to the liver.

Squamous cell: A flat, scale-like cell.

Stable Disease: A cancerous tumor that has neither increased nor decreased in size or location.

Stage: A classification system used to describe the extent of disease. For pancreatic cancer:

1. Stage I refers to tumors confined to the pancreas and tumors which have only extended into the duodenum, bile duct or soft tissues immediately around the pancreas.

2. Stage II cancers have extended into the spleen, stomach, large intestine or adjacent large vessels.

3. Stage III tumors have spread to regional lymph nodes and.

4. Stage IV has spread (metastasized) to distant sites such as the liver.

In general, the lower the stage is, the better are the prognosis.

Steatorrhea: Excessive amounts of fat in the stool. Sometimes this can appear as an oil slick on top of the toilet water after the patient has had a bowel movement.

Stent: A tube designed to be inserted into a vessel or passageway to keep it open. Stents are inserted into narrowed coronary arteries to help keep them open after balloon angioplasty. The stent then allows the normal flow of blood and oxygen to the heart. Stents placed in narrowed carotid arteries (the vessels in the front of the neck that supply blood to the brain) appear useful in treating patients at elevated risk for stroke. Stents are also used in other structures such as the esophagus to treat a constriction, the ureters to maintain the drainage of urine from the kidneys, and the bile duct to keep it open.

Stomach: The digestive organ that is located in the upper abdomen, under the ribs. The upper part of the stomach connects to the esophagus, and the lower part leads into the small intestine. When food enters the stomach, muscles in the stomach wall create a rippling motion (peristalsis) that mixes and mashes the food. At the same time, juices made by glands in the lining of the stomach help digest the food. After about 3 hours, the food becomes a liquid and moves into the small intestine, where digestion continues.

Stool: The solid matter discharged in a bowel movement.

Sunitinib (Suten): A targeted therapy drug approved in 2011 by the FDA to treat advanced pancreatic neuroendocrine tumors. It may help slow or prevent cancer cells from multiplying and dividing. It may also slow the formation of blood vessels that provide nutrients and oxygen to the tumor.

Superior Mesenteric Artery: A major artery arising from the largest artery in the body, the aorta. The superior mesenteric artery is located near the pancreas and supplies blood to the small intestines, colon, and part of the pancreas.

Superior Mesenteric Vein: A major vein located behind the neck of the pancreas.

Surgeon: A physician who treats disease, injury, or deformity via operative or manual methods to physically change body tissues. The definition of surgeon has begun to blur in recent years as surgeons have begun to minimize the cutting, employing new technologies that are minimally invasive (such as using scopes and lasers).

Surgery: The branch of medicine that employs operations in the treatment of disease or injury. Surgery can involve cutting, abrading, suturing, or otherwise physically changing body tissues and organs.

Survivor: A term used to describe any person who has been diagnosed with cancer, no matter how long it has been since the diagnosis. Definitions vary throughout the cancer community and are best-defined by the individual.

Symptom: An indication that a person has a condition or disease. Some examples of symptoms for pancreatic cancer include jaundice, weight loss, fatigue, nausea, vomiting, and pain.

Systemic treatment: Treatment involving the whole body, usually using drugs.