Cancer Dictionary

Acinar cell carcinoma is a rare type of cancer that originates in the acinar cells of the pancreas, which are responsible for producing digestive enzymes. It is characterized by the abnormal growth of these cells, leading to the formation of a tumor in the pancreas.

Acquired resistance refers to the ability of a disease-causing organism, such as bacteria or cancer cells, to develop resistance to a drug or treatment that was previously effective. This change occurs over time, often due to genetic mutations or adaptations that allow the organism to survive despite the presence of the treatment.

Acute Lymphoblastic Leukemia (ALL) is a rare type of cancer characterized by the rapid production of abnormal white blood cells in the bone marrow. These cells impede the production of normal blood cells, triggering symptoms like fatigue, fever, and bleeding. ALL is most common in children but can also occur in adults. Treatment often involves chemotherapy, radiation, targeted therapy, or stem cell transplant.

Acute Myeloid Leukemia (AML) is a rapid-developing type of blood cancer that affects the myeloid line of cells in the bone marrow. Marked by an overproduction of immature white blood cells known as blasts, AML interferes with the production of normal blood cells, leading to anemia, infection, and bleeding complications. Fast diagnosis and treatment are essential due to its aggressive nature.

Acute promyelocytic leukemia (APL) is a subtype of acute myeloid leukemia, a fast-growing cancer of the blood-forming cells in the bone marrow. In APL, immature blood cells called promyelocytes accumulate in the bone marrow, reducing the production of healthy white and red blood cells and platelets. This can lead to fatigue, susceptibility to infections, and increased bleeding.

Adenocarcinoma is a type of cancer that starts in the glandular cells, which are found in various organs of the body. These cells secrete mucus, digestive enzymes, or hormones, among other substances. Adenocarcinomas can occur in different parts of the body, most commonly in the lungs, colon, prostate, and breasts. It is a malignant tumor and treatment varies depending on the location and stage of the disease.

Adenocarcinoma in situ is a type of cancer where abnormal cells are found in the glandular tissue lining but have not spread to nearby tissues. It is considered an early form of cancer and is often treatable if detected early.

Adenoma is a type of non-cancerous (benign) tumor that originates from glandular tissue. While most adenomas are non-threatening, they have the potential to become malignant (cancerous). Adenomas can form in any gland in the body, including the lungs, adrenal glands, colon, and pituitary glands, among others. The symptoms and treatment vary depending on their location.

Adenopathy refers to the medical condition characterized by the abnormal enlargement of the lymph nodes, which are vital parts of the immune system. The swelling may be due to infections, chronic inflammatory conditions, or malignancies. It's often detected through physical examination or imaging studies.

Adenosis refers to a medical condition where there is an abnormal growth or development in glandular tissues in the body. It results from an alteration in the normal cells of a gland, which may lead to benign or malignant tumors. Its manifestation greatly varies, depending on the location in the body and its histological type.

Adjuvant endocrine therapy is a treatment used to reduce the risk of cancer coming back after primary treatments like surgery. It involves using hormone-blocking drugs to prevent cancer cells from growing, particularly in hormone-sensitive cancers like breast cancer.

Adjuvant chemotherapy is a treatment approach using drugs to kill cancer cells left in the body after primary treatments, such as surgery or radiation. This method is typically employed to lower the risk of cancer recurrence and improve the patient's overall survival rate.

Adjuvant therapy is a treatment given in addition to the primary (main) treatment, commonly used in cancer care to kill hidden or potential cancer cells and reduce the risk of the cancer returning. It can include chemotherapy, radiation therapy, hormone therapy, targeted therapy, or biological therapy.

Adolescents and Young Adults (AYA) is a term typically used in healthcare to denote a specialized group ranging from ages 15 to 39. This group experiences unique health issues, including specific cancers and mental health disorders, which may require distinct treatment strategies and healthcare models.

Affinity chromatography is a laboratory technique used to purify and separate proteins or other molecules from a mixture based on their specific interactions with a ligand attached to a stationary phase.

Allogeneic refers to cells, tissues, or organs that are sourced from a genetically different individual of the same species. In healthcare, it often describes donor material for transplants such as Allogeneic Stem Cell Transplant, where donor stem cells are introduced to the recipient to aid disease treatment.

An allogeneic bone marrow transplant is a medical procedure where a patient receives healthy blood-forming stem cells from a genetically similar, but not identical, donor to replace their damaged or diseased bone marrow.

An allogeneic stem cell transplant is a medical procedure where a patient receives blood-forming stem cells from a genetically similar, but not identical, donor. This treatment is often used for conditions affecting the bone marrow or blood, such as leukemia and lymphoma.

Alopecia, also known as hair loss, is a medical condition that involves the thinning or complete loss of hair from areas where it normally grows. This can affect the scalp, face, and body, and can occur due to various factors including genetics, hormonal changes, immune system abnormalities, or as a side effect of certain treatments or medications.

Alpha-fetoprotein (AFP) is a specific protein produced primarily in the fetus's liver and is present in both the amniotic fluid and mother's blood. Post-birth, its production usually stops, with high levels in adults often associated with liver diseases, germ cell tumors, or an indication of certain cancers. AFP, hence, serves as a bio-marker in medical diagnostic procedures.

Ameloblastoma is a rare, benign tumor that typically occurs in the jaw near the molars. It originates from cells involved in tooth development and can cause swelling and pain in the affected area. Although benign, it can be aggressive and invade nearby bone and tissue.

Anal cancer is a rare type of malignancy arising from the anal canal or rectum. It starts when healthy cells in or around the anus change and grow out of control, forming a mass. Risk factors include increasing age, history of HPV infections, and smoking. Symptoms may include rectal bleeding, pain, or changes in bowel movements. Treatment often involves chemotherapy, radiation, or surgery.

"Anaplastic" is a term often used in the medical field, particularly in oncology, to describe cancer cells that have lost their distinct characteristics and appear undifferentiated. These cells exhibit irregular growth and lack the typical specialized features of healthy cells, often making the disease more aggressive and harder to treat.

Anaplastic ependymoma is a rare and aggressive type of brain tumor that originates from ependymal cells lining the ventricles of the brain and the central canal of the spinal cord. It is characterized by rapid growth and a tendency to spread within the central nervous system.

Anaplastic oligodendroglioma is a rare and aggressive type of brain tumor that originates from oligodendrocytes, which are cells that support nerve cells in the brain. It is characterized by its rapid growth and tendency to spread, making it more challenging to treat compared to other types of brain tumors.

Anaplastic thyroid cancer is a rare, aggressive type of thyroid cancer characterized by uncontrolled growth of cells in the thyroid, a gland located at the base of the neck. This cancer often grows quickly and spreads to other parts of the body, making it difficult to treat. Despite its severity, it accounts for only about 1-2% of all thyroid cancers.

Androgen is a type of hormone that plays a crucial role in the development and maintenance of male characteristics in mammals. It includes hormones like testosterone and dihydrotestosterone, which are produced primarily in male testes and female ovaries to regulate sexual development, muscle mass, bone density, and hair growth.

Androgen Deprivation Therapy (ADT) is a treatment approach primarily used for prostate cancer. It works by reducing or blocking the production or action of androgens, male sex hormones like testosterone, which can promote the growth of cancer cells. ADT can be administered through surgery, medications, or hormone therapy and is effective in slowing down or stopping cancer progression.

Anemia is a medical condition characterized by a deficiency in red blood cells or hemoglobin in the blood, leading to a lack of oxygen reaching the body's tissues. Hemoglobin is responsible for carrying oxygen, so any insufficiency can cause fatigue, weakness, and shortness of breath. Anemia can be temporary or long-term, and range from mild to severe. It's important to diagnose and treat anemia to handle any underlying causes and to prevent further health problems.

Aneuploidy refers to an abnormality in the chromosome number in a cell, where there's either an excess or a deficiency of one or multiple chromosomes. This variation from the normal chromosome number (diploid) often leads to various genetic disorders. The most common example is Down syndrome, caused by an extra copy of chromosome 21.

Angiogenesis is a physiological process involving the growth of new blood vessels from pre-existing ones. Predominantly occurring during development, wound healing, and the formation of granulation tissue, it's also a critical step in the transition of tumors from a benign state to a malignant one.

Angiosarcoma is a rare, malignant tumor that originates from endothelial cells, the cells that line the interior surface of blood vessels. It can occur anywhere in the body, but is most commonly found in the skin, breast, liver, spleen, and deep tissue. Due to its aggressive nature, it often leads to a poor prognosis. This tumor presents unique challenges due to its high recurrence rate and resistance to treatment.

Anorexia, medically known as Anorexia Nervosa, is a serious and potentially life-threatening mental health disorder characterized by self-starvation and excessive weight loss. Individuals with this condition have an irrational fear of weight gain and a distorted body image. Treatment typically involves a multidisciplinary approach integrating medical, nutritional, and therapeutic components.

"Anterior Resection" refers to a surgical procedure typically performed on patients with rectal or colon cancer. It involves the removal of the affected part of the rectum or colon and then reattaching the remaining sections to restore digestive function. The procedure involves delicate and complex surgery aiming at retaining bowel function while removing the cancer.

Anti-emetic refers to a type of medication used primarily to prevent or treat nausea and vomiting, symptoms often associated with motion sickness, chemotherapy, radiation, and surgery. Such drugs work by blocking neurotransmitters that trigger these unpleasant sensations. Thus, they are critical in the management of postoperative and chemotherapy-induced nausea and vomiting.

Anti-estrogen refers to a substance that blocks the production or utilization of estrogens, or inhibits their effects. They are commonly used in treatments for hormonal imbalances, such as those related to menopause, or for certain types of hormone-receptor-positive breast cancer.

Antibody-dependent cellular cytotoxicity (ADCC) is a process where immune cells target and destroy cells that are marked by antibodies. This mechanism is crucial for eliminating infected or cancerous cells in the body.

Antibody-drug conjugates (ADCs) are targeted cancer therapeutics that combine an antibody specific to a tumor-associated antigen with a cytotoxic drug designed to kill cancer cells. They allow precise drug delivery, reducing damage to healthy tissues and potentially improving treatment effectiveness and reducing side effects.

Antimetabolites are a class of drugs that inhibit the function of natural metabolites, vital substances for cellular processes, leading to cell destruction. Commonly used in chemotherapy, these drugs target rapidly dividing cancer cells, slowing or stopping their growth. They mimic natural substances, interfering with DNA synthesis, which hinders cell replication.

Aplastic anemia is a rare, serious blood disorder in which the body's bone marrow fails to produce enough new blood cells, leading to a deficiency in all three blood cell types: red blood cells, white blood cells, and platelets. This condition can lead to uncontrolled bleeding, increased susceptibility to infections, and constant fatigue. It can occur at any age, sometimes without known cause.

Apoptosis is a programmed cell death mechanism in the body, operating as a natural process of destructing old, faulty, or harmful cells. It's crucial for maintaining the balance in various bodily functions, from embryonic development to adult homeostasis. It's often subject to research in disease contexts, notably cancer, where apoptosis regulation fails.

Apoptosis inhibitors are substances that prevent or delay the process of apoptosis, which is the programmed cell death essential for maintaining healthy cell turnover and development in the body. These inhibitors can be used in medical treatments to protect cells from premature death, especially in diseases where cell survival is compromised.

Apoptotic bodies are small, membrane-bound vesicles that form when a cell undergoes apoptosis, which is a type of programmed cell death. During this process, the cell's components are broken down and packaged into these bodies, which are then typically engulfed and digested by nearby cells.

An "Aromatase Inhibitor" is a class of drugs used in the treatment of breast cancer and ovarian cancer in postmenopausal women. These drugs work by blocking the enzyme aromatase, which the body utilizes to produce estrogen, a hormone that can stimulate the growth of certain types of cancer cells. Therefore, by reducing estrogen levels, these inhibitors can slow or halt the growth of cancers.

Asbestos is a naturally occurring mineral that has heat-resistant properties. It was widely used in construction and manufacturing due to its strength and fire-resistant qualities. However, its fibers can cause serious health issues, like lung cancer and mesothelioma, when inhaled or ingested, leading to its ban in many countries.

Ascites refers to an abnormal accumulation of fluid in the abdominal cavity, often resulting from severe liver disease, like cirrhosis. The excess fluid causes discomfort and can make breathing difficult. It's usually treated by diet alterations, diuretics, or drainage procedures.

Asparaginase is a therapeutic enzyme used in medical treatment, particularly in the management of acute lymphoblastic leukemia (ALL). It functions by breaking down asparagine, an amino acid crucial for cell growth, thereby inhibiting the proliferation of malignant cells that rely heavily on asparagine.

Astrocytoma is a type of brain tumor that originates from astrocytes, the star-shaped cells that make up the supportive tissue of the brain. These tumors can occur in various parts of the brain and spinal cord. Astrocytomas vary in their level of aggressiveness, ranging from benign (non-cancerous) to malignant (cancerous).

Atypical ductal hyperplasia (ADH) is a non-malignant condition where breast duct cells are multiplying abnormally, creating a higher risk for breast cancer. Although it isn't cancer itself, finding ADH prompts further diagnostic evaluation and possibly more frequent breast cancer screening.

Axillary node dissection is a surgical procedure to remove lymph nodes from the armpit area (axilla) to check for the spread of breast cancer or other diseases.