Cancer

A malignant neoplasm or tumour in nay part of the body.


A wide variety of diseases characterised by uncontrolled growth of tissue.


The name given to a group of diseases that are characterized by uncontrolled cellular growth (e.g., formation of tumor).


A malignant tumour of growth that expands locally by invasion and systemically by metastasis.


Various types of malignant cells that multiply out of control.


A group of diseases in which there is unrestrained growth of abnormal cells in tissues and organs of the body.


A neoplasm or tumor.


A group of diseases characterized by abnormal growth of cells which, because the growth is uncontrolled, subsumes the normal functions of vital organs and tissues.


A general name for a wide variety of diseases that have in common unchecked growth of the cells in one or more parts of the body. The resulting abnormal growths, called tumors or neoplasms, crowd out normal cells and eventually kill the tissue or organs involved. Any part of the body can be affected, not just the major organs, such as the heart and lungs; cancer often affects the skin; the lymphatic system, as in Hodgkin’s disease; and the bone marrow.


Abnormal, malignant growth of cells that invade nearby tissues and often spread (metastasize) to other sites in the body, interfering with the normal function of the affected sites. Although the basic cause of cancer remains unknown, most forms of cancer can be traced to a specific causal or precipitating factor (e.g., cigarette smoking, exposure to cancer-producing chemicals (carcinogens) or ionizing radiation, or overexposure to the sun); viruses are associated with some cancers and genetic (familial) susceptibility plays a role in certain forms or the disease. The incidence of different types of cancer varies greatly with age, sex, ethnic group, and geographic location. In the United States cancer is second to heart disease as a cause of death, with breast cancer and lung cancer leading the statistics. Older persons are much more prone to cancer (at age 25, the probability of developing cancer within 5 years is 1 in 700, at age 65, it is 1 in 14). The parts of the body most often affected by cancer are the breast, lungs, colon, uterus, oral cavity, and bone marrow. Major signs of cancer include a change in bladder or bowel habits; a sore that does not heal; a persistent cough or hoarseness; unusual bleeding or discharge; thickening or lump in the breast or other part of the body; indigestion or difficulty in swallowing; unexplained loss of weight; and change in a wart or mole. The treatment of cancer may involve surgery, the irradiation of affected parts, and/or chemotherapy. The prognosis depends on the type and site of the cancer, the promptness of initial treatment, and other factors; about one-third of patients with newly diagnosed cancers are ultimately permanently cured.


Any of a group of diseases characterized by an uncontrolled, abnormal growth of cells that can spread throughout the body. The terms malignancy and neoplasia are often used interchangeably with cancer. Cancer is thought to develop from a single cell or a small set of cells after changes have occurred in their DNA, the genetic material that instructs cells how to behave. Some cancers result from inherited genetic abnormalities, and others are triggered by carcinogens, environmental agents capable of causing genetic mutations. Sometimes, viruses interact with genes in cells and make them more likely to become cancerous. Often, the reason that a cell becomes cancerous is unknown.


Any malignant tumor, including carcinoma and sarcoma. It arises from the abnormal and uncontrolled division of cells that then invade and destroy the surrounding tissues. Spread of cancer cells (‘metastasis) may occur via the bloodstream or the lymphatic channels or across body cavities such as the pleural and peritoneal spaces, thus setting up secondary tumors at sites distant from the original tumor. Each individual primary tumor has its own pattern of local behavior and metastasis; for example, bone metastasis is very common in breast cancer but very rare in cancer of the ovary.


The general term used to refer to a malignant tumour, irrespective of the tissue of origin. ‘Malignancy’ indicates that (i) the tumour is capable of progressive growth, unrestrained by the capsule of the parent organ, and/or (ii) that it is capable of distant spread via lymphatics or the bloodstream, resulting in development of secondary deposits of tumour known as ‘metastases’. Microscopically, cancer cells appear different from the equivalent normal cells in the affected tissue. In particular they may show a lesser degree of differentiation (i.e. they are more ‘primitive’, features indicative of a faster proliferative rate and disorganised alignment in relationship to other cells or blood vessels. The diagnosis of cancer usually depends upon the observation of these microscopic features in biopsies, i.e. tissue removed surgically for such examination.


Malignant neoplasia marked by the uncontrolled growth of cells, often with invasion of healthy tissues locally or throughout the body. Cancer is the second leading cause of death in the U.S., after the cardiovascular diseases. In 2006 the American Cancer Society reported that 564,830 Americans died of cancer, and twice that number were newly diagnosed with one form or another of the disease. The most common cancers in the U.S. are lung, breast, colon, prostate,  and skin. Because most cancers occur in patients who are 65 or older, the incidence of cancer is expected to increase as the population ages. More than 200 kinds of cancer have been identified. Cancers that arise from epithelial tissues are called carcinomas; from mesenchymal tissues, sarcomas; from glial cells, gliomas; from lymphatic cells, lymphomas; from blood-forming cells, leukemias; from pigmented skin cells, melanomas; from plasma cells, myelomas.


A group of over 100 different diseases, all characterized by abnormal cell growth and replication. It has a lethal tendency to invade and destroy normal tissues and spread to other parts of the body. While cancer is the second leading cause of death in the United States, about half of cancers can be cured.


Group of diseases characterized by uncontrolled growth and spread of abnormal cells into malignant tumors.


An umbrella category of around 200 diseases involving endogenous abnormal cells developing, proliferating, and then invading the body’s healthy tissues.


The unbridled proliferation of aberrant cells that have undergone mutations from their original healthy tissues.


A multitude of illnesses characterized by the abnormal and uncontrolled proliferation of cells within bodily organs or tissues. Malignant growths, known as cancerous tumors, have the potential to manifest in any bodily tissue, although their occurrence is most frequently observed in vital organs like the lungs, breasts, intestines, skin, stomach, or pancreas. Furthermore, cancerous tumors may emerge in the nasal sinuses, testes or ovaries, as well as the lips or tongue. The development of cancers can also transpire in the bone marrow, where blood cells are generated, and within the lymphatic system, muscles, or bones.


Distinguishing themselves from benign (noncancerous) growths, cancers exhibit the propensity to disseminate and infiltrate adjacent normal tissue. These tumors have the capacity to impede the function of hollow organs, such as those found within the digestive tract. Additionally, they possess the ability to impair nerves and corrode bone. Cancer cells can also disseminate via the bloodstream or the lymphatic system, giving rise to secondary tumors known as metastases in other organs.


The genesis of tumor-inducing cells occurs when alterations take place in the oncogenes, which are responsible for governing cell growth and proliferation. These changes give rise to a cluster of aberrant cells that exhibit accelerated division compared to their normal counterparts. Furthermore, these cells lose their specialized function and fail to differentiate properly. Consequently, they may evade the usual regulation exerted by hormones and nerves.


Cancer can arise from various factors, including environmental influences like sunlight exposure and pollutants, consumption of alcohol, dietary elements, and notably, smoking, which stands as the primary causative agent for a greater number of cancers compared to any other factor. Each of these factors has the potential to elicit significant alterations in the cells of individuals who possess a susceptibility to developing cancer. Furthermore, certain cancers may also have a hereditary component, making individuals more prone to their occurrence.


The manifestation of cancer symptoms is contingent upon factors such as the specific location of the tumor, the tissue from which it originates, and the extent of its growth. These symptoms can either directly arise as a result of the tumor’s presence, such as the presence of lumps or changes in the skin, or they may ensue from the disruption of vital organ function or blockage within the body caused by the tumor. Additionally, unexplained weight loss is a common occurrence in various types of cancer.


Screening tests are increasingly employed to identify early indications of specific cancer types in individuals deemed to be at risk. Detecting cancer in its early stages significantly enhances the likelihood of successful treatment, which is why screening initiatives for breast cancer, cervical cancer, and colorectal cancer have effectively reduced mortality rates associated with these tumors. The diagnosis of cancer subsequent to the manifestation of symptoms typically involves a comprehensive physical examination, followed by confirmation through biopsy (the extraction of an abnormal tissue sample for microscopic analysis) and imaging tests.


The identification of cancer involves the utilization of four key procedural approaches: cytology (cell) tests, imaging methodologies, chemical examinations, and direct inspection.


Presently, numerous forms of cancer can be effectively treated, typically employing a combination of surgical interventions, radiotherapy, and pharmaceutical agents with anticancer properties. For specific information regarding a particular cancer type, please consult the corresponding article pertaining to the respective organ.


A loosely used term to describe any type of malignant growth. Every organ in the body consists of specialized cells, each with distinct functions and recognizable shapes under a microscope. Cancerous changes occur when, for reasons yet unexplained, certain organ cells suddenly start rapidly multiplying in a different form. Since cancer cells lack a specific function, they cannot perform any useful tasks and eventually replace all functioning cells in the organ. Cancer can spread throughout the body through direct invasion or by entering the bloodstream and lymphatic system, circulating as emboli. Some cancers respond to treatment with deep x-rays, radium, drugs, or hormones. In the future, there is hope that cancer can be controlled by injecting an as-yet-unknown chemical that prevents normal cells from acquiring this malignant capability for rapid multiplication.


 


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