Many management options for cancer exist including: chemotherapy, radiation therapy, surgery, immunotherapy, monoclonal antibody therapyand other methods. Which are used depends upon the location and grade of the tumor and the stage of the disease, as well as the general state of a person's health. Experimental cancer treatments are also under development.
Complete removal of the cancer without damage to the rest of the body is the goal of treatment. Sometimes this can be accomplished by surgery, but the propensity of cancers to invade adjacent tissue or to spread to distant sites by microscopic metastasis often limits its effectiveness. The effectiveness of chemotherapy is often limited by toxicity to other tissues in the body. Radiation can also cause damage to normal tissue.
Because "cancer" refers to a class of diseases,[75][76] it is unlikely that there will ever be a single "cure for cancer" any more than there will be a single treatment for all infectious diseases.[77] Angiogenesis inhibitors were once thought to have potential as a "silver bullet" treatment applicable to many types of cancer, but this has not been the case in practice.[78]
Prognosis
Cancer has a reputation for being a deadly disease. While this certainly applies to certain particular types, the truths behind the historical connotations of cancer are increasingly being overturned by advances in medical care. Some types of cancer have a prognosis that is substantially better than nonmalignant diseases such as heart failure and stroke.
Progressive and disseminated malignant disease has a substantial impact on a cancer patient's quality of life, and many cancer treatments (such as chemotherapy) may have severe side-effects. In the advanced stages of cancer, many patients need extensive care, affecting family members and friends. Palliative care solutions may include permanent or "respite" hospice nursing.
Emotional impact
Many local organizations offer a variety of practical and support services to people with cancer. Support can take the form of support groups,counseling, advice, financial assistance, transportation to and from treatment, films or information about cancer. Neighborhood organizations, local health care providers, or area hospitals may have resources or services available.
Counseling can provide emotional support to cancer patients and help them better understand their illness. Different types of counseling include individual, group, family, peer counseling, bereavement, patient-to-patient, and sexuality.
Many governmental and charitable organizations have been established to help patients cope with cancer. These organizations are often involved in cancer prevention, cancer treatment, and cancer research.
Epidemiology
As of 2004, worldwide cancer caused 13% of all deaths (7.4 million). The leading causes were: lung cancer(1.3 million deaths/year), stomach cancer (803,000 deaths), colorectal cancer (639,000 deaths), liver cancer(610,000 deaths), and breast cancer (519,000 deaths).[80] Greater than 30% of cancer is preventable via avoiding risk factors including: tobacco, overweight or obesity, low fruit and vegetable intake, physical inactivity, alcohol, sexually transmitted infections, and air pollution.[30]
In the United States, cancer is responsible for 25% of all deaths with 30% of these from lung cancer. The most commonly occurring cancer in men is prostate cancer (about 25% of new cases) and in women isbreast cancer (also about 25%). Cancer can occur in children and adolescents, but it is uncommon (about 150 cases per million in the U.S.), with leukemia being the most common.[81] In the first year of life theincidence is about 230 cases per million in the U.S., with the most common being neuroblastoma.[82]
In the developed world, one in three people will develop cancer during their lifetimes. If all cancer patients survived and cancer occurred randomly, the lifetime odds of developing an second primary cancer would be one in nine.[83] However, cancer survivors have an increased risk of developing a second primary cancer, and the odds are about two in nine.[83] About half of these second primaries can be attributed to the normal one-in-nine risk associated with random chance.[83] The increased risk is believed to be primarily due to the same risk factors that produced the first cancer, such as the person's genetic profile, alcohol and tobacco use, obesity, and environmental exposures, and partly due, in some cases, to the treatment for the first cancer, which might have included mutagenic chemotherapeutic drugs or radiation.[83] Cancer survivors may also be more likely to comply with recommended screening, and thus may be more likely than average to detect cancers.[83]
History
Today, the Greek term carcinoma is the medical term for a malignant tumor derived from epithelial cells. It is Celsus who translated carcinosinto the Latin cancer, also meaning crab. Galen used "oncos" to describe all tumours, the root for the modern word oncology.[84]
Hippocrates described several kinds of cancers. He called benign tumours oncos, Greek for swelling, and malignant tumours carcinos, Greek for crab or crayfish. This name comes from the appearance of the cut surface of a solid malignant tumour, with "the veins stretched on all sides as the animal the crab has its feet, whence it derives its name"[85] (see picture). He later added the suffix -oma, Greek for swelling, giving the name carcinoma. Since it was against Greek tradition to open the body, Hippocrates only described and made drawings of outwardly visible tumors on the skin, nose, and breasts. Treatment was based on the humor theory of four bodily fluids (black and yellow bile, blood, and phlegm). According to the patient's humor, treatment consisted of diet, blood-letting, and/or laxatives. Through the centuries it was discovered that cancer could occur anywhere in the body, but humor-theory based treatment remained popular until the 19th century with the discovery ofcells.
The oldest known description and surgical treatment of cancer was discovered in Egypt and dates back to approximately 1600 B.C. ThePapyrus describes 8 cases of ulcers of the breast that were treated by cauterization, with a tool called "the fire drill." The writing says about the disease, "There is no treatment."[86]
Another very early surgical treatment for cancer was described in the 1020s by Avicenna (Ibn Sina) in The Canon of Medicine. He stated that the excision should be radical and that all diseased tissue should be removed, which included the use of amputation or the removal of veinsrunning in the direction of the tumor. He also recommended the use of cauterization for the area being treated if necessary.[87]
In the 16th and 17th centuries, it became more acceptable for doctors to dissect bodies to discover the cause of death. The German professorWilhelm Fabry believed that breast cancer was caused by a milk clot in a mammary duct. The Dutch professor Francois de la Boe Sylvius, a follower of Descartes, believed that all disease was the outcome of chemical processes, and that acidic lymph fluid was the cause of cancer. His contemporary Nicolaes Tulp believed that cancer was a poison that slowly spreads, and concluded that it was contagious.[88]
The first cause of cancer was identified by British surgeon Percivall Pott, who discovered in 1775 that cancer of the scrotum was a common disease among chimney sweeps. The work of other individual physicians led to various insights, but when physicians started working together they could make firmer conclusions.
With the widespread use of the microscope in the 18th century, it was discovered that the 'cancer poison' spread from the primary tumor through the lymph nodes to other sites ("metastasis"). This view of the disease was first formulated by the English surgeon Campbell De Morgan between 1871 and 1874.[89] The use of surgery to treat cancer had poor results due to problems with hygiene. The renowned Scottish surgeon Alexander Monro saw only 2 breast tumor patients out of 60 surviving surgery for two years. In the 19th century, asepsis improved surgical hygiene and as the survival statistics went up, surgical removal of the tumor became the primary treatment for cancer. With the exception of William Coley who in the late 1800s felt that the rate of cure after surgery had been higher before asepsis (and who injected bacteria into tumors with mixed results), cancer treatment became dependent on the individual art of the surgeon at removing a tumor. During the same period, the idea that the body was made up of various tissues, that in turn were made up of millions of cells, laid rest the humor-theories about chemical imbalances in the body. The age of cellular pathology was born.
When Marie Curie and Pierre Curie discovered radiation at the end of the 19th century, they stumbled upon the first effective non-surgical cancer treatment. With radiation also came the first signs of multi-disciplinary approaches to cancer treatment. The surgeon was no longer operating in isolation, but worked together with hospital radiologists to help patients. The complications in communication this brought, along with the necessity of the patient's treatment in a hospital facility rather than at home, also created a parallel process of compiling patient data into hospital files, which in turn led to the first statistical patient studies.
A founding paper of cancer epidemiology was the work of Janet Lane-Claypon, who published a comparative study in 1926 of 500 breast cancer cases and 500 control patients of the same background and lifestyle for the British Ministry of Health. Her ground-breaking work on cancer epidemiology was carried on by Richard Doll and Austin Bradford Hill, who published "Lung Cancer and Other Causes of Death In Relation toSmoking. A Second Report on the Mortality of British Doctors" followed in 1956 (otherwise known as the British doctors study). Richard Doll left the London Medical Research Center (MRC), to start the Oxford unit for Cancer epidemiology in 1968. With the use of computers, the unit was the first to compile large amounts of cancer data. Modern epidemiological methods are closely linked to current concepts of disease and public health policy. Over the past 50 years, great efforts have been spent on gathering data across medical practise, hospital, provincial, state, and even country boundaries, as a way to study the interdependence of environmental and cultural factors on cancer incidence.
Cancer patient treatment and studies were restricted to individual physicians' practices until World War II, when medical research centers discovered that there were large international differences in disease incidence. This insight drove national public health bodies to make it possible to compile health data across practises and hospitals, a process that many countries do today. The Japanese medical community observed that the bone marrow of victims of the atomic bombings of Hiroshima and Nagasaki was completely destroyed. They concluded that diseased bone marrow could also be destroyed with radiation, and this led to the discovery of bone marrow transplants for leukemia. Since World War II, trends in cancer treatment are to improve on a micro-level the existing treatment methods, standardize them, and globalize them as a way to find cures through epidemiology and international partnerships.
Research
Cancer research is the intense scientific effort to understand disease processes and discover possible therapies. The improved understanding ofmolecular biology and cellular biology due to cancer research has led to a number of new, effective treatments for cancer since President Nixon declared "War on Cancer" in 1971. Since 1971 the United States has invested over $200 billion on cancer research; that total includes money invested by public and private sectors and foundations.[90] Despite this substantial investment, the country has seen a five percent decrease in the cancer death rate (adjusting for size and age of the population) between 1950 and 2005.[91]
Leading cancer research organizations and projects include the American Association for Cancer Research, the American Cancer Society(ACS), the American Society of Clinical Oncology, the European Organisation for Research and Treatment of Cancer, the National Cancer Institute, the National Comprehensive Cancer Network, and The Cancer Genome Atlas project at the NCI.
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