If you continue to use this site, then you acknowledge our use of tracking technologies. For additional information, review our Privacy Policy. Previously, this cancer had been known to affect primarily elderly men of Mediterranean and Jewish descent, who might live for many years with the disease. Now, it was occurring in otherwise young, healthy men with deadly consequences.
This was the first announcement, in the mainstream press, of what would become the AIDS epidemic. Often appearing as bright purple spots, KS lesions were one of the main symptoms for which the affected individuals sought help from doctors.
Doctors, having few other options at their disposal, often treated their new cancer patients with chemotherapy. It would not be long before AIDS shed its link to cancer, as opportunistic infections eclipsed KS as the major sign of the condition, and as scientists began to understand both as resulting from a mysteriously crippled immune system.
But this early connection to cancer had far-reaching implications for the course of the epidemic. The epidemic of cancer among gay men seemed to suggest that cancer might have a traceable cause—one that, if identified, could help lead to a cure for cancer in general.
To fully appreciate the role that cancer played in AIDS, we have to go back to the s, when researchers became convinced that cancer had a viral cause. A viral cause of cancer was first proposed back in by a biologist named Peyton Rous at the Rockefeller Institute, who provided strong evidence that a virus transmitted cancer in chickens. But the wider scientific community was skeptical, and his research was largely ignored for the next 50 years.
It was not until the s that interest in the idea of cancer viruses really took off, following the discovery by Ludwik Gross at the Bronx Veteran Affairs Medical Center that viruses can cause leukemia in mice. See Timeline of Progress. These discoveries unleashed an explosion of research. In , the National Cancer Institute NCI inaugurated its Special Virus Cancer Program, with the goal of identifying human cancer viruses similar to the ones that cause cancer in chickens and mice.
The hope was that by pinpointing cancer viruses in humans it would be possible to vaccinate against them and prevent cancer. Despite more than a decade of research, however, the effort largely failed, and by the late s, many researchers had soured on the idea.
When the program was terminated in , a medical consensus had emerged that viruses were not a significant cause of human cancers. Enter AIDS. Suddenly, cancer was appearing in clusters of interlinked people, suggesting that a transmissible biological agent, such as a virus, was the cause. Because viruses were known to cause cancer in some laboratory animals, it was a natural step to suspect a virus in these human cases.
And sure enough, people with AIDS were found to be infected with quite a few different viruses, including cytomegalovirus, hepatitis B, and herpes.
But these garden-variety viruses were nothing new. Why would they start causing an epidemic of cancer now? Among the few scientists still pursuing cancer virus research at this time was Robert Gallo, M. Gallo had been searching for viral causes of cancer since the early s, when, as a practicing oncologist, he became interested in the causes of childhood leukemia.
Even after the intellectual tide turned against him, he continued to work on the topic. He discovered a virus, which he named human T lymphotropic virus HTLV-I , that was linked to a rare form of lymphoma in people.
As its name suggests, the virus was specific for immune cells called T cells, which it infects and causes to replicate uncontrollably. Not only that, the virus was a retrovirus—the same sort of virus that Rous and Gross had found causes cancer in animals, and which had prompted the search for human cancer viruses in the first place. This work was followed the next year, by the discovery of a second human retrovirus, HTLV-II, linked to a different cancer. Symptoms of CNS lymphoma can include seizures, facial paralysis, confusion, memory loss, and feeling tired.
Cervical cancer is a cancer of the cervix, the lower part of the uterus womb. Like Kaposi sarcoma, cervical cancer is strongly linked to infection with a virus. In this case, the virus is the human papilloma virus HPV. HPV can be spread from person to person through skin-to-skin contact, including through sex. CIN is the growth of abnormal, pre-cancerous cells in the cervix. Over time, CIN can progress to invasive cervical cancer, in which the cancer cells grow into deeper layers of the cervix.
CIN must be treated to keep it from invading. This is done by removing or destroying the outer layers of cervical cells. The chance of the disease coming back after treatment is high, especially in women with very low CD4 helper T cell counts. HIV-infected women with invasive cervical cancer and good immune function tend to do well with surgery and the same treatments that women without HIV get. Other types of cancer are also more likely to develop in people with HIV than in people who are not infected, including:.
Some of these cancers have been linked to infections with different viruses. These viruses can cause cancer in people with and without HIV, but the risk might be higher in people with HIV because their immune systems are less able to control the viral growth. For example, anal cancer and some mouth and throat cancers are linked to infection with HPV, the same virus that causes cervical cancer. Liver cancer is known to be more common in people infected with the hepatitis B or C viruses.
Some types of lymphoma have been linked with viral infections as well. For some cancers, the higher risk in people who have HIV may be because of other risk factors these people are more likely to have, rather than the HIV infection itself. For example, mouth, throat, and lung cancers are strongly linked with smoking, which is more common in people with HIV, and the link with HIV becomes much weaker if smoking status is taken into account.
Cancers of the liver, mouth, and throat as well as some other cancers are linked with heavy alcohol use, which is also more common in people with HIV.
Vaccines are now available to help protect children and young adults against infection from the main cancer-causing HPV types. These vaccines are approved for use in females and males and are given as a series of injections shots. The vaccines can only be used to help prevent HPV infection — they do not stop or help treat an existing infection. To be most effective, the vaccine series should be given before a person becomes sexually active has sex with another person.
See HPV Vaccines for more on this. EBV is a type of herpes virus. Most people in the United States are infected with EBV by the end of their teen years, although not everyone develops the symptoms of mono. As with other herpes virus infections, EBV infection is life-long, even though most people have no symptoms after the first few weeks. EBV infects and stays in certain white blood cells in the body called B lymphocytes also called B cells.
It may also be linked to Hodgkin lymphoma and some cases of stomach cancer. Overall, very few people who have been infected with EBV will ever develop these cancers. But this number is much higher in some other countries, where both viral hepatitis and liver cancer are much more common. Some research also suggests that long-term HCV infection might be linked with some other cancers, such as non-Hodgkin lymphoma.
They can also be passed on through blood transfusions, but this is rare in the United States because donated blood is tested for these viruses. Of the 2 viruses, infection with HBV is more likely to cause symptoms, such as a flu-like illness and jaundice yellowing of the eyes and skin.
Most adults recover completely from HBV infection within a few months. Only a very small portion of adults go on to have chronic HBV infections, but this risk is higher in young children.
People with chronic HBV infections have a higher risk for liver cancer. HCV is less likely to cause symptoms than HBV, but it is more likely to cause chronic infection, which can to lead to liver damage or even cancer.
An estimated 3. To help find some of these unknown infections, the US Centers for Disease Control and Prevention CDC recommends that all people born between and as well as some other people at high risk get blood tests to check for HCV.
Once an infection is found, treatment and preventive measures can be used to slow liver damage and reduce cancer risk. Both hepatitis B and C infections can be treated with drugs. Treating chronic hepatitis C infection with a combination of drugs for at least a few months can get rid of HCV in many people. A number of drugs can also be used to help treat chronic hepatitis B. This includes people infected with HIV, men who have sex with men, injection drug users, people in certain group homes, people with certain medical conditions and occupations such as health care workers , and others.
Known routes of spread include:. HIV is not spread by insects, through water, or by casual contact such as talking, shaking hands, hugging, coughing, sneezing, or from sharing dishes, bathrooms, kitchens, phones, or computers. It is not spread through saliva, tears, or sweat. This might let some other viruses, such as HPV, thrive, which might lead to cancer.
Many scientists believe that the immune system is also important in attacking and destroying newly formed cancer cells. A weak immune system might let new cancer cells survive long enough to grow into a serious, life-threatening tumor. HIV infection has been linked to a higher risk of developing Kaposi sarcoma and cervical cancer. The CDC recommends that everyone between the ages of 13 and 64 be tested for HIV at least once as part of their routine health care.
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