Anal cancer is not something you often read or hear about in the daily news.

Maybe it’s too taboo to talk about this part of the body. Actress Farrah Fawcett did not mention what type of cancer she is battling, but, according to reports, the 59-year-old actress has a rare form of anal cancer.

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The cancer itself is also rare, affecting more than 4,600 people each year, according to the American Cancer Society (ACS). It isn’t top of mind. However, the number of cases of the cancer has remained at a steady number since last year, which means, it has not gone away.

In 2006, there were approximately 4,660 new cases of anal cancer in the U.S. and around 660 deaths, according to the ACS. This year, more than 4,600 cases are expected.

Likewise, oral cancer, that is cancers of the throat, tonsils and back of the tongue, are not cancers commonly discussed. In fact, of the 45,000 new cases of head and neck cancers expected this year, only 10,000 will affect the back of throat area. Oral cancer is on the decline in America, except in men over the age of 45.

The culprit in the rise in both oral and anal cancers in men is the human papillomavirus (HPV), a sexually transmitted disease that can form in the genital area of men and women including the skin of the penis, vulva (area outside the vagina), anus or in the linings of the vagina, cervix or rectum.

The number of HPV cases, while still high in women, is increasing in the male community, particularly in gay men, according to Dr. Robert Mayer, vice chairman of academic affairs at the Dana-Farber Cancer Institute in Boston.

One of the main factors leading to HPV and eventually, anal cancer, is engaging in anal sex. In addition to anal sex, other risk factors include having multiple sex partners, frequent anal redness or soreness and smoking.

The cancer may be mistaken for skin cancer, since the tumors can initially form on the skin area outside of the anus, which is the same skin that is on the buttocks.

“Virally, it’s a condition that is sexually transmitted,” said Mayer. “It’s the same virus that causes anal cancer. For many years, it was associated with venereal warts, giving a connotation that it was related to some form of sexual activity. For years, it occurred mostly with women, but now it’s occurring with a larger percentage of (gay) men. It’s related to sexual practices and the passage of virals in the anus.”

Oral Cancer

Although HPV and cervical cancer can be readily diagnosed in women through annual pap smears, men don’t normally undergo any sort of tests that would detect oral HPV or throat cancer, said Dr. Erich M. Sturgis, of the University of Texas M. D. Anderson Cancer Center in Houston.

“Cervical cancer is so well established,” he said. “In fact, well before we had the HPV vaccination, we were able to prevent cervical cancer and catch cervical cancer early because of the good screening methods. We don’t have the same kind of methods of screening for cancers of the throat and oral HPV.”

Men also are a “hidden reservoir” for the virus and can pass the disease onto their female partners, Sturgis said.

It’s for these reasons that Sturgis believes research is needed to determine whether the HPV vaccine, sold under the brand Gardasil and currently available to young girls in the U.S., is effective for boys.

“I’m aware that drug companies are studying their vaccinations in men,” he said. “And that’s hopefully going to provide evidence that the vaccine is effective in preventing the virus in men.”

Sturgis said some of the studies of the HPV vaccine and men are focused on men who are at high risk for anal cancer.

“It’s a group that is more likely to get (regular) anal or genital swabs and, therefore, it’s easier to track the disease,” he said.

In the meantime, men and women should view cervical, oral and anal cancers as sexually transmitted diseases, or at least understand that these potentially deadly cancers are more often than not caused by a sexually transmitted disease, and protect themselves, Sturgis said.

“Condoms will protect against the virus somewhat,” he said. “But women should be examined each year, and if they do have an abnormal pap smear, they should be treated and make sure their partners are treated.”