Actress Marcia Cross (“Desperate Housewives”) and her doctors revealed Wednesday that they believe her battle with anal cancer was caused by the same human papillomavirus (HPV) that led to her husband Tom Mahoney’s throat cancer.

HPV is the most common sexually transmitted disease, infecting some 79 million Americans. In its benign form, it goes undetected, often subdued by our body’s immune system. In some cases, though, it produces warts. And, if left untreated, more extreme strains of the virus could cause cancer.

But the risks extend beyond the anus.

HPV can be transmitted through a number of sex acts, which means that any body part involved in sexual intercourse is at risk — including the cervix, vagina, vulva, penis and throat.

Dr. Daniel Popowich, assistant professor of surgery specializing in colorectal surgeries at Mt. Sinai, says “HPV virus is ubiquitous … but that doesn’t mean it will lead to cancer.”

Of the more than 100 strains of the virus, he explains, only some of them are known to promote cancer cell growth. Popowich only recalls one case of anal HPV that led to cancer over the course of his career.

Popowich says high-risk patients — those who engage in anal sex or suffer from immuno-suppressive diseases such as HIV — may be ordered a swab test, much like a pap smear in women, during a routine checkup. If lab results detect HPV, surgeons like Popowich will remove the cancerous growth, which “can significantly reduce (the virus’) transition to cancer.”

If cancer does develop, symptoms usually start as an itchy bump or bleeding, which many patients mistake for hemorrhoids, says Popowich, who adds that “bleeding is always a reason to see your doctor.” Anal cancer is treated “conventionally” with chemotherapy and radiation and doesn’t usually require surgery, i.e. a colostomy.

The treatment is “curative,” according to Popowich: “They get to keep their tush and normal bathroom habits.”

Popowich says Cross sharing her story is an important effort to “destigmatize the embarrassment” of anal illness.

“This happens to people who you look up to,” he says. “Anyone can be affected.”

The Centers for Disease Control estimates HPV is behind about 90% of anal and cervical cancers, 70% of vaginal and vulvar cancers, 70% of oropharyngeal (throat and pharynx) cancers and 60% of penile cancers.

Apart from regular screenings and being alert to changes in you body, Popowich also strongly recommends the Gardasil vaccine, which protects against several cancer-causing strains of HPV, and widely available to men and women aged 11 to 45.

This isn’t the only high-profile case of cancer as a result of sex.

In 2013, Michael Douglas blamed his tongue cancer on oral sex with women over the decades — suggesting the latent HPV cells in vaginas had traveled to his mouth.

He later walked back those comments amid reports that his wife, Oscar-winner Catherine Zeta Jones, was less than pleased.

In her newfound mission to increase awareness of anal cancer, Cross has one piece of advice.

“Having woken up to its importance, I am now a big fan of the anus!” she tells People magazine. “If something doesn’t feel right, listen to your body and talk to your doctor. Don’t let it go. It’s a very curable cancer if caught early, which mine was.”