Everything you need to know about anal cancer

Including how hard it is to talk about.

Maija Kappler 5 minute read August 9, 2021

Like many other cancers, anal cancer is usually treated with chemotherapy and radiation Getty

Some illnesses are easier to talk about than others. Disclosing certain cancer diagnoses, for instance, will generally elicit people’s compassion and understanding. Others, like lung cancer, are often judged.

And then there’s anal cancer.

Anything related to the anus is, frankly, uncomfortable to talk about. “Feelings of stigma may be related to the anus being associated with the elimination of bodily waste and the risk factors associated with anal cancer, including HPV and sexual activity,” says the Anal Cancer Foundation on their website. “These factors may contribute to some people’s feelings of embarrassment—but they shouldn’t!”

Taboo and stigma around anal issues can make it hard for people to talk about an anal cancer diagnosis. It’s also “prevented equitable resources and funding for support, research and better treatments,” the group says.

Causes and risk factors
There’s still not enough research to state it definitively, but most cases of anal cancer are thought to be caused by the sexually-transmitted infection human papillomavirus (usually called HPV), according to the Mayo Clinic. HPV is the most common STI — so common that most people who have sex will get some form of HPV at some point in their lives, Planned Parenthood says. HPV is usually harmless, but in addition to anal cancer, it can sometimes cause cervical cancer. The kind that can lead to anal cancer often involves genital warts.

Some of the other risk factors for anal cancer include smoking, being on medication that suppresses the immune system, having had cervical, vaginal or vulvar cancers in the past, and having receptive anal sex. It’s usually more common in women than men. Black men, though, are more likely to be diagnosed with anal cancer than Black women.

The people diagnosed with anal cancer are usually over 50, although it’s becoming increasingly common in young people. Black people between the ages of 23 and 38 and white women are the fastest-growing demographics for squamous cell carcinoma, the most common type of anal cancer, according to research from 2019.

The most recent Canadian statistics show that anal cancer is relatively rare: 585 Canadians were diagnosed in 2016, and 141 people died from the illness in 2017.

But that same 2019 study found that squamous cell carcinoma, the most common form of anal cancer, has risen steadily over the last few decades: diagnoses have gone up 2.7 per cent every year between 2001 and 2016. Deaths from anal cancer were even more common, rising 3.1 per cent every year.

There are a number of kinds of anal cancer:

  • Squamous cell carcinoma is the most common, accounting for ten out of 10 cases, according to the American Cancer Society. It involves tumours in the cells that line the canal of the anus.
  • Adenocarcinoma affects the glands around the anus. It’s fairly rare.
  • Basal cell carcinoma usually affects skin that gets lots of sun exposure. For that reason, it’s quite rare as an anal caner.
  • Bowen’s disease (also called squamous cell carcinoma in situ) involves cells on the surface tissue of the anal surface, but not the deeper layers. It’s also quite rare in anal cancer.

Signs and symptoms
Anal cancer can be hard to detect because tumours are generally very small in the early stages, according to the Canadian Cancer Society. Possible warning signs include:

  • Anal bleeding
  • HPV infection that causes genital warts
  • Pain, pressure or itching around the anus
  • Unusual discharge or bowel movements
  • Lumps or swelling around the anus or the groin

Like many other cancers, anal cancer is usually treated with chemotherapy and radiation. If those don’t work, doctors may attempt surgery.

Again, like many other cancers, it’s highly treatable if it’s detected early. That happens in about half of all cases, according to WebMD. Squamous cell carcinoma, the most common type by far, has a better prognosis than the rarer kinds of cancers.

The size of the tumour makes a difference as well: tumours smaller than 2 cm generally have a good prognosis, while tumours bigger than 5 cm are much riskier.

Recent Canadians statistics aren’t available, but in the U.S. people with anal cancer have a five-year, relative survival rate of about 69 per cent after their diagnosis.

Fighting stigma
While the stigma around this kind of cancer is real, there’s been a concerted effort to fight it. Heading that initiative is “Desperate Housewives” actress Marcia Cross, who was diagnosed with anal cancer in 2017 and went into remission the next year.

“I wasn’t interested in becoming the anal cancer spokesperson. I wanted to move on with my career and my life,” Cross told Coping, a magazine for people living with cancer. “But as I was going through it, I read repeatedly about people who were ashamed, who were hiding, who were lying about their diagnosis. And on the other side, how doctors were not comfortable talking about it.”

She said that kind of discomfort meant patients weren’t getting the vital aftercare information they needed, like how scar tissue could develop on the vagina following radiation.

“I just saw how, oh my gosh, we are so behind on all of this because it’s our anuses,” she went on.

“I just have a lot of respect for this tiny, little two inches that makes our lives livable and pleasant. I really think to destigmatize it is the way to go. It’s just silly … We all have one. It’s nothing to be embarrassed or ashamed of.”

For more information on anal cancer, support or to connect with other patients, visit the Canadian Cancer Society or Wellspring.