Welcome to the Rare Classroom, a new series from Patient Worthy. Rare Classroom is designed for the curious reader who wants to get informed on some of the rarest, most mysterious diseases and conditions. There are thousands of rare diseases out there, but only a very small number of them have viable treatments and regularly make the news. This series is an opportunity to learn the basics about some of the diseases that almost no one hears much about or that we otherwise haven’t been able to report on very often.

Eyes front and ears open. Class is now in session.

The disease that we will be learning about today is:

Anal Cancer

What is Anal Cancer?

• Anal cancer is a cancer that appears on the anus, the distal opening of the digestive system
• This cancer is usually classified as a squamous cell carcinoma
  • Other possible types include small cell carcinoma, melanoma, and adenocarcinoma
• Diagnosis is conducted through biopsy and tissue examination
• The number of recognized cases has been increasing since the 1990s, with an average of around 8,300 cases diagnosed each year in the US
  • In 2002, around 30,400 new cases were recognized

How Do You Get It?

• The most important risk factor for anal cancer is infection with human papillomavirus (HPV)
  • Some studies suggest that as many as 90% of cases could be linked to HPV
• Other risk factors include:
  • Smoking
  • Immunosuppression, often from HIV/AIDS
  • A large number of sexual partners
  • Receptive anal sex
  • History of vulval, vaginal, or cervical cancer
  • Women are affected at greater rates than men

What Are the Symptoms?

• Symptoms of anal cancer can include:
  • A lump near or around the anus
  • Pain or pressure from the anus or rectal area
  • Altered bowel habits
  • Anal itching
  • Anal discharge
  • Bleeding from the anus, which can be severe

How Is It Treated?

• Localized cancer can be effectively ablated with minimally invasive techniques, such as infrared photocoagulation
• The most common treatment for local disease includes a combination of chemo and radiation, which has led to improved survival rates and cures in some cases. However, some patients are rendered incontinent after this regimen
• Up to 20% of cases will develop metastases, or cancer spread to other areas of the body
  • Metastatic anal cancer is difficult to treat and chemotherapy is the most common therapy
  • Radiation is also used palliatively to target metastases causing additional symptoms
• Surgical resection of the internal and external anal sphincter, resulting in permanent colostomy, was the most common treatment in the past
• 5-year survival rates vary depending on the case, but the average is around 68% in the US

Where Can I Learn More???

• Check out our cornerstone on this disease here.
• Learn more from the Anal Cancer Foundation.