February 1999
Anal cancer is very similar to cervical cancer in women, and takes the form of tumors or lesions that appear in the anal canal. Studies now show that the rates of anal cancer are much higher in gay men and men who have sex with men (MSM) with HIV. Eight of every 100,000 women will get cervical cancer. Compare this to the numbers for men who have sex with men: 35 of every 100,000 will develop anal cancer. (The risk in the general population is 0.9 per 100,000.)
Estimates of anal cancer in people who are HIV+ are even more staggering. One study shows that HIV+ people are twice as likely to contract anal cancer as HIV-negative men, and that as an AIDS diagnosis approaches, the risk of anal cancer increases further. As the immune system weakens, lesions can develop and progress.
HAART therapy may actually be the reason we are now seeing an increase in anal cancer. Cancer and tumors take several years to fully develop and become noticeable. Before the advent of HAART, people were dying before these lesions and tumors were noticed. Today, as new medicines are keeping people alive longer, new issues like this are now appearing.
And, unlike some other diseases, anal cancer does not seem to improve with better HAART therapy. In one study, 28 men with anal cancer, low CD4 counts, and high viral loads, were given HAART therapy and saw good results virologically. But, only 1 of the 28 experienced a regression of lesions or cancer. This indicates that HAART may have little impact on anal cancer.
Like cervical cancer, anal cancer is caused by a virus, the human papilloma virus (HPV). Initially, the cervix or anal canal develops abnormal, pre-malignant changes called intraepithelial (the superficial layer of the anal canal) neoplasms. These changes gradually worsen and become an invasive cancer. Screening tests are available to look for early changes, a pap smear for women and a similar pap smear of the anal canal for men. This can be preformed easily with a Dacron swab.
If abnormal changes are noted, further investigation and possible surgical excision by a laser may be necessary. Or, there are currently three methods of non-surgical treatment:
Because of this data it is very important for all men who have sex with men to add anal screens to their health check-ups.
| Please note: Knowledge about HIV changes rapidly. Note the date of this summary's publication, and before treating patients or employing any therapies described in these materials, verify all information independently. If you are a patient, please consult a doctor or other medical professional before acting on any of the information presented in this summary. For a complete listing of our most recent conference coverage, click here. |
Back to The Body's Retroviruses Conference Coverage Main Page.