|
High
Resolution Anoscopy Findings for Men Who Have Sex with Men
In
men, the occurrence of anal squamous cell
carcinoma (SCC) is strongly associated with a
history of receptive anal intercourse and anogenital
human papillomavirus (HPV) infection
.
Concurrent
HIV infection has increased the incidence of
anal SCC in HIV-positive men who have sex
with men (MSM) to almost 9 times the rate
of cervical cancer in women and to  37 times
that of HIV-negative MSM. In the HIV-infected
population, there is no clear evidence that
restoration of immunity with HAART allows high-grade
anal intraepithelial neoplasia (AIN) to regress or
resolve.
Because
HAART has allowed HIV-infected patients to live
for decades in relative immunosuppression (compared with
the general population), the incidence of AIN and
SCC in HIV-positive persons who are coinfected
with HPV is expected to increase.
Current
estimates predict that 5% of HIV-positive men
with high-grade AIN may have progression to SCC.
Cytological screening for AIN and SCC using anal
Papanicolaou (Pap) smear testing in HIV-infected men
is cost-effective, although the predictive value
of a screening anal Pap smear to detect histologically
proven high-grade dysplasia may be low.
In
the current study, investigators compared the pathological
diagnoses obtained by anal Papanicolaou (Pap) smear
with those obtained by anal biopsy or by surgical
excision for 153 men who have sex with men
(MSM).
Analysis
of these paired specimens showed that anal
Pap smears were an inaccurate predictor of
high-grade anal dysplasia, regardless of human immunodeficiency
virus (HIV) serostatus. The presence of any abnormal
anal cytological finding indicates a potential
for high-grade dysplasia on histological examination
of MSM.
Discussion
Given the increased
incidence of invasive SCC of the anal canal
among MSM, eradication of high-grade AIN
is under evaluation as a method for prevention
of anal cancer, analogous to the management of
high-grade cervical dysplasia in women. The data
presented in this study regarding the correlation
between anal cytological findings and histological findings
are strikingly similar to cervical cytological
and histological findings.
As
such, these data indicate that MSM with screening anal
Pap smears that are not normal should be considered
for HRA and submission of tissue for pathological
examination if indicated. The impact of ablating
histologically confirmed high-grade AIN on the
incidence of anal SCC is currently under investigation.
The
authors conclude, “This study independently confirms
that a substantial proportion of low-grade dysplasia
on anal Pap smears occurs with high-grade AIN
in MSM. Although randomized trials are lacking,
ablation of high-grade AIN has been suggested
as an intervention for cancer prevention.”
“
This study confirms that abnormal anal cytological
findings of any grade should suggest the possibility
of high-grade histological findings. These findings
could have an impact on the use of HRA as
a screening tool for high-grade AIN.”
Beth
Israel Deaconess Medical Center,
Harvard Medical School, and
PerkinElmer Life Sciences, Boston,
Massachusetts.
05/07/04
Reference
L A Panther
and others. High Resolution Anoscopy
Findings for Men Who
Have Sex with Men: Inaccuracy
of Anal Cytology as
a Predictor of Histologic
High-Grade Anal Intraepithelial
Neoplasia and the Impact
of HIV Serostatus.
Clinical Infectious Diseases 38:1495-1497. May 15, 2004.
|
