1500. Collection Device Comparison for Anal Cancer Screening in HIV-infected Individuals
Session: Poster Abstract Session: HIV and Co-infections
Saturday, October 5, 2013
Room: The Moscone Center: Poster Hall C
Background: Due to the increasing incidence of anal cancer in HIV, public health advocates have recommended screening for anal cancer with anal cytology (APAP).  However, there is limited information regarding the optimal screening device for APAP.  A moistened Dacron swab (DS) has historically been used, though its performance is limited. Extrapolating from cervical Pap devices, a cytobrush (CB) may improve the identification of anal intraepithelial neoplasia and cancer. This prospective study evaluates the performance of a moistened DS and a CB in the same patient.

Methods: We recruited 57 HIV-infected and 3 organ transplanted subjects with an abnormal APAP who presented for high resolution anoscopy with biopsy (n=56).  After a standard-of-care (SOC) APAP using a DS, each subject underwent a second sampling: 30 subjects with a DS and 30 with a CB.  Study pathologists then assigned each sample a cellularity score, diagnosis (Bethesda system), and noted the presence or absence of transformation zone components (TZC) as an indicator of specimen adequacy.  Anal biopsies were taken as per SOC and categorized as negative, AIN I/warts, or AINII-III.  We recorded clinical characteristics, including those affecting cytology yield.

Results: DS and CB had fair agreement of the cellularity index (K=0.3) and TZC (K=0.3).  A CB detected a significantly higher number of TZC than the DS (67% vs. 45%, McNemar’s test p=.007).  The agreement of APAP results between the two devices was moderate, K=0.58.  Histology results are in Table 1.  Of eight HSIL APAPs, six were AINII-III and two were negative on biopsy.  There is little difference in predictive yield of AIN II-III between DS and CB.    

Table 1

APAP

Histology (n=56)

DS

Normal (%)

AINI/warts (%)

AINII-III (%)

LSIL (31)

3 (5.3)

9 (16.1)

19 (33.9)

HSIL (6)

2 (3.6)

0 (0)

4 (7.1)

CB

 

LSIL (34)

4 (7.1)

9 (16.1)

19 (33.9)

HSIL (2)

0 (0)

0 (0)

2 (3.6)

Total

12(21.4)

18(32.1)

26(46.4)

Conclusion: Our results show that a CB is comparable to a DS with regards to cytology yield.  APAP using CB yields less cellularity, but improved sample quality when compared to a DB.  Pap results of both devices poorly predict accurate histology, as previously reported.   Performance of HPV DNA and other molecular markers are currently underway and might provide further guidance as to the optimal sampling device for anal cancer screening.

Doreen Lee, MD1, Rebecca Levine, MD1, Samer Khader, MD1, Mark Suhrland, MD1, Mimi Kim, ScD2, David Smotkin, MD, PhD1, Robert Burk, MD2, Robert Grossberg, MD1 and Mark Einstein, MD, MS2, (1)Montefiore Medical Center, Bronx, NY, (2)Albert Einstein College of Medicine, Bronx, NY

Disclosures:

D. Lee, None

R. Levine, None

S. Khader, None

M. Suhrland, None

M. Kim, None

D. Smotkin, None

R. Burk, None

R. Grossberg, None

M. Einstein, None

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