Anal canal The incidence of anal HPV related squamous cell carcinoma is on the rise, especially in HIV positive men who have sex with men (MSM). Women who are HIV positive and women

with cervical intraepithelial lesions (CIN) have an increased risk of HPV infections of the anal canal and anal intraepithelial lesions (AIN). Like cervical cancer, anal cancer is also associated with precursor lesions (AIN) detectable on exfoliative cytology. Anal-rectal cytology screening programs have been developed in an Inhibitors,research,lifescience,medical effort to detect and to eradicate precursor lesions prior to progression to invasive squamous cell carcinoma Inhibitors,research,lifescience,medical and are recommended for these population groups. Either conventional or liquid based anal-rectal cytology specimens are acceptable, but liquid based specimens are preferred, as apart from better morphologic details, residual liquid can be used for ancillary studies, such as testing for high-risk HPV DNA. Anal cytologic specimens may be collected by health care professionals or by patients using a gloved finger or by direct scraping/brushing (by means of an

endocervical brush, wooden spatula, moistened cotton or Dacron Inhibitors,research,lifescience,medical swabs). A minimum of 2,000-3,000 AMPK activators review nucleated squamous cells comprise adequate specimens. Some glandular/columnar cells

from the anal transition zone should ideally be present to indicate that the anorectal transition zone has been sampled (Figure 17). Many anal squamous dysplasias and carcinomas Inhibitors,research,lifescience,medical Inhibitors,research,lifescience,medical arise in this transition zone. Proper training and experience in obtaining these specimens yields satisfactory specimens. The evaluation of anal Pap slides is reported in a manner similar to that of gynecologic Pap test slides. Anal intraepithelial neoplasia (AIN) is divided into low and high grade by criteria similar to those used for cervical squamous dysplasias. Diagnostic terminology Metalloexopeptidase as defined by the Bethesda System for Reporting Cervical Cytology (TBS 2001) (40) should be used. Cytologic interpretations on anal specimens do not always correlate with severity of lesions identified on subsequent biopsy; thus, patients with atypical squamous cells of undetermined significance (ASC-US) or worse should be referred for anoscopy (41,42). Figure 17 A. normal anal Pap with intermediate and basal squamous cells and glandular cells (Pap stain, 400×); B. AIN1, showing a koilocyte with a prominent perinuclear cavity (Pap stain, 400×); C. AIN 3, displaying increased nuclear:cytoplasmic …