High-resolution anoscopy (HRA) is analogous to cervical colposcopy. During HRA, a lubricated anoscope is inserted into the anal canal. A cotton swab wrapped in gauze and soaked in 3-percent acetic acid is then inserted through the anoscope, and the anoscope is removed, leaving the gauze in place. The acetic acid gives dysplastic epithelium a white appearance. After 2 minutes, the gauze is removed and the anoscope reinserted. A high-resolution colposcope (magnification of 10x to 40x) is used to view the walls of the anus. A biopsy of suspicious tissue can be taken.
Anal squamous dysplasia describes a spectrum of diseases that ranges from low-grade squamous intraepithelial lesions (LSIL) to higher grade squamous lesions, or to invasive anal squamous cell carcinoma (SCC). Recent reports have shown a significant increase in squamous lesions in immunocompromised individuals and men who have sex with men (MSM). These lesions are associated with chronic infection with the human papillomavirus (HPV).
CPT® codes 46601 and 46607 should be used only in these circumstances: patients with abnormalities on anoscopy, abnormalities in digital rectal examination, history of HPV-related anal disease or abnormalities in anorectal cytology.
Current evidence does not support coverage for routine screening in any population at this time. The clinical chart must have documentation of the abnormalities described above.