Detection of anal dysplasia is enhanced by narrow band imaging and acetic acid

Identification and Reporting of Anal Pathology during Routine Colonoscopies

The gold-standard procedure for anal canal examination is anoscopy. Nonetheless, patients are referred for a colonoscopy for many reasons, and a routine exam might provide an opportunity to diagnose anal pathologies, such as hemorrhoids, anal fissures, anal polyps, condylomas, and anal squamous cell carcinoma. It is important to know the main features of these conditions and relevant information to report in order to help guide patient treatment and follow-up.

Accuracy of narrow-band imaging in predicting the histology of anal intraepithelial lesions

BACKGROUND AND AIM

Anal intraepithelial neoplasia (AIN) is the precursor of anal squamous carcinoma, frequently underappreciated by most gastroenterologists. Purpose of the study is to assess the diagnostic accuracy of narrow-band imaging (NBI) in predicting the histology of anal lesions, considering a new NBI classification.

METHODS

This is a retrospective analysis of consecutive patients with suspected anal squamous intraepithelial lesions (SILs) and superficially invasive squamous cell carcinoma (SISCCA) who underwent anorectal-sigmoidoscopy. Three expert endoscopists reviewed all the images collected during colonoscopies in white light and NBI in order to generate a practical classification of three main different NBI patterns.

RESULTS

After the modified Delphi process, the final NBI classification, mainly based on intrapapillary capillary loops (IPCL) changes included three different NBI pattern. NBI pattern I: elongation of IPCL toward epithelial surface; NBI pattern 2: thickened and tortuous IPCL; NBI pattern 3: mosaic-like disposition of IPCL. We found that NBI pattern positively correlated to the histologic type of the lesions and tumor grade (Spearman's rho = 0.9671, P = 0.0000). Among 58 anal lesions included, 41/41 (100%) LSILs have been classified as NBI pattern I, 10/11 (90.91%) HSILs as NBI pattern II, 1/11 HSIL as NBI pattern I, 4/4 SISCCA as NBI pattern III and 2/2 invasive cancer as NBI pattern III. Diagnostic accuracy of NBI pattern II or III in predicting histology differentiating HSIL or SISCCA/IC versus LSIL showed a sensitivity of 100%, (95% CI: 92.3-100%) and a specificity of 94.1% (95% CI: 83.8-98.3%).

CONCLUSION

The accuracy of this new NBI score system in predicting the histology of anal lesions showed encouraging data in term of sensitivity and specificity in differentiating HSIL or SISCCA/IC versus LSIL, but the clinical usefulness and application of these findings should be evaluated in a prospective larger study.

Anal Squamous Intraepithelial Lesions and Anal Cancer Management in Low Resource Settings

A low resource setting (LRS) is defined as a health care system which does not meet the criteria defined by the World Health Organization (WHO) or other national/international organizations in the following areas: infrastructure, materials, and human resources. 1 Patients encounter barriers which limit their access to care and services that are considered standard of care. While LRS is most commonly associated with developing countries, it is easy to overlook communities in developed countries which lack the financial resources to afford basic health care. This article describes the societal implications and barriers to care for both squamous intraepithelial lesions (SILs) and anal cancer in LRS, the existing screening/surveillance approaches, available treatment approaches to anal cancer, and it also discusses potential evidence-based approaches to bridge the gap for these disparities in anal cancer care.

Anal cancer and precancerous lesions: a call for improvement

Anal squamous cell carcinoma is the most common type of anal cancer and is largely associated with anal human papillomavirus infection. The incidence of anal squamous cell carcinoma is increasing, and although still uncommon in the general population, a high incidence has been noted in specific population groups (eg, patients with HIV, men who have sex with men [MSM], recipients of solid organ transplants, women with genital neoplasia, and patients with systemic lupus erythematosus or inflammatory bowel disease). The higher incidence among individuals who are HIV-positive makes anal squamous cell carcinoma one of the most common non-AIDS-defining cancers among HIV-positive individuals. Anal cancer screening in high-risk groups aims to detect high-grade squamous intraepithelial lesions, which are considered anal precancerous lesions, and for which identification can provide an opportunity for prevention. A blind anal cytology is normally the first screening method, and for patients with abnormal results, this approach can be followed by an examination of the anal canal and perianal area under magnification, along with staining-a technique known as high-resolution anoscopy. Digital anorectal examination can enable early anal cancer detection. Several societies are in favour of screening for HIV-positive MSM and recipients of transplants. There are no current recommendations for screening of anal precancerous lesions via endoscopy, but in high-risk groups, a careful observation of the squamocolumnar junction should be attempted. Several treatments can be used to treat high-grade squamous intraepithelial lesions, including argon plasma coagulation or radiofrequency ablation, which are largely limited by high recurrence rates. Gastroenterologists need to be aware of anal squamous cell carcinoma and anal precancerous lesions, given that patients at high risk are frequently encountered in the gastroenterology department. We summarise simple procedures that can help in early anal squamous cell carcinoma detection.

Unsatisfactory exfoliative anal cytology samples, 15-year experience with histologic, cytologic, and molecular follow-up

BACKGROUND

The incidence of anal carcinoma has risen in recent decades. Exfoliative cytology screening of selected high risk patients is performed in many centers. Unsatisfactory cytology results are frustrating to patients, clinicians, and laboratorians. The aim of this study is to ascertain outcomes of patients with non-diagnostic anal cytology.

METHODS

A retrospective review of anal cytology testing performed at the Cleveland Clinic between 01/01/2001 and 12/31/2015 was performed. All cases were received as liquid-based samples and processed as ThinPreps (Hologic, Marlborough, MA). Co-testing for HR-HPV DNA was performed using Hybrid Capture 2® (Qiagen, Germantown, MD) in the majority of patients.

RESULTS

Of 1,276 ThinPrep anal cytology samples, 130 (10%) were deemed unsatisfactory. 77% of patients were HIV positive. 85% were males. Of the unsatisfactory cases, 116 (89%) were co-tested for HR-HPV DNA. Of those, 40 patients (34%) had a simultaneous positive HR-HPV DNA. Adequate follow up cytology within a one year and a two year period revealed that 18/130 (14%) and 26/130 (20%) of patients had ASC or SIL respectively. Histologic follow-up within one and two years showed 3 patients (2%) and 8 patients (6%) with HSIL or worse.

CONCLUSIONS

High risk patients with unsatisfactory anal cytology are not "negative". At least one-third proved to be concomitantly HR-HPV DNA positive with one-fifth showing subsequent cytologic squamous abnormalities and with more than 5% being diagnosed with a high grade intraepithelial lesion within two years. Prompt repeat cytology and/or HR-HPV DNA is recommended for high risk patients with non-diagnostic cytology.