Screening for Anal Cancer in Women.

OBJECTIVE: The incidence of anal cancer is higher in women than men in the general population and has been increasing for several decades. Similar to cervical cancer, most anal cancers are associated with human papillomavirus (HPV), and it is believed that anal cancers are preceded by anal high-grade squamous intraepithelial lesions (HSIL). Our goals were to summarize the literature on anal cancer, HSIL, and HPV infection in women and to provide screening recommendations in women. METHODS: A group of experts convened by the American Society for Colposcopy and Cervical Pathology and the International Anal Neoplasia Society reviewed the literature on anal HPV infection, anal SIL, and anal cancer in women. RESULTS: Anal HPV infection is common in women but is relatively transient in most. The risk of anal HSIL and cancer varies considerably by risk group, with human immunodeficiency virus-infected women and those with a history of lower genital tract neoplasia at highest risk compared with the general population. CONCLUSIONS: While there are no data yet to demonstrate that identification and treatment of anal HSIL leads to reduced risk of anal cancer, women in groups at the highest risk should be queried for anal cancer symptoms and required to have digital anorectal examinations to detect anal cancers. Human immunodeficiency virus-infected women and women with lower genital tract neoplasia may be considered for screening with anal cytology with triage to treatment if HSIL is diagnosed. Healthy women with no known risk factors or anal cancer symptoms do not need to be routinely screened for anal cancer or anal HSIL.

Progression of anal high-grade squamous intraepithelial lesions to invasive anal cancer among HIV-infected men who have sex with men.

The incidence of anal cancer is elevated in human immunodeficiency virus (HIV)-infected men-who-have-sex-with-men (MSM) compared to the general population. Anal high-grade squamous intraepithelial lesions (HSIL) are common in HIV-infected MSM and the presumed precursors to anal squamous cell cancer; however, direct progression of HSIL to anal cancer has not been previously demonstrated. The medical records were reviewed of 138 HIV-infected MSM followed up at the University of California, San Francisco, who developed anal canal or perianal squamous cancer between 1997 and 2011. Men were followed up regularly with digital anorectal examination (DARE), high-resolution anoscopy (HRA) and HRA-guided biopsy. Although treatment for HSIL and follow-up were recommended, not all were treated and some were lost to follow-up. Prevalent cancer was found in 66 men. Seventy-two HIV-infected MSM developed anal cancer while under observation. In 27 men, anal cancer developed at a previously biopsied site of HSIL. An additional 45 men were not analyzed in this analysis due to inadequate documentation of HSIL in relation to cancer location. Of the 27 men with documented progression to cancer at the site of biopsy-proven HSIL, 20 men progressed from prevalent HSIL identified when first examined and seven men from incident HSIL. Prevalent HSIL progressed to cancer over an average of 57 months compared to 64 months for incident HSIL. Most men were asymptomatic, and cancers were detected by DARE. Anal HSIL has clear potential to progress to anal cancer in HIV-infected MSM. Early diagnosis is facilitated by careful follow-up. Carefully controlled studies evaluating efficacy of screening for and treatment of HSIL to prevent anal cancer are needed.

Predictors of postoperative urinary retention after colorectal surgery.

BACKGROUND: National quality initiatives have mandated the earlier removal of urinary catheters after surgery to decrease urinary tract infection rates. A potential unintended consequence is an increased postoperative urinary retention rate. OBJECTIVE: The aim of this study was to determine the incidence and risk factors for postoperative urinary retention after colorectal surgery. DESIGN: This was a prospective observational study. SETTINGS: A colorectal unit within a single institution was the setting for this study. PATIENTS: Adults undergoing elective colorectal operations were included. INTERVENTIONS: Urinary catheters were removed on postoperative day 1 for patients undergoing abdominal operations, and on day 3 for patients undergoing pelvic operations. Postvoid residual and retention volumes were measured. MAIN OUTCOME MEASURES: The primary outcomes measured were urinary retention and urinary tract infection. RESULTS: The overall urinary retention rate was 22.4% (22.8% in the abdominal group, 21.9% in the pelvic group) and was associated with longer operative time and increased perioperative fluid administration. Mean operative time for those with retention was 2.8 hours and, for those without retention, the mean operative time 2.2 hours (abdominal group 2 hours vs 1.4 hours, pelvic group 3.9 hours vs 3.1 hours, p ≤ 0.02). Patients with retention received a mean of 2.7L during the operation, whereas patients without retention received 1.8L (abdominal group 1.9L vs 1.4L, pelvic group 3.6L vs 2.2L, p < 0.01). In the abdominal group, patients with and without retention also received different fluid volumes on postoperative days 1 (2.2L vs 1.7L, p = 0.004) and 2 (1.6L vs 1L, p = 0.05). Laparoscopic abdominal group had a 40% retention rate in comparison with 12% in the open abdominal group (p = 0.004). Age, sex, preoperative radiation therapy, preoperative prostatism, preoperative diagnosis, and level of anastomosis were not associated with retention. The urinary tract infection rate was 4.9%. LIMITATION: The lack of documentation of preoperative urinary function was a limitation of this study. CONCLUSIONS: The practice of earlier urinary catheter removal must be balanced with operative time and fluid volume to avoid high urinary retention rates. Also important is increased vigilance for the early detection of retention.

Orthovoltage intraoperative radiotherapy for locally advanced and recurrent colorectal cancer.

BACKGROUND: Locally advanced and recurrent colorectal cancers pose a significant therapeutic challenge. Orthovoltage intraoperative radiotherapy provides one potential means of improving disease control at the time of surgery. OBJECTIVE: This study sought to analyze outcomes and identify prognostic factors of patients treated with orthovoltage intraoperative radiotherapy for locally advanced or recurrent colorectal cancer. DESIGN AND SETTING: This study is a retrospective chart review conducted at a tertiary medical center. PATIENTS: Between January 1990 and July 2009, 55 patients underwent intraoperative radiotherapy to a total of 61 sites for locally advanced (n = 14) or recurrent (n = 41) cancers of colon (n = 18) or rectum/rectosigmoid junction (n = 37). INTERVENTIONS: Median dose was 12 Gy (range, 7.5-20 Gy). Among locally advanced rectal/rectosigmoid cases, surgery included abdominoperineal resection (n = 3) or low anterior resection (n = 9). Seven treated sites had gross residual (R2) disease, 28 had pathologic or clinical microscopic residual disease (R1), and 15 were complete resections (R0). Treated sites included sacrum (n = 22), anterior pelvis/pelvic sidewall (19), sacrum and sidewall (n = 1), aortic bifurcation (n = 2), vaginal cuff (n = 2), psoas (n = 3), perivesicular region (n = 2), and other (n = 10). MAIN OUTCOMES MEASURES: Outcomes measures included in-field local control, locoregional control, overall survival, and grade ≥3 toxicity. RESULTS: At a median follow-up of 27 months (range, 4-237) among living patients, 2-year Kaplan-Meier estimates of in-field local control, locoregional control, and overall survival were 69%, 51%, and 59%. Margin status predicted for improved locoregional control (p = 0.01) and overall survival (p = 0.01). Seventeen patients (31%) developed a grade 3 to 5 toxicity following surgery with intraoperative radiotherapy. LIMITATIONS: This study was limited by its retrospective nature and relatively small sample size. CONCLUSIONS: Local control with intraoperative radiotherapy for locally advanced and recurrent colorectal cancers is good despite the high risk of residual disease. Among carefully selected patients, multimodality regimens including intraoperative radiotherapy may permit long-term survival.

Intensity-modulated radiation therapy versus conventional radiation therapy for squamous cell carcinoma of the anal canal.

BACKGROUND: The purpose of this study was to compare outcomes in patients with anal canal squamous cell carcinoma (SCCA) who were treated with definitive chemoradiotherapy by either intensity-modulated radiation therapy (IMRT) or conventional radiotherapy (CRT). METHODS: Forty-six patients who received definitive chemoradiotherapy from January 1993 to August 2009 were included. Forty-five patients received 5-fluorouracil with mitomycin C (n = 39) or cisplatin (n = 6). Seventeen (37%) were treated with CRT and 29 (63%) with IMRT. The median dose was 54 Gy in both groups. Median follow-up was 26 months (CRT) and 32 months (IMRT). T3-T4 stage (P = .18) and lymph node-positive disease (P = .6) were similar between groups. RESULTS: The CRT group required longer treatment duration (57 days vs 40 days, P < .0001), more treatment breaks (88% vs 34.5%, P = .001), and longer breaks (12 days vs 1.5 days, P < .0001) than patients treated with IMRT. Eleven (65%) patients in the CRT group experienced grade >2 nonhematologic toxicity compared with 6 (21%) patients in the IMRT group (P = .003). The 3-year overall survival (OS), locoregional control (LRC), and progression-free survival were 87.8%, 91.9%, and 84.2%, respectively, for the IMRT groups and 51.8%, 56.7%, and 56.7%, respectively, for the CRT group (all P < .01). On multivariate analysis, T stage, use of IMRT, and treatment duration were associated with OS, and T stage and use of IMRT were associated with LRC. CONCLUSIONS: The use of IMRT was associated with less toxicity, reduced need for treatment breaks, and excellent LRC and OS compared with CRT in patients with SCCA of the anal canal.

Diagnostic problems in anal pathology.

Anal squamous cell carcinoma and its precursor lesions are increasing in incidence in the United States and Europe. This trend predates human immunodeficiency virus/acquired immune deficiency syndrome and has been associated with persistent high-risk human papilloma virus (HPV) genotype infection, previous lower genital tract dysplasia/carcinoma, high frequency anoreceptive intercourse, heavy cigarette smoking, immunosuppression in solid organ transplant and immune disorders, and human immunodeficiency virus seropositivity. Screening protocols for at-risk patients are under active investigation and pathologists are often asked to assess anal canal and perianal biopsies for the presence of dysplasia and/or invasive carcinoma. Because underdiagnosis and overdiagnosis of anal cancer and precancer may lead to inappropriate treatment, it is important for the pathologist to be aware of current screening strategies, specific risk lesions, and the role of pathology in initial diagnosis and evaluation of anal biopsy and/or resection specimens. Standardized histologic criteria and uniform terminology should be used for reporting all anal canal and perianal squamous intraepithelial lesions. HPV subtyping, anal cytology, and recently identified biomarkers, such as p16 and Becton Dickinson ProEx C may provide additional information in problematic cases, but it is important to be aware of the limitations of these assays. HPV has been linked to all the major histologic subtypes of anal carcinoma (eg, basaloid, cloacogenic, transitional, etc.) and this association is strongest for anal canal lesions. With the possible exception of the microcystic pattern, histologic subtype does not seem to predict prognosis; and anal squamous cell carcinomas should be classified as either keratinizing or nonkeratinizing. Poorly differentiated squamous cell carcinomas have a worse prognosis and should be distinguished from poorly differentiated adenocarcinoma, melanoma, and neuroendocrine tumors. Very well differentiated squamous cell carcinoma with pushing margins (so-called giant condyloma of Buschke and Lowenstein) should be classified as verrucous carcinoma; this tumor shows aggressive local infiltration but does not metastasize. As all anal condylomata may harbor foci of high-grade dysplasia or invasive carcinoma, careful sectioning and complete histologic examination is required.

High-resolution anoscopy targeted surgical destruction of anal high-grade squamous intraepithelial lesions: a ten-year experience.

PURPOSE: This study was designed to determine whether high-resolution anoscopy and targeted surgical destruction of anal high-grade squamous intraepithelial lesions is effective in controlling high-grade squamous intraepithelial lesions while preserving normal tissues. METHODS: Retrospective review of 246 patients with high-grade squamous intraepithelial lesions treated with high-resolution anoscopy-targeted surgical destruction from 1996 to 2006, with at least one follow-up at a minimum two months with physical examination, high-resolution anoscopy, cytology, and biopsy when indicated. RESULTS: Lesions were extensive in 197 patients (81 percent); 207 (84 percent) were men, and 194 (79 percent) were immunocompromised (HIV or other). Persistent disease occurred in 46 patients (18.7 percent), requiring planned staged therapy; 10 required surgery. Recurrent high-grade squamous intraepithelial lesions occurred in 114 patients (57 percent) at an average 19 (range, 3-92) months; 26 of these required surgery. All other patients were retreated in-office with high-resolution anoscopy-directed therapies. Complications were seen in nine patients (4 percent). Despite treatment, three patients progressed to invasive cancer (1.2 percent). At their last visit, 192 patients (78 percent) had no evidence of high-grade squamous intraepithelial lesions. CONCLUSIONS: High-resolution anoscopy-targeted destruction combined with office-based surveillance and therapy is effective in controlling high-grade squamous intraepithelial lesions and is superior to reports of expectant management or traditional mapping procedures.

The Efficacy of a Novel Surgical Device in Preventing Intraoperative Wound Contamination in an In Vivo Porcine Model.

BACKGROUND: Surgical site infections (SSIs) remain a morbid and costly complication in abdominal surgery. Topical antibiotic delivery via intraoperative irrigation and barrier wound protection are strategies for preventing SSI. We tested the safety and efficacy of a novel wound protector device with an integrated fluid irrigation platform in a porcine model. METHODS: A simulated colorectal resection model was designed and performed on adult female pigs with a standardized concentration of 109 colony-forming units (CFU) of Escherichia coli administered to the wound site in 10 mL of normal saline (n = 7). The device was tested intraoperatively with and without irrigation with gentamicin-containing irrigant solution. Swab and tissue samples were obtained in addition to peripheral blood samples. Quantitative culture analysis was performed in addition to histological and immunohistochemical analysis and gentamicin concentration measurements. RESULTS: There were no adverse events observed in the animals. Tissue protected by the device yielded exponentially lower levels of E. coli growth compared to exposed tissue, with a mean 1 × 102 CFU/swab. Use of the device, both with and without irrigation, was associated with an exponential reduction in quantitative bacterial load compared to the control wounds with no device, with limited growth after wound closure in the pigs receiving irrigation. Histology and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining analysis revealed no significant damage to tissue. Serum gentamicin levels remained below the clinical threshold and decreased over time. CONCLUSIONS: This in vivo study suggests safety and efficacy of a novel device for the prevention of intraoperative wound contamination.

Role of human papillomavirus in squamous cell metaplasia-dysplasia-carcinoma of the rectum.

Primary colorectal squamous cell carcinoma (SCC) and squamous dysplasia are uncommon and little is known about their pathogenesis. Most have been reported in association with ulcerative colitis and other chronic disease states. Although cervical and anal SCC have been strongly linked to human papillomavirus (HPV) infection, the role of HPV in rectal squamous carcinoma has not been well-examined. We evaluated 3 cases of primary rectal SCC for the presence of high-risk HPV by immunohistochemistry for p16(INK4A), in situ hybridization, and polymerase chain reaction. HPV type 16 was detected by polymerase chain reaction in all cases. In addition, all cases exhibited diffuse strong reactivity for p16(INK4A) and punctate nuclear staining by Ventana HPVIII in situ hybridization. The presence of HPV 16 in all three cases suggests that high-risk HPV infection is a risk factor for rectal SCC, particularly in patients with underlying chronic inflammatory disease processes or altered immune status. Further studies are warranted to determine if SCC occurring more proximal in the colon are also HPV-dependent or occur via another, HPV-independent pathway.

High resolution anoscopy in the planned staged treatment of anal squamous intraepithelial lesions in HIV-negative patients.

Anal dysplasia (low-grade squamous intraepithelial lesions, LSIL; high-grade squamous intraepithelial lesions, HSIL) is a challenging disease for the surgeon. We reviewed 42 patients that underwent high-resolution anoscopy (HRA)-targeted surgical therapy of anal dysplasia in the past 10 years. Patients were followed up in the Anal Neoplasia Clinic with physical examination, cytology, HRA, and biopsy if indicated. Patients with disease amenable to local therapy were treated with office-based HRA-directed therapies. There were 30 men (mean age 39 years, range 21-63) and 12 women (mean age 50 years, range 31-71) included in the study. HSIL was present in 33, with four undergoing planned staged treatment due to circumferential disease. HSIL recurred in 45%, and most were re-treated successfully in-office. Progression to HSIL was seen in one patient with LSIL and to squamous cell carcinoma in one patient with HSIL despite therapy. No patients with LSIL had dysplasia at last follow-up. Minor complications occurred in three patients. HRA-targeted surgical therapy coupled with surveillance and re-treatment with office-based therapies offered an effective method in controlling anal dysplasia in the immunocompetent patient. Morbidity is minimal, and our progression to cancer rate is low (2.4%).

The Prognostic Significance of Pretreatment Hematologic Parameters in Patients Undergoing Resection for Colorectal Cancer.

OBJECTIVES: The prognostic value of several hematologic parameters, including platelet, lymphocyte, and neutrophil counts, has been studied in a variety of solid tumors. In this study, we examined the significance of inflammatory markers and their prognostic implications in patients with colorectal cancer (CRC). MATERIALS AND METHODS: Patients with stage I-III CRC who underwent surgical resection at the Stanford Cancer Institute between 2005 and 2009 were included. Patients were excluded if they did not have preoperative complete blood counts performed within 1 month of surgical resection, underwent preoperative chemotherapy or radiation, had metastatic disease at diagnosis, or had another previous malignancy. We included 129 eligible patients with available preoperative complete blood counts in the final analysis. RESULTS: A preoperative neutrophil-to-lymphocyte ratio of>3.3 was significantly associated with worse disease-free (DFS) and overall survival (OS) (P=0.009, 0.003), as was a preoperative lymphocyte-to-monocyte ratio of ≤2.6 (P=0.01, 0.002). Preoperative lymphopenia (P=0.002) was associated with worse OS but not DFS (P=0.09). In addition, preoperative thrombocytosis was associated with worse DFS (P=0.006) and OS (P=0.010). Preoperative leukocytosis was associated with worse OS (P=0.048) but not DFS (P=0.49). Preoperative hemoglobin was neither associated with OS (P=0.24) or DFS (P=0.15). CONCLUSIONS: Pretreatment lymphopenia, thrombocytosis, a decreased lymphocyte-to-monocyte ratio, and an elevated neutrophil-to-lymphocyte ratio independently predict for worse OS in patients with CRC.

p16 is superior to ProEx C in identifying high-grade squamous intraepithelial lesions (HSIL) of the anal canal.

Although the incidence of human papillomavirus (HPV)-associated anal neoplasia is increasing, interobserver and intraobserver reproducibility in the grading of biopsy specimens from this area remains unacceptably low. Attempts to produce a more reproducible grading scheme have led to the use of biomarkers for the detection of high-risk HPV (HR-HPV). We evaluated the performance of standard morphology and biomarkers p16, ProEx C, and Ki-67 in a set of 75 lesions [17 nondysplastic lesions, 23 low-grade squamous intraepithelial lesions (LSIL)/condyloma, 20 high-grade squamous intraepithelial lesions (HSIL), 15 invasive squamous cell carcinomas] from the anal and perianal region in 65 patients and correlated these findings with HPV subtype on the basis of a type-specific multiplex real-time polymerase chain reaction assay designed to detect HR-HPV. A subset of cases with amplifiable HPV DNA was also sequenced. HSIL was typically flat (15/20), and only a minority (4/20) had koilocytes. In contrast, only 1 LSIL was flat (1/23), and the remainder were exophytic. The majority of LSIL had areas of koilocytic change (20/23). HR-HPV DNA was detected in the majority (89%) of invasive carcinomas and HSIL biopsies, 86% and 97% of which were accurately labeled by strong and diffuse block-positive p16 and ProEx C, respectively. LSIL cases, however, only infrequently harbored HR-HPV (13%); most harbored low-risk HPV (LR-HPV) types 6 and 11. Within the LSIL group, p16 outperformed ProEx C, resulting in fewer false-positive cases (5% vs. 75%). Ki-67 was also increased in HR-HPV-positive lesions, although biopsies with increased inflammation and reactive changes also showed higher Ki-67 indices. These data suggest that strong and diffuse block-positive nuclear and cytoplasmic labeling with p16 is a highly specific biomarker for the presence of HR-HPV in anal biopsies and that this finding correlates with high-grade lesions.

Do hospitals that serve a high percentage of Medicaid patients perform well on evidence-based guidelines for colon cancer care?

BACKGROUND: Previous work suggests hospitals serving high percentages of patients with Medicaid are associated with worse colon cancer survival. It is unclear if practice patterns in these settings explain differential outcomes. HYPOTHESIS: High Medicaid hospitals (HMH) have lower compliance with evidence-based care processes (examining 12 or more lymph nodes (LN) during surgical staging and providing appropriate chemo-therapy). METHODS: Retrospective analysis of stage I-III colon cancers from California Cancer Registry (1996-2006) linked to discharge abstracts and hospital profiles predicted hospital compliance with guidelines and trends in compliance over time. RESULTS: Cases (N=60,000) in 439 hospitals analyzed. High Medicaid hospital settings had lower odds of compliance with the 12 LN exam (OR(HMH)0.91, CI(HMH)[0.85, 0.98]) and with the delivery of appropriate chemotherapy (OR(HMH)0.76, CI(HMH)[0.67, 0.86]). CONCLUSIONS: High Medicaid hospital status is associated with poor performance on evidence-based colon cancer care. Policies to improve the quality of colon cancer care should target these settings.

Management of anal squamous intraepithelial lesions.

Anal squamous intraepithelial lesions include both low-grade squamous intraepithelial lesions (LSIL) and high-grade squamous intraepithelial lesions (HSIL) and are caused by chronic infection with the human papillomavirus (HPV). The disease is increasing in both incidence and prevalence, especially among patients with the following risk factors: homosexual men, acquired or iatrogenic immunosuppression, and presence of other HPV-related diseases. Although the natural history of the disease is unknown, there is significant evidence that untreated HSIL progresses to squamous cell carcinoma in 11% of patients and in up to 50% of patients with extensive disease and immunosuppression. Anal cytology and reflex HPV DNA testing are used to screen for disease, particularly among patients with the aforementioned risk factors. Evaluation of the patient should include physical examination and high-resolution anoscopy (HRA) to evaluate for disease above and below the dentate line. Intervention is warranted and this can be achieved in many ways. The treatment option associated with the best outcomes is ablation directed with HRA, which can be performed in the office or in the operating room with minimal morbidity. This strategy is effective in patients with both low-volume and high-volume disease and is associated with a malignant progression rate of 0.4% in patients with treated HSIL.

Mechanical bowel preparation in intestinal surgery: a meta-analysis and review of the literature.

INTRODUCTION: Despite several meta-analyses and randomized controlled trials showing no benefit to patients, mechanical bowel preparation (MBP) remains the standard of practice for patients undergoing elective colorectal surgery. METHODS: We performed a systematic review of the literature of trials that prospectively compared MBP with no MBP for patients undergoing elective colorectal resection. We searched MEDLINE, LILACS, and SCISEARCH, abstracts of pertinent scientific meetings and reference lists for each article found. Experts in the field were queried as to knowledge of additional reports. Outcomes abstracted were anastomotic leaks and wound infections. Meta-analysis was performed using Peto Odds ratio. RESULTS: Of 4,601 patients (13 trials), 2,304 received MBP (Group 1) and 2,297 did not (Group 2). Anastomotic leaks occurred in 97(4.2%) patients in Group 1 and in 81(3.5%) patients in Group 2 (Peto OR = 1.214, CI 95%:0.899-1.64, P = 0.206). Wound infections occurred in 227(9.9%) patients in Group 1 and in 201(8.8%) patients in Group 2 (Peto OR = 1.156, CI 95%:0.946-1.413, P = 0.155). DISCUSSION: This meta-analysis demonstrates that MBP provides no benefit to patients undergoing elective colorectal surgery, thus, supporting elimination of routine MBP in elective colorectal surgery. CONCLUSION: In conclusion, MBP is of no benefit to patients undergoing elective colorectal resection and need not be recommended to meet "standard of care."

Transperineal repair of persistent rectovaginal fistulas using an acellular cadaveric dermal graft (AlloDerm).

A number of surgical techniques have been described to treat rectovaginal fistulas. Recurrent or persistent fistulas after previous repair can be particularly difficult to treat. We report a novel technique used to successfully repair rectovaginal fistulas after failed mucosal advancement flap procedures using a transperineal-layered closure with an interposed graft of acellular cadaveric dermis (Alloderm).

High resolution anoscopy and targeted treatment of high-grade squamous intraepithelial lesions.

PURPOSE: The purpose of this video is to illustrate the use of high resolution anoscopy in the diagnosis and treatment of anal high-grade squamous intraepithelial lesions. METHODS: Five patients with anal dysplasia were examined in the operating room with acetic acid and the operative microscope. Lugol's solution was used selectively. Acetic acid is generously applied to aide in the recognition of high-grade squamous intraepithelial lesions. Acetowhite regions are examined under the operative microscope to further distinguish lesions as either low-grade squamous intraepithelial lesions or high-grade squamous intraepithelial lesions. Acetowhite lesions with specific vascular characteristics like punctuate vessels or honeycomb patterns are highly suggestive of high-grade disease. These lesions are selectively destroyed under direct visualization with an effort to maintain normal mucosa and skin to prevent stenosis. Some pigmented lesions contain high-grade squamous intraepithelial lesions; the operative microscope is used in this setting to look for the vascular characteristics of high-grade disease. RESULTS: The video reports five male patients treated for high-grade squamous intraepithelial lesions with the aide of high resolution anoscopy. There were no intraoperative or postoperative complications. All lesions suspicious for high-grade squamous intraepithelial lesions based on observed vascular patterns were confirmed as such with permanent histopathology. CONCLUSION: The use of acetic acid and the operative microscope with selective use of Lugol's solution accentuates the visual characteristics of high-grade lesions, enhancing the surgeon's ability to target treatment to high-grade squamous intraepithelial lesions. High resolution anoscopy is useful in the targeted treatment of high-grade squamous intraepithelial lesions.