Benign anal lesions, inflammatory bowel disease and risk for high-risk human papillomavirus-positive and -negative anal carcinoma

Perianal Fistulizing Crohn's Disease-Associated Anorectal and Fistula Cancers: Systematic Review and Expert Consensus

BACKGROUND & AIMS

Perianal fistulizing Crohn's disease (PFCD)-associated anorectal and fistula cancers are rare but often devastating diagnoses. However, given the low incidence and consequent lack of data and clinical trials in the field, there is little to no guidance on screening and management of these cancers. To inform clinical practice, we developed consensus guidelines on PFCD-associated anorectal and fistula cancers by multidisciplinary experts from the international TOpClass consortium.

METHODS

We conducted a systematic review by standard methodology, using the Newcastle-Ottawa Scale quality assessment tool. We subsequently developed consensus statements using a Delphi consensus approach.

RESULTS

Of 561 articles identified, 110 were eligible, and 76 articles were included. The overall quality of evidence was low. The TOpClass consortium reached consensus on 6 structured statements addressing screening, risk assessment, and management of PFCD-associated anorectal and fistula cancers. Patients with long-standing (>10 years) PFCD should be considered at small but increased risk of developing perianal cancer, including squamous cell carcinoma of the anus and anorectal carcinoma. Risk factors for squamous cell carcinoma of the anus, notably human papilloma virus, should be considered. New, refractory, or progressive perianal symptoms should prompt evaluation for fistula cancer. There was no consensus on timing or frequency of screening in patients with asymptomatic perianal fistula. Multiple modalities may be required for diagnosis, including an examination under anesthesia with biopsy. Multidisciplinary team efforts were deemed central to the management of fistula cancers.

CONCLUSIONS

Inflammatory bowel disease clinicians should be aware of the risk of PFCD-associated anorectal and fistula cancers in all patients with PFCD. The TOpClass consortium consensus statements outlined herein offer guidance in managing this challenging scenario.

Pathophysiology of Anal Cancer

The pathophysiology of the development of anal cancer is thought to be linked to chronic inflammation, a possible consequence of infections with human papillomavirus (HPV) or HIV, or inflammation from inflammatory bowel disease. Anal HPV-induced carcinogenesis bears similarities to its cervical counterpart via viral integration into the host genome and the development of precursor lesions termed anal intraepithelial neoplasia. HPV-16 and -18 are the most common HPV genotypes associated with anal cancer. Other risk factors for the development of anal cancer include chronic immunosuppression, sexual activity and sexually transmitted diseases, female gender, history of anogenital dysplasia, and smoking.

Executive Summary of the Lower Anogenital Tract Cancer Evidence Review Conference

The Centers for Disease Control and Prevention sponsored a project conducted by the American College of Obstetricians and Gynecologists to develop educational materials for clinicians on the prevention and early diagnosis of gynecologic cancers. For this final module, focusing on the cancers of the lower anogenital tract (vulva, vagina, and anus), a panel of experts in evidence assessment from the Society for Academic Specialists in General Obstetrics and Gynecology, ASCCP, and the Society of Gynecologic Oncology reviewed relevant literature and current guidelines. Panel members conducted structured literature reviews, which were then reviewed by other panel members. Representatives from stakeholder professional and patient advocacy organizations met virtually in September 2022 to review and provide comment. This article is the executive summary of the review. It covers prevention, early diagnosis, and special considerations of lower anogenital tract cancer. Knowledge gaps are summarized to provide guidance for future research.

Multidisciplinary management of anal intraepithelial neoplasia and rate of progression to cancer: A retrospective cohort study

PURPOSE

To describe the regional burden of AIN and rate of progression to cancer in patients managed in specialist and non-specialist clinic settings.

METHODS

Patients with a histopathological diagnosis of AIN between 1994 and 2018 were retrospectively identified. Clinicopathological characteristics including high-risk status (chronic immunosuppressant use or HIV positive), number and type of biopsy (punch/excision) and histopathological findings were recorded. The relationship between clinicopathological characteristics and progression to cancer was assessed using logistic regression.

RESULTS

Of 250 patients identified, 207 were eligible for inclusion: 144 from the specialist and 63 from the non-specialist clinic. Patients in the specialist clinic were younger (<40 years 31% vs 19%, p = 0.007), more likely to be male (34% vs 16%, p = 0.008) and HIV positive (15% vs 2%, p = 0.012). Patients in the non-specialist clinic were less likely to have AIN3 on initial pathology (68% vs 79%, p = 0.074) and were more often followed up for less than 36 months (46% vs 28%, p = 0.134). The rate of progression to cancer was 17% in the whole cohort (20% vs 10%, p = 0.061). On multivariate analysis, increasing age (OR 3.02, 95%CI 1.58-5.78, p < 0.001), high risk status (OR 3.53, 95% CI 1.43-8.74, p = 0.006) and increasing number of excisions (OR 4.88, 95%CI 2.15-11.07, p < 0.001) were related to progression to cancer.

CONCLUSION

The specialist clinic provides a structured approach to the follow up of high-risk status patients with AIN. Frequent monitoring with specialist assessments including high resolution anoscopy in a higher volume clinic are required due to the increased risk of progression to anal cancer.

Risk of Anal Cancer Following Benign Anal Disease and Anal Cancer Precursor Lesions: A Danish Nationwide Cohort Study

BACKGROUND

Human papillomavirus (HPV) is associated with the majority of anal high-grade intraepithelial neoplasia (AIN) and anal cancers. Little is known about the risk of anal cancer following a diagnosis of benign anal disease and AIN.

METHODS

Using data from nationwide, population-based Danish registries, a cohort of 126,174 individuals with either non-neoplastic anal disease or AIN 1 to 3 during 1970 to 2016 was followed until first occasion of anal cancer. Information on HIV status was obtained from the Danish HIV Cohort Study. The absolute risk of anal cancer was estimated using the Aalen-Johansen estimator taking into account censoring at emigration and end of follow-up and competing risk at time of death. Standardized incidence ratios (SIR) for anal cancer among individuals with non-neoplastic anal disease, including inflammatory lesions, hemorrhoids, and polyps, were estimated in Poisson models. Sex-, age-, and calendar period-specific national population rates were estimated using the Danish National Pathology Registry.

RESULTS

Anal cancer risk increased with increasing severity of lesions, reaching 4% 5 years after diagnosis of AIN3. Even among those with non-neoplastic anal lesions, particularly inflammatory lesions, anal cancer risk was significantly higher than expected from Danish national anal cancer rates (SIR = 2.8; 95% confidence intervals, 2.3-3.2). The absolute 5-year risk of anal cancer following AIN3 was considerably higher among HIV-positive (14.1%) than HIV-negative (3.2%) individuals.

CONCLUSIONS

Anal cancer risk increases with increasing severity of lesions and is especially high among HIV-positive individuals.

IMPACT

Vaccination against HPV is important in the prevention of both high-grade AIN and anal cancer.

The association between body mass index and anal canal human papillomavirus prevalence and persistence: the HIM study

Background: While receptive anal sex is an established risk factor for anal human papillomavirus (HPV) infection and squamous cell carcinoma of the anus (SCCA), people with anal HPV infection and SCCA commonly report no lifetime receptive anal sex suggesting other factors may also increase risk for anal HPV infection and persistence. Given potential associations between obesity and conditions that may cause perianal or anal canal lesions, we hypothesized that body mass index (BMI) was associated with HPV infection. Methods: Genotyping for 36 HPV types was conducted on anal canal specimens from men, ages 18-70, from Brazil, Mexico, and the USA. Eligibility included no history of genital warts or HIV. Evaluable specimens were collected from 328 men having sex with men (MSM) and 1348 men having sex with women (MSW) who reported no lifetime receptive anal sex. Prevalence of anal HPV infection and six-month persistence by BMI were estimated in addition to adjusted prevalence ratios for the association between BMI and HPV infection. Results: Among MSW, obese men had a higher prevalence of HPV-16 in the anal canal (3.1%), compared to normal weight men (1.3%) although 95% CI overlapped. Among MSM, prevalence of HPV decreased with increasing BMI. A similar pattern was observed for persistence. After adjustment for confounders, obese MSW had 2.4 times higher odds of HPV-16 compared to normal weight men. Conclusions: BMI may be positively associated with anal HPV (especially HPV-16) among MSW and negatively associated with anal HPV among MSM which supports continued universal HPV vaccination programs.

Medical and surgical management of perianal Crohn's disease

Crohn's disease is increasingly thought to encompass multiple possible phenotypes. Perianal manifestations account for one such phenotype and represent an independent disease modifier. In its more severe form, perianal Crohn's disease confers a higher risk of a severe and disabling disease course, relapses, hospital admissions and operations. This, in turn, imposes a considerable burden and disability on patients. Identification of the precise manifestation is important, as management is nuanced, with both medical and surgical components, and is best undertaken in a multidisciplinary setting for both diagnosis and ongoing treatment. The introduction of biologic medication has heralded a significant addition to the management of fistulizing perianal Crohn's disease in particular, albeit with modest results. It remains a very challenging condition to treat and further work is required to optimize management in this group of patients.

Syndemic synergy of HPV and other sexually transmitted pathogens in the development of high-grade anal squamous intraepithelial lesions

Background

Anal intraepithelial neoplasia is associated with high-risk human papillomavirus (hrHPV) as a precursor to anal cancer. However, factors other than hrHPV are likely to be involved and further study of cofactors is required because of the possibility of syndemic interactions.

Methods

Three hundred and fourteen patients underwent 457 operations. Histopathology and hrHPV testing using the Digene Hybrid Capture 2 (HC 2) method were performed. Demographic factors and sexually transmissible infections (STIs) were recorded.

Results

Results showed that hrHPV alone was associated with HSIL (OR = 4.65, p < 0.001). None of the other STIs were alone associated with HSIL but amplification of risk was found when hrHPV infection occurred with HIV (OR = 11.1); syphilis (OR = 5.58); HSV 2 (OR = 7.85); gonorrhoea (OR = 6.45) and some other infections.

Conclusions

These results suggest that hrHPV is a sufficient cause of anal HSIL. Seropositivity for HIV, HSV 2, T. pallidum, HBV and HCV and a history of gonorrhoea or chlamydia exert a powerful amplifying factor increasing the risk of HSIL above the risk with hrHPV alone. Other co-factors which are associated with an increased risk of HSIL are increased age, male gender, MSM behaviour and self-reported history of more than 50 sexual partners. This pattern of disease in patients with warts is characteristic of a syndemic with potential serious increased risk of anal carcinoma.

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High-risk HPV is a necessary and sufficient cause of progression from LSIL to HSIL.

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HIV, HSV 2, HBV and HCV are associated with an amplified risk of hrHPV induced HSIL.

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Gonorrhoea, chlamydia, and syphilis are associated with increased odds HSIL.

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HSIL shows syndemic interaction patterns with STIs and behavioural/social factors.

Anal Neoplasia in Inflammatory Bowel Disease: Classification Proposal, Epidemiology, Carcinogenesis, and Risk Management Perspectives

Patients with inflammatory bowel disease [IBD] may develop, similarly to individuals from general population, rare cases of human papilloma virus [HPV]-related anal canal squamous cell carcinoma [SCC] and intra-epithelial precursor lesions, as well as very rare cases of anal canal adenocarcinoma. Patients with chronic perianal Crohn's disease [CD] are at substantial risk of developing SCC or adenocarcinoma from the fistula-lining epithelium, as well as SCC or adenocarcinoma arising from chronic anorectal ulcerations or strictures. Based on this lesion stratification, we provide in this review tailored incidence estimates and we propose an IBD-specific classification of all types of anal neoplasia that may occur in patients with IBD. After reviewing putative carcinogenesis of all types of neoplasia, we conclude that HPV vaccination could reduce the incidence of HPV-related lesions, although an anal screening programme related to these lesions is not mandatory on the sole basis of IBD. By contrast, we point out that all patients with chronic perianal CD should be explored in depth, including biopsies under anaesthesia and fistula curettage when necessary, in case of any change in anal symptoms ─in particular new, increasing, unexplained pain. Finally, we conclude that there is an urgent need for elaborating and evaluating surveillance algorithms in patients with chronic perianal CD, in order to avoid cancers with late diagnosis and poor prognosis.

Review: Anal Intraepithelial Neoplasia in HIV-Infected Men Who Have Sex with Men: Is Screening and Treatment Justified?

Anal squamous cell carcinoma (SCC) is the fourth most prevalent cancer in human immunodeficiency virus (HIV)-infected men who have sex with men (MSM). Human papillomavirus (HPV) has been detected in over 90% of anal carcinoma biopsy specimens from MSM, and is considered a necessary, but alone, insufficient factor for carcinogenesis. Anal intraepithelial neoplasia (AIN) may be precursive for SCC, and screening cytology with referral of persons with abnormality for high-resolution anoscopy-guided biopsy, and AIN treatment, has been recommended for prevention. In the absence of either randomized controlled trials or surveillance data demonstrating a reduction in anal SCC incidence, these recommendations were based on analogy with cervical cancer. HPV-mediated genetic changes associated with cervical cancer, and aneuploidy, have been documented in AIN. However, little data exist on the rate of AIN progression to SCC. The treatment of AIN is frequently prolonged and not curative, and if routinized in the care of HIV-infected MSM, would likely be recurring well into their sixth decade of life. Clinical trials demonstrating a reduction in invasive anal carcinoma incidence, as well as acceptable morbidity with repeated AIN destruction, are needed before asking our patients to commit to routine treatment.

Anal Neoplasia in Inflammatory Bowel Disease Is Associated With HPV and Perianal Disease

OBJECTIVES:

Literature describing the risk factors predisposing inflammatory bowel disease (IBD) patients to anal squamous neoplasia is very scarce. Case reports and small case series have implicated perianal Crohn's disease (CD), long-standing IBD, human papillomavirus (HPV) infection, and immunosuppressive treatment. In this study, we retrospectively examined the association between HPV infection and anal squamous neoplastic lesions among IBD patients from our center.

METHODS:

We reviewed the pathology records and slides of IBD patients diagnosed with anal squamous cell carcinomas (SCCs), high-grade squamous intraepithelial lesions (HSILs), and low-grade squamous intraepithelial lesions (LSILs) who presented at our center between 1 March 1994 and 9 September 2014. The HPV status of the neoplasms was assessed histologically, by immunohistochemical staining for p16 overexpression, and by global and type-specific HPV PCR.

RESULTS:

SCCs, HSILs, LSILs, and small cell carcinoma were identified, respectively, in six, nine, two, and one IBD patients. All six patients with SCC had CD with perianal involvement. HPV-related neoplasia was identified in 3/6 cases of SCC (all HPV-16), 1/1 small cell carcinoma (HPV-18), and 9/9 HSIL (7 HPV-16, 2 not typed); 2/2 LSILs were negative for high-risk HPV.

CONCLUSIONS:

In our experience, anal squamous neoplastic lesions in IBD are associated with HPV infection and SCC seem to be associated with perianal CD. Prospective studies are needed to confirm these results.

Unexpected anal squamous cells carcinoma after open hemorrhoidectomy

We report a case of unexpected anal squamous cells carcinoma found in hemorrhoidectomy specimen. The patient had a 3-year history of prolapsing hemorrhoids. A prolapsing hemorrhoid was present at eleven o'clock in lithotomy. Milligan-Morgan was performed and gross examination of the specimen was unremarkable. Histopathologic evaluation showed noninvasive squamous cells carcinoma. The present case report evidences the opportunity of routine histopathologic analysis of hemorrhoidal specimens particularly in case of long-standing prolapse. Questions arise in the option of those techniques where no specimens are collected or tissue is excised far from deceased area.

Non-colorectal intestinal tract carcinomas in inflammatory bowel disease: results of the 3rd ECCO Pathogenesis Scientific Workshop (II)

Patients with inflammatory bowel diseases (IBD) have an excess risk of certain gastrointestinal cancers. Much work has focused on colon cancer in IBD patients, but comparatively less is known about other more rare cancers. The European Crohn's and Colitis Organization established a pathogenesis workshop to review what is known about these cancers and formulate proposals for future studies to address the most important knowledge gaps. This article reviews the current state of knowledge about small bowel adenocarcinoma, ileo-anal pouch and rectal cuff cancer, and anal/perianal fistula cancers in IBD patients.

The risk of cancer in patients with benign anal lesions: a nationwide population-based study

OBJECTIVE

To evaluate the risk of cancer among patients diagnosed with hemorrhoids and benign anal inflammatory lesions.

METHODS

A population-based, retrospective cohort study was conducted that included patients diagnosed with hemorrhoids or benign inflammatory anal lesions (eg, anal fissure, fistula, and perianal abscesses) that were registered in the National Health Insurance Research Database in Taiwan between January 1, 2000 and December 31, 2010. Standardized incidence ratios (SIRs) were calculated to compare the cancer incidence of these patients to the general population.

RESULTS

During a median observation period of 6.23 years, 3080 cancers developed among 70,513 hemorrhoid patients, with a follow-up period of 438,425.6 person-years, entailing the SIR of 1.52 (95% confidence interval [CI], 1.47-1.58). Increased cancer risk (SIR 1.16; 95% CI, 1.11-1.21) was still noted even after excluding the first year of observation. Significant long-term risk for colorectal cancer (SIR 1.50; 95% CI, 1.35-1.66) and prostate cancer (SIR 1.40; 95% CI, 1.17-1.66) was observed after corrections were made for multiple comparisons. In contrast, there was no remarkable increase in cancer risk for patients with inflammatory anal lesions when cancers detected within the first year of diagnosis were excluded.

CONCLUSION

The presence of hemorrhoids is associated significantly with a long-term risk of developing colorectal cancer or prostate cancer. In contrast, benign inflammatory anal lesions do not appear to increase the risk of malignancy.

A systematic review of anal squamous cell carcinoma in inflammatory bowel disease

AIM

The aim of this systematic review was to determine the incidence, aetiology and clinical characteristics of anal squamous cell carcinomas (SCC) presenting in patients with inflammatory bowel disease.

METHOD

A systematic review of the literature was undertaken using Medline, Embase, Cochrane and Web of Science.

RESULTS

A total of 33 cases of anal SCC were described, 7 in ulcerative colitis (UC) and 26 in Crohn's disease (CD). The annual incidence of anal SCCs was 0.9/100,000 and 2.0/100,000 in patients with UC and CD respectively. The gender ratio in CD was 3M:17F with a median age of 42 years, the main presenting symptom was anal pain and 85% of CD cases had peri-anal disease. No studies described anal intra-epithelial neoplasia. The human papilloma virus was found to be positive in 2 out of 5 (40%) cases. The majority of patients (73%) with CD received radical surgery as their first line treatment. The cumulative overall and disease free survival in CD was 37 per cent at five years.

CONCLUSION

The findings of this review when contrasted with the data from cancer registries suggests that there is a higher incidence of anal SCC, an earlier age of presentation and poorer outcomes in patients with Crohn's disease compared to the general population implying a more aggressive neoplastic process. This review supports the hypothesis that peri-anal disease plays a contributing role in anal SCCs and as such targeted surveillance in patients with longstanding peri-anal disease should be considered.

Squamous cell carcinoma associated anal fistulas in Crohn's disease unique case report with literature review

Squamous cell carcinoma arising from perineal fistula in patients with Crohn's disease (CD) is a rare entity, with few reported cases in the literature making its clinical characterization troublesome. The outcome is poor following operative treatment as the malignancy of chronic perineal fistula in Crohn's disease is usually overlooked and tardily diagnosed. We present a unique case of a 47-year-old man with a 20-year history of chronic perineal fistula that was diagnosed with extensive perineal squamous cell carcinoma extending down to the right thigh. Computer tomography showed locally advanced disease with inguinal and lung metastasis. Treatment was consisted of diverting colostomy and palliative care. The patient died 3 months later. The clinical data and clinicopathological features of reported cases in the literature were reviewed.

Immunosuppressive disorders and risk of anal squamous cell carcinoma: a nationwide cohort study in Denmark, 1978-2005

Compromised immune function may increase the risk of anal squamous cell carcinoma (SCC). We examined the risk of anal SCC in patients with HIV infection and other chronic disorders associated with immunosuppression. A population-based cohort study was conducted using the Danish National Patient Registry and the Danish Cancer Registry (DCR). We identified all patients with a first-time hospital contact or procedure for HIV infection, solid organ transplantation or autoimmune disease or a first-time record of haematologic malignancy in the DCR, 1978-2005, and followed these for a subsequent anal SCC, starting follow-up 1 year after diagnosis of the index disease. Standardised incidence ratios (SIRs) were computed as the ratio of observed to expected numbers of anal SCCs, based on national age-, sex- and period-specific rates. Among 4,488 patients with HIV, we observed 21 anal SCCs with 0.3 expected (SIR: 81.1 (95% confidence interval (CI): 51.6-121.9)). Risk of anal SCC was markedly increased among 5,113 solid organ recipients (SIR: 14.4 (CI: 7.0-26.4)) and 30,165 patients with haematologic malignancies (SIR: 2.3 (CI: 1.1-4.2)) but only moderately increased among 242,114 patients with autoimmune diseases (SIR: 1.3 (CI: 1.0-1.6)). SIRs varied according to type of autoimmune disease and were high in patients with Crohn's disease (SIR: 3.1 (CI: 1.2-6.4)), psoriasis (SIR: 3.1 (CI: 1.8-5.1)), polyarteritis nodosa (SIR: 8.8 (CI: 1.5-29.0)) and Wegener's granulomatosis (SIR: 12.4 (CI: 2.1-40.8)). In conclusion, we found HIV infection, solid organ transplantation, haematologic malignancies and a range of specific autoimmune diseases strongly associated with increased risk of anal SCC.

Infection and cervical neoplasia: facts and fiction

Whilst there is strong evidence that human papillomavirus (HPV) is the principal aetiological agent in cervical neoplasia, some other sexually transmitted agents may either contribute or protect against cervical carcinogenesis, such as the herpes virus family (HSV), cytomegalovirus (CMV), Epstein-Barr virus (EBV), human immunodeficiency virus (HIV) or Chlamydia trachomatis (CT). Epidemiological studies suggest that HSV may have a role in cervical neoplasia, but there is no clear supportive experimental evidence. Serological studies have also failed to reveal a difference in the prevalence of antibodies to CMV and EBV between patients with cervical cancer and controls. However, longitudinal seroepidemiological studies have provided evidence that CT is an independent risk factor for the development of cervical squamous carcinoma and this association is serotype specific. The increased risk of cervical neoplasia in patients infected with HIV has been recognised for over a decade and HIV may interact with HPV either by alternating HPV gene transcription or by immunosuppression. Finally extensive experimental and limited epidemiological evidence suggests that adeno-associated viruses (AAV) may have antioncogenic activity in man and may protect against the development of cervical cancer. At present the mechanism of this action is unclear but may relate to AAV-induced regulation of HPV gene expression and the HPV life cycle. In this review we summarize the current literature relating to the associations and mechanisms of cervical carcinogenesis by each of these infectious microorganisms.

Squamous cell carcinoma arising from recurrent anal fistula

Here, we report on a patient with squamous cell carcinoma (SCC) arising from recurrent anal fistula. The patient was a 57-year-old woman who had 32-year history of having a recurrent perianal abscesses that ruptured spontaneously. Six months before her admission to our hospital, anal pain developed. She had no history of inflammatory bowel disease. Physical examination revealed three external fistulous openings at the two o'clock position, 2 cm from the anal verge. One internal opening in the lower rectum was found with proctoscopy. The patient underwent fistulectomy. Microscopic examination showed SCC arising from the anal fistula, which was accompanied by vessel invasion. The tumor was observed to be continuous from the external opening but was not exposed to the internal opening of the rectal mucosa. Because human papillomavirus (HPV) infection was suspected, immunohistochemical analysis was performed, but showed no HPV infection. Two weeks after fistulectomy, abdominoperineal resection with lymph node dissection was performed. Histopathological examination revealed no remnant cancer tissue or lymph node metastasis. She was discharged after surgery without complications. Eight years after the operation, she complained of constant pain during micturition. Urological examination revealed urinary bladder cancer, and transurethral resection of the bladder tumor was performed. Histopathological examination revealed transitional cell carcinoma of the urinary bladder. Two years later, the patient died of metastatic urinary bladder cancer, without recurrence of the fistula cancer. Because the patients mother had died of urinary bladder cancer and she herself had metachronous urinary bladder cancer in addition to fistula cancer, we investigated whether microsatellite instability (MSI) and chromosomal instability correlated with fistula cancer development. Immunohistochemical analysis of formalin-fixed, paraffin-embedded surgical tumor specimens for p53, MLH1, and MSH2 was performed. The tumor specimens showed no MLH1 expression but did show normal MSH2 expression. p53 was not expressed. Five microsatellite loci were examined using the tumor specimens to detect MSI, namely two loci with mononucleotide runs (i.e., BAT25 and BAT26) and three loci with dinucleotide repeats (i.e., APC, Mfd15, and D2S123). The tumor specimens showed alternations in the repeated sequences of two loci (i.e., BAT26 and D2S123). As a result, the tumor was classified as MSI-H (high) according to the Bethesda criteria. Our patient had MSI and one of the smallest reported SCCs arising from recurrent anal fistulae.

Carcinoma arising in enterocutan fistulae of Crohn's disease patients: description of two cases

Rarely, carcinoma arises from the fistulous tract of Crohn's disease. Adequate radiological examination often produces misleading pseudonegative findings. We reported two cases of fistula cancers treated with infliximab. The short time-span between the administration of this drug and the diagnosis of cancer makes the correlation between the two unlikely.

Elevated anal squamous cell carcinoma risk associated with benign inflammatory anal lesions

BACKGROUND

The association between benign anal lesions and anal cancer is still unclear. Few data from large cohort studies are available.

METHODS

We conducted a register based retrospective cohort study including 45,186 patients hospitalised for inflammatory anal lesions (anal fissures, fistulas, and perianal abscesses) as well as 79,808 haemorrhoid patients, from 1965 to 2002. Multiple record linkages identified all incident anal (squamous cell carcinoma only) and colorectal cancers through to 2002. Relative risk was estimated by standardised incidence ratio (SIR), the ratio of observed number of cases divided by that expected in the age, sex, and calendar year-matched general Swedish population.

RESULTS

There was a distinct incidence peak in the first three years of follow up among patients with inflammatory lesions. SIR then levelled off at around 3 and remained at this level throughout follow up (SIR during years 3-37 of follow up was 3.3 (95% confidence interval 1.8-5.7)). A similar initial incidence peak was observed among haemorrhoid patients but was confined to the first year; SIR was 2.8 in the second year, and then it decreased further and was close to unity in the following years (SIR during years 3-37 was 1.3 (95% confidence interval 0.7-2.1)). Among inflammatory lesion and haemorrhoid patients, a significantly increased risk of colorectal cancer was observed only in the first year after hospitalisation.

CONCLUSIONS

Inflammatory benign anal lesions are associated with a significantly increased long term risk of anal cancer. In contrast, haemorrhoids appear not to be a risk factor for this malignancy.

HPV in anal squamous cell carcinoma and anal intraepithelial neoplasia (AIN). Impact of HPV analysis of anal lesions on diagnosis and prognosis

BACKGROUND AND AIMS

Majority of cases of anal squamous cell carcinoma are human papilloma virus (HPV)-induced and result from anal intraepithelial neoplasia (AIN). This study was conducted to examine methods which may enable the routine diagnosis of HPV-induced changes in the anal rim and the consequences of such detection especially in view of a more sensitive diagnosis of AIN. Results were clinically correlated.

METHODS

The study included biopsy samples from 87 patients who had been diagnosed with the following disease patterns: 47 invasive anal carcinoma, 33 AIN of varying severity and seven condylomatous lesions. In 52 of these cases, a tumour was clinically suspected. All biopsies were retrospectively examined for microscopic indications of HPV infection. After microdissection, additional HPV analysis via PCR was carried out.

RESULTS

In 38 of 47 cases of anal carcinoma, HPV DNA could be detected via PCR (80.9%), the majority of which were HPV 16 (33/38=86.8%). In 29 of the 33 cases of AIN, HPV DNA was detected (87.9%), most of these in AIN III (15/16=93.8%). Histological markers of HPV infection were detected in all 87 cases.

DISCUSSION

In our series, the clinical diagnosis of the invasive anal carcinoma had a high sensitivity of 93.6%, with a specificity of 80%. The positive predictive value was 84.6%, and the negative predictive value 91.4%. In contrast, AIN had been detected clinically in none of the cases. In this situation, especially with high-risk patients, our findings recommend anal HPV screening in combination with anal cytology and anoscopy.

CONCLUSION

Based on our results, we urgently recommend for any histological report on excision of anal lesions to include a statement whether histological markers of HPV infection were detected. In individual cases, validation via HPV PCR must be considered.

Anal and rectal cancer in Crohn's disease

Several epidemiological studies have been published regarding the risk of Crohn's disease- associated colorectal cancer. The findings are, however, contradictory and it has been particularly difficult to obtain indisputable information on the incidence of cancer limited to the rectum and the anus. During 1987-2000 rectal or anal cancer was diagnosed in 335 patients in Sweden (153 males, 182 females). In other words, approximately 3 Crohn patients per million inhabitants were diagnosed with rectal or anal cancer every year during that time period which is 1% of the total number of cases. At diagnosis of cancer 36% were aged below 50 years and 58% below 60 years. Corresponding figures for all cases of anal and rectal cancer were 5% and 18%, respectively. Present knowledge from the literature implies that there is an increased risk of rectal and anal cancer only in Crohn's disease patients with severe proctitis or severe chronic perianal disease. However, the rectal remnant must also be considered a risk factor. Multimodal treatment is similar to that in sporadic cancer but proctectomy and total or partial colectomy is added depending on the extent of the Crohn's disease. The outcome is the same as in sporadic cancer at a corresponding stage but the prognosis is often poor due to the advanced stage of cancer at diagnosis. We suggest that six high-risk groups should be recommended annual surveillance after a duration of Crohn's disease of 15 years including extensive colitis, chronic severe anorectal disease, rectal remnant, strictures, bypassed segments and sclerosing cholangitis.

Clinical findings among young women with genital human papillomavirus infection

OBJECTIVE

The purpose of this study was to identify clinical signs and symptoms associated with detection of human papillomavirus (HPV) DNA in the female genital tract.

STUDY DESIGN

A total of 516 university students (18 to 24 years old) enrolled in a cohort study that included the collection of genital specimens for HPV DNA testing every 4 months for up to 4 years. Reported symptoms and objective clinical findings of women with and without HPV DNA were compared by multivariate analysis.

RESULTS

Acute and persisting HPV infections were not associated with discharge, itching, burning, soreness, or fissures. Clinical evidence of genital warts was statistically associated only with HPV types 6 and 11. Detection of any HPV DNA was associated with bacterial vaginosis (BV). Furthermore, a time lag analysis suggests that HPV infection usually precedes detection of BV.

CONCLUSION

Most women who acquire genital HPV infection are asymptomatic; some, however, are at increased risk for BV.

High prevalence of anal squamous intraepithelial lesions and squamous-cell carcinoma in men who have sex with men as seen in a surgical practice

INTRODUCTION

Anal high-grade squamous intraepithelial lesions are probable invasive anal squamous-cell cancer precursors, and although unproved, treatment of high-grade squamous intraepithelial lesions may prevent progression to anal squamous-cell cancer. Men who have sex with men are often treated for benign anorectal disorders without consideration given to the possibility of concurrent high-grade squamous intraepithelial lesions or anal squamous-cell cancer. We determined the prevalence of anal high-grade squamous intraepithelial lesions and anal squamous-cell cancer in an urban surgical practice of men who have sex with men referred for treatment of anal condyloma and other benign noncondylomatous anal disorders.

METHODS

One hundred thirty-one HIV-positive and 69 HIV-negative men who have sex with men referred for surgical treatment of presumed benign anorectal disease were evaluated by anal cytology, high-resolution anoscopy, and biopsy. Anal cytology and histology were reported with a modified Bethesda classification.

RESULTS

One hundred fifty-seven patients (79 percent) were referred for condyloma, 4 (2 percent) for anal squamous intraepithelial lesions (anal high-grade squamous intraepithelial lesions) diagnosed by primary care providers, and 39 (19 percent) for other benign anorectal disorders. One hundred forty-three patients (93 percent) had abnormal anal cytology, with 107 (54 percent) having high-grade squamous intraepithelial lesions on cytology. Biopsy results revealed 120 patients (60.0 percent) with high-grade squamous intraepithelial lesions and 5 patients (3 percent) with invasive squamous-cell carcinoma. Four of five men with anal squamous-cell cancer were HIV positive. Fourteen men (36 percent) who have sex with men referred for noncondylomatous benign anal disorders had high-grade squamous intraepithelial lesions, and three (8 percent) had anal squamous-cell cancer. High-grade squamous intraepithelial lesions and anal squamous-cell cancer were seen most often at the squamocolumnar junction.

CONCLUSIONS

Men who have sex with men referred for treatment of either condyloma or noncondylomatous benign anorectal disease had a high prevalence of anal high-grade squamous intraepithelial lesions and anal squamous-cell cancer. All men who have sex with men referred for treatment of benign anorectal disease should have high-resolution anoscopy and aggressive biopsy of all abnormal areas. Treatment of external lesions alone could miss high-grade squamous intraepithelial lesions or anal squamous-cell cancer.

Viral infections of the gastrointestinal tract

Acute gastroenteritis is common in adults. It can occur in institutional epidemics or epidemics of food-borne illness; in these cases, caliciviruses are the major cause of the condition. When acute gastroenteritis occurs in nonepidemic form, its causes are less clear. It may be due to caliciviruses or to the less common serotypes of childhood gastroenteritis viruses, such as rotavirus, astrovirus, and adenovirus. The pathogenesis of acute viral gastroenteritis is not completely understood. Old evidence suggests that mild villus damage is responsible, but new evidence indicates that active secretion and motility disturbance may be involved in the production of symptoms. Five common viruses can remain latent in gastrointestinal tissues and produce disease many years after initial infection. Two major herpesviruses, cytomegalovirus and herpes simplex virus, cause ulcerative disease of the gastrointestinal tract. This disease occurs in healthy persons but is more common and more severe in immunocompromised patients. Three other viruses--Epstein-Barr virus, human papilloma virus, and human herpesvirus-8--are implicated in benign and malignant proliferative diseases of the gastrointestinal tract. Epstein-Barr virus has been associated with immunoproliferative disease after transplantation and may also cause small-bowel and colonic lymphoma in healthy adults. It causes most AIDS-related lymphomas. Human papillomaviruses cause anorectal condyloma and anal cancer. Human herpesvirus-8 causes gastrointestinal Kaposi sarcoma.

Tobacco smoking as a risk factor in anal carcinoma: an antiestrogenic mechanism?

BACKGROUND

Human papillomavirus-associated anogenital carcinogenesis depends on poorly defined cofactors. Smoking was recently suggested to increase the risk of anal cancer more in premenopausal women than in postmenopausal women. Thus, we used our population-based anal cancer case-control study in Denmark and Sweden to test this hypothesis.

METHODS

Our study included 417 patients (324 women and 93 men) who were diagnosed with anal cancer (84% invasive cancer) from 1991 through 1994; it also included five patients diagnosed in 1995. Two control groups were used: 1) 554 population control subjects (349 women and 205 men) and 2) 534 patients with rectal adenocarcinoma (343 women and 191 men). Odds ratios (ORs), calculated from logistic regression analyses, were used as measures of relative risk. All P values are two-sided.

RESULTS

Compared with the risk for lifelong nonsmokers, the risk of anal cancer was high among premenopausal women who currently smoked tobacco (multivariate OR = 5.6; 95% confidence interval [CI] = 2.4-12.7) and increased linearly by 6.7% per pack-year smoked (one pack-year is equivalent to one pack of cigarettes smoked per day for 1 year) (P for trend <.001). Smoking was not statistically significantly associated with anal cancer risk in postmenopausal women or men. Women whose menstrual periods started late were at high risk (multivariate OR = 3.6; 95% CI = 1.8-7.3, for > or = 17 years of age versus < or = 12 years of age; P for trend <.001), and body mass index (weight in kg/[height in m]2) was inversely associated with risk among women (P<.001).

CONCLUSIONS

Because the risk of anal cancer associated with smoking was restricted to premenopausal women and because higher risk was associated with late menarche and lean body composition, female sex hormones may be a factor in anal cancer development in women. Since the anal mucosa is an estrogen-sensitive area, we hypothesize an antiestrogenic mechanism of action for smoking in anal carcinogenesis.