Is screening for anal cancer warranted in homosexual men?

Social Inequalities in Palliative Care for Cancer Patients in the United States: A Structured Review

OBJECTIVES

To identify patterns of access to and use or provision of palliative care services in medically underserved and vulnerable groups diagnosed with cancer.

DATA SOURCES

Google Scholar, PubMed, MEDLINE, and Web of Science were searched to identify peer-reviewed studies that described palliative care in medically underserved or vulnerable populations diagnosed with cancer.

CONCLUSION

Disparities in both access and referral to palliative care are evident in many underserved groups. There is evidence that some groups received poorer quality of such care.

IMPLICATIONS FOR NURSING PRACTICE

Achieving health equity in access to and receipt of quality palliative care requires prioritization of this area in clinical practice and in research funding.

Current Best Practices for Sexual and Gender Minorities in Hospice and Palliative Care Settings

Although several publications document the health care disparities experienced by sexual and gender minorities (SGMs), including lesbian, gay, bisexual, and transgender (LGBT) individuals,1e4 less is known about the experiences and outcomes for SGM families and individuals in hospice and palliative care (HPC) settings. This article provides a brief overview of issues pertaining to SGMs in HPC settings, highlighting gaps in knowledge and research. Current and best practices for SGM individuals and their families in HPC settings are described, as are recommendations for improving the quality of such care.

The bereavement experiences of lesbian, gay, bisexual and/or trans* people who have lost a partner: A systematic review, thematic synthesis and modelling of the literature

BACKGROUND

Socially excluded populations have poorer access to care; however, little attention has been paid to lesbian, gay, bisexual and/or trans* people. Lesbian, gay, bisexual and/or trans* people are at increased risk of certain life-limiting illnesses and may not receive the care and support they need at the end of life and into bereavement.

AIM

To identify and appraise the evidence of the bereavement experiences of lesbian, gay, bisexual and/or trans* people who have lost a partner and develop an explanatory model of lesbian, gay, bisexual and/or trans* partner bereavement.

DESIGN

Systematic review (in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines) and thematic synthesis with assessment of reporting and rigour. Quantitative or qualitative articles reporting bereavement experiences of lesbian, gay, bisexual and/or trans* partners were included, excluding articles reporting multiple losses in the context of HIV or AIDS.

DATA SOURCES

PsycINFO, MEDLINE, Web of Science, Scopus, Cochrane Library. Inclusion dates: database inception - 30 April 2015.

RESULTS

A total of 23 articles reporting on 13 studies were identified. Studies described universal experiences of the pain of losing a partner; however, additional barriers and stressors were reported for lesbian, gay, bisexual and/or trans* people, including homophobia, failure to acknowledge the relationship, additional legal and financial issues and the 'shadow' of HIV or AIDS. A novel model was developed to explain how the experience for lesbian, gay, bisexual and/or trans* people is shaped by whether the relationship was disclosed and acknowledged in life and into bereavement and how this impacts upon needs and access to care.

CONCLUSION

There is a need for healthcare providers to avoid hetero-normative assumptions; be mindful of additional stressors in bereavement for lesbian, gay, bisexual and/or trans* people; and consider additional sources of support to deliver individualised holistic care.

Anal Cancer Screening in Men Who Have Sex With Men in the Multicenter AIDS Cohort Study

OBJECTIVE

To evaluate the prevalence of anal cytology (ACyt) abnormalities among HIV-infected and HIV-uninfected men who have sex with men (MSM).

DESIGN

Multicenter cohort study of 723 HIV-infected and 788 HIV-uninfected MSM with ACyt, with a second ACyt collected 2 years later. A referral for high-resolution anoscopy was suggested for abnormal ACyt.

METHODS

ACyt samples were collected using a polyester swab and liquid cytology media and read in a central laboratory.

RESULTS

Prevalence of any abnormal ACyt was 25% in HIV-uninfected MSM and increased to 38%, 41%, and 47% among HIV-infected MSM with current CD4 T-cell counts ≥500, 350-499, and <350 cells/mm (P < 0.001), respectively. Anal HPV16 DNA was also more common in HIV-infected than HIV-uninfected MSM (25% versus 16%, P < 0.001). Abnormal baseline ACyt together with prevalent HPV16 DNA detection was present in only 7% of HIV-uninfected MSM compared to 18% of HIV-infected MSM with current CD4 < 350, P < 0.001. Among HIV-infected men, 56% of the men with atypical squamous cells of undetermined significance or low-grade squamous intraepithelial lesions ASCs-US/LSILs and 81% of men with atypical squamous cells cannot exclude high-grade (ASC-H/)/high-grade squamous intraepithelial lesions (HSIL) had lower grade ACyt findings 18-30 months later ("regressed"). However, 19% of untreated HIV-infected men with ASC-H/HSIL cytology maintained that same grade of cytology in their second test approximately 2 years later, and 15% with ASC-US/LSIL "progressed" to ASC-H/HSIL. Abnormal ACyt had high sensitivity (96%) but low specificity (17%) for biopsy-proven HSIL.

CONCLUSIONS

Prevalence of abnormal ACyt remains elevated in HIV-infected men during the current antiretroviral therapy era.

Regional and national guideline recommendations for digital ano-rectal examination as a means for anal cancer screening in HIV positive men who have sex with men: a systematic review

Background

Although anal cancer is common in HIV positive men who have sex with men, few centres offer systematic screening. Regular digital ano-rectal examination (DARE) is a type of screening that has been recommended by some experts. How widely this forms part of HIV management guidelines is unclear.

Methods

The protocol was registered prospectively (CRD42013005188; http://www.crd.york.ac.uk/PROSPERO/). We systematically reviewed 121 regional and national HIV guidelines and searched for guidelines from http://hivinsite.ucsf.edu/global?page=cr-00-04#SauguidelineX, PubMed and Web of Science databases up to 5^th August 2013 for recommendations of DARE as a means of anal cancer screening in HIV positive MSM. Guidelines were examined in detail if they were clinical guidelines, including both prevention and treatment protocols and were in English. Guidelines were excluded if they were restricted to limited areas (e.g. antiretroviral therapy only, children or pregnant women, strategies for prevention/testing). Information was extracted regarding recommendation of DARE as a screening method, the frequency of DARE recommended, target population for screening and the strength of evidence supporting this.

Results

30 regional and national guidelines were included and examined in detail. Only 2 recommended DARE. The ‘European AIDS Clinical Society Guidelines’ recommends DARE every 1–3 years for HIV positive MSM whilst the ‘US Guideline for prevention and treatment of opportunistic infections in HIV-infected adults and adolescents’ recommends an annual DARE for the HIV + population in general. None of these guidelines specify the age of commencing screening. In each case, the highest level of evidence supporting these two recommendations was expert opinion.

Conclusions

Few HIV guidelines discuss or recommend DARE as a means of anal cancer screening. Studies of the efficacy, acceptability and cost-effectiveness of DARE are needed to assess its role in anal cancer screening.

Uptake and predictors of anal cancer screening in men who have sex with men

OBJECTIVES

We investigated attitudes about and acceptance of anal Papanicolaou (Pap) screening among men who have sex with men (MSM).

METHODS

Free anal Pap screening (cytology) was offered to 1742 MSM in the Multicenter AIDS Cohort Study, who reported history of, attitudes about, and experience with screening. We explored predictors of declining screening with multivariate logistic regression.

RESULTS

A history of anal Pap screening was uncommon among non-HIV-infected MSM, but more common among HIV-infected MSM (10% vs 39%; P < .001). Most participants expressed moderate or strong interest in screening (86%), no anxiety about screening (66%), and a strong belief in the utility of screening (65%). Acceptance of screening during this study was high (85%) across all 4 US sites. Among those screened, most reported it was "not a big deal" or "not as bad as expected," and 3% reported that it was "scary." Declining to have screening was associated with Black race, anxiety about screening, and low interest, but not age or HIV status.

CONCLUSIONS

This study demonstrated high acceptance of anal Pap screening among both HIV-infected and non-HIV-infected MSM across 4 US sites.

Prevalence and predictors of high-grade anal intraepithelial neoplasia in a community-based sample of homosexual men

BACKGROUND

We report the prevalence and predictors for high-grade anal intraepithelial neoplasia (HGAIN) in community-based cohorts of HIV-negative and HIV-positive homosexual men in Sydney, Australia.

METHODS

A cross-sectional study of consecutive participants in both cohorts was performed in 2005 (204 HIV-negative and 128 HIV-positive men). Anal swabs collected by a research nurse underwent cytological analysis, using the ThinPrep procedure, and human papillomavirus (HPV) testing. Participants who had cytological abnormalities other than low-grade squamous epithelial lesions (SIL) were referred for high resolution anoscopy (HRA).

RESULTS

A total of 114 men had cytological abnormalities (24.3% of HIV-negative and 57.5% of HIV-positive men, odds ratio (OR)=4.21, 95% confidence interval (CI) 2.57-6.90). However, only three (2.3%) HIV-positive men and no HIV-negative men had high-grade SIL on anal cytology. Seventy-seven men were referred for HRA, of whom 63 (81.8%) attended. Histologically confirmed HGAIN was detected in 21 (33.3%). The prevalence of HGAIN was higher in HIV-positive men (10.8%) than in HIV-negative men (5.0%, OR=2.29, 95% CI 0.93-5.63, P=0.071). HGAIN was not related to age but was strongly associated with the detection of high-risk types of anal HPV (OR=10.1, 95% CI 1.33-76.2) rather than low-risk types (OR=1.97, 95% CI 0.74-5.25).

CONCLUSION

HGAIN was prevalent in homosexual men across all age groups and was more than twice as common in HIV-positive men compared with HIV-negative men. The presence of high-risk anal HPV was highly predictive of HGAIN.

HIV, cancer, and aging

As people with HIV age, they will experience increasing rates of all diseases of aging, including cancer. However, the pattern of higher cancer risk in people with HIV is mostly explained by the chronic effects of certain oncogenic infections, and is not consistent with a syndrome of accelerated aging. Many of those cancers that are most closely associated with aging do not occur at increased rates in people with HIV compared with the general population. The risk of many infection-associated cancers in people with HIV is closely related to the degree of immune deficiency, and for some types of cancer, it is also associated with ongoing HIV replication. Thus, if HIV therapy can provide durable HIV suppression and maintain near normal levels of immune function, the excess risk of cancer is likely to be minimised. While avoidance of profound immunity will greatly reduce cancer risk, it is unclear how close to normal immune function must be to minimise HIV-associated cancer risk. People with HIV are also at a high risk of cancer because they have high rates of lifestyle risks for cancer, in particular tobacco and alcohol exposure. For most cancers, it is appropriate to follow general population guidelines on cancer screening. The exception is cervical cancer, for which annual screening is recommended. In addition, active research is required to establish whether anal cancer screening would prevent the unacceptably high levels of morbidity caused by this disease in people with HIV, most particularly in gay men.

Four decades of anal cancer in Tasmania, Australia: what do the case data tell us?

Background Anal cancer is a rare cancer analogous to cervical cancer, largely caused by exposure to oncogenic human papillomavirus. We have sought to study this disease in the epidemiologically distinct population of Tasmania. Methods: Medical records at all tertiary and secondary referral centres in Tasmania were audited for records with corresponding International Classification of Diseases (ICD)-10 codes. Statistical significances of trends were evaluated using Fisher’s exact test, logistic regression or linear regression. Results: Of ~1350 screening records, 170 cases of anal cancer were found with patient presentation during 1973–2010, corresponding to 132 patients. This cohort was mostly female (66.7%), with squamous cell histology (81.8%) and anal canal primaries (72.0%). Most cases were detected at Stage II or below and the majority remained disease-free after treatment. Relatively few cases had documentation of typical risk factors for anal cancer, such as HIV seropositivity, a history of cancer or smoking. After 2000, there was a trend towards a lower stage at presentation, correlating with an increased 5-year survival. After 2000, no anal margin tumours presented beyond Stage II; nearly half were detected in situ and none were fatal. For anal canal tumours, there was virtually no change in the mean stage at detection or in survival. Conclusion: This is the first case series of anal cancer in Tasmania. We find that in many ways, including symptoms and pathology at presentation, epidemiology is typical. However, our cohort is distinct in its paucity of known risk groups, including HIV-positive people, those with a history of cancer and smokers.

Review of HIV-Related Cytopathology

Exfoliative and aspiration cytologies play a major role in the management of patients with human immunodeficiency virus infection. Common cytology samples include cervicovaginal and anal Papanicolaou tests, fine needle aspirations, respiratory specimens, body fluids, Tzanck preparations, and touch preparations from brain specimens. While the cytopathologists need to be aware of specific infections and neoplasms likely to be encountered in this setting, they should be aware of the current shift in the pattern of human immunodeficiency virus-related diseases, as human immunodeficiency virus patients are living longer with highly active antiretroviral therapy and suffering fewer opportunistic infections with better antimicrobial prophylaxis. There is a rise in nonhuman immunodeficiency virus-defining cancers (e.g., anal cancer, Hodgkin's lymphoma) and entities (e.g., gynecomastia) from drug-related side effects. Given that fine needle aspiration is a valuable, noninvasive, and cost-effective tool, it is frequently employed in the evaluation and diagnosis of human immunodeficiency virus-related diseases. Anal Papanicolaou tests are also increasing as a result of enhanced screening of human immunodeficiency virus-positive patients for cancer. This paper covers the broad spectrum of disease entities likely to be encountered with human immunodeficiency virus-related cytopathology.

Cancers attributable to human papillomavirus infection

Although the human papillomavirus (HPV) vaccine was introduced primarily as a cervical cancer prevention vaccine, HPV has a causal role in several types of cancer. This article reviews the epidemiological evidence for the role of HPV in human cancer, and describes Australian trends in these cancers. HPV is a necessary cause of cervical cancer. The currently vaccine-preventable subtypes of HPV 16 and 18 are responsible for ~70% of cervical cancer. The introduction of an organised Pap smear program in Australia led to a steep decline in incidence over the past decades. HPV can be detected in ~40% and 70% of vulval and vaginal cancers respectively. Rates of these cancers have been stable over the past 20 years. The prevalence of HPV in penile cancer is ~50% and incidence has not recently changed. For anal cancer, ~85% of cases are HPV positive, and incidence has increased significantly in both men and women over the past 20 years. In the oral cavity, ~35% of oropharyngeal cancers and ~25% of other oral cavity cancers are HPV positive. The incidence of HPV-related oral cavity and oropharyngeal cancers is increasing, whereas incidence at HPV-unrelated sites is decreasing. Overall, 1154 HPV-related cancer cases were potentially preventable by vaccination. If HPV-related cancers at non-cervical sites are prevented by vaccination, then a similar number of cancer cases will be prevented as in the cervix. However, almost one-quarter of the potentially preventable cancer cases are in men, who are not included in the current national immunisation program.

A randomized, placebo-controlled, dose-escalation study to determine the safety, tolerability, and immunogenicity of an HPV-16 therapeutic vaccine in HIV-positive participants with oncogenic HPV infection of the anus

OBJECTIVE

Study aimed to assess safety, tolerability, and immunogenicity of novel therapeutic HPV-16 E6E7 ISCOMATRIX vaccine for treatment of human papilloma virus (HPV)-related anal intraepithelial neoplasia in HIV-infected men who have sex with men with moderate immunosuppression.

DESIGN

Randomized, multicenter, blinded, placebo-controlled, dose-escalating study investigating 3 different doses of vaccine and different dose schedule. Primary objective to determine safety and tolerability, including clinical status, maintenance of virological control, and CD4 cell count for more than 252 days.

RESULTS

Thirty-five men who have sex with men enrolled; median age 47 years; current CD4 count 627 cells per milliliter; nadir CD4 count 154 cells per milliliter; 94% current antiretrovirals; 100% high-risk HPV types; 69% abnormal anal cytology; and 34% anal intraepithelial neoplasia 1-3 on high-resolution anoscopy. No dose-limiting toxicities or serious adverse events in HPV-16 vaccine recipients. Most HPV-16 vaccine recipients reported moderate/severe short-term injection site reactions and systemic reactions including headache, myalgia, and fatigue. CD4 cell counts remained stable. Five participants had transiently detectable viral loads. Ninety-six percent of vaccine recipients had at least a 4-fold increase in HPV-16 antibody from prevaccination levels. Seventy-one percent had at least a 3-fold increase in interferon-gamma responses to E6E7 peptides.

CONCLUSIONS

The novel therapeutic HPV-16 E6E7 ISCOMATRIX vaccine seemed safe and reasonably well tolerated. The therapeutic vaccine induces strong and durable antibody responses and moderate interferon-gamma levels that fell to prevaccination levels by week 24.

Non-AIDS-defining malignancies in HIV-infected persons: etiologic puzzles, epidemiologic perils, prevention opportunities

Non-AIDS-defining malignancies have come to represent a growing fraction of the overall cancer burden in HIV-infected people, as improvements in HIV therapy prolong survival and reduce the incidence of AIDS-associated cancers. This review focuses on five non-AIDS-defining malignancies for which HIV-infected persons have an elevated risk, for which risk is substantial or increasing over time, and for which HIV infection may play an etiologic role. Among HIV-infected persons, lung cancer risk is high, in part due to frequent tobacco use in this population. Risks of anal cancer and liver cancer are also elevated, related to the high prevalence of infections with human papillomavirus and hepatitis B and C viruses. In addition, risk is elevated for Hodgkin lymphoma and several rare skin cancers, including Merkel cell carcinoma and sebaceous carcinoma. For anal cancer and Hodgkin lymphoma, it is particularly concerning that incidence in HIV-infected persons has risen in recent years, when highly active antiretroviral therapy has been available. Accumulating evidence supports the possibility that the high prevalence of known carcinogenic exposures (e.g., tobacco) and infections with oncogenic viruses does not completely explain the occurrence of these cancers. Indeed, HIV may act to increase the risk for each of these five non-AIDS-defining malignancies, although the mechanisms may vary, including immunosuppression, immune reconstitution, and chronic inflammation. These non-AIDS-defining cancers also present important opportunities for prevention (e.g., smoking cessation), screening (e.g., periodic anal Pap smear screening), and early detection.

Anal cancer screening behaviors and intentions in men who have sex with men

BACKGROUND

The incidence of anal cancer has increased in the past decade, especially among men who have sex with men (MSM) and HIV-infected individuals. There is controversy about whether to routinely screen for anal cancer in MSM.

OBJECTIVES

To determine whether current anal cancer screening behaviors, intention, and concern differ by HIV serostatus and to identify characteristics of men who intend to seek anal cancer screening.

DESIGN AND PARTICIPANTS

Cross-sectional analysis of data collected from 901 HIV-infected and 1,016 HIV-uninfected MSM from the Multicenter AIDS Cohort Study (MACS) in 2005-2006.

MEASUREMENTS

Self-reported anal cancer screening history, attitudes, and intentions.

RESULTS

A history of anal warts was relatively common in these men (39%), whereas having a recent anal Pap test (5%), intention to seek anal cancer screening in the next 6 months (12%), and concern about anal cancer (8.5%) were less common. Intention to seek anal cancer screening was associated with enabling factors (screening availability, health insurance), need factors (HIV-infection, history of anal warts), concern about anal cancer, and recent sexual risk taking. Among four large US cities, there was significant regional variability in anal cancer screening behaviors, intention, and concern (all p<0.001). Most MSM (76%) indicated they would go to their primary care physician for an anal health problem or question.

CONCLUSIONS

This study demonstrates a low rate of anal cancer screening and intention to screen among MSM. As more evidence emerges regarding screening, primary care physicians should be prepared to discuss anal cancer screening with their patients.

Sexual diversity, social inclusion and HIV/AIDS

Despite a number of programmes to prevent HIV among men who have sex with men (MSM) and, more generally, sexually diverse populations, gay and other homosexually active men continue to be at heightened risk of HIV and its consequences. This paper analyses some of the reasons for this situation and offers policy and programmatic recommendations to contribute to a solution. The social exclusion of MSM and transgender individuals is an overwhelming reality in the majority of countries worldwide. Although progress has been achieved in some countries, in most of the world the situation remains problematic. Present challenges to equality and to the realization of health, include the membership of groups or subcultures with high HIV prevalence, lower quality and coverage of services and programmes and the impact of higher-level influences such as laws, public policies, social norms and culture, which together configure an environment that is hostile to the integration and needs of certain groups. A social inclusion perspective on HIV prevention and AIDS-related care implies the adoption of strategies to understand and confront social vulnerability. Sexual exclusion intensifies the burden of HIV transmission and morbidity. As part of a comprehensive response there is an urgent need to: (i) improve our understanding of the characteristics and HIV burden among sexually diverse populations; (ii) creatively confront legal, social and cultural factors enhancing sexual exclusion; (iii) ensure the provision of broad-based and effective HIV prevention; (iv) offer adequate care and treatment; and (v) confront special challenges that characterize work with these populations in lower and middle-income countries.

Early impact and performance characteristics of an established anal dysplasia screening program: program evaluation considerations

BACKGROUND

Screening for invasive anal cancer and its precursors is being increasingly advocated as a response to increasing incidence among HIV-infected persons. We implemented a comprehensive screening program in 2001 and report our early experience to inform monitoring and evaluation of such programs. Our research aims were: (1) to estimate incidence of and mortality from invasive anal cancer (IAC) before (1995-2000) and after (2001-2005) screening program implementation and (2) to examine potential screening program quality indicators.

METHODS

The study cohort included all patients under care for HIV infection at UCSD Owen Clinic between 1995-2005. Person-time incidence rates (IR) and case survival of IAC were estimated for the pre-screening (1995-2000) and post-screening (2001-2005) periods. High resolution anoscopy (HRA) operator accuracy was estimated by kappa agreement between cyto-histologic comparisons. Program quality indicators included: (1) screening coverage; (2) percent technically unsatisfactory cytology smears; (3) time between 1st abnormal cytology and 1st HRA; and (4) time between last clinic visit and last cytology.

RESULTS

28 cases of IAC and 13,411 person-years were observed between 1995-2005. IRs (95% CI) pre-screening and post-screening were 199 and 216 per 100,000 person-years, respectively. There was no routine treatment of high grade squamous intraepithelial lesions (HSIL) during the study period. The percent of patients with IAC requiring chemoradiation decreased from 90.9% to 70.6% (p=0.36). There was a significant improvement in cyto-histologic agreement at HRA with increasing operator experience (r=0.92, p=0.025). Screening coverage was 73% of the target population. Among 14 providers, the percent unsatisfactory cytology smears averaged 27% but varied from 0 - 62%. The median time from 1st abnormal cytology to 1st HRA was 258 days. The median interval between the last cytology and the last clinic visit was 207 days.

CONCLUSION

(1) The overall IR of IAC did not decline in the screening era and was higher than previous estimates for HIV cohorts; (2) stage shift to IAC of more favorable prognosis is a reasonable screening goal; (3) HRA accuracy varied by provider experience; (4) because of delay in access to HRA, digital rectal exam should be combined with cytology screening to detect palpable disease.

What do gay men know about human papillomavirus? Australian gay men's knowledge and experience of anal cancer screening and human papillomavirus

OBJECTIVE

The objective of this study was to determine levels of experience and knowledge concerning anal dysplasia, anal Pap smear tests, and human papillomavirus (HPV) among gay and other homosexually active men.

STUDY DESIGN

Three hundred eighty-four men attending a large gay community event in Melbourne completed a short survey.

RESULTS

Ninety-two percent identified as gay and 4.8% as bisexual. A total of 6.4% were HIV-positive and a further 3.5% did not know their HIV status. On a range of measures, it was clear that the men knew very little about anal cancer (19% scored zero on a 12-point knowledge scale) and virtually nothing about HPV (47% scored zero on an 8-point knowledge scale). A total of 55.1% had never heard of an anal Pap smear and 44.8% had ever heard of HPV; 56.4% did not know whether it affected men and/or women.

CONCLUSIONS

The test for anal dysplasia is still largely unknown among Australian gay men and they currently have poor sense of personal susceptibility to the disease. Health education strategies are suggested to improve this situation.

The lack of cancer surveillance data on sexual minorities and strategies for change

OBJECTIVE

To consider options for gathering cancer incidence and risk factor data in sexual minority individuals.

METHODS AND RESULTS

Sexual minority individuals may experience cancer risk disparities, due to lifestyle and reproductive differences compared with heterosexual people. However, cancer registry systems do not routinely collect sexual minority status. Other methods of obtaining such data and comparing cancer rates and risks between sexual minority and heterosexual people are discussed. These include building on existing registry membership with a targeted survey, using existing data sources, and estimating sexual orientation status with related data.

CONCLUSIONS

Efforts described here could provide support for or refute the hypothesis that disparities exist in selected cancer rates in sexual minority populations and could guide targeted efforts to reduce any disparities.

Increasing incidence of squamous cell carcinoma of the anus in Scotland, 1975-2002

In Scotland, since 1975–1979 (world) age-standardised incidence of squamous cell carcinoma of the anus has more than doubled, reaching 0.37 per 100 000 in males and 0.55 in females during 1998–2002, being somewhat higher in socioeconomically deprived areas.