Geographical clustering of anal cancer incidence in Australia.

INTRODUCTION: Homosexual men are at an increased risk of anal cancer. We aimed to establish the burden of anal squamous cell carcinoma (SCC) in those parts of Australia where homosexual men are most likely to live. METHODS: Data on the proportion of homosexual male residents were obtained from published estimates. Men were categorised into three postcode groups by prevalence of men reporting homosexual identity. Male population data in age groups were extracted for each postcode group and analyses of cancer incidence were performed by postcode group. The analyses were restricted to 2000-2005. RESULTS: Eight postcodes had populations where more than 10% of males reported homosexual identity (high prevalence) and 4-10% of men reported homosexual activity in a further 19 postcodes (medium prevalence). From 2000 to 2005, the average annual age-standardised incidence rates of anal SCC in males was 7.61 per 100000 (95% confidence interval (CI): 4.68-10.55) and 2.21 per 100000 (95% CI: 1.05-3.37) in high and medium prevalence postcodes, respectively. The corresponding incidence rate ratios compared with low prevalence postcodes (less than 4% of males reported homosexual identity) were 9.6 (95% CI: 6.6-14.1) for the high prevalence and 2.4 (95% CI: 1.4-4.1) for the medium prevalence postcodes. CONCLUSION: A substantial concentration of the burden of anal cancer occurred among areas where large proportions of homosexual men reside. These results should guide the prioritisation of health service investment in anal cancer treatment and prevention to appropriate geographical areas.

Quality of life valuations of HPV-associated cancer health states by the general population.

OBJECTIVES: To obtain health-related quality of life valuations (ie, utilities) for human papillomavirus (HPV)-related cancer health states of vulval, vaginal, penile, anal and oropharyngeal cancers for use in modelling cost-effectiveness of prophylactic HPV vaccination. METHODS: Written case descriptions of each HPV-associated cancer describing the 'average' patient surviving after the initial cancer diagnosis and treatment were developed in consultation with oncology clinicians. A general overview, standard gamble questionnaire for each health state and a quiz was conducted in 120 participants recruited from the general population. RESULTS: In the included population sample (n=99), the average age was 43 years (range = 18-70 years) with 54% men, 44% never married/43% married, 76% education beyond year 12 and 39% employed full-time. The utility values for the five health states were 0.57 (95% CI 0.52 to 0.62) for anal cancer, 0.58 (0.53 to 0.63) for oropharyngeal cancer, 0.59 (0.54 to 0.64) for vaginal cancer, 0.65 (0.60 to 0.70) for vulval cancer and 0.79 (0.74 to 0.84) for penile cancer. Participants demonstrated a very good understanding of the symptoms, diagnosis and treatment of these cancers with a mean score of 9 (SD=1.1) on a 10-item quiz. CONCLUSIONS: This study provides utility estimates for the specific HPV-related cancers of vulval, vaginal, penile, anal and oropharyngeal cancers valued by a general population sample using standard gamble. The results demonstrate considerable quality of life impact associated with surviving these cancers that will be important to incorporate into modelling cost-effectiveness of prophylactic HPV vaccination in different populations.

Trends in anal cancer in Australia, 1982-2005.

BACKGROUND: Most anal squamous cell carcinomas (SCCs) are caused by high risk types of human papillomavirus (HPV) and are potentially preventable by HPV vaccination. In order to understand the burden of potentially preventable anal cancer in Australia, we examine the incidence and survival from invasive anal SCC 1982-2005. METHODS: We reviewed data on invasive anal cancer cases notified to the National Cancer Statistics Clearing House. Age specific incidence rates of SCC were calculated by year of cancer diagnosis and by birth cohort, and rates of anal adenocarcinoma were included for comparison. Incidence rates were age standardised to the Australian 2001 standard population. Trends in relative survival of SCC were examined. RESULTS: During the study period, a total of 4615 invasive anal cancer cases were diagnosed and most (69.7%) were SCC. Annual incidence of SCC increased almost 50%, from 0.65 to 1.00/100,000. Incidence increased at all ages. The annual rate of increase was almost two-folder higher in men (3.42%, 95% CI 2.49-4.35) than in women (1.88%, 95% CI 1.18-2.58). Five-year relative survival increased by nearly 10% from 58.9% to 68.3% over the last 20 years. Younger patients and women had better survival. For anal adenocarcinoma, increases of borderline significance were seen in men and women. CONCLUSION: There is an increasing burden of anal SCC in Australia. The group with the highest incidence - homosexual men - are not likely to be protected under the current vaccination policy.

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.

Genital warts incidence and healthcare resource utilisation in Australia.

OBJECTIVES: To estimate for the first time the incidence and healthcare resource utilisation associated with genital warts (GW) in Australia prior to the human papillomavirus vaccination programme. METHOD: The authors analysed data from the nationally representative Bettering the Evaluation of Care and Health general practice cross-sectional programme and from the National Hospital Morbidity Database to estimate age-related incidence and community (non-hospital) and hospital-related costs (in 2009 Australian dollars) associated with medical treatment of GW. RESULTS: The authors estimated an annual incidence of 2.19 cases of GW per 1000 Australians (95% CI 1.88 to 2.49), with peak incidence in women aged 20-24 years at 8.61 cases per 1000 and in men aged 25-29 years at 7.40 cases per 1000. The estimated number of consultations per GW case was 2.9 (95% CI 2.5 to 3.3) for women and 2.8 (95% CI 2.3 to 3.2) for men. Ablative treatments in general practice were more common in men (60% of consultations) than in women (37% of consultations). In contrast, more women (16% vs 8%) were referred to specialists, and 75% of ablative procedures requiring hospitalisation were performed in women. The annual cost of management of GW is over A$14 million, with an estimated cost per treated case of A$251 for men and A$386 for women. CONCLUSIONS: GW impose a large health and cost burden on Australians. The national immunisation programme with the quadrivalent human papillomavirus vaccine has the potential to greatly reduce this burden, and future research measuring its impact is keenly anticipated.

Patterns of treatment of external genital warts in Australian sexual health clinics.

BACKGROUND: External genital warts are a common sexually transmitted viral disease. We describe the patterns of treatment for initial presentations of external genital warts (EGWs) in Australian sexual health centers. METHODS: This was a retrospective audit of 489 case notes from consecutive individuals who presented with a new diagnosis of EGWs to 1 of 5 major sexual health clinics in Australia. Eligibility criteria were consecutive patients aged 18 to 45 years inclusively, presenting with first ever episode of EGWs from January 1, 2004. Exclusion criteria were patients who were immunocompromised, including HIV infection, or enrollment in a treatment study for EGWs. RESULTS: The median age at presentation of women was 23.2 years and of men 26.8 years. One quarter (n = 127) of patients had another sexually transmitted infection diagnosed at presentation. Nearly half of the patients (n = 224) presented only once for treatment. Most often, patients were treated with a monotherapy (n = 382/489; 78%), usually cryotherapy (257; 53%). Staff applied treatment in 361 (74%) cases. There was wide variation across sites, possibly reflecting local policies and budgets. We found no difference in wart resolution (n = 292; 60%) by initial treatment chosen. CONCLUSIONS: The diagnosis and treatment of genital warts constitute a sizable proportion of clinical visits to the audited sexual health services and require a large input of staff time to manage, including the application of topical treatments. Our results help complete the picture of the burden of EGWs on Australian sexual health centers before the introduction of the HPV vaccine.

Herpes zoster burden of illness and health care resource utilisation in the Australian population aged 50 years and older.

Incidence of zoster and post-herpetic neuralgia (PHN) and associated health care resource utilisation were investigated in the Australian population aged > or =50 years, using general practice data from 2000 to 2006, and pharmaceutical prescribing, hospital morbidity and emergency department data from 1998 to 2005. Zoster and PHN incidence rates were estimated as approximately 10/1000 and 1.45/1000 persons, respectively, with antivirals prescribed for 73.5% of zoster cases. Estimated hospitalisation and emergency department visit rates were 0.67/1000 and 0.38/1000 persons, respectively. Management of zoster (including PHN) involved approximately 2.4 general practitioner consultations. Total costs to the health care system were estimated as approximately 32.8 million per year. The substantial burden of zoster and PHN highlights the potential benefit of zoster vaccination.