An analysis of temporal and generational trends in the incidence of anal and other HPV-related cancers in Southeast England

Abstract

Patients diagnosed in 1960 -2004 with cancer of the cervix, anus, vulva, vagina or penis were identified from the Thames Cancer Registry database, and age-standardised period (temporal) incidence rates calculated by direct standardisation. Age-cohort modelling techniques were used to estimate age-specific incidence rates in the earlier and later cohorts, enabling the calculation of agestandardised cohort (generational) rates. Incidence of anal cancer increased for both men and women over the period studied, mainly in those born from 1940 onwards. Similar generational patterns were seen for cancers of the vulva and vagina, but those for penile cancer were different. For cervix cancer, the steep downward trend in cohort rates due to screening levelled off in women born from 1940 onwards. Our findings are compatible with the hypothesis that changes in sexual practices were a major contributor to the increases of these cancers. Programmes of vaccination against HPV, aimed at reducing the burden of cervical cancer, may also help to reduce the incidence of cancer at other anogenital sites. (Daling and Sherman, 1992;Frisch et al, 1997;Daling et al, 2004; Bjørge et al, 2002), vulva and vagina (Madeleine et al, 1997; Daling et al, 2002;Goffin et al, 2006;Madsen et al, 2008). Cancers of the anus, vulva and vagina occur more frequently than expected following cervical intraepithelial neoplasia III or invasive cervical cancer, suggesting a strong common aetiological factor (Evans et al, 2003). HPV infection may also play a role in a subset of penile squamous cell carcinomas (Iwasawa et al, 1993;Rubin et al, 2001; Daling et al, 2005;Heideman et al, 2007;Tornesello et al, 2008).Increasing trends in anal cancer have been reported, possibly due to changes in sexual practices (Daling et al, 1987;Scholefield et al, 1990;Frisch et al, 1993Frisch et al, , 1997. If this were the case, a strong generational effect would be expected in the incidence trends of anogenital cancers. We have explored this hypothesis by plotting age-standardised period (temporal) and cohort (generational) rates for cancer sites linked to HPV infection. (World Health Organization, 1976), and were retrospectively recoded to the ICD-10 classification in the case of tumours diagnosed before its introduction in the early 1990s. Examination of proportional frequency plots revealed no coding discrepancies or inconsistencies over the period of the study. Age at diagnosis was categorised into 5-year groups (0 -4, 5-9, y, 80 -84, 85 þ ), and period of diagnosis into 5-year periods (1960 -1964, 1965 -1969, y, 2000 -2004). Nominal birth cohort groups (1875, 1880, y, 2000) were then calculated by subtracting the midpoint of the age group from the midpoint of the period. For each site, an age-standardised incidence rate for each calendar period was calculated by direct standardisation, using the European standard population. As the earlier and later birth cohorts were missing data from the younger and older age groups, respectively, a Poisson regression age-cohort m...

Trends in incidence of anal cancer and high‐grade anal intraepithelial neoplasia in Denmark, 1978–2008

“…5 In recent studies of women and men from the general population in Denmark in the age group 18-45 years, a high proportion of women (30%) and men (43%) reported having had more than 10 lifetime partners, 23,24 and surveys in Denmark and Scotland indicate that the prevalence of receptive anal intercourse tends to be higher in women than in men, which might be one of the explanations for the higher incidence of anal cancer in women. 20,25 Our finding that the incidence of anal cancer was increased particularly among younger people is in line with the report of Robinson et al, 21 who compared estimated agespecific incidence rates of anal cancer in different birth cohorts. They found that the incidence of anal cancer increased mainly in the cohorts born around 1940 and Epidemiology onwards.…”

“…This is in line with reports from the USA of increases in incidence in periods between 1940 and 2003 3,4,[16][17][18][19] and from other European countries. [20][21][22] As in the 2 most recent European studies, we observed that the increase was particularly evident in women. 20,21 In Scotland, the incidence of squamous cell carcinoma in men tended to decrease or plateaued from the late 1990s onwards.…”

“…[20][21][22] As in the 2 most recent European studies, we observed that the increase was particularly evident in women. 20,21 In Scotland, the incidence of squamous cell carcinoma in men tended to decrease or plateaued from the late 1990s onwards. 20 Studies in the area of San Francisco (USA) suggest that most of the increase in anal cancer in men is attributable to the increased risk of men who have sex with men.…”

Estimates of thyroid cancer incidence in Brazil: an approach using polynomial models

“…Ignoring the effects of age and birth cohort (data not shown), we obtained estimates for thyroid cancer incidence rates of 1.34 for men and 6.3 for women (per 100,000 inhabitants), which were, respectively, 13% and 16% higher than those obtained when polynomial models were used. Approaches that consider age and birth cohort effects also proved relevant in estimating incidence rates for cancers of the breast and lung, among others 9,10 .…”

The case of the lady who risked exploding: A study of multiple consequences and contested values

“…The anal cancer diagnostic category bifurcates an overlap with more prevalent, less treatable rectal cancers. Anal cancer is uncommon, with an overall annual incidence of about 1 per 100,000 reported in England (Robinson, Coupland and Møller, 2009) and elsewhere. However, global incidence is increasing rapidly, probably through greater sexual transmission of the human papilloma virus (HPV) iii and immunodeficiency resulting from the spread of HIV and medical use of immunosuppresants (Ryan, Compton and Mayer, 2000).…”