Summary Anal cancer is a rare tumour in Britain and its epidemiology has not previously been studied in this country. Several studies from the United States have shown an association between single marital status at the time of tumour registration (as a marker of male homosexuality in these populations) and the incidence of anal cancer. This study has used registry information on martial status for anal cancer The registrations for anal and colonic cancers were tabulated, by gender, marital status (single, married, divorced, separated, widowed, unknown) and 5-year age group. Colonic cancer was chosen as the control disease as there is no suggestion that a sexually transmissible agent is involved in its aetiology and it has been used previously as the control in a similar study (Daling et al., 1987). Carcinomas arising in the rectum and at the rectosigmoid junction were excluded as it could be hypothesized that the rectum may be subjected to similar sexually transmissible carcinogens as the anus, but it seems unlikely that this argument could apply to the whole of the colon.Anal tumours classified as 'anal canal' or 'anus, unspecified' (ICD 9 codes 154.2 and 154.3) were requested from the Registry computers. Since the literature on anal cancer is confused about the distinction between the anal canal and the perianal skin, tumours classified as perianal skin (ICD 9 codes 172.5 and 173.5) were excluded as these codes include a heterogeneous group of tumours whose sites could not be accurately ascertained.Marital status at tumour registration was divided into two broad groups, 'never married' (single) in contrast to 'ever married' persons (married, separated, divorced or widowed). Those individuals whose marital status was unknown were excluded from the analysis. Odds ratios (OR) were computed by the Mantel Haenszel procedure (Armitage, 1985) and their significance was estimated by a normal approximation. Approximate 95% confidence levels (CI) were computed by a normal approximation to the log odds ratio.Patients for whom the Thames Registry had no information on marital status were identified and an attempt was made to ascertain their marital status from death certificates. Also, the accuracy of marital status records in the Thames Registry was checked by comparison with death certificates for a sample of the registrations of anal and colon cancers whose marital status was apparent from the Registry information. ResultsThe results for all three Registries are shown in Figure 1. From 1975From to 1987 Although a similar trend was seen in all three Registries, the magnitude was greatest in the Thames Registry, in which the odds ratio for anal cancer was 2.8 in 'never married' men compared to 'ever married' men with a 95% confidence interval of 2.1-3.8. The risk was similar for men under the age of 50 to that in older men. For women, never married individuals had a risk of 0.5 (95% confidence interval 0.3-0.7), with no clear differences according to age (Table I).

Thyroid cancer incidence and related mortality is increasing year-on-year, and although treatment for early disease with surgery and radioiodine results in a 98% 5-year survival rate, recurrence and treatment refractory disease is evident in an unacceptable number of patients. Alternative treatment regimens have therefore been sought in the form of tyrosine kinase inhibitors, immunotherapy, vaccines, chimeric antigen receptor T-cell therapy and oncolytic viruses. The current review aims to consolidate knowledge and highlight the latest clinical trials using secondary therapies in thyroid cancer treatment, focusing on both in vitro and in vivo studies, which have investigated therapies other than radioiodine.