tailieunhanh - Cancer of the Anus

The European Union’s CAREX database of occupational exposures to carcinogens estimated that in the early 1990s 22-24 million workers in the then 15 EU member states were exposed to carcinogens classified as group 1 by the International Agency for Research on Cancer – those known to cause cancer in humans. Overall, 32 million workers, 23 per cent of the working population, had workplace exposures associated by the CAREX database with an occupational cancer risk. The most common exposures were solar radiation, environmental tobacco smoke, crystalline silica, radon and wood dust. That over 1 in 5 workers face a. | Chapter 5 Cancer of the Anus Margaret M. Madeleine and Laura M. Newcomer INTRODUCTION Anal cancer includes tumors of the anus anal canal and anorectum. The anal canal extends from the rectum to the perianal skin and it is lined by a mucous membrane that covers the interior anal sphincter 1 2 . It is a rare disease with an annual age-adjusted incidence rate of per 100 000 people in the . 3 . Approximately 4 660 new cases and 660 deaths from anal cancer are expected in the . annually 4 . Although both sexes have seen an increase in incidence in recent years this rise has been more pronounced in men. Oncogenic human papillomavirus HPV types the same HPV types found to cause cervical cancer have been detected in the majority of anal tumors 5 . Epidemiologic studies suggest that in addition to infection with HPV smoking is a major risk factor for anal cancer in men and women also men who have sex with men are at a particularly increased risk of anal cancer 6-8 . Small tumors of the anal margin not including the anal sphincter are usually treated by wide local incision however tumors of the anal canal that involve the anal sphincter or that are too large for excision are treated by radiation or combination chemotherapy and radiation 9 . In this report we use . SEER registry data to explore the impact of demographic and tumor characteristics on anal cancer survival. MATERIALS AND METHODS Between 1988 and 2001 6 411 patients with primary invasive anal cancer were diagnosed in the SEER catchment area. The following cases were excluded from the analysis patients for whom anal cancer was not the first primary cancer cases identified through autopsy or death certificate only those with unknown race cases without active follow-up or alive with no survival time patients less than 20 years old cases without microscopic confirmation and tumors identified as in situ lesions sarcomas or carcinoids. After these exclusions 4 296 adult cases remained for analysis Table