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- Frisch, Morten, et al.
(författare)
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Benign anal lesions, inflammatory bowel disease and risk for high-riskive and -negative anal carcinoma
- 1998
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Ingår i: British Journal of Cancer. - 0007-0920 .- 1532-1827. ; 78:11, s. 1534-1538
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Tidskriftsartikel (refereegranskat)abstract
- A central role in anal carcinogenesis of high-risk types of human papillomaviruses (hrHPV) was recently established, but the possible role of benign anal lesions has not been addressed in hrHPV-positive and -negative anal cancers. As part of a population-based case-control study in Denmark and Sweden, we interviewed 417 case patients (93 men and 324 women) diagnosed during the period 1991-94 with invasive or in situ anal cancer, 534 patients with adenocarcinoma of the rectum and 554 population controls. Anal cancer specimens (n = 388) were tested for HPV by the polymerase chain reaction. Excluding the 5 years immediately before diagnosis, men, but not women, with anal cancer reported a history of haemorrhoids [multivariate odds ratio (OR) 1.8; 95% confidence interval (CI) 1.04-3.2] and unspecific anal irritation (OR 4.5; CI 2.3-8.7) significantly more often than controls. Women with anal cancer did not report a history of benign anal lesions other than anal abscess to any greater extent than controls, but they had used anal suppositories more often (OR 1.5; CI 1.1-2.0). Patients with hrHPV in anal cancer tissue (84%) and those without (16%) reported similar histories of most benign anal lesions, but anal fissure or fistula was more common among hrHPV-positive cases. Ulcerative colitis and Crohn's disease, reported by <1% of study participants, were not associated with anal cancer risk. The higher proportion of hrHPV-positive anal cancers among case patients with anal fissure or fistula suggests that such mucosal lesions may provide direct viral access to basal epithelial layers. Since risk associations with benign anal lesions in men may be confounded by unreported sexual behaviour, and since risk associations in women were generally negative, it seems unlikely that benign anal lesions act as promoters in hrHPV-associated anal carcinogenesis. Moreover, benign anal lesions appear not to be linked to an alternative, hrHPV-unassociated causal pathway to anal cancer. Ulcerative colitis and Crohn's disease were not supported as causal factors for anal cancer.
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| 2. |
- Frisch, Morten, et al.
(författare)
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Tobacco smoking as a risk factor in anal carcinoma : an antiestrogenic mechanism?
- 1999
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Ingår i: Journal of the National Cancer Institute. - : Oxford University Press (OUP). - 0027-8874 .- 1460-2105. ; 91:8, s. 708-715
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Human papillomavirus-associated anogenital carcinogenesis depends on poorly defined cofactors. Smoking was recently suggested to increase the risk of anal cancer more in premenopausal women than in postmenopausal women. Thus, we used our population-based anal cancer case-control study in Denmark and Sweden to test this hypothesis. METHODS: Our study included 417 patients (324 women and 93 men) who were diagnosed with anal cancer (84% invasive cancer) from 1991 through 1994; it also included five patients diagnosed in 1995. Two control groups were used: 1) 554 population control subjects (349 women and 205 men) and 2) 534 patients with rectal adenocarcinoma (343 women and 191 men). Odds ratios (ORs), calculated from logistic regression analyses, were used as measures of relative risk. All P values are two-sided. RESULTS: Compared with the risk for lifelong nonsmokers, the risk of anal cancer was high among premenopausal women who currently smoked tobacco (multivariate OR = 5.6; 95% confidence interval [CI] = 2.4-12.7) and increased linearly by 6.7% per pack-year smoked (one pack-year is equivalent to one pack of cigarettes smoked per day for 1 year) (P for trend <.001). Smoking was not statistically significantly associated with anal cancer risk in postmenopausal women or men. Women whose menstrual periods started late were at high risk (multivariate OR = 3.6; 95% CI = 1.8-7.3, for > or = 17 years of age versus < or = 12 years of age; P for trend <.001), and body mass index (weight in kg/[height in m]2) was inversely associated with risk among women (P<.001). CONCLUSIONS: Because the risk of anal cancer associated with smoking was restricted to premenopausal women and because higher risk was associated with late menarche and lean body composition, female sex hormones may be a factor in anal cancer development in women. Since the anal mucosa is an estrogen-sensitive area, we hypothesize an antiestrogenic mechanism of action for smoking in anal carcinogenesis.
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