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- Adami, Hans-Olov, et al.
(författare)
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Pregnancy and risk of non-Hodgkin´s lymphoma : a prospective study
- 1997
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Ingår i: International Journal of Cancer. - 0020-7136 .- 1097-0215. ; 70:2, s. 155-158
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Tidskriftsartikel (refereegranskat)abstract
- The etiology of non-Hodgkin's lymphomas (NHL), including chronic lymphocytic leukemia (CLL), is likely to be related to immune function. In the light of the established immunologic effects of a pregnancy, we decided to examine the risk of NHL and CLL in relationship to full-term pregnancies. Within a nationwide cohort we identified 1,546 women with NHL and 198 women with CLL, all 15 years or older, born 1925-1972. Five age-matched controls were selected for each case patient. Conditional logistic regression was used to estimate the odds ratios after mutual adjustment for number of births and age at first birth. We found a weak, negative association between parity and risk of NHL (p for trend 0.11) and a transient, 10-40% decrease in risk within 5-14 years after the last birth among women with various parity status. The risk of CLL decreased more markedly, and orderly with increasing parity, but the trend was not significant (p = 0.18). Small numbers of cases with CLL prevented more detailed analyses of temporal relationships. Age at first birth appeared unrelated to the risk of both NHL and CLL. We conclude that the immunologic alterations associated with a pregnancy have limited, if any, relevance to the etiology of NHL and CLL; changing reproductive pattern is an unlikely contributor to the marked increase in incidence of NHL seen in many populations.
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| 2. |
- Frisch, Morten, et al.
(författare)
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Sexually transmitted infection as a cause of anal cancer
- 1997
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Ingår i: New England Journal of Medicine. - 0028-4793 .- 1533-4406. ; 337:19, s. 1350-1358
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The incidence of anal cancer has increased in recent decades, particularly among women. To identify underlying risk factors, we conducted a population-based case-control study in Denmark and Sweden. METHODS: We conducted telephone interviews with 324 women and 93 men in whom invasive or in situ anal cancer was diagnosed between 1991 and 1994, 534 controls with adenocarcinoma of the rectum, and 554 population controls. The interviews covered a wide spectrum of possible risk factors for anal cancer. Odds ratios were calculated by logistic regression. Specimens of anal-cancer tissue and samples of rectal adenocarcinomas were tested for human papillomavirus (HPV) DNA with the polymerase chain reaction. RESULTS: Multivariate analysis revealed consistent and statistically significant associations between measures of sexual promiscuity and the risk of anal cancer in both men and women. There was a significant trend toward an association between higher numbers of partners of the opposite sex in women (P<0.001) and men (P<0.05) and strong associations with a variety of venereal diseases. In women, receptive anal intercourse, particularly before the age of 30 years, and venereal infections in the partner were also associated with an increased risk (odds ratios, 3.4 and 2.4, respectively). Fifteen percent of the men with anal cancer reported having had homosexual contact, as compared with none of the controls (P<0.001). High-risk types of HPV, notably HPV-16, were detected in 84 percent of the anal-cancer specimens examined, whereas all rectal-adenocarcinoma specimens tested were negative for HPV. CONCLUSIONS: Our study provides strong evidence that a sexually transmitted infection causes anal cancer. The presence of high-risk types of HPV, notably HPV-16 (which is known to cause cancer of the cervix), in the majority of anal-cancer tissue specimens suggests that most anal cancers are potentially preventable.
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