Ovarian cancer risk factors: Difference between revisions
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"Associations were also found between alcohol consumption and cancers of the ovary and prostate, but only for 50 g and 100 g a day."<ref>[http://www.jr2.ox.ac.uk/bandolier/booth/hliving/alccan.html Alcohol consumption and cancer risk]</ref> | "Associations were also found between alcohol consumption and cancers of the ovary and prostate, but only for 50 g and 100 g a day."<ref>[http://www.jr2.ox.ac.uk/bandolier/booth/hliving/alccan.html Alcohol consumption and cancer risk]</ref> | ||
Risk Factors | |||
The most important risk factor for ovarian cancer is a family history of a first-degree relative (e.g., mother, daughter, or sister) with the disease. Approximately 20% of ovarian cancers are familial, and although most of these are linked to mutations in the BRCA1 or BRCA2 genes, several other genes have been implicated in familial ovarian cancers.[6,7] The highest risk appears in women who have two or more first-degree relatives with ovarian cancer.[8] The risk is somewhat less for women who have one first-degree and one second-degree relative (grandmother or aunt) with ovarian cancer. | |||
In most families affected with the breast and ovarian cancer syndrome or site-specific ovarian cancer, genetic linkage has been found to the BRCA1 locus on chromosome 17q21.[9-11] BRCA2, also responsible for some instances of inherited ovarian and breast cancer, has been mapped by genetic linkage to chromosome 13q12.[12] The lifetime risk for developing ovarian cancer in patients harboring germline mutations in BRCA1 is substantially increased over that of the general population.[13,14] Two retrospective studies of patients with germline mutations in BRCA1 suggest that these women have improved survival compared with BRCA1 mutation-negative women.[15,16][Level of evidence: 3iiiA] Most women with a BRCA1 mutation probably have family members with a history of ovarian and/or breast cancer; therefore, these women may have been more vigilant and inclined to participate in cancer screening programs that may have led to earlier detection. | |||
For women at increased risk, prophylactic oophorectomy may be considered after age 35 years if childbearing is complete. In a family-based study among women with BRCA1 or BRCA2 mutations, of the 259 women who had undergone bilateral prophylactic oophorectomy, 2 of them (0.8%) developed subsequent papillary serous peritoneal carcinoma, and 6 of them (2.8%) had stage I ovarian cancer at the time of surgery. Of the 292 matched controls, 20% who did not have prophylactic surgery developed ovarian cancer. Prophylactic surgery was associated with a higher-than-90% reduction in the risk of ovarian cancer (relative risk [RR], 0.04; 95% confidence interval [CI], 0.01–0.16), with an average follow-up of 9 years;[17] however, family-based studies may be associated with biases resulting from case selection and other factors that may influence the estimate of benefit.[18] (Refer to the Description of the Evidence section in the PDQ summary on Ovarian, Fallopian Tube, and Primary Peritoneal Cancer Prevention for more information.) | |||
After a prophylactic oophorectomy, a small percentage of women may develop a primary peritoneal carcinoma that is similar in appearance to ovarian cancer.[19] | |||
== References == | == References == | ||
Revision as of 18:42, 8 December 2015
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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
Overview
The risk of developing ovarian cancer appears to be affected by several factors; in fact, early age at first pregnancy, older ages of final pregnancy, and the use of low dose hormonal contraception have been associated with a lower incidence of ovarian cancer. There is good evidence that in some women genetic factors are important.
Risk Factors
The more children a woman has, the lower her risk of ovarian cancer. Early age at first pregnancy, older ages of final pregnancy and the use of low dose hormonal contraception have also been shown to have a protective effect. Ovarian cancer is reduced in women after tubal ligation.
The link to the use of fertility medication, such as Clomiphene citrate, has been controversial. An analysis in 1991 raised the possibility that use of drugs may increase the risk of ovarian cancer. Several cohort studies and case-control studies have been conducted since then without providing conclusive evidence for such a link. [1] It will remain a complex topic to study as the infertile population differs in parity from the "normal" population.
There is good evidence that in some women genetic factors are important. Carriers of certain mutations of the BRCA1 or the BRCA2 gene and certain populations (e.g. Ashkenazi Jewish women) are at a higher risk of both breast cancer and ovarian cancer, often at an earlier age than the general population. Patients with a personal history of breast cancer or a family history of breast and/or ovarian cancer, especially if at a young age, may have an elevated risk. A strong family history of uterine cancer, colon cancer, or other gastrointestinal cancers may indicate the presence of a syndrome known as hereditary nonpolyposis colorectal cancer (HNPCC, also known as Lynch II syndrome), which confers a higher risk for developing ovarian cancer. Patients with strong genetic risk for ovarian cancer may consider the use of prophylactic i.e. preventative oophorectomy after completion of child-bearing.
A Swedish study, which followed more than 61,000 women for 13 years, has found a significant link between milk consumption and ovarian cancer. According to the BBC, "[Researchers] found that milk had the strongest link with ovarian cancer - those women who drank two or more glasses a day were at double the risk of those who did not consume it at all, or only in small amounts." [2] Recent studies have shown that women in sunnier countries have a lower rate of ovarian cancer, which may have some kind of connection with exposure to Vitamin D.
Other factors that have been investigated, such as talc use, asbestos exposure, high dietary fat content, and childhood mumps infection, are controversial and have not been definitively proven.
"Associations were also found between alcohol consumption and cancers of the ovary and prostate, but only for 50 g and 100 g a day."[3] Risk Factors
The most important risk factor for ovarian cancer is a family history of a first-degree relative (e.g., mother, daughter, or sister) with the disease. Approximately 20% of ovarian cancers are familial, and although most of these are linked to mutations in the BRCA1 or BRCA2 genes, several other genes have been implicated in familial ovarian cancers.[6,7] The highest risk appears in women who have two or more first-degree relatives with ovarian cancer.[8] The risk is somewhat less for women who have one first-degree and one second-degree relative (grandmother or aunt) with ovarian cancer.
In most families affected with the breast and ovarian cancer syndrome or site-specific ovarian cancer, genetic linkage has been found to the BRCA1 locus on chromosome 17q21.[9-11] BRCA2, also responsible for some instances of inherited ovarian and breast cancer, has been mapped by genetic linkage to chromosome 13q12.[12] The lifetime risk for developing ovarian cancer in patients harboring germline mutations in BRCA1 is substantially increased over that of the general population.[13,14] Two retrospective studies of patients with germline mutations in BRCA1 suggest that these women have improved survival compared with BRCA1 mutation-negative women.[15,16][Level of evidence: 3iiiA] Most women with a BRCA1 mutation probably have family members with a history of ovarian and/or breast cancer; therefore, these women may have been more vigilant and inclined to participate in cancer screening programs that may have led to earlier detection.
For women at increased risk, prophylactic oophorectomy may be considered after age 35 years if childbearing is complete. In a family-based study among women with BRCA1 or BRCA2 mutations, of the 259 women who had undergone bilateral prophylactic oophorectomy, 2 of them (0.8%) developed subsequent papillary serous peritoneal carcinoma, and 6 of them (2.8%) had stage I ovarian cancer at the time of surgery. Of the 292 matched controls, 20% who did not have prophylactic surgery developed ovarian cancer. Prophylactic surgery was associated with a higher-than-90% reduction in the risk of ovarian cancer (relative risk [RR], 0.04; 95% confidence interval [CI], 0.01–0.16), with an average follow-up of 9 years;[17] however, family-based studies may be associated with biases resulting from case selection and other factors that may influence the estimate of benefit.[18] (Refer to the Description of the Evidence section in the PDQ summary on Ovarian, Fallopian Tube, and Primary Peritoneal Cancer Prevention for more information.)
After a prophylactic oophorectomy, a small percentage of women may develop a primary peritoneal carcinoma that is similar in appearance to ovarian cancer.[19]
References
- ↑ Brinton LA, Moghissi KS, Scoccia B, Westhoff CL, Lamb EJ (2005). "Ovulation induction and cancer risk". Fertil. Steril. 83 (2): 261–74, quiz 525-6. doi:10.1016/j.fertnstert.2004.09.016. PMID 15705362.
- ↑ BBC News Milk link to ovarian cancer risk 29 November 2004
- ↑ Alcohol consumption and cancer risk