Risk factors and risk reduction of breast and ovarian cancer

Purpose of review: Breast and ovarian cancer remain a significant burden for women living in the Western world. This paper reviews the risk factors and current strategies to prevent these diseases. Recent findings: Established factors associated with the risk of breast cancer include family history, reproductive factors and lactation, as well as age at menarche and menopause. Hormone replacement therapy increases the risk, whereas oral contraceptives probably confer no increased risk. Alcohol moderately increases the risk, whereas a diet rich in folate and carotenoids might be protective. The role of other dietary factors, smoking and physical exercise remain unclear. Important risk factors for ovarian cancer are reproductive factors and possibly the long-term use of hormone replacement therapy. The risk is decreased by oral contraceptives. In carriers of a BRCA1 or BRCA2 gene mutation, prophylactic surgery can significantly reduce the risk of breast as well as ovarian cancer. Tamoxifen may be considered as a chemopreventive agent in women with a high risk of breast cancer, including carriers of a BRCA2 mutation, but is probably not effective in BRCA1 carriers. Summary: During the period of this review, the importance of several known risk factors was confirmed, whereas the effects of other factors became more clear. Chemoprevention and prophylactic surgery have emerged as preventative options that can reduce the risk of breast and ovarian cancer

The CHEK2 1100delC mutation identifies families with a hereditary breast and colorectal cancer phenotype

Because of genetic heterogeneity, the identification of breast cancer-susceptibility genes has proven to be exceedingly difficult. Here, we define a new subset of families with breast cancer characterized by the presence of colorectal cancer cases. The 1100delC variant of the cell cycle checkpoint kinase CHEK2 gene was present in 18% of 55 families with hereditary breast and colorectal cancer (HBCC) as compared with 4% of 380 families with non-HBCC (P<.001), thus providing genetic evidence for the HBCC phenotype. The CHEK2 1100delC mutation was, however, not the major predisposing factor for the HBCC phenotype but appeared to act in synergy with another, as-yet-unknown susceptibility gene(s). The unequivocal definition of the HBCC phenotype opens new avenues to search for thi

Efficacy of MRI and mammography for breast-cancer screening in women with a familial or genetic predisposition.

Contains fulltext : 58587.pdf (publisher's version ) (Open Access)BACKGROUND: The value of regular surveillance for breast cancer in women with a genetic or familial predisposition to breast cancer is currently unproven. We compared the efficacy of magnetic resonance imaging (MRI) with that of mammography for screening in this group of high-risk women. METHODS: Women who had a cumulative lifetime risk of breast cancer of 15 percent or more were screened every six months with a clinical breast examination and once a year by mammography and MRI, with independent readings. The characteristics of the cancers that were detected were compared with the characteristics of those in two different age-matched control groups. RESULTS: We screened 1909 eligible women, including 358 carriers of germ-line mutations. Within a median follow-up period of 2.9 years, 51 tumors (44 invasive cancers, 6 ductal carcinomas in situ, and 1 lymphoma) and 1 lobular carcinoma in situ were detected. The sensitivity of clinical breast examination, mammography, and MRI for detecting invasive breast cancer was 17.9 percent, 33.3 percent, and 79.5 percent, respectively, and the specificity was 98.1 percent, 95.0 percent, and 89.8 percent, respectively. The overall discriminating capacity of MRI was significantly better than that of mammography (P<0.05). The proportion of invasive tumors that were 10 mm or less in diameter was significantly greater in our surveillance group (43.2 percent) than in either control group (14.0 percent [P<0.001] and 12.5 percent [P=0.04], respectively). The combined incidence of positive axillary nodes and micrometastases in invasive cancers in our study was 21.4 percent, as compared with 52.4 percent (P<0.001) and 56.4 percent (P=0.001) in the two control groups. CONCLUSIONS: MRI appears to be more sensitive than mammography in detecting tumors in women with an inherited susceptibility to breast cancer

Hereditary breast cancer growth rates and its impact on screening policy

Contains fulltext : 47763.pdf (publisher's version ) (Closed access)Imaging is often performed yearly for the surveillance of BRCA1/2 mutation carriers and women at high familial breast cancer risk. Growth of cancers in carriers may be faster as these tumours are predominantly high grade. Quantitative data on tumour growth rates in these 2 groups are lacking. Here, we have examined 80 high-risk women under surveillance for tumour size at diagnosis and preceding examinations at mammography and/or MRI. Tumour volume doubling time (DT) was assessed in 30 cancers in BRCA1/2 mutation carriers and 25 non-carriers. Impact of age and menopausal status were also evaluated. Mean DT of all invasive cancers was shorter in carriers (45 days CI: 26-73) than non-carriers (84 days CI: 58-131) (P = 0.048). Mean age at diagnosis was lower in carriers (40 years) than non-carriers (45 years) (P = 0.007). At multivariable analysis only age (P = 0.03), not risk-group (P = 0.26) nor menopause (P = 0.58) correlated significantly with DT. The mean growth rate slowed down to half in each successive 10 years-older group. In conclusion, age at detection indicated the growth rates of hereditary and familial breast cancers. It is recommended that the screening frequency should be adjusted according to a woman's age and a high-sensitive biannual test may be appropriate before the age of 40 years

One year follow-up of women opting for presymptomatic testing for BRCA1 and BRCA2: emotional impact of the test outcome and decisions on risk management (surveillance or prophylactic surgery).

Genetic testing enables women at risk for hereditary breast and/or ovarian cancer to find out whether they have inherited the gene mutation (BRCA1/BRCA2), and if so, to opt for frequent surveillance and/or prophylactic surgery (bilateral mastectomy and/or oophorectomy). Here, a follow-up is described for 63 healthy women at 50% risk of being a BRCA1/BRCA2 mutation carrier who underwent genetic testing. The course of distress and problems regarding body image and sexuality up to 1 year after disclosure of the test-outcome were described separately for mutation carriers undergoing mastectomy (n = 14), for mutation carriers opting for surveillance (n = 12) and for non-mutation carriers (n = 37). Furthermore, we analyzed whether women opting for prophylactic mastectomy differed from those opting for close surveillance with respect to biographical characteristics, experiences with cancer in relatives and personality. Women opting for prophylactic mastectomy had significantly higher distress levels than mutation carriers who opted for surveillance, and the non-mutation carriers. This difference in levels of distress was highest at pre- and post-test and had almost disappeared at 1-year follow-up. Besides, mutation carriers opting for prophylactic mastectomy were more often in their thirties, more often had young children and had a longer awareness of the genetic nature of cancer in the family than those opting for regular surveillance. Adverse effects were observed in women who underwent prophylactic mastectomy (mostly in combination with immediate breast reconstruction) regarding the perception of how their breast region looked like and felt, the intimate relationship and physical wellbeing whereas women opting for prophylactic mastectomy reported more distress than the other women in the study, their distress levels had significantly decreased 6 months or longer after surgery, possibly due to the significant risk reduction of developing breast cancer. This might explain, why most women who underwent prophylactic mastectomy were satisfied with this decision, despite a perceived negative impact on body image, the intimate relationship and physical wellbeing

Ipsilateral breast tumour recurrence in hereditary breast cancer following breast-conserving therapy.

Contains fulltext : 57795.pdf (publisher's version ) (Closed access)The overall rate of an ipsilateral breast tumour recurrence (IBTR) after breast-conserving therapy (BCT) ranges from 1% to 2% per year. Risk factors include young age but data on the impact of BRCA1/2 mutations or a definite positive family history for breast cancer are scarce. We investigated IBTR after BCT in patients with hereditary breast cancer (HBC). Through our family cancer clinic we identified 87 HBC patients, including 26 BRCA1/2 carriers, who underwent BCT between 1980 and 1995 (cases). They were compared to 174 patients with sporadic breast cancer (controls) also treated with BCT, matched for age and year of diagnosis. Median follow up was 6.1 years for the cases and 6.0 years for controls. Patient and tumour characteristics were similar in both groups. An IBTR was observed in 19 (21.8%) hereditary and 21 (12.1%) sporadic patients. In the hereditary patients more recurrences occurred elsewhere in the breast (21% versus 9.5%), suggestive of new primaries. Overall, the actuarial IBTR rate was similar at 2 years, but higher in hereditary as compared to sporadic patients at 5 years (14% versus 7%) and at 10 years (30% versus 16%) (P=0.05). Post-relapse and overall survival was not different between hereditary and sporadic cases. Hereditary breast cancer was therefore associated with a higher frequency of early (2-5 years) and late (>5 years) local recurrences following BCT. These data suggest an indication for long-term follow up in HBC and should be taken into account when additional 'risk-reducing' surgery after primary BCT is eventually considered

Association between the CHEK2*1100delC germ line mutation and estrogen receptor status

Already published data were further analyzed regarding the association between the CHEK2*1100delC germ line mutation and estrogen receptor (ER) status in patients with breast cancer. The CHEK2*1100delC mutation was more prevalent among the patients with a positive ER status (4.2% versus 1.0%). An ER-negative status was beside CHEK2*1100delC mutation and independently associated with an earlier of age onset of breast cancer. There was a trend that an ER-negative status, beside the presence of a CHEK2*1100delC mutation, was associated with a worse disease-free survival. There might be an association between ER status and a CHEK2*1100delC mutation. More studies with larger number of patients are needed to further investigate the relation between CHEK2*1100delC and ER status