Catalysts towards cancer risk management action: A longitudinal study of reproductive-aged women with BRCA1/2 mutations

ABSTRACT

Deleterious mutations in BRCA1 or BRCA2 genes increase a woman's lifetime risk of breast and ovarian cancer. Risk management guidelines endorse early detection and prevention behaviors. Despite expressed intent, uptake of these measures remains low. This longitudinal, qualitative study integrated retrospective and prospective data to distinguish factors shaping intent to act from those that are catalysts to taking action to reduce cancer risk. Twelve BRCA1/2 mutation-positive women participating in the National Cancer Institute's Breast Imaging Study aged 18–35 completed two semi-structured interviews three years apart. Researchers completed focused coding to identify points of behavioral intent and action and contextual factors acting as catalysts upon participant narratives. All women shared only two action steps: seeking information about cancer risk and completing genetic testing. The constellation of action steps created a unique action trajectory that was defined, with precise ideas about risk perception and clear behavioral response, or iterative, in which unanticipated life events shifted the speed, accessibility, or order in which risk management and family planning goals were prioritized, planned, or executed. Factors shifting action steps included salient, unanticipated life events, such as infertility, insurance/financial constraints, birth of the last child, or a relative's cancer diagnosis. Focus on cancer morbidity may obfuscate how women prioritize actions, and ignore varied pragmatic, relational, and social factors affecting how intended actions are completed, particularly during the reproductive years. We recommend providers update patients' risk management plans at each visit to assess readiness for next steps and reduce reluctance to discuss, or guilt associated with, change.     

Risk of cancer in BRCA1 and BRCA2 mutation-positive and -negative breast cancer families (Finland)

Objectives: To compare the risk of cancer between BRCA1 or BRCA2 mutation-positive and -negative families. Methods: We assessed standardized incidence ratios (SIR) in 107 Finnish breast cancer families (12 BRCA1, 11 BRCA2, 84 non-BRCA1/2) with confirmed genealogy. The observed numbers of cancer cases were compared to the expected ones; both numbers were based on the population-based Finnish Cancer Registry. Results: Risk of ovarian cancer for first-degree relatives was high in BRCA1 (SIR 29, 95% confidence interval 9.4–68) and in BRCA2 families (SIR 18, 8.3–35), but not increased for non-BRCA1/2 families (SIR 1.0, 0.2–2.9). The SIR for subsequent ovarian cancer among breast cancer patients was 61 (20–142), 38 (11–98), and 0 (0–4.2), respectively. The risk of subsequent new breast cancer among breast cancer patients was equally high in BRCA1 families (SIR 11, 3.6–26) and in BRCA2 families (SIR 10, 3.3–24) and somewhat lower in mutation-negative families (SIR 3.7, 2.1–6.1). The risk of breast cancer among relatives was markedly increased in all three groups. The only elevated SIR, besides breast and ovarian, was that for prostate cancer in BRCA2 families (SIR 4.9, 1.8–11). Conclusions: The excess risk of breast cancer in non-BRCA1/2 families suggests the existence of another predisposition gene which seems not to be linked with increased risk of ovarian cancer.     

Diabetes and breast cancer among women with BRCA1 and BRCA2 mutations

BACKGROUND:

Hyperinsulinemia and the metabolic syndrome are both risk factors for breast cancer. It is not clear if diabetes is associated with the risk of breast cancer in women with a BRCA1 or BRCA2 mutation.

METHODS:

The authors reviewed the medical histories of 6052 women with a BRCA1 or BRCA2 mutation, half of whom had been diagnosed with breast cancer. They estimated the odds ratio for breast cancer, given a self‐report of diabetes. They then estimated the hazard ratio for a new diagnosis of diabetes associated with a history of breast cancer.

RESULTS:

There was no excess of diabetes in the period before the diagnosis of breast cancer, compared with controls with no diagnosis of breast cancer. The risk of diabetes was doubled among BRCA carriers in the 15‐year period after the diagnosis of breast cancer (relative risk, 2.0; 95% confidence interval [CI], 1.4‐2.8; P = .0001), compared with carriers without cancer. The risk was particularly high for women with a body mass index (BMI) >25.0 kg/m² (odds ratio, 5.8; 95% CI, 4.0‐8.6; P = .0001).

CONCLUSIONS:

After a diagnosis of breast cancer, women with a BRCA1 or BRCA2 mutation face a 2‐fold increase in the risk of diabetes, which is exacerbated by a high BMI. Cancer 2011. © 2010 American Cancer Society.     

家族性乳腺癌患者及家系成员乳腺癌易感基因携带情况调查

目的 乳腺癌易感基因1(breast cancer susceptibility gene 1,BRCA1)和BRCA2基因已经证实与家族性乳腺癌密切相关.本研究旨在分析中国汉族家族性乳腺癌患者及家系成员BRCA1和BRCA2突变特征及携带情况.方法 收集2013 12-02-2015-06-08军事医学科学院附属医院确诊的中国汉族家族性乳腺癌患者55例及家系成员48名,共计103例样本.柚取外周静脉血提取DNA,应用聚合酶链反应(polymerase chain reaction,PCR) DNA直接测序方法检测BRCA1和BRCA2基因全编码外显子序列.结果 55例家族性乳腺癌患者中发现5个BRCA基因致病性突变位点,1个突变位点乳腺癌信息库中见报道(BRCA1:4730insG),4个为新发现突变位点(BRCA1:1937insC,4538insAG;BRCA2:1382delA,2820delA).家族性乳腺癌患者BRCA1/2突变率为9.09％(BRCA1,5.45％;BRCA2,3.64％),其中三阴性乳腺癌患者突变率为22.22％(x2 =1.99,P=0.20),早发性乳腺癌患者(≤35岁)突变率为20.00％,x2=0.79,P=0.39.48例家系成员检测到3个新发现突变位点(BRCA1:1370insA,3459insA;BRCA2:6502insT),总突变率为6.25％.结论 中国汉族家族性乳腺癌患者BRCA基因突变率显著低于国外,应重点关注有家族史的三阴性乳腺癌患者和早发性乳腺癌患者;家系成员中发现BRCA基因致病性突变,家系成员突变率和发病风险有待进一步研究,应引起重视.     

Effect of pregnancy as a risk factor for breast cancer in BRCA1/BRCA2 mutation carriers

Early age at first birth and multiparity have been associated with a decrease in the risk of breast cancer in women in the general population. We examined whether this relationship is also present in women at high risk of breast cancer due to the presence of a mutation in either of the 2 breast cancer susceptibility genes, BRCA1 or BRCA2. We performed a matched case-control study of 1,260 pairs of women with known BRCA1 or BRCA2 mutations, recruited from North America, Europe and Israel. Women who had been diagnosed with breast cancer were matched with unaffected control subjects for year of birth, country of residence, and mutation (BRCA1 or BRCA2). Study subjects completed a questionnaire detailing their reproductive histories. Odds ratios (ORs) and 95% confidence intervals (CIs) were derived by conditional logistic regression. Among BRCA1 carriers, parity per se was not associated with the risk of breast cancer (OR for parous vs. nulliparous = 0.94; 95% CI = 0.75-1.19; p = 0.62). However, women with a BRCA1 mutation and 4 or more children had a 38% decrease in breast cancer risk compared to nulliparous women (OR = 0.62; 95% CI = 0.41-0.94). In contrast, among BRCA2 carriers, increasing parity was associated with an increased risk of breast cancer; women with 2 or more children were at approximately 1.5 times the risk of breast cancer as nulliparous women (OR = 1.53; 95% CI = 1.01-2.32; p = 0.05). Among women with BRCA2 mutations and who were younger than age 50, the (adjusted) risk of breast cancer increased by 17% with each additional birth (OR = 1.17; 95% CI = 1.01-1.36; p = 0.03). There was no significant increase in the risk of breast cancer among BRCA2 carriers older than 50 (OR for each additional birth = 0.97; 95% CI = 0.58-1.53; p = 0.92). In the 2-year period following a birth, the risk of breast cancer in a BRCA2 carrier was increased by 70% compared to nulliparous controls (OR = 1.70; 95% CI = 0.97-3.0). There was a much smaller increase in breast cancer risk among BRCA2 carriers whose last birth was 5 or more years in the past (OR = 1.24; 95% CI = 0.79-1.95). A modest reduction in risk of breast cancer was observed among BRCA1 carriers with 4 or more births. Among BRCA2 carriers, increasing parity was associated with a significant increase in the risk of breast cancer before age 50 and this increase was greatest in the 2-year period following a pregnancy.     

Optimal age to start preventive measures in women with BRCA1/2 mutations or high familial breast cancer risk

Women from high‐risk families consider preventive measures for breast cancer including screening. Guidelines on screening differ considerably regarding starting age. We investigated whether age at diagnosis in affected relatives is predictive for age at diagnosis. We analyzed the age of breast cancer detection of 1,304 first‐ and second‐degree relatives of 314 BRCA1, 164 BRCA2 and 244 high‐risk participants of the Dutch MRI‐SCreening study. The within‐ and between‐family variance in the relative's age at diagnosis was analyzed with a random effect linear regression model. We compared the starting age of screening based on risk‐group (25 years for BRCA1, 30 years for BRCA2 and 35 years for familial risk), on family history, and on the model, which combines both. The findings were validated in 63 families from the UK‐MARIBS study. Mean age at diagnosis in the relatives varied between families; 95% range of mean family ages was 35–55 in BRCA1‐, 41–57 in BRCA2‐ and 44–60 in high‐risk families. In all, 14% of the variance in age at diagnosis, in BRCA1 even 23%, was explained by family history, 7% by risk group. Determining start of screening based on the model and on risk‐group gave similar results in terms of cancers missed and years of screening. The approach based on familial history only, missed more cancers and required more screening years in both the Dutch and the United Kingdom data sets. Age at breast cancer diagnosis is partly dependent on family history which may assist planning starting age for preventive measures.     

The risk of primary and contralateral breast cancer after ovarian cancer in BRCA1/BRCA2 mutation carriers

BACKGROUND:

The objective of this study was to assess the incidence of primary breast cancer (PBC) and contralateral breast cancer (CBC) in patients who had BRCA1/BRCA2‐associated epithelial ovarian cancer (OC).

METHODS:

From the database of the Rotterdam Family Cancer Clinic, patients who had BRCA‐associated OC without a history of unilateral breast cancer (BC) (at risk of PBC; n = 79) or with a history of unilateral BC (at risk of CBC; n = 37) were selected. The control groups consisted of unaffected BRCA mutation carriers (n = 351) or mutation carriers who had a previous unilateral BC (n = 294), respectively. The risks of PBC and CBC were calculated using the Kaplan‐Meier survival method with death considered as a competing risk event.

RESULTS:

Women with BRCA‐associated OC had lower 2‐year, 5‐year, and 10‐year risks of PBC (3%, 6%, and 11%, respectively) compared with unaffected mutation carriers (6%, 16%, and 28%, respectively; P = .03), although they had a considerably higher mortality rate at similar time points (13%, 33%, and 61%, respectively, vs 1%, 2%, and 2%, respectively; P < .001). In BRCA mutation carriers with a previous unilateral BC, the 2‐year, 5‐year, and 10‐year risks of CBC were nonsignificantly lower in patients with OC than in those without OC (0%, 7%, and 7%, respectively, vs 6%, 16%, and 34%, respectively; P = .06), whereas the mortality rate was higher in patients with OC (19%, 34%, and 55%, respectively, vs 4%, 11%, and 21%, respectively; P < .001).

CONCLUSIONS:

Patients with BRCA‐associated OC had a lower risk of developing a subsequent PBC or CBC than mutation carriers without OC, whereas the risk of dying from OC was greater than the risk of developing BC. These data may facilitate more tailored counseling for this patient subgroup, although confirmative studies are warranted. Cancer 2013. © 2012 American Cancer Society.     

Coffee consumption and breast cancer risk among BRCA1 and BRCA2 mutation carriers

Although there are several plausible biologic mechanisms whereby coffee consumption might influence the risk of breast cancer, epidemiologic evidence is limited. We assessed the association between coffee consumption and breast cancer risk among high-risk women who carry BRCA mutations. We performed a matched case-control analysis on 1,690 women with a BRCA1 or BRCA2 mutation from 40 centers in 4 countries. Average lifetime coffee consumption was estimated via a self-administered questionnaire. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using conditional logistic regression. After adjustment for potential confounders, the ORs for breast cancer in BRCA carriers who habitually drank 0, 1-3, 4-5 and 6 or more cups of coffee were 1.00, 0.90 (95% CI 0.72-1.12), 0.75 (95% CI 0.47-1.19) and 0.31 (95% CI 0.13-0.71; p-trend = 0.02). The effect was limited to the consumption of caffeinated coffee. These results suggest that among women with BRCA gene mutation, coffee consumption is unlikely to be harmful and that high levels of consumption may in fact be related to reduced breast cancer risk.     

Predictors of contralateral breast cancer in BRCA1 and BRCA2 mutation carriers

Purpose:

The objective of this study was to estimate the risk of contralateral breast cancer in BRCA1 and BRCA2 carriers; and measure the extent to which host, family history, and cancer treatment-related factors modify the risk.

Patients and methods:

Patients were 810 women, with stage I or II breast cancer, for whom a BRCA1 or BRCA2 mutation had been identified in the family. Patients were followed from the initial diagnosis of cancer until contralateral mastectomy, contralateral breast cancer, death, or last follow-up.

Results:

Overall, 149 subjects (18.4%) developed a contralateral breast cancer. The 15-year actuarial risk of contralateral breast cancer was 36.1% for women with a BRCA1 mutation and was 28.5% for women with a BRCA2 mutation. Women younger than 50 years of age at the time of breast cancer diagnosis were significantly more likely to develop a contralateral breast cancer at 15 years, compared with those older than 50 years (37.6 vs 16.8% P=0.003). Women aged <50 years with two or more first-degree relatives with early-onset breast cancer were at high risk of contralateral breast cancer, compared with women with fewer, or no first-degree relatives with breast cancer (50 vs 36% P=0.005). The risk of contralateral breast cancer was reduced with oophorectomy (RR 0.47; 95% CI 0.30–0.76; P=0.002).

Conclusion:

The risk of contralateral breast cancer risk in BRCA mutation carriers declines with the age of diagnosis and increases with the number of first-degree relatives affected with breast cancer. Oophorectomy reduces the risk of contralateral breast cancer in young women with a BRCA mutation.     

Contralateral breast cancer risk in BRCA1 and BRCA2 mutation carriers in a large cohort of unselected Chinese breast cancer patients

To estimate the cumulative risk of contralateral breast cancer (CBC) in BRCA1/2 carriers in a large cohort of unselected Chinese breast cancer patients. Our study comprised 9,401 unselected Chinese breast cancer patients and BRCA1/2 germline mutations were determined in all patients. After a median follow-up of 5.7 years, 181 patients developed CBC in this cohort. Compared to noncarriers, BRCA1 and BRCA2 carriers had a 4.52-fold (95% CI, 2.63–7.76) and 5.54-fold (95% CI, 3.51–8.74) increased risk of CBC, respectively. The 10-year cumulative risk of CBC was 15.5% (95% CI, 9.9–24.2) for BRCA1 carriers, 17.5% (95% CI, 10.9–28.0) for BRCA2 carriers and 3.2% (95% CI, 2.5–4.1) for noncarriers. Younger age at first breast cancer diagnosis was significantly associated with an increased 10-year risk of CBC for BRCA1 carriers (≤40 years vs. >40 years: 21.5% vs. 11.9%, unadjusted hazard ratio [HR] = 2.51, 95% CI, 1.03–6.15, p = 0.044), but not for BRCA2 carriers and noncarriers. The 10-year cumulative CBC risk was significantly higher in both BRCA1 and BRCA2 carriers who had a family history of breast cancer than in those who did not (BRCA1: 27.5% vs. 9.4%, adjusted HR = 2.64, 95% CI, 1.01–6.97, p = 0.049; BRCA2: 27.1% vs. 12.8%, adjusted HR = 2.29, 95% CI, 1.04–5.06, p = 0.040). In conclusion, the risk of CBC was a substantial high in BRCA1/2 carriers in unselected Chinese breast cancer patients, and CBC risk is much more remarkable in both BRCA1 and BRCA2 carriers who had a family history of breast cancer. Younger age at first breast cancer diagnosis also enhanced CBC risk in BRCA1 carriers.     

Estimates of the likely prophylactic effect of tamoxifen in women with high risk BRCA1 and BRCA2 mutations

The development of breast cancer control strategies in women at high genetic risk of breast cancer is an important issue. The likely benefit of chemopreventive approaches is of particular interest. Tamoxifen tends to be more effective in both prevention and treatment of oestrogen receptor positive tumours than oestrogen receptor negative. In this study, we combine the oestrogen-receptor specific effects of tamoxifen from randomized preventive or therapeutic trials with the oestrogen receptor status of tumours in BRCA1 and BRCA2 mutation positive women from published tumour surveys to obtain estimates of the likely effect of tamoxifen administration in mutation carriers. We used a simple two-stage procedure to estimate the benefit as a weighted average of the effect on oestrogen receptor positive tumours and oestrogen receptor negative, and using a more complex hierarchical modelling approach. Using the simple procedure and deriving the estimates of benefit from both primary prevention and therapeutic trials, we obtain an estimated reduction in risk of breast cancer from administration of tamoxifen in BRCA1 mutation positive women of 13% (RR=0.87, 95% CI 0.68--1.11). The corresponding estimated reduction in BRCA2 mutation positive women was 27% (RR=0.73, 95% CI 0.59--0.90). Using the more complex models gave essentially the same results. Using only the primary prevention trials gave smaller estimates of benefit in BRCA1 carriers but larger estimates in BRCA2, in both cases with wider confidence intervals. The benefit of prophylactic use of tamoxifen in BRCA1 mutation carriers is likely to be modest, and the effect in BRCA2 mutation carriers somewhat greater.     

The risk of breast cancer in women with a BRCA1 mutation from North America and Poland

Women with a BRCA1 mutation face a high lifetime risk of breast cancer. It is unknown to what extent environmental factors modify the inherent genetic risk. If women from different countries, but with similar mutations, experience different levels of cancer risk, nongenetic risk modifiers are likely to be present. Study subjects were a cohort of 1477 women with a BRCA1 mutation, from Canada (n = 358), the United States (n = 256) and Poland (n = 863). The women were followed for a mean of 4.3 years and 130 incident cases of breast cancer were recorded. Annual cancer incidence rates were calculated, and based on these, penetrance curves were constructed for women from North America and Poland. In a Cox proportional hazards model, residence in Poland, versus North America, was associated with an adjusted hazard ratio of 0.54 (95% CI 0.34-0.86; p = 0.01). The risk of breast cancer to age 70 was estimated to be 49% for women from Poland and 72% for women from North America. Among women with BRCA1 mutations, the risk of breast cancer in women who reside in Poland is less than that of women who reside in North America. The reasons for the difference are unknown, but this observation suggests that environmental factors or genetic modifiers are important in determining risk.     

BRCA1/2突变的中国健康女性乳腺预防性切除及Ⅰ期重建的临床实践

目的:探讨对携带BRCA1/2突变的中国健康女性实施乳腺预防性切除及I期重建的可行性。方法:选择2018年1月至2019年2月3例于北京大学国际医院就诊的携带BRCA1/2突变的中国健康女性,其中2例携带BRCA1突变、1例携带BRCA2突变,均有乳腺癌家族史,年龄为34~36岁,实施预防性保留乳头-乳晕的双侧乳腺切除和Ⅰ期假体重建术。结果:3例患者术后无并发症发生,术后中位随访时间为18个月,均无乳腺癌发生,对重建乳房外形满意,且焦虑和恐惧情绪显著下降,取得良好的疗效。结论:对携带BRCA1/2突变且有乳腺癌家族史的中国健康女性,在严格筛选的基础上,可慎重开展乳腺预防性切除及Ⅰ期重建术。     

Breast conservation in BRCA1 or BRCA2 mutation carriers with early stage breast cancer

The role of breast conservation therapy (limited surgery and irradiation of the breast with/without axilla) in the approximately 5% of breast cancer patients who harbour a germline mutation in BRCA1 or BRCA2, is a largely unexplored area and is seen by some as controversial. The relatively high cumulative risk of second primary cancers in such patients and concern about a possible decreased ability of mutation carriers to repair DNA damage caused by radiation has fuelled this controversy. Published studies of breast conservation therapy in carriers of a mutation in BRCA1 or BRCA2 are reviewed, with particular attention to their methodology. These studies have not demonstrated any increase in radiation sensitivity of normal tissues in mutation carriers, either in terms of increased early or late toxicity or tumourigenesis. Likewise, tumour sensitivity to radiotherapy, which might be expected based on the known functions of the BRCA1 and BRCA2 genes, has not been documented to date in mutation carriers. Further, methodologically rigorous studies of large numbers of breast cancer patients who carry a mutation in BRCA1 or BRCA2 are required to fully elucidate these issues.     

Sporadic breast cancer in young women: prevalence of loss of heterozygosity at p53, BRCA1 and BRCA2

Previous studies have shown that breast cancers have more aggressive pathologic features in young women. In order to examine genetic alterations associated with early-onset breast cancer, 31 patients with no known family history, aged 26-35 years at diagnosis, were examined for loss of heterozygosity (LOH) at 3 key chromosomal intervals: 17p (p53), 17q 21 (BRCA1) and 13q12-13 (BRCA2) using polymerase chain reaction analysis of polymorphic microsatellite markers. These were compared with 31 patients aged 55-72 years that were matched for size, type and grade. All young breast cancer cases exhibited LOH for at least 1 marker and 20 cases (64.5%) exhibited LOH at 1 or more markers from each interval. The frequency of LOH detected for each of the markers was as follows 17p: p534N (33.3%), D17S796 (36.7%), D17S799 (63.3%) and D17S513 (59.3%); 17q: D17S855 (64.5%), THRA1 (46.7%) and D17S579 (33.3%); and 13q: D13S260 (74.2%), D13S171 (47.6%) and D13S267 (40.0%). These frequencies are higher than those observed at the 3 markers studied in the matched postmenopausal patients: D17S799 (41.4%), D17S855 (35.5%), D13S260 (30.0%). These differences in frequency of LOH were statistically significant for the D17S855 and D13S260 markers (p < 0.025 and p < 0.001 respectively). Although there were more grade III carcinomas (21 of 31 cases), there was no correlation between number of alterations and high grade in younger cases. These data suggest that LOH at these regions could be related to early-onset sporadic breast cancer.     

BRCA1 and BRCA2 mutations among breast cancer patients from the Philippines

Age-adjusted incidence rates of breast cancer vary more than 10-fold worldwide, with the highest rates reported in North America and Europe. The highest breast cancer incidence rates in Southeast Asia have been reported for the Manila Cancer Registry in the Philippines, with an age-standardized rate of 47.7 per 100,000 per year. The possible contribution of hereditary factors to these elevated rates has not been investigated. We conducted a case-control study of 294 unselected incident breast cancer cases and 346 female controls from Manila, Philippines. Cases and controls were selected from women below the age of 65 undergoing evaluation at the PGH in Manila because of a suspicious breast mass. Molecular analysis identified 12 BRCA2 mutations and 3 BRCA1 mutations. We estimate the prevalence of BRCA mutations among unselected breast cancer cases in the Philippines to be 5.1% (95% CI: 2.6-7.6%), with a prevalence of 4.1% (95% CI: 1.8-6.4%) for BRCA2 mutations alone. The BRCA2 4265delCT and 4859delA mutations were found in 2 and 4 unrelated cases, respectively; haplotype analysis confirmed that these, and the BRCA1 5454delC mutation, are founder mutations. BRCA2 mutations were also found in 2 of 346 controls (0.6%; 95% CI: 0.2-1.4%). Compared with non-carrier cases, the cumulative risk of breast cancer for first-degree relatives of mutation carriers was 24.3% to age 50, compared with <4% for first-degree relatives of non-carrier cases (RR = 6.6; 95% CI: 2.6-17.2; p= 7.5 x 10(-6)). Our data suggest that penetrance of BRCA mutations is not reduced in the Philippines. Germline mutations in the BRCA2 gene contribute more than mutations BRCA1 to breast cancer in the Philippines, due in large part to the presence of 2 common founder mutations.     

Survival of breast cancer patients in BRCA1, BRCA2, and non-BRCA1/2 breast cancer families: a relative survival analysis from Finland.

Reports on the prognosis of familial breast cancer patients have been contradictory. True differences in survival, if they exist, would have important implications for genetic counselling and in treatment of hereditary breast cancer. We assessed the survival rates of 359 familial breast cancer patients (32 patients from BRCA1-positive families, 43 patients from BRCA2-positive families and 284 patients from BRCA1/2-negative breast cancer families) and compared them with those of all other breast cancer patients diagnosed in Finland from 1953 to 1995 (n = 59,517). Cumulative relative survival rates (RSR) were calculated by dividing the observed survival rates by the expected ones. The expected survival rates were derived from the sex, age and calendar year specific life-tables of the general population in Finland. Regression model was used to calculate relative excess risk of death (RR) and to adjust for confounding factors. The overall 5-year RSR of the patients in the BRCA1 families, BRCA2 families, non-BRCA1/2 families and among sporadic cases was 67%, 77%, 86% and 78%, respectively. However, we found no significant differences in the RR adjusted for age, stage and year of diagnosis between the different familial patient groups or the general breast cancer population. In the BRCA1 families the RR tended to be higher [RR 1.30, 95% confidence interval (CI) 0.63--2.70] and in the BRCA2 families lower (RR 0.78, 95% CI 0.39--1.57) than among the general breast cancer patient population. The RR among patients in the non-BRCA1/2 families did not differ from that of the general patient population.     

Collaboration of breast cancer clinic and genetic counseling division for BRCA1 and BRCA2 mutation family in Japan

BACKGROUND: BRCA1 and BRCA2 mutations cause high breast cancer incidence rates as high as 80% Although prophylactic therapy is still controversial, several prophylactic therapies have been proposed and tried for BRCA1 and BRCA2 mutation carriers. Prophylactic surgery, chemo-prevention and precise screening have been proposed as prophylactic therapy. All BRCA1 and BRCA2 mutation carriers need knowledge about their disease and the countermeasures that are used to protect against onset of disease. Counseling plays an important role in this regard for people with genetic diseases. Therefore, collaboration between breast cancer clinics and genetic counseling services is the most important issue in clinical practice. Our group consists of three national universities and a general hospital. In this article we describe our trial to construct a clinical system against hereditary breast cancer as an interim report for the Japanese Ministry of Health, Labour and Welfare. PATIENTS AND METHODS: Twenty familial breast cancer patients were registered in this study. The whole sequence of BRCA1 and BRCA2 were analyzed. If pathological mutations were detected, their first degree families were introduced to the counseling division at each institute when candidates visited counseling divisions. RESULTS AND DISCUSSION: Four cases of a deleterious mutation in BRCA1 or BRCA2 were detected among 20 cases. Their first degree relatives are now under consideration for visiting counseling divisions. The clinical system described in this study should play a role to protect BRCA1 or BRCA2 mutation carriers in Japan.