First description of a sporadic breast cancer in a woman with BRCA1 germline mutation

We describe the case of a woman carrying a germline pathogenic BRCA1 mutation diagnosed with a breast cancer overexpressing HER2. Clinical presentation of the tumor, HER2-positivity, genomic profile and loss of the mutated BRCA1 allele in tumor evidence that BRCA1 is not inactivated in this breast cancer. It represents the first biological demonstration for the existence of a sporadic HER2-positive breast cancer independent from BRCA loss of function in a woman carrier of a deleterious BRCA1 mutation. In a context where targeted therapies based on BRCA loss of function in the tumor are developed, such case could have direct implications.     

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.     

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.     

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.     

BRCA1 and BRCA2 germline mutation spectrum and frequencies in Belgian breast/ovarian cancer families

Worldwide variation in the distribution of BRCA1 and BRCA2 mutations is well recognised, and for the Belgian population no comprehensive studies about BRCA1/2 mutation spectra or frequencies have been published. We screened the complete coding region of both genes in 451 individuals from 349 Belgian families referred to a family cancer clinic and identified 49 families with a BRCA1 and 26 families with a BRCA2 mutation. Six major recurrent mutations (BRCA1 IVS5+3A>G, 2478-2479insG, E1221X and BRCA2 IVS6+1G>A, 6503-6504delTT, 9132delC) accounted for nearly 60% of all mutations identified. Besides 75 true pathogenic mutations, we identified several variants of unknown clinical significance. In combination with a family history, an early average age of female breast cancer diagnosis (P<0.001), and the presence of a relative with ovarian cancer (P<0.0001) or multiple primary breast cancers (P=0.002), increased the chance for finding a mutation. Male breast cancer was indicative of a BRCA2 mutation segregating in the family (P=0.002). Mutations in the 5'-end of BRCA1 and BRCA2 were associated with a significantly increased risk for ovarian cancer relative to the central portion of the gene. Our study suggests a role for additional breast cancer susceptibility genes in the Belgian population, since mutation detection ratios were low in high-risk breast cancer-only families as compared to breast-ovarian cancer families. Given the large proportion of recurring mutations, molecular testing can now be organised in a more cost-effective way. Our data allow optimisation of genetic counselling and disease prevention in Belgian breast/ovarian cancer families.     

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.     

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.     

BRCA1 and BRCA2 germline mutations in Korean breast cancer patients at high risk of carrying mutations

We analyzed the mutation spectrum of BRCA1 and BRCA2 genes in 354 Korean breast cancer patients. Overall, 40 patients carried 25 distinct BRCA1/2 mutations including 12 novel mutations. Seven district mutations were found in multiple unrelated patients, with the BRCA2 c.7480C>T mutation detected in eight unrelated patients, accounting for 50% of the mutations detected in BRCA2. The large number (25/40, 62.5%) of recurrent mutations suggests the possibility of developing a simple screening test for these mutations. The frequency of mutations was related to the number and kinds of risk factors, varying from 10.4 to 25% in the five major risk factor groups. The frequency of BRCA mutations in patients with two or more risk factors was markedly higher than that in patients with one risk factor.     

BRCA1 andBRCA2 germline mutations in Japanese with hereditary breast cancer families

We examined germline mutations inBRCA1 andBRCA2 in 23 Japanese breast cancer families, using PCR-SSCP analysis. The same nonsense mutation (exon 5, Leu63ter) ofBRCA1 was detected in two different families. Three different mutations resulting in a truncatedBRCA2 protein (exon 9, 20, 24) were detected in three different families, including one male case of breast cancer. One base substitution mutation inBRCA2, A10462G, was detected in the other two families. Although the mean age of onset for breast cancer in families with theBRCA1- mutation was 50 years, the age of onset in families with theBRCA2-mutation was from 28 to 43 years. Among the 23 families examined, two families had members with ovarian cancers, three had members with prostate cancers, and one had a pancreatic cancer. However, none of these families was positive for theBRCA1 orBRCA2 mutation. Histopathologically, we observed a prevalence of histological grade 3 inBRCA2-associated familial breast cancers, because of nuclear atypia, structural atypia and mitotic activity. It is suggested thatBRCA2 may play a more important role thanBRCA1 in Japanese familial breast cancers, and these mutations are related to the aggressive nature and highly proliferative activity of the tumors.     

Oncotype Dx recurrence score among BRCA1/2 germline mutation carriers with hormone receptors positive breast cancer

Gene expression assays are widely used to predict risk of recurrence in early breast cancer (BC). We report the 21‐gene expression assay (Oncotype Dx) recurrence score (RS) distribution of 27 BRCA carriers with estrogen receptor (ER) positive BCs, identified at Hadassah Medical Center, combined with 2 previous studies. Treatment decision and outcomes of the 27 BRCA carriers were compared with an Israeli cohort of 1594 patients published recently. We found Oncotype Dx RS low (<18), intermediate (18–30) and high (>30) among 12 (21.4%), 23 (41.1%) and 21 (37.5%) of 56 BRCA1 carriers compared with 15 (17.2%), 49 (56.3%) and 23 (26.4%) of 87 BRCA2 carriers (p = 0.2). The corresponding distribution in a population of 82,434 women published by Genomic Health was 53.4%, 36.3% and 10.3% for low, intermediate and high RS (p < 0.001 for BRCA1 and BRCA2). Treatment decision regarding chemotherapy according to RS was similar in BRCA1, BRCA2 and the control group. Two of 27 carriers had distant recurrence: a BRCA1 carrier with RS of 18 and a BRCA2 carrier with RS of 22; both have an excellent response to chemotherapy. We found an approximately ～3 fold increased rate of high RS among BRCA1 and 2 carriers with ER positive BC compared with the general BC population. These data might indicate that hormone positive BC in BRCA carriers are molecularly unique. The surprisingly good response to chemotherapy in the metastatic setting in 2 patients may suggest that the predictive value of low‐intermediate RS in carriers merits further studies.     

Prevalence of BRCA1 and BRCA2 germline mutations in young breast cancer patients: a population-based study

Our aim was to estimate the prevalence of mutations in the BRCA1 and BRCA2 genes among unselected incident cases of breast cancer in young women. We identified 158 incident breast cancer cases diagnosed before age 46 years in predefined geographic areas in Girona and Tarragona, Spain, during 1995-1997. Of these, 136 (86%) provided information on family history of cancer and were screened for BRCA1 and BRCA2 mutations. Nine of the 136 (6.6%) were found to carry BRCA deleterious mutations (MUT) (1 BRCA1 and 8 BRCA2), and 20 were detected with rare BRCA variants of unknown significance (UV). Both MUT and US BRCA alterations were more frequent in younger patients: 7 (11.6%) MUT and 12 (19.3%) UV carriers were found in the group of 62 patients younger than 40 years, whereas 2 (2.7%) MUT and 9 (12%) US carriers were identified in the group of 74 patients aged 40-45. Family history of breast and ovarian cancers suggestive of hereditary condition (at least 2 first- or second-degree relatives affected with breast cancer or at least 1 relative affected with ovarian cancer or early-onset breast cancer) was absent for 5 of 9 MUT carriers. This suggests that BRCA screening policies based on family history of cancer would miss a considerable proportion of BRCA mutations. Mutations in the BRCA1 and BRCA2 genes explain at least 10% of breast cancer cases diagnosed before age 40 years. The contribution of these genes to early-onset breast cancer is likely to be even higher given that certain UV cases might be disease-associated.     

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.     

Molecular analysis of the BRCA1 and BRCA2 genes in 32 breast and/or ovarian cancer Spanish families

It is estimated that about 5-10% of breast cancer cases may be due to inherited predisposition. Until now, two main susceptibility genes have been identified: BRCA1 and BRCA2. The first linkage and mutational studies suggested that mutations in these two genes would account for the majority of high-risk breast cancer families, but recent studies show how the proportion of families due to BRCA1 or BRCA2 mutations strongly depends on the population and the types of family analyzed. It is now clear that, in the context of families with a modest cancer profile, which are the most commonly found in the clinical practice, the percentage of mutations found is much lower than that suggested by the first studies. In the present study, we analyze a group of 32 Spanish families, which contained at least three cases of female breast cancer (at least one of them diagnosed before the age of 50 years), for the presence of mutations in the BRCA genes. The total proportion of mutations was low (25%), although the percentage of mutations in the BRCA1 and BRCA2 genes was higher, considering the breast and ovarian cancer families and the male breast cancer families respectively. Our results are in agreement with the idea that a great proportion of moderate-risk cancer families could be due to low penetrance susceptibility genes distinct from BRCA1 or BRCA2.     

High frequency of somatic missense mutation of BRCA2 in female breast cancer from Taiwan

Somatic mutation of BRCA2 has been thought to be rare in breast cancers, though common allelic deletions in the BRCA2 locus (13q12-q13) imply an important role of somatic mutation in these tumors. Reasons of the reported rare incidence could be related to very few studies focusing on the mutational analysis of BRCA2 in sporadic tumors. The mutational status of the BRCA2 gene in exon11, the largest exon harboring the RAD51 interacting BRC domains which are critical for BRCA2 function, was screened by polymerase chain reaction/single strand conformation polymorphism (PCR-SSCP) analysis followed by direct sequencing. Tumor and paired normal tissue sample from 175 patients unselected for family history or age were taken after mastectomy for breast cancer and evaluated. There were 20 mutations of BRCA2 gene in exon 11 in 15 cases (15/175, 8.6%). Most mutations we identified were point mutation (19/20, 95%), except for one nucleotide insertion. Furthermore, among these mutations, missense mutations comprised 80% (16/20) of the BRCA2 mutations. All mutations we found were novel mutation after searched in the BIC database. There were three recurrent mutations at codon 1904; and two recurrent mutations at 1907, 1936, 1937 and 1968, respectively. The mutations were associated with ductal carcinoma in situ (P=0.038) and borderline with low histological grade (P=0.072). Besides, there were three cases possessing multiple mutations in the region we studied and one of them demonstrated aggressive lymph node metastasis. These findings implicated that somatic mutations of BRCA2 genes may play a significant role in the pathogenesis of breast carcinoma in Taiwan. In addition, those events were associated with some early clinicopathological features.     

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.     

Novel BRCA1 and BRCA2 germline mutations and assessment of mutation spectrum and prevalence in Italian breast and/or ovarian cancer families

Familial aggregations of breast/ovarian cancer cases frequently depend on BRCA1/2 pathogenic mutations. Here we counselled 120 Italian breast/ovarian cancer families and selected 73 probands for BRCA1/2 mutation screening. Through this analysis we defined the prevalence of BRCA1/2 pathogenic mutations occurring in Italian breast/ovarian cancer families, enlarged the spectrum of Italian BRCA1/2 mutations by 15% and report on the identification of 13 novel variants, including two deleterious truncating mutations and two potentially pathogenic missense mutations, on the BRCA1 and BRCA2 genes. Finally in hereditary breast cancer families with three or more female breast cancer cases we observed a low mutation prevalence and a significant association with BRCA2 mutations.     

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.     

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.     

The efficacy of taxane chemotherapy for metastatic breast cancer in BRCA1 and BRCA2 mutation carriers

BACKGROUND:

We assessed the efficacy of taxane chemotherapy in BRCA1‐ and BRCA2‐associated patients compared with sporadic metastatic breast cancer patients.

METHODS:

Response rates (RRs) to and progression‐free survival (PFS) after taxane chemotherapy of 35 BRCA1‐associated and 13 BRCA2‐associated metastatic breast cancer patients were compared with those outcomes in 95 matched (1:2) sporadic patients. Matching was performed for age at and year of diagnosis of primary breast cancer, year of metastatic disease, and line of therapy (first vs second or third).

RESULTS:

Among BRCA1‐associated patients, the RR was worse (objective response [OR], 23% vs 38%; progressive disease [PD], 60% vs 19%; P < 0.001); and the median PFS shorter (2.2 vs 4.9 months; P = 0.04) compared with sporadic patients. In the subgroup of hormone receptor (HRec)‐negative patients, BRCA1‐associated patients (n = 20) had a worse RR (OR, 20% vs 42%, respectively; PD, 70% vs 26%, respectively; P = 0.03) and a shorter PFS (1.8 vs 3.8 months; P = 0.004) compared with sporadic patients (n = 19). These outcomes in HRec‐positive patients were similar in BRCA1‐associated (n = 11) and sporadic (n = 61) patients (OR, 36% vs 38%; PD, 28% vs 20%; median PFS, both 5.7 months). In BRCA2‐associated patients, who were mainly HRec‐positive, the OR was higher than in sporadic patients (89% vs 38%, respectively; P = 0.02), whereas the median PFS was not significantly different (7.1 vs 5.7 months, respectively).

CONCLUSIONS:

BRCA1‐associated, HRec‐negative metastatic breast cancer patients were less sensitive to taxane chemotherapy than sporadic HRec‐negative patients. HRec‐positive BRCA1‐ and BRCA2‐associated patients had a sensitivity to taxane chemotherapy similar to that of sporadic patients. Cancer 2012;. © 2011 American Cancer Society.     

Identification of a founder <Emphasis Type="Italic">BRCA2</Emphasis> mutation in Sardinian breast cancer families

The population of Sardinia is characterized by a relatively low level of genetic heterogeneity: therefore ‘founder mutations’ can be expected to be found. We analysed 17 probands from families with high incidence of breast cancer or breast and ovarian cancer by sequencing the full-length coding regions of BRCA1 and BRCA2 genes. A novel BRCA2 frameshift mutation, 3951del3insAT, which produces a protein truncated at codon 1258, was observed in six patients with BC from the same village. The mutation was not found in unaffected females (matched on basis of ethnicity and age) with no family history of cancer. Haplotype analysis strongly suggests that all affected persons had a common ancestor. The identification of this clinically significant founder mutation may facilitate screening/testing for inherited risk of breast cancer.