Impact of the addition of carboplatin to anthracycline-taxane-based neoadjuvant chemotherapy on survival in BRCA1/2-mutated triple-negative breast cancer.

Whether adding carboplatin to standard neoadjuvant chemotherapy improves survival in BRCA1/2-mutated triple-negative breast cancer (TNBC) is unknown. In this retrospective study, we aimed to explore the efficacy of anthracycline-taxane (A-T)-based or anthracycline-taxane/carboplatin (A-TP)-based neoadjuvant chemotherapy in BRCA1/2-mutated TNBC. A total of 1585 operable primary breast cancer patients were treated with either neoadjuvant A-T (n = 886) or A-TP regimen (n = 699). BRCA1 and BRCA2 germline mutations were determined in all subjects. Pathological complete response (pCR), recurrence-free survival (RFS), distant recurrence-free survival (DRFS) and overall survival (OS) were estimated. Of the entire cohort, 102 patients (6.4%) carried a pathogenic BRCA1/2 germline mutation. After a median follow-up of 81 months, no significant differences in survival between the A-T and A-TP arms were found in the entire cohort. However, among 288 TNBC patients, BRCA1/2 mutation carriers had significantly better survival when treated with the A-TP regimen than with the A-T regimen (5-year RFS: 82.6% vs 47.9%; P = .024; 5-year DRFS: 88.5% vs 46.9%; P = .010; 5-year OS: 88.2% vs 49.9%; P = .036). Multivariate analyses revealed that the A-TP regimen was a significantly favourable factor for RFS and DRFS and showed a trend towards better OS when compared with the A-T regimen in BRCA1/2-mutated TNBC (RFS: adjusted hazard ratio [HR], 0.24; 95% confidence interval [CI], 0.06-0.91, P = .035; DRFS: HR, 0.17; 95% CI, 0.03-0.80; P = .025; OS: HR, 0.29; 95% CI, 0.06-1.49; P = .14). Our study suggested that BRCA1/2-mutated TNBC patients gain a survival benefit when carboplatin is added to standard A-T-based neoadjuvant chemotherapy.

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.

BRCA1 c.5470_5477del, a founder mutation in Chinese Han breast cancer patients.

The spectrum and frequency of BRCA1/2 pathogenic variants may be ethnicity-specific. Whether high-frequency founder mutations are present in Chinese women remains largely unknown. In the current study, germline pathogenic variants in the BRCA1/2 genes were determined in 9,505 unselected Chinese Han breast cancer (BC) patients by next-generation and/ or Sanger sequencing. Four hundred and seventy-one (5.0%) BC patients carried BRCA1/2 pathogenic variants in this cohort. A total of 25 recurrent pathogenic variants (at least found in four unrelated patients) were identified in this cohort (8 BRCA1 and 17 BRCA2 recurrent pathogenic variants), 161 patients carried one of these recurrent pathogenic variants in this cohort of 9,505 patients. All of these 25 recurrent pathogenic variants were further explored whether they had founder effect through haplotype analysis. The most common pathogenic variant, BRCA1 c.5470_5477del, was found in 30 BC patients from 29 unrelated families. Twenty-seven of these 29 unrelated patients who carried this BRCA1 c.5470_5477del mutation shared an identical haplotype, indicating that BRCA1 c.5470_5477del was a founder mutation in the Chinese Han population. Furthermore, BRCA1 c.5470_5477del mutation carriers had a significantly worse survival than noncarriers (disease-free survival, p = 0.049; overall survival, p = 0.029). Taken together, our data suggested that BRCA1 c.5470_5477del is a founder mutation in the Chinese Han population and BRCA1 c.5470_5477del mutation carriers have a poor survival.

Prevalence and clinical impact of TP53 germline mutations in Chinese women with breast cancer.

The prevalence and clinical relevance of TP53 germline mutations in a large unselected breast cancer series are largely unknown. Here, we determined TP53 germline mutations in a large cohort of 10,053 unselected breast cancer patients through multigene panel-based next-generation and/or Sanger sequencing assays. We found that 0.5% of patients (50 cases) carried a pathogenic TP53 germline mutation in this large series of 10,053 unselected breast cancer patients, and the prevalence of TP53 germline mutation was 3.8% in very early onset breast cancer (age ≤30 years) in this large cohort. TP53 mutation carriers were significantly more likely to have early onset cancer (p < 0.001) and bilateral breast cancer (p = 0.03), they and were significantly more likely to respond to carboplatin-based neoadjuvant chemotherapy compared to anthracycline- or taxane-based regimen in terms of pathologic complete response (50% vs. 0%, p = 0.006). At the median follow-up of 54 months, TP53 mutation was an independent unfavorable factor for recurrence-free survival (RFS), distant recurrence-free survival (DRFS), and overall survival (OS) (RFS, adjusted hazard ratio [HR]: 2.24, 95% confidence interval [CI]: 1.15-4.33, p = 0.02; DRFS, adjusted HR: 2.73, 95% CI: 1.41-5.30, p = 0.003; OS, adjusted HR: 4.60, 95% CI: 2.26-9.41, p < 0.001) in multivariate analyses. Our study suggested that TP53 germline mutations occur more frequently in very early onset unselected breast cancer patients; and TP53 germline mutation carriers have a very poor survival and may benefit from carboplatin-based neoadjuvant chemotherapy in unselected breast cancer patients.

Spectrum and clinical relevance of PALB2 germline mutations in 7657 Chinese BRCA1/2-negative breast cancer patients.

PURPOSE: To investigate the prevalence and clinical relevance of PALB2 germline mutations in BRCA1/2-negative breast cancer patients. METHODS: The exons and intron-exon boundaries of the PALB2 gene were sequenced by multigene panel testing in a cohort of 7657 Chinese BRCA1/2-negative breast cancer patients. RESULTS: Of the 7657 patients, 54 (0.71%) carried pathogenic PALB2 germline mutations, all of which were nonsense or frameshift mutations leading to a truncated protein. The 54 patients carried 42 distinct pathogenic mutations, of which 17 (40.5%) were novel and 8 were recurrent mutations. Compared with non-carriers, PALB2 pathogenic mutation carriers developed breast cancer at a younger age (47.52 years vs. 51.35 years, p = 0.016) and were more likely to have triple-negative (24.1% vs. 13.4%, p = 0.022) or HER2 negative (87.0% vs. 74.2%, p = 0.031) breast cancer and large breast tumors (> 2 cm) at diagnosis (72.2% vs. 57.0%, p = 0.024). PALB2 mutation carriers were also more likely to have family histories of breast and/or ovarian cancer (27.8% vs. 8.4%, p < 0.001) and any types of cancer (57.4% vs. 31.6%, p < 0.001) when compared with non-carriers. CONCLUSIONS: PALB2 germline mutations are present at 0.71% in Chinese BRCA1/2-negative breast cancer patients and are more frequent in patients with triple-negative breast cancer and family histories of breast and/or ovarian cancer.

Germline mutation in DNA-repair genes is associated with poor survival in BRCA1/2-negative breast cancer patients.

BRCA1/2 genes are the most frequently germline mutated DNA-repair genes, and the survival of BRCA1/2 carriers has been extensively explored in breast cancer. However, the prevalence of germline mutations in non-BRCA1/2 DNA-repair genes and the survival of carriers are largely unknown in a large cohort of unselected breast cancer patients. Germline mutations in 16 DNA-repair genes were determined using a multigene panel in 7657 BRCA1/2-negative breast cancer patients who were unselected for family history of cancer or age at diagnosis. Among the 7657 BRCA1/2-negative breast cancer patients, 257 (3.4%) carried at least 1 pathogenic germline mutation in the 16 DNA-repair genes. The prevalence of DNA-repair gene mutations was significantly higher in familial breast cancers (5.2%, P = 0.002) and early-onset breast cancers (diagnosed at and before the age of 40) (4.5%, P = 0.003) than that of sporadic breast cancers (2.9%) (diagnosed above age of 40), respectively. The DNA-repair gene mutation carriers were significantly more likely to have a larger tumor (P = 0.04) and axillary lymph node metastasis (P = 0.03). Moreover, DNA-repair gene mutation was an independent unfavorable factor for recurrence-free survival (adjusted hazard ratio [HR] = 1.38, 95% CI: 1.00-1.91, P = 0.05) and disease-specific survival (adjusted HR=1.63, 95% CI: 1.04-2.57, P = 0.03) in this cohort. Overall, 3.4% of BRCA1/2-negative breast cancer patients carried germline mutations in the 16 DNA-repair genes, and the DNA-repair gene mutation carriers exhibited an aggressive phenotype and had poor survival compared with noncarriers.

Prevalence and characterization of ATM germline mutations in Chinese BRCA1/2-negative breast cancer patients.

PURPOSE: The ataxia telangiectasia-mutated (ATM) gene is a moderate susceptibility gene for breast cancer. However, little is known about the breast cancer phenotypes associated with ATM mutation. We therefore investigated the spectrum and clinical characteristics of ATM germline mutations in Chinese breast cancer patients. METHODS: A multi-gene panel was performed to screen for ATM germline mutations in 7657 BRCA1/2-negative breast cancer patients. All deleterious mutations were validated by independent polymerase chain reaction (PCR)-Sanger sequencing. RESULTS: A total of 31 pathogenic mutations in the ATM gene across 30 carriers were identified, and the ATM mutation rate was 0.4% (30/7,657) in this cohort. The majority of the mutations (90.3%, 28/31) were nonsense or frameshift mutations. Of the total ATM mutations, 61.3% (19/31) were novel mutations and 13 recurrent mutations were found. ATM mutations carriers were significantly more likely to have a family history of breast and/or ovarian cancer (26.7% in carriers vs. 8.6% in non-carriers, p < 0.001), as well as a family history of any cancer (60.0% in carriers vs. 31.5% in non-carriers, p = 0.001). In addition, ATM mutations carriers were significantly more likely to have oestrogen receptor (ER)-positive (p = 0.011), progesterone receptor (PR)-positive (p = 0.040), and lymph node-positive breast cancer (p = 0.034). CONCLUSIONS: The prevalence of the ATM mutation is approximately 0.4% in Chinese BRCA1/2-negative breast cancer. ATM mutation carriers are significantly more likely to have a family history of cancer and to develop ER- and/or PR-positive breast cancer or lymph node-positive breast cancer.

RAD50 germline mutations are associated with poor survival in BRCA1/2-negative breast cancer patients.

RAD50 is a highly conserved DNA double-strand break (DSB) repair gene. However, the associations between RAD50 germline mutations and the survival and risk of breast cancer have not been fully elucidated. Here, we aimed to investigate the clinical impact of RAD50 germline mutations in a large cohort of unselected breast cancer patients. In our study, RAD50 germline mutations were determined using next-generation sequencing in 7657 consecutive unselected breast cancer patients without BRCA1/2 mutations. We also screened for RAD50 recurrent mutations (L719fs, K994fs, and H1269fs) in 5000 healthy controls using Sanger sequencing. We found that 26 out of 7,657 (0.34%) patients had RAD50 pathogenic mutations, and 16 patients carried one of the three recurrent mutations (L719fs, n = 6 cases; K994fs, n = 5 cases; and H1269fs, n = 5 cases); the recurrent mutation rate was 0.21%. The frequency of the three recurrent mutations in the 5,000 healthy controls was 0.18% (9/5,000). These mutations did not confer an increased risk of breast cancer in the studied patients [odds ratios (OR), 1.16; 95% confidence interval (CI), 0.51-2.63; p = 0.72]. Nevertheless, multivariate analysis revealed that RAD50 pathogenic mutations were an independent unfavourable predictor of recurrence-free survival (RFS) [adjusted hazard ratio (HR) 2.66; 95% CI, 1.18-5.98; p = 0.018] and disease-specific survival (DSS; adjusted HR 4.36; 95% CI, 1.58-12.03; p = 0.004) in the entire study cohort. Our study suggested that RAD50 germline mutations are not associated with an increased risk of breast cancer, but patients with RAD50 germline mutations have unfavourable survival compared to patients without these mutations.

Predictive value of BRCA1/2 mRNA expression for response to neoadjuvant chemotherapy in BRCA-negative breast cancers.

It is well known that BRCA1 and BRCA2 play a central role in DNA repair, but the relationship between BRCA1 and BRCA2 mRNA expression and response to neoadjuvant chemotherapy in sporadic breast cancer patients has not been well established. Here, we investigate the association between BRCA1 or BRCA2 mRNA expression levels and pathological response in 674 BRCA1/2 mutation-negative breast cancer patients who received neoadjuvant chemotherapy. BRCA1 and BRCA2 mRNA expression were assessed using quantitative real-time polymerase chain reaction in core biopsy breast cancer tissue obtained prior to the initiation of neoadjuvant chemotherapy. A total 129 patients (19.1%) achieved pathological complete response (pCR) after neoadjuvant chemotherapy. Among patients treated with anthracycline-based chemotherapy (n = 531), BRCA1 mRNA low expression patients had a significantly higher pCR rate than intermediate or high BRCA1 mRNA expression groups (24.6% vs 16.8% or 14.0%, P = .031) and retained borderline significance (OR = 1.54, 95% CI = 0.93-2.56, P = .094) in multivariate analysis. Among the 129 patients who received a taxane-based regimen, pCR rate showed no differences in BRCA1 low, intermediate, and high mRNA level subgroups (19.6%, 26.8% and 21.4%, respectively; P = .71). BRCA2 mRNA level was not associated with pCR rate in the anthracyline-based treated subgroup (P = .60) or the taxane-based regimen subgroup (P = .82). Taken together, our findings suggested that BRCA1 mRNA expression could be used as a predictive marker in BRCA1/2 mutation-negative breast cancer patients who received neoadjuvant anthracycline-based treatment.

Identification and analysis of CHEK2 germline mutations in Chinese BRCA1/2-negative breast cancer patients.

PURPOSE: Cell-cycle-checkpoint kinase 2 (CHEK2) is an important moderate-penetrance breast cancer predisposition gene; however, recurrent CHEK2 mutations found in Caucasian women are very rare in Chinese population. We investigated the mutation spectrum and clinical relevance of CHEK2 germline mutations in Chinese breast cancer patients. METHODS: The entire coding regions and splicing sites of CHEK2 were screened in 7657 Chinese BRCA1/2-negative breast cancer patients, using 62-gene panel-based sequencing. RESULTS: Out of 7657 BRCA1/2-negative breast cancer patients, 26 (0.34%) carried CHEK2 pathogenic germline mutations. Most of these mutations (92.3%, 24/26) were nonsense or frameshift mutations; 84.6% (22/26) of them were in forkhead-associated (FHA) or kinase domains. Of the 18 types of CHEK2 mutations we found, 61.1% (11/18) of were novel mutations and two recurrent mutations (Y139X and R137X) were found in this cohort. Patients with CHEK2 mutations were significantly more likely to have family histories of breast and/or ovarian cancer (23.1% vs. 8.6%, p = 0.022) and family histories of any cancer (50.0% vs. 31.6%, p = 0.044); and were significantly more likely to have lymph node-positive (53.8% vs. 27.3%, p = 0.002) and progesterone receptor (PR)-positive (88.5% vs. 64.5%, p = 0.011) breast cancers. CONCLUSIONS: Among Chinese breast cancer patients, the CHEK2 germline mutation rate is approximately 0.34% and two specific mutations (Y139X and R137X) are recurrent. Patients with CHEK2 mutations are significantly more likely to have family histories of cancer, and to develop lymph node-positive and/or PR-positive breast cancers.

Low expression of RECQL is associated with poor prognosis in Chinese breast cancer patients.

BACKGROUND: RECQL is a number of the RecQ DNA helicase family and plays an important role in maintaining genome stability. Although several studies have reported that RECQL mutations were correlated with the susceptibility to breast cancer, the effect on prognosis in breast cancer was not yet clarified. Here, we explored the association between RECQL expression level and survival in patients with breast cancer. METHODS: In the first cohort, the RECQL mRNA expression level was evaluated in 774 primary breast cancer patients using a quantitative real-time PCR assay. Then, in the second independent cohort, the level of RECQL protein expression was detected in 322 patients with breast cancer using immunohistochemistry assay. Survival curves of patients with RECQL expression were compared using the Kaplan-Meier method with log-rank test. RESULTS: In the first cohort of 774 breast cancer patients, the low expression level of RECQL mRNA was significantly correlated with aggressive clinicopathological characteristics, including the positive lymph node status (P = 0.026), HER2 overexpression (P < 0.001), ER negative status (P = 0.047) and high tumor grade (P = 0.041). Moreover, the low expression level of RECQL mRNA was significantly associated with poor distant recurrence-free survival (DRFS, unadjusted hazard ratio (HR): 2.77, 95% confidence interval (CI): 1.88-4.09, P < 0.001) and disease-specific survival (DSS, unadjusted HR: 3.10, 95% CI: 1.84-5.20,P < 0.001), and it remained an independent unfavorable factor for DRFS and DSS (DRFS: adjusted HR: 3.04, 95% CI: 1.89-4.87, P < 0.001; DSS: adjusted HR: 4.25, 95% CI: 2.12-8.46, P < 0.001). In the second cohort of 322 breast cancer patients, low expression of RECQL protein was also subject to poor survival in breast cancer, and it was an independent prognosis factor of poor DRFS by multivariate analysis (DRFS: adjusted HR: 2.12, 95% CI: 1.16-3.88, P = 0.015). CONCLUSIONS: Breast cancer patients with low RECQL expression had a worse survival. The expression level of RECQL may be a potential prognosis factor for breast cancer.

Mutations in RECQL Gene Are Associated with Predisposition to Breast Cancer.

The genetic cause for approximately 80% of familial breast cancer patients is unknown. Here, by sequencing the entire exomes of nine early-onset familial breast cancer patients without BRCA1/2 mutations (diagnosed with breast cancer at or before the age of 35) we found that two index cases carried a potentially deleterious mutation in the RECQL gene (RecQ helicase-like; chr12p12). Recent studies suggested that RECQL is involved in DNA double-strand break repair and it plays an important role in the maintenance of genomic stability. Therefore, we further screened the RECQL gene in an additional 439 unrelated familial breast cancer patients. In total, we found three nonsense mutations leading to a truncated protein of RECQL (p.L128X, p.W172X, and p.Q266X), one mutation affecting mRNA splicing (c.395-2A>G), and five missense mutations disrupting the helicase activity of RECQL (p.A195S, p.R215Q, p.R455C, p.M458K, and p.T562I), as evaluated through an in vitro helicase assay. Taken together, 9 out of 448 BRCA-negative familial breast cancer patients carried a pathogenic mutation of the RECQL gene compared with one of the 1,588 controls (P = 9.14×10-6). Our findings suggest that RECQL is a potential breast cancer susceptibility gene and that mutations in this gene contribute to familial breast cancer development.

HER2 somatic mutations are associated with poor survival in HER2-negative breast cancers.

It is well documented that human epidermal growth factor receptor 2 (HER2) overexpression/amplification is associated with poor survival in breast cancer patients. However, it is largely unknown whether HER2 somatic mutations are associated with survival in HER2-negative breast cancer patients. Here, we identified HER2 somatic mutations in tumors from 1348 unselected breast cancer patients by sequencing the entire HER2 coding region. All of these mutations were tested for in corresponding blood samples to determine whether they were somatic or germline mutations. We further investigated the associations between HER2 somatic mutations and recurrence-free survival and distant recurrence-free survival in this cohort of patients. We found that 27 of 1348 (2.0%) of these patients carried a HER2 somatic mutation. In vitro experiments indicated that some of the novel mutations and those with unknown functions increased HER2 activity. HER2 status was available for 1306 patients, and the HER2 somatic mutation rates in HER2-positive (n = 353) and HER2-negative breast cancers (n = 953) were 1.4% and 2.3%, respectively. Among the HER2-negative patients, those with a HER2 somatic mutation had a significantly worse recurrence-free survival (unadjusted hazard ratio = 2.67; 95% confidence interval, 1.25-5.72, P = 0.002) and distant recurrence-free survival (unadjusted hazard ratio = 2.50; 95% confidence interval, 1.10-5.68, P = 0.004) than those with wild-type HER2. Taken together, our findings suggested that HER2 somatic mutations occur at a higher frequency in HER2-negative breast cancer, and HER2-negative breast cancer patients with these mutations have poor survival. Therefore, HER2-negative patients with a HER2 somatic mutation are potentially good candidates for HER2-targeted therapy.

TP53 mutations are associated with higher rates of pathologic complete response to anthracycline/cyclophosphamide-based neoadjuvant chemotherapy in operable primary breast cancer.

The role of TP53 mutations in predicting response to neoadjuvant chemotherapy in breast cancer remains controversial. The aims of this study were to investigate whether TP53 mutations were associated with response and survival in breast cancer patients who received neoadjuvant chemotherapy. Therefore, we identified TP53 mutations in the core-needle biopsy tumor samples obtained before the neoadjuvant chemotherapy from 351 operable primary breast cancer patients who either received anthracycline/cyclophosphamide-based (n = 252) or paclitaxel (n = 99) neoadjuvant chemotherapy. We found that 41.0% (144 of 351) of patients harbored TP53 mutations, and 14.8% of patients achieved a pCR (pathologic complete response) after neoadjuvant chemotherapy. Among patients treated with anthracycline/cyclophosphamide (n = 252), patients with TP53 mutations had a significantly higher pCR rate than those with wild-type (28.6 vs.7.1%; p < 0.001), and TP53 mutation was an independent favorable predictor of pCR [odds ratio (OR) = 3.41; 95% confidence interval (CI) 1.50-7.77; p = 0.003] in this group; moreover, patients with TP53 mutation had a better distant recurrence-free survival (DRFS) than those with wild-type [unadjusted hazard ratio (HR) = 0.43; 95% CI 0.20-0.94; p = 0.030] in this group. Among patients treated with paclitaxel (n = 99), no significant difference in pCR rates was observed between patients with or without TP53 mutations (15.2 vs. 11.3%; p = 0.57). Our results suggested that patients with TP53 mutations are more likely to respond to anthracycline/ cyclophosphamide-based neoadjuvant chemotherapy and have a favorable survival.

Comprehensive analysis of BRCA1 and BRCA2 germline mutations in a large cohort of 5931 Chinese women with breast cancer.

We determined the prevalence and characteristics of BRCA1/2 germline mutations in a large cohort of Chinese women with breast cancer. A total of 5931 unselected Chinese women with breast cancer were enrolled in this study and underwent testing for BRCA1/2 mutations. Of these, 543 patients were familial breast cancer, 1033 were early-onset disease (≤40 years) without family history of breast cancer, and 4355 were sporadic breast cancer. In total, 232 patients (3.9 %) carried a BRCA1 or BRCA2 mutation (110 in BRCA1and 122 in BRCA2) in this cohort of 5931 patients. BRCA1/2 mutation rate was 16.9 % (92/543) in familial breast cancers, 5.2 % (54/1033) in early-onset breast cancers (≤40 years), and 2.0 % in sporadic breast cancers (>40 years), respectively. The BRCA1/2 mutation rate was 27.0 % in 111 familial breast cancers diagnosed at and before the age of 40. 41.4 % of mutations in this cohort were specific for Chinese population. Recurrent mutations accounted for 44.8 % of the entire mutations in 2382 cases that BRCA1 and BRCA2 genes were fully sequenced in this study. Both BRCA1 and BRCA2 mutation carriers were significantly more likely to be early-onset and bilateral breast cancers, high-grade cancer, and to have a family history of breast cancer compared with non-carriers. BRCA1 mutation carriers were more likely to be triple-negative cancer than BRCA2 mutation carriers and non-carriers. Our data provide guidelines for Chinese women with breast cancer who should undergo BRCA1/2 genetic testing; additionally, recurrent mutations account for nearly half of the mutations and some of them are specific for Chinese women.

Breast cancer risk in Chinese women with BRCA1 or BRCA2 mutations.

BRCA1/2 mutations represent approximately 5 % of unselected Chinese women with breast cancer. However, the breast cancer risk of Chinese women with BRCA1/2 mutations is unknown. Therefore, the aim of this study was to estimate the age-specific cumulative risk of breast cancer in Chinese women who carry a BRCA1 or BRCA2 mutation. Our study included 1816 unselected Chinese women with breast cancer and 5549 female first-degree relatives of these probands. All probands were screened for BRCA1/2 mutation. The age-specific cumulative risks of BRCA1/2 carriers were estimated using the kin-cohort study by comparing the history of breast cancer in first-degree female relatives of BRCA1/2 carriers and non-carriers. Among the 1816 probands, 125 BRCA1/2 pathogenic mutations were identified (70 in the BRCA1 gene and 55 in the BRCA2 gene). The incidence of breast cancer in the first-degree female relatives of BRCA1/2 mutation carriers was significantly higher (3.7-fold and 4.4-fold for BRCA1 and BRCA2 mutation carriers, respectively) than in non-carriers. The estimated cumulative risks of breast cancer by age 70 years were 37.9 % [95 % confidence interval (CI) 24.1-54.4 %] for BRCA1 mutation carriers and 36.5 % (95 % CI 26.7-51.8 %) for BRCA2 mutation carriers, respectively. Our study suggests that the breast cancer risk of Chinese women with BRCA1/2 mutations appears to be relatively high by the age of 70. Therefore, genetic counseling, enhanced surveillance, and individual preventive strategies should be provided for Chinese women who carry a BRCA1/2 mutation.

Association between CHEK2 H371Y mutation and response to neoadjuvant chemotherapy in women with breast cancer.

BACKGROUND: Our previous study suggested that the recurrent CHEK2 H371Y mutation is a novel pathogenic mutation that confers an increased risk of breast cancer. The purpose of this study was to investigate whether breast cancer patients with CHEK2 H371Y mutation were more likely to respond to neoadjuvant chemotherapy. METHODS: We screened a cohort of 2334 Chinese women with operable primary breast cancer who received a neoadjuvant chemotherapy regimen for CHEK2 H371Y germline mutations. Pathologic complete response (pCR) was defined as the absence of tumor cells in the breast after the completion of neoadjuvant chemotherapy. RESULTS: Thirty-nine patients (1.7%) with CHEK2 H371Y germline mutation were identified in this cohort of 2334 patients. CHEK2 H371Y mutation carriers had a significantly higher pCR rate than non-carriers (33.3% versus 19.5%, P = 0.031) in the entire study population, and CHEK2 H371Y mutation-positive status remained an independent favorable predictor of pCR in a multivariate analysis (odds ratio [OR] = 3.01; 95% confidence interval [CI]: 1.34- 6.78, P = 0.008). CHEK2 H371Y carriers had a slightly worse distant recurrence-free survival than non-carriers (adjusted hazard ratio [HR] =1.24, 95% CI: 0.59-2.63). CONCLUSIONS: CHEK2 H371Y mutation carriers are more likely to respond to neoadjuvant chemotherapy than are non-carriers.

Breast-conserving therapy and modified radical mastectomy for primary breast carcinoma: a matched comparative study.

BACKGROUND: To compare two types of therapy for primary breast carcinoma, breast-conserving therapy (BCT) and modified radical mastectomy (MRM), in a matched cohort study. METHODS: A series of 1,746 patients with primary breast cancer treated with BCT or MRM in a single Chinese institute between January 2000 and February 2009 were analyzed retrospectively to compare their outcomes with respect to the incidence of local recurrence (LR), distant metastasis, and survival. The patients were matched with regard to age at diagnosis, spreading to axillary lymph nodes, hormone receptor status, the use of neoadjuvant chemotherapy and maximal tumor diameter. The match ratio was 1:1, and each arm included 873 patients. RESULTS: The median follow-up period was 71 months. The 6-year disease-free survival (DFS) and 6-year distant disease-free survival (DDFS) rates differed significantly between two groups. The 6-year local recurrence-free survival (LRFS) rates were 98.2% [95% confidence interval (CI): 0.973-0.989] in the BCT group and 98.7% (95% CI: 0.980-0.994) in the MRM group (P=0.182), respectively. DFS rates in BCT and MRM groups were 91.3% (95% CI: 0.894-0.932) and 86.3% (95% CI: 0.840-0.886) (P<0.001), respectively, whereas the DDFS rates in BCT and MRM groups were 93.6% (95% CI: 0.922-0.950) and 87.7% (95% CI: 0.854-0.900) (P<0.001), respectively. CONCLUSIONS: BCT in eligible patients is as effective as MRM with respect to local tumor control, DFS and DDFS, and may result in a better outcome than MRM in Chinese primary breast cancer patients.

Association between HER2 status and response to neoadjuvant anthracycline followed by paclitaxel plus carboplatin chemotherapy without trastuzumab in breast cancer.

BACKGROUND: We recently showed HER2-positive breast cancers are less likely to respond to neoadjuvant anthracycline chemotherapy. Here, we investigated whether HER2-positive breast cancers responded to sequential neoadjuvant anthracycline followed by paclitaxel plus carboplatin regimen in the absence of trastuzumab. METHODS: Women (n=372) with operable primary breast cancer initially received two cycles of neoadjuvant anthracyclines, the clinical tumor response was assessed, then patients were received four cycles of paclitaxel plus carboplatin regimen. All the patients did not received trastuzumab treatment in the neoadjuvant setting. HER2 status was determined by immunohistochemistry and/or by fluorescence in situ hybridization in core-biopsy breast cancer tissue obtained before the neoadjuvant chemotherapy. RESULTS: Eighteen percent (67/372) of patients achieved a pathologic complete response (pCR) in their breast. HER2-positive tumors had a significant higher pCR rate than HER2-negative tumors (33.0% versus 13.5%, P<0.001) in this cohort of 372 patients, and positive HER2 status remained an independent favorable predictor of pCR in a multivariate analysis [odds ratio (OR), 2.26; 95% confidence interval (CI), 1.18 to 4.36, P=0.015]. Furthermore, patients who responded to initial anthracycline regimens were more likely to respond to paclitaxel plus carboplatin than patients who did not (pCR, 27.2% versus 14.6%, P=0.005). Patients with HER2-positive tumors exhibited a significant higher pCR rate than did patients with HER2-negative tumors in both anthracycline response group (40.5% versus 20.0%, P=0.025) and anthracycline non-response group (28.3% versus 11.3%, P=0.002). CONCLUSIONS: Under the circumstance of no trastuzumab treatment, women with HER2-positive cancers derive a large benefit from paclitaxel-carboplatin-based neoadjuvant chemotherapy.

Value of pre-treatment biomarkers in prediction of response to neoadjuvant endocrine therapy for hormone receptor-positive postmenopausal breast cancer.

OBJECTIVE: To determine the predictive ability of biomarkers for responses to neoadjuvant endocrine therapy (NET) in postmenopausal breast cancer. METHODS: Consecutive 160 postmenopausal women with T1-3N0-1M0 hormone receptor (HR)-positive invasive breast cancer were treated with anastrozole for 16 weeks before surgery. New slides of tumor specimens taken before and after treatment were conducted centrally for biomarker analysis and classified using the Applied Imaging Ariol MB-8 system. The pathological response was evaluated using the Miller & Payne classification. The cell cycle response was classified according to the change in the Ki67 index after treatment. Multivariable logistic regression analysis was used to calculate the combined index of the biomarkers. Receiver operating characteristic (ROC) curves were used to determine whether parameters may predict response. RESULTS: The correlation between the pathological and cell cycle responses was low (Spearman correlation coefficient =0.241, P<0.001; Kappa value =0.119, P=0.032). The cell cycle response was significantly associated with pre-treatment estrogen receptor (ER) status (P=0.001), progesterone receptor (PgR) status (P<0.001), human epidermal growth factor receptor 2 (Her-2) status (P=0.050) and the Ki67 index (P<0.001), but the pathological response was not correlated with these factors. Pre-treatment ER levels [area under the curve (AUC) =0.634, 95% confidence interval (95% CI), 0.534-0.735, P=0.008] and combined index of pre-treatment ER and PgR levels (AUC =0.684, 95% CI, 0.591-0.776, P<0.001) could not predict the cell cycle response, but combined index including per-treatment ER/PR/Her-2/Ki67 expression levels could (AUC =0.830, 95% CI, 0.759-0.902, P<0.001). CONCLUSIONS: The combined use of pre-treatment ER/PgR/Her-2/Ki67 expression levels, instead of HR expression levels, may predict the cell cycle response to NET.