A multicentre randomised controlled trial of the McGrath Mac videolaryngoscope versus conventional laryngoscopy

Before completion of this study, there was insufficient evidence demonstrating the superiority of videolaryngoscopy compared with direct laryngoscopy for elective tracheal intubation. We hypothesised that using videolaryngoscopy for routine tracheal intubation would result in higher first-pass tracheal intubation success compared with direct laryngoscopy. In this multicentre randomised trial, 2092 adult patients without predicted difficult airway requiring tracheal intubation for elective surgery were allocated randomly to either videolaryngoscopy with a Macintosh blade (McGrath) or direct laryngoscopy. First-pass tracheal intubation success was higher with the McGrath (987/1053, 94%), compared with direct laryngoscopy (848/1039, 82%); absolute risk reduction (95%CI) was 12.1% (10.9-13.6%). This resulted in a relative risk (95%CI) of unsuccessful tracheal intubation at first attempt of 0.34 (0.26-0.45; p < 0.001) for McGrath compared with direct laryngoscopy. Cormack and Lehane grade ≥ 3 was observed more frequently with direct laryngoscopy (84/1039, 8%) compared with McGrath (8/1053, 0.7%; p < 0.001) No significant difference in tracheal intubation-associated adverse events was observed between groups. This study demonstrates that using McGrath videolaryngoscopy compared with direct laryngoscopy improves first-pass tracheal intubation success in patients having elective surgery. Practitioners may consider using this device as first choice for tracheal intubation.

Impact of direct laryngoscopy vs. videolaryngoscopy on signal quality of recurrent laryngeal nerve monitoring in thyroid surgery: a randomised parallel group trial

In thyroid surgery, intra-operative neuromonitoring signals of the recurrent laryngeal nerve can be detected by surface electrodes on a tracheal tube positioned at the vocal fold level. The incidence of difficult tracheal intubation in patients undergoing thyroidectomy for nodular goitre ranges from 5.3% to 20.5%. The aim of this study was to compare videolaryngoscopy with conventional direct laryngoscopy as methods for proper placement of the surface electrode to prevent insufficient intra-operative nerve signal quality. In this prospective randomised trial, adult patients requiring tracheal intubation during thyroid surgery were randomly allocated to two groups of C-MAC^® (Macintosh style blade) videolaryngoscope or direct laryngoscopy using the Macintosh laryngoscope. Primary outcome was the incidence of insufficient signal electromyogram amplitude level (< 500 μV) after successful tracheal intubation. A total of 260 (130 per group) participants were analysed. An insufficient signal was more frequent with direct laryngoscopy (35/130, 27%), compared with C-MAC (12/130, 9%, p < 0.001). First-pass tracheal intubation success rate was lower with direct laryngoscopy (86/130 (66%)) compared with the C-MAC (125/130 (96%)) (p < 0.0001). Cormack and Lehane grade ≥ 3 was observed more frequently with direct laryngoscopy (16/130 (12%)), compared with the C-MAC (0/130, (0%)) (p < 0.0001). The results suggest that videolaryngoscopy has an impact on the quality of the initial intra-operative neuromonitoring signal in patients undergoing thyroid surgery, and this technique can provide optimised surface electrode positioning.

Non-invasive haemoglobin measurement as an index test to detect pre-operative anaemia in elective surgery patients - a prospective study

Non-invasive haemoglobin measurement using absolute values lacks the precision to be the sole basis for the treatment of pre-operative anaemia. However, it can possibly serve as a screening test, indexing 'anaemia' with high sensitivity when values remain under prespecified cut-off values. Based on previous data, non-invasive haemoglobin cut-off values (146 g.l^-1 for women and 152 g.l^-1 for men) detect true anaemia with 99% sensitivity. An index test with these prespecified cut-off values was verified by prospective measurement of non-invasive and invasive haemoglobin pre-operatively in elective surgical patients. In 809 patients, this showed an estimated sensitivity (95%CI) of 98.9% (94.1-99.9%) in women and 96.4% (91.0-99.0%) in men. This saved invasive blood tests in 9% of female and 28% of male patients. In female patients, a lower non-invasive haemoglobin cut-off value (138 g.l^-1 ) would save 28% of invasive blood tests with a sensitivity of 95%. The target 99% sensitivity would be reached by non-invasive haemoglobin cut-off values of 152 g.l^-1 in female and 162 g.l^-1 in male patients, saving 3% and 9% of invasive blood tests, respectively. Bias and limits of agreement between non-invasive and laboratory haemoglobin levels were 2 and - 25 to 28 g.l^-1 , respectively. Patient and measurement characteristics did not influence the agreement between non-invasive and laboratory haemoglobin levels. Although sensitivity was very high, the index test using prespecified cut-off values just failed to reach the target sensitivity to detect true anaemia. Nevertheless, with respect to blood-sparing effects, the use of the index test in men may be clinically useful, while an index test with a lower cut-off (132 g.l^-1 ) could be more clinically appropriate in women.

Improving the diagnostic accuracy of a stratified screening strategy by identifying the optimal risk cutoff

BACKGROUND

The American Cancer Society (ACS) suggests using a stratified strategy for breast cancer screening. The strategy includes assessing risk of breast cancer, screening women at high risk with both MRI and mammography, and screening women at low risk with mammography alone. The ACS chose their cutoff for high risk using expert consensus.

METHODS

We propose instead an analytic approach that maximizes the diagnostic accuracy (AUC/ROC) of a risk-based stratified screening strategy in a population. The inputs are the joint distribution of screening test scores, and the odds of disease, for the given risk score. Using the approach for breast cancer screening, we estimated the optimal risk cutoff for two different risk models: the Breast Cancer Screening Consortium (BCSC) model and a hypothetical model with much better discriminatory accuracy. Data on mammography and MRI test score distributions were drawn from the Magnetic Resonance Imaging Screening Study Group.

RESULTS

A risk model with an excellent discriminatory accuracy (c-statistic [Formula: see text]) yielded a reasonable cutoff where only about 20% of women had dual screening. However, the BCSC risk model (c-statistic [Formula: see text]) lacked the discriminatory accuracy to differentiate between women who needed dual screening, and women who needed only mammography.

CONCLUSION

Our research provides a general approach to optimize the diagnostic accuracy of a stratified screening strategy in a population, and to assess whether risk models are sufficiently accurate to guide stratified screening. For breast cancer, most risk models lack enough discriminatory accuracy to make stratified screening a reasonable recommendation.

Enhancer Domains in Gastrointestinal Stromal Tumor Regulate KIT Expression and Are Targetable by BET Bromodomain Inhibition

Gastrointestinal stromal tumor (GIST) is a mesenchymal neoplasm characterized by activating mutations in the related receptor tyrosine kinases KIT and PDGFRA. GIST relies on expression of these unamplified receptor tyrosine kinase (RTK) genes through a large enhancer domain, resulting in high expression levels of the oncogene required for tumor growth. Although kinase inhibition is an effective therapy for many patients with GIST, disease progression from kinase-resistant mutations is common and no other effective classes of systemic therapy exist. In this study, we identify regulatory regions of the KIT enhancer essential for KIT gene expression and GIST cell viability. Given the dependence of GIST upon enhancer-driven expression of RTKs, we hypothesized that the enhancer domains could be therapeutically targeted by a BET bromodomain inhibitor (BBI). Treatment of GIST cells with BBIs led to cell-cycle arrest, apoptosis, and cell death, with unique sensitivity in GIST cells arising from attenuation of the KIT enhancer domain and reduced KIT gene expression. BBI treatment in KIT-dependent GIST cells produced genome-wide changes in the H3K27ac enhancer landscape and gene expression program, which was also seen with direct KIT inhibition using a tyrosine kinase inhibitor (TKI). Combination treatment with BBI and TKI led to superior cytotoxic effects in vitro and in vivo, with BBI preventing tumor growth in TKI-resistant xenografts. Resistance to select BBI in GIST was attributable to drug efflux pumps. These results define a therapeutic vulnerability and clinical strategy for targeting oncogenic kinase dependency in GIST. SIGNIFICANCE: Expression and activity of mutant KIT is essential for driving the majority of GIST neoplasms, which can be therapeutically targeted using BET bromodomain inhibitors.

The Influence of Number and Timing of Pregnancies on Breast Cancer Risk for Women With BRCA1 or BRCA2 Mutations

BACKGROUND

Full-term pregnancy (FTP) is associated with a reduced breast cancer (BC) risk over time, but women are at increased BC risk in the immediate years following an FTP. No large prospective studies, however, have examined whether the number and timing of pregnancies are associated with BC risk for BRCA1 and BRCA2 mutation carriers.

METHODS

Using weighted and time-varying Cox proportional hazards models, we investigated whether reproductive events are associated with BC risk for mutation carriers using a retrospective cohort (5707 BRCA1 and 3525 BRCA2 mutation carriers) and a prospective cohort (2276 BRCA1 and 1610 BRCA2 mutation carriers), separately for each cohort and the combined prospective and retrospective cohort.

RESULTS

For BRCA1 mutation carriers, there was no overall association with parity compared with nulliparity (combined hazard ratio [HRc] = 0.99, 95% confidence interval [CI] = 0.83 to 1.18). Relative to being uniparous, an increased number of FTPs was associated with decreased BC risk (HRc = 0.79, 95% CI = 0.69 to 0.91; HRc = 0.70, 95% CI = 0.59 to 0.82; HRc = 0.50, 95% CI = 0.40 to 0.63, for 2, 3, and ≥4 FTPs, respectively, P trend < .0001) and increasing duration of breastfeeding was associated with decreased BC risk (combined cohort P trend = .0003). Relative to being nulliparous, uniparous BRCA1 mutation carriers were at increased BC risk in the prospective analysis (prospective hazard ration [HRp] = 1.69, 95% CI = 1.09 to 2.62). For BRCA2 mutation carriers, being parous was associated with a 30% increase in BC risk (HRc = 1.33, 95% CI = 1.05 to 1.69), and there was no apparent decrease in risk associated with multiparity except for having at least 4 FTPs vs. 1 FTP (HRc = 0.72, 95% CI = 0.54 to 0.98).

CONCLUSIONS

These findings suggest differential associations with parity between BRCA1 and BRCA2 mutation carriers with higher risk for uniparous BRCA1 carriers and parous BRCA2 carriers.

The novel video-assisted intubating laryngeal mask Totaltrack compared to the intubating laryngeal mask Fastrach - a controlled randomized manikin study

BACKGROUND

The novel Totaltrack combines a supraglottic airway device with video laryngoscopic tracheal intubation. The intubation laryngeal mask Fastrach is an established device without visual control of intubation. We hypothesized that supraglottic ventilation success with Totaltrack would be similar to Fastrach, but intubation would be performed faster due to visual control of the procedure.

METHODS

Fifty-five anaesthesiologists were randomized into one of two study arms: Fastrach Totaltrack. After a standardized introduction, six consecutive attempts of supraglottic ventilation and intubation attempts with each of one of the devices were performed on an airway manikin. The combined primary outcome was: time to supraglottic ventilation and time to ventilation after intubation. Additionally, success rate and learning curves were evaluated.

RESULTS

Supraglottic time to ventilation was shorter when using the Fastrach compared to the Totaltrack (median: 7.8 s [confidence interval [CI]: 7.0-8.6 s] vs. 11 s [CI: 7.8-14.2 s], P < 0.001). Intubation was faster using the Fastrach compared to Totaltrack (median: 12.5 s, [CI: 10.1-14.9 s] vs. 23.3 s [CI: 21.5-25.1 s], P < 0.001). Success rate for supraglottic ventilation was comparable between Fastrach and Totaltrack (86-96%). Successful intubation via the device was 100% in Fastrach and ranged from 61% to 93% in Totaltrack, with a higher probability of successful intubation after four applications.

CONCLUSION

In this manikin-based study the novel Totaltrack did not prove superior to Fastrach despite a similar design. Video laryngoscopic control of supraglottic ventilation and endotracheal intubation was prolonged using the Totaltrack. Clinical trials are mandatory to evaluate the role of the Totaltrack in airway management.

Abstract P2-07-04: Risk of primary and contralateral breast cancer in BRCA1/2 mutation carriers previously affected with ovarian cancer

Introduction: BRCA1/2 mutation carriers are at increased risk of developing breast cancer (BC) and ovarian cancer (OC). However, for BRCA1/2 mutation carriers previously affected with OC, primary BC (PBC) and contralateral BC (CBC) risks might be lowered due to OC treatment, but data hereon are limited. Accurate BC risk estimates are essential for counseling and optimal decision making on BC surveillance and risk-reducing mastectomy (RRM) after diagnosis of BRCA1/2-associated OC.

Methods: From the national HEBON cohort study, we selected female BRCA1/2 mutation carriers born from 1940 and at risk of PBC (n=2019; 1194 BRCA1, 825 BRCA2) or at risk of CBC (n=1276; 839 BRCA1, 437 BRCA2). Eligibility criteria for the PBC risk analyses included no history of PBC and both breasts in situ at DNA testing. For the CBC risk analyses, CBC before DNA testing was not allowed and the contralateral breast had to be unaffected at DNA testing. To estimate the association between OC and BC risk, we used the Fine and Gray regression model, with OC as a time-dependent variable and death as competing risk event. The observation started at the age of DNA testing, age 35, or – for the CBC risk analyses – age at PBC diagnosis, whichever came last. Censoring events were RRM, study closing date (i.e. 2014-12-31), and – for the CBC risk analyses – ipsilateral BC recurrence. All analyses were performed separately for BRCA1 and BRCA2 mutation carriers.

Results: For the PBC analyses, we selected 236 BRCA1/2 mutation carriers with OC and 1783 BRCA1/2 mutation carriers without OC (median age at start study 53 and 41 years, respectively). During a mean follow-up (FU) of 5.2 years, 15 (6%) OC patients developed PBC after OC, while PBC was diagnosed in 262 (15%) women without OC. OC diagnosis was associated with a lower PBC risk in BRCA1 mutation carriers (HR, 0.27; 95% CI, 0.14–0.53) but not in BRCA2 mutation carriers (HR, 0.88; 95% CI, 0.34–2.27). The cumulative PBC incidence at age 70 in BRCA1 mutation carriers was 25% for OC patients and 66% for women without OC, and in BRCA2 mutation carriers 49% for OC patients and 53% for women without OC.

For the CBC analyses, we selected 99 BRCA1/2 mutation carriers affected with PBC and OC, and 1177 BRCA1/2-associated PBC patients without OC (median age at start study 54 and 46 years, respectively). During a mean FU of 3.5 years, 8 (8%) PBC/OC patients developed CBC after OC, while CBC was diagnosed in 131 (11%) PBC patients without OC. In BRCA1 mutation carriers, OC diagnosis was non-significantly associated with a lower CBC risk (HR, 0.44; 95% CI, 0.19–1.03). For BRCA2 mutation carriers the HR was 1.65 (95% CI, 0.34–8.04). The cumulative CBC incidence at age 70 in BRCA1 mutation carriers was 40% for OC patients and 68% for patients without OC; for BRCA2 mutation carriers the number of CBCs was too small to obtain meaningful estimates.

Conclusion:­ For BRCA1 mutation carriers affected with OC the risk of developing subsequent BC is lower than for BRCA1 mutation carriers without OC. Our data suggest that the current BC prevention strategies should be reconsidered for OC patients carrying a BRCA1 mutation, possibly including less intensive BC surveillance, and RRM being indicated only for a subgroup of OC patients.

Citation Format: Heemskerk-Gerritsen BAM, Hooning MJ, van Doorn HC, Collée MJ, Koppert LB, Jager A, van den Ouweland AMW, Netherlands H, Seynaeve C, Kriege M. Risk of primary and contralateral breast cancer in BRCA1/2 mutation carriers previously affected with ovarian cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-07-04.

Association of breast cancer risk in BRCA1 and BRCA2 mutation carriers with genetic variants showing differential allelic expression: identification of a modifier of breast cancer risk at locus 11q22.3

PURPOSE

Cis-acting regulatory SNPs resulting in differential allelic expression (DAE) may, in part, explain the underlying phenotypic variation associated with many complex diseases. To investigate whether common variants associated with DAE were involved in breast cancer susceptibility among BRCA1 and BRCA2 mutation carriers, a list of 175 genes was developed based of their involvement in cancer-related pathways.

METHODS

Using data from a genome-wide map of SNPs associated with allelic expression, we assessed the association of ~320 SNPs located in the vicinity of these genes with breast and ovarian cancer risks in 15,252 BRCA1 and 8211 BRCA2 mutation carriers ascertained from 54 studies participating in the Consortium of Investigators of Modifiers of BRCA1/2.

RESULTS

We identified a region on 11q22.3 that is significantly associated with breast cancer risk in BRCA1 mutation carriers (most significant SNP rs228595 p = 7 × 10-6). This association was absent in BRCA2 carriers (p = 0.57). The 11q22.3 region notably encompasses genes such as ACAT1, NPAT, and ATM. Expression quantitative trait loci associations were observed in both normal breast and tumors across this region, namely for ACAT1, ATM, and other genes. In silico analysis revealed some overlap between top risk-associated SNPs and relevant biological features in mammary cell data, which suggests potential functional significance.

CONCLUSION

We identified 11q22.3 as a new modifier locus in BRCA1 carriers. Replication in larger studies using estrogen receptor (ER)-negative or triple-negative (i.e., ER-, progesterone receptor-, and HER2-negative) cases could therefore be helpful to confirm the association of this locus with breast cancer risk.

Fine scale mapping of the 17q22 breast cancer locus using dense SNPs, genotyped within the Collaborative Oncological Gene-Environment Study (COGs)

Genome-wide association studies have found SNPs at 17q22 to be associated with breast cancer risk. To identify potential causal variants related to breast cancer risk, we performed a high resolution fine-mapping analysis that involved genotyping 517 SNPs using a custom Illumina iSelect array (iCOGS) followed by imputation of genotypes for 3,134 SNPs in more than 89,000 participants of European ancestry from the Breast Cancer Association Consortium (BCAC). We identified 28 highly correlated common variants, in a 53 Kb region spanning two introns of the STXBP4 gene, that are strong candidates for driving breast cancer risk (lead SNP rs2787486 (OR = 0.92; CI 0.90-0.94; P = 8.96 × 10(-15))) and are correlated with two previously reported risk-associated variants at this locus, SNPs rs6504950 (OR = 0.94, P = 2.04 × 10(-09), r(2) = 0.73 with lead SNP) and rs1156287 (OR = 0.93, P = 3.41 × 10(-11), r(2) = 0.83 with lead SNP). Analyses indicate only one causal SNP in the region and several enhancer elements targeting STXBP4 are located within the 53 kb association signal. Expression studies in breast tumor tissues found SNP rs2787486 to be associated with increased STXBP4 expression, suggesting this may be a target gene of this locus.

Timing of risk reducing mastectomy in breast cancer patients carrying a BRCA1/2 mutation: retrospective data from the Dutch HEBON study

It is expected that rapid genetic counseling and testing (RGCT) will lead to increasing numbers of breast cancer (BC) patients knowing their BRCA1/2 carrier status before primary surgery. Considering the potential impact of knowing one’s status on uptake and timing of risk-reducing contralateral mastectomy (RRCM), we aimed to evaluate trends over time in RRCM, and differences between carriers identified either before (predictively) or after (diagnostically) diagnosis. We collected data from female BRCA1/2 mutation carriers diagnosed with BC between 1995 and 2009 from four Dutch university hospitals. We compared the timing of genetic testing and RRCM in relation to diagnosis in 1995–2000 versus 2001–2009 for all patients, and predictively and diagnostically tested patients separately. Of 287 patients, 219 (76 %) had a diagnostic BRCA1/2 test. In this cohort, the median time from diagnosis to DNA testing decreased from 28 months for those diagnosed between 1995 and 2000 to 14 months for those diagnosed between 2001 and 2009 (p < 0.001). Similarly, over time women in this cohort underwent RRCM sooner after diagnosis (median of 77 vs. 27 months, p = 0.05). Predictively tested women who subsequently developed BC underwent an immediate RRCM significantly more often than women who had a diagnostic test (21/61, 34 %, vs. 13/170, 7.6 %, p < 0.001). Knowledge of carrying a BRCA1/2 mutation when diagnosed with BC influenced decisions concerning primary surgery. Additionally, in more recent years, women who had not undergone predictive testing were more likely to undergo diagnostic DNA testing and RRCM sooner after diagnosis. This suggests the need for RGCT to guide treatment decisions.

Association of genetic susceptibility variants for type 2 diabetes with breast cancer risk in women of European ancestry

PURPOSE

Type 2 diabetes (T2D) has been reported to be associated with an elevated risk of breast cancer. It is unclear, however, whether this association is due to shared genetic factors.

METHODS

We constructed a genetic risk score (GRS) using risk variants from 33 known independent T2D susceptibility loci and evaluated its relation to breast cancer risk using the data from two consortia, including 62,328 breast cancer patients and 83,817 controls of European ancestry. Unconditional logistic regression models were used to derive adjusted odds ratios (ORs) and 95 % confidence intervals (CIs) to measure the association of breast cancer risk with T2D GRS or T2D-associated genetic risk variants. Meta-analyses were conducted to obtain summary ORs across all studies.

RESULTS

The T2D GRS was not found to be associated with breast cancer risk, overall, by menopausal status, or for estrogen receptor positive or negative breast cancer. Three T2D associated risk variants were individually associated with breast cancer risk after adjustment for multiple comparisons using the Bonferroni method (at p < 0.001), rs9939609 (FTO) (OR 0.94, 95 % CI = 0.92-0.95, p = 4.13E-13), rs7903146 (TCF7L2) (OR 1.04, 95 % CI = 1.02-1.06, p = 1.26E-05), and rs8042680 (PRC1) (OR 0.97, 95 % CI = 0.95-0.99, p = 8.05E-04).

CONCLUSIONS

We have shown that several genetic risk variants were associated with the risk of both T2D and breast cancer. However, overall genetic susceptibility to T2D may not be related to breast cancer risk.

Fine-mapping identifies two additional breast cancer susceptibility loci at 9q31.2

We recently identified a novel susceptibility variant, rs865686, for estrogen-receptor positive breast cancer at 9q31.2. Here, we report a fine-mapping analysis of the 9q31.2 susceptibility locus using 43 160 cases and 42 600 controls of European ancestry ascertained from 52 studies and a further 5795 cases and 6624 controls of Asian ancestry from nine studies. Single nucleotide polymorphism (SNP) rs676256 was most strongly associated with risk in Europeans (odds ratios [OR] = 0.90 [0.88-0.92]; P-value = 1.58 × 10(-25)). This SNP is one of a cluster of highly correlated variants, including rs865686, that spans ∼14.5 kb. We identified two additional independent association signals demarcated by SNPs rs10816625 (OR = 1.12 [1.08-1.17]; P-value = 7.89 × 10(-09)) and rs13294895 (OR = 1.09 [1.06-1.12]; P-value = 2.97 × 10(-11)). SNP rs10816625, but not rs13294895, was also associated with risk of breast cancer in Asian individuals (OR = 1.12 [1.06-1.18]; P-value = 2.77 × 10(-05)). Functional genomic annotation using data derived from breast cancer cell-line models indicates that these SNPs localise to putative enhancer elements that bind known drivers of hormone-dependent breast cancer, including ER-α, FOXA1 and GATA-3. In vitro analyses indicate that rs10816625 and rs13294895 have allele-specific effects on enhancer activity and suggest chromatin interactions with the KLF4 gene locus. These results demonstrate the power of dense genotyping in large studies to identify independent susceptibility variants. Analysis of associations using subjects with different ancestry, combined with bioinformatic and genomic characterisation, can provide strong evidence for the likely causative alleles and their functional basis.

Sensitivity to systemic therapy for metastatic breast cancer in CHEK2 1100delC mutation carriers

PURPOSE

The role of CHEK2 in DNA repair by homologous recombination suggests that CHEK2-associated breast cancer (BC) patients might be more sensitive to chemotherapy inducing double-strand DNA breaks, but results hereon are lacking. We compared the sensitivity to first-line chemotherapy and endocrine therapy between CHEK2 1100delC and non-CHEK2 metastatic breast cancer (MBC) patients.

METHODS

Sixty-two CHEK2 1100delC MBC patients were selected from three cohorts genotyped for CHEK2 1100delC (one non-BRCA1/2 cohort and two sporadic cohorts). Controls were 62 non-CHEK2 MBC patients, matched for age at and year of primary BC diagnosis, and year of metastatic disease. Objective response rate (complete and partial response) to, and progression-free survival (PFS) and overall survival (OS) after start of first-line chemotherapy and endocrine therapy were compared between CHEK2 and non-CHEK2 patients.

RESULTS

Median age at BC diagnosis was 46 and 51 years at MBC diagnosis. First-line chemotherapy consisted of anthracycline-based chemotherapy (n = 73), taxanes (n = 16), CMF(-like) chemotherapy (n = 33) and taxane/anthracycline regimens (n = 2). CHEK2 and non-CHEK2 patients had a comparable objective response rate (44 vs. 52 %). Also, PFS and OS after start of chemotherapy were comparable between both patient groups (hazard ratio 0.91; 95 % confidence interval 0.63-1.30 and 1.03; 95 % CI 0.71-1.49, respectively). Thirty-six CHEK2 and 32 non-CHEK2 patients received first-line endocrine therapy (mainly tamoxifen) for MBC. No significant differences were observed in objective response rate to, and PFS and OS after start of endocrine therapy.

CONCLUSION

No differential efficacy of chemotherapy and endocrine therapy given for MBC was observed in CHEK2 versus non-CHEK2 patients.

Inherited variants in the inner centromere protein (INCENP) gene of the chromosomal passenger complex contribute to the susceptibility of ER-negative breast cancer

The chromosomal passenger complex (CPC) plays a pivotal role in the regulation of cell division. Therefore, inherited CPC variability could influence tumor development. The present candidate gene approach investigates the relationship between single nucleotide polymorphisms (SNPs) in genes encoding key CPC components and breast cancer risk. Fifteen SNPs in four CPC genes (INCENP, AURKB, BIRC5 and CDCA8) were genotyped in 88 911 European women from 39 case-control studies of the Breast Cancer Association Consortium. Possible associations were investigated in fixed-effects meta-analyses. The synonymous SNP rs1675126 in exon 7 of INCENP was associated with overall breast cancer risk [per A allele odds ratio (OR) 0.95, 95% confidence interval (CI) 0.92-0.98, P = 0.007] and particularly with estrogen receptor (ER)-negative breast tumors (per A allele OR 0.89, 95% CI 0.83-0.95, P = 0.0005). SNPs not directly genotyped were imputed based on 1000 Genomes. The SNPs rs1047739 in the 3' untranslated region and rs144045115 downstream of INCENP showed the strongest association signals for overall (per T allele OR 1.03, 95% CI 1.00-1.06, P = 0.0009) and ER-negative breast cancer risk (per A allele OR 1.06, 95% CI 1.02-1.10, P = 0.0002). Two genotyped SNPs in BIRC5 were associated with familial breast cancer risk (top SNP rs2071214: per G allele OR 1.12, 95% CI 1.04-1.21, P = 0.002). The data suggest that INCENP in the CPC pathway contributes to ER-negative breast cancer susceptibility in the European population. In spite of a modest contribution of CPC-inherited variants to the total burden of sporadic and familial breast cancer, their potential as novel targets for breast cancer treatment should be further investigated.

Common non-synonymous SNPs associated with breast cancer susceptibility: findings from the Breast Cancer Association Consortium

Candidate variant association studies have been largely unsuccessful in identifying common breast cancer susceptibility variants, although most studies have been underpowered to detect associations of a realistic magnitude. We assessed 41 common non-synonymous single-nucleotide polymorphisms (nsSNPs) for which evidence of association with breast cancer risk had been previously reported. Case-control data were combined from 38 studies of white European women (46 450 cases and 42 600 controls) and analyzed using unconditional logistic regression. Strong evidence of association was observed for three nsSNPs: ATXN7-K264R at 3p21 [rs1053338, per allele OR = 1.07, 95% confidence interval (CI) = 1.04-1.10, P = 2.9 × 10(-6)], AKAP9-M463I at 7q21 (rs6964587, OR = 1.05, 95% CI = 1.03-1.07, P = 1.7 × 10(-6)) and NEK10-L513S at 3p24 (rs10510592, OR = 1.10, 95% CI = 1.07-1.12, P = 5.1 × 10(-17)). The first two associations reached genome-wide statistical significance in a combined analysis of available data, including independent data from nine genome-wide association studies (GWASs): for ATXN7-K264R, OR = 1.07 (95% CI = 1.05-1.10, P = 1.0 × 10(-8)); for AKAP9-M463I, OR = 1.05 (95% CI = 1.04-1.07, P = 2.0 × 10(-10)). Further analysis of other common variants in these two regions suggested that intronic SNPs nearby are more strongly associated with disease risk. We have thus identified a novel susceptibility locus at 3p21, and confirmed previous suggestive evidence that rs6964587 at 7q21 is associated with risk. The third locus, rs10510592, is located in an established breast cancer susceptibility region; the association was substantially attenuated after adjustment for the known GWAS hit. Thus, each of the associated nsSNPs is likely to be a marker for another, non-coding, variant causally related to breast cancer risk. Further fine-mapping and functional studies are required to identify the underlying risk-modifying variants and the genes through which they act.

Genetic variation in mitotic regulatory pathway genes is associated with breast tumor grade

Mitotic index is an important component of histologic grade and has an etiologic role in breast tumorigenesis. Several small candidate gene studies have reported associations between variation in mitotic genes and breast cancer risk. We measured associations between 2156 single nucleotide polymorphisms (SNPs) from 194 mitotic genes and breast cancer risk, overall and by histologic grade, in the Breast Cancer Association Consortium (BCAC) iCOGS study (n = 39 067 cases; n = 42 106 controls). SNPs in TACC2 [rs17550038: odds ratio (OR) = 1.24, 95% confidence interval (CI) 1.16-1.33, P = 4.2 × 10(-10)) and EIF3H (rs799890: OR = 1.07, 95% CI 1.04-1.11, P = 8.7 × 10(-6)) were significantly associated with risk of low-grade breast cancer. The TACC2 signal was retained (rs17550038: OR = 1.15, 95% CI 1.07-1.23, P = 7.9 × 10(-5)) after adjustment for breast cancer risk SNPs in the nearby FGFR2 gene, suggesting that TACC2 is a novel, independent genome-wide significant genetic risk locus for low-grade breast cancer. While no SNPs were individually associated with high-grade disease, a pathway-level gene set analysis showed that variation across the 194 mitotic genes was associated with high-grade breast cancer risk (P = 2.1 × 10(-3)). These observations will provide insight into the contribution of mitotic defects to histological grade and the etiology of breast cancer.

2q36.3 is associated with prognosis for oestrogen receptor-negative breast cancer patients treated with chemotherapy

Large population-based registry studies have shown that breast cancer prognosis is inherited. Here we analyse single-nucleotide polymorphisms (SNPs) of genes implicated in human immunology and inflammation as candidates for prognostic markers of breast cancer survival involving 1,804 oestrogen receptor (ER)-negative patients treated with chemotherapy (279 events) from 14 European studies in a prior large-scale genotyping experiment, which is part of the Collaborative Oncological Gene-environment Study (COGS) initiative. We carry out replication using Asian COGS samples (n=522, 53 events) and the Prospective Study of Outcomes in Sporadic versus Hereditary breast cancer (POSH) study (n=315, 108 events). Rs4458204_A near CCL20 (2q36.3) is found to be associated with breast cancer-specific death at a genome-wide significant level (n=2,641, 440 events, combined allelic hazard ratio (HR)=1.81 (1.49-2.19); P for trend=1.90 × 10(-9)). Such survival-associated variants can represent ideal targets for tailored therapeutics, and may also enhance our current prognostic prediction capabilities.

Genetic predisposition to in situ and invasive lobular carcinoma of the breast

Invasive lobular breast cancer (ILC) accounts for 10-15% of all invasive breast carcinomas. It is generally ER positive (ER+) and often associated with lobular carcinoma in situ (LCIS). Genome-wide association studies have identified more than 70 common polymorphisms that predispose to breast cancer, but these studies included predominantly ductal (IDC) carcinomas. To identify novel common polymorphisms that predispose to ILC and LCIS, we pooled data from 6,023 cases (5,622 ILC, 401 pure LCIS) and 34,271 controls from 36 studies genotyped using the iCOGS chip. Six novel SNPs most strongly associated with ILC/LCIS in the pooled analysis were genotyped in a further 516 lobular cases (482 ILC, 36 LCIS) and 1,467 controls. These analyses identified a lobular-specific SNP at 7q34 (rs11977670, OR (95%CI) for ILC = 1.13 (1.09-1.18), P = 6.0 × 10(-10); P-het for ILC vs IDC ER+ tumors = 1.8 × 10(-4)). Of the 75 known breast cancer polymorphisms that were genotyped, 56 were associated with ILC and 15 with LCIS at P<0.05. Two SNPs showed significantly stronger associations for ILC than LCIS (rs2981579/10q26/FGFR2, P-het = 0.04 and rs889312/5q11/MAP3K1, P-het = 0.03); and two showed stronger associations for LCIS than ILC (rs6678914/1q32/LGR6, P-het = 0.001 and rs1752911/6q14, P-het = 0.04). In addition, seven of the 75 known loci showed significant differences between ER+ tumors with IDC and ILC histology, three of these showing stronger associations for ILC (rs11249433/1p11, rs2981579/10q26/FGFR2 and rs10995190/10q21/ZNF365) and four associated only with IDC (5p12/rs10941679; rs2588809/14q24/RAD51L1, rs6472903/8q21 and rs1550623/2q31/CDCA7). In conclusion, we have identified one novel lobular breast cancer specific predisposition polymorphism at 7q34, and shown for the first time that common breast cancer polymorphisms predispose to LCIS. We have shown that many of the ER+ breast cancer predisposition loci also predispose to ILC, although there is some heterogeneity between ER+ lobular and ER+ IDC tumors. These data provide evidence for overlapping, but distinct etiological pathways within ER+ breast cancer between morphological subtypes.

FGF receptor genes and breast cancer susceptibility: results from the Breast Cancer Association Consortium

BACKGROUND

Breast cancer is one of the most common malignancies in women. Genome-wide association studies have identified FGFR2 as a breast cancer susceptibility gene. Common variation in other fibroblast growth factor (FGF) receptors might also modify risk. We tested this hypothesis by studying genotyped single-nucleotide polymorphisms (SNPs) and imputed SNPs in FGFR1, FGFR3, FGFR4 and FGFRL1 in the Breast Cancer Association Consortium.

METHODS

Data were combined from 49 studies, including 53 835 cases and 50 156 controls, of which 89 050 (46 450 cases and 42 600 controls) were of European ancestry, 12 893 (6269 cases and 6624 controls) of Asian and 2048 (1116 cases and 932 controls) of African ancestry. Associations with risk of breast cancer, overall and by disease sub-type, were assessed using unconditional logistic regression.

RESULTS

Little evidence of association with breast cancer risk was observed for SNPs in the FGF receptor genes. The strongest evidence in European women was for rs743682 in FGFR3; the estimated per-allele odds ratio was 1.05 (95% confidence interval=1.02-1.09, P=0.0020), which is substantially lower than that observed for SNPs in FGFR2.

CONCLUSION

Our results suggest that common variants in the other FGF receptors are not associated with risk of breast cancer to the degree observed for FGFR2.

Multiple independent variants at the TERT locus are associated with telomere length and risks of breast and ovarian cancer

TERT-locus SNPs and leukocyte telomere measures are reportedly associated with risks of multiple cancers. Using the Illumina custom genotyping array iCOGs, we analyzed ∼480 SNPs at the TERT locus in breast (n = 103,991), ovarian (n = 39,774) and BRCA1 mutation carrier (n = 11,705) cancer cases and controls. Leukocyte telomere measurements were also available for 53,724 participants. Most associations cluster into three independent peaks. The minor allele at the peak 1 SNP rs2736108 associates with longer telomeres (P = 5.8 × 10(-7)), lower risks for estrogen receptor (ER)-negative (P = 1.0 × 10(-8)) and BRCA1 mutation carrier (P = 1.1 × 10(-5)) breast cancers and altered promoter assay signal. The minor allele at the peak 2 SNP rs7705526 associates with longer telomeres (P = 2.3 × 10(-14)), higher risk of low-malignant-potential ovarian cancer (P = 1.3 × 10(-15)) and greater promoter activity. The minor alleles at the peak 3 SNPs rs10069690 and rs2242652 increase ER-negative (P = 1.2 × 10(-12)) and BRCA1 mutation carrier (P = 1.6 × 10(-14)) breast and invasive ovarian (P = 1.3 × 10(-11)) cancer risks but not via altered telomere length. The cancer risk alleles of rs2242652 and rs10069690, respectively, increase silencing and generate a truncated TERT splice variant.

Genome-wide association studies identify four ER negative-specific breast cancer risk loci

Estrogen receptor (ER)-negative tumors represent 20-30% of all breast cancers, with a higher proportion occurring in younger women and women of African ancestry. The etiology and clinical behavior of ER-negative tumors are different from those of tumors expressing ER (ER positive), including differences in genetic predisposition. To identify susceptibility loci specific to ER-negative disease, we combined in a meta-analysis 3 genome-wide association studies of 4,193 ER-negative breast cancer cases and 35,194 controls with a series of 40 follow-up studies (6,514 cases and 41,455 controls), genotyped using a custom Illumina array, iCOGS, developed by the Collaborative Oncological Gene-environment Study (COGS). SNPs at four loci, 1q32.1 (MDM4, P = 2.1 × 10(-12) and LGR6, P = 1.4 × 10(-8)), 2p24.1 (P = 4.6 × 10(-8)) and 16q12.2 (FTO, P = 4.0 × 10(-8)), were associated with ER-negative but not ER-positive breast cancer (P > 0.05). These findings provide further evidence for distinct etiological pathways associated with invasive ER-positive and ER-negative breast cancers.

Outcome of BRCA1- compared with BRCA2-associated ovarian cancer: a nationwide study in the Netherlands

BACKGROUND

Recent studies suggested an improved overall survival (OS) for BRCA2- versus BRCA1-associated epithelial ovarian cancer (EOC), whereas the impact of chemotherapy is not yet clear. In a nationwide cohort, we examined the results of primary treatment, progression-free survival (PFS), treatment-free interval (TFI), and OS of BRCA1 versus BRCA2 EOC patients.

METHODS

Two hundred and forty-five BRCA1- and 99 BRCA2-associated EOC patients were identified through all Dutch university hospitals. Analyses were carried out with the Pearson's Chi-square test, Kaplan-Meier, and Cox regression methods.

RESULTS

BRCA1 patients were younger at EOC diagnosis than BRCA2 patients (51 versus 55 years; P < 0.001), without differences regarding histology, tumor grade, and International Federation of Gynecology and Obstetrics (FIGO) stage. Complete response rates after primary treatment, including chemotherapy, did not differ between BRCA1 (86%) and BRCA2 patients (90%). BRCA1 versus BRCA2 patients had a shorter PFS (median 2.2 versus 3.9 years, respectively; P = 0.006), TFI (median 1.7 versus 2.8 years; P = 0.009), and OS (median 6.0 versus 9.7 years; P = 0.04). Differences could not be explained by age at diagnosis, FIGO stage or type of treatment.

CONCLUSIONS

PFS and OS were substantially longer in BRCA2- than in BRCA1-associated EOC patients. While response rates after primary treatment were similarly high in both groups, TFI, as surrogate for chemosensitivity, was significantly longer in BRCA2 patients.

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

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.

CHEK2*1100delC heterozygosity in women with breast cancer associated with early death, breast cancer-specific death, and increased risk of a second breast cancer

PURPOSE

We tested the hypotheses that CHEK2*1100delC heterozygosity is associated with increased risk of early death, breast cancer-specific death, and risk of a second breast cancer in women with a first breast cancer.

PATIENTS AND METHODS

From 22 studies participating in the Breast Cancer Association Consortium, 25,571 white women with invasive breast cancer were genotyped for CHEK2*1100delC and observed for up to 20 years (median, 6.6 years). We examined risk of early death and breast cancer-specific death by estrogen receptor status and risk of a second breast cancer after a first breast cancer in prospective studies.

RESULTS

CHEK2*1100delC heterozygosity was found in 459 patients (1.8%). In women with estrogen receptor-positive breast cancer, multifactorially adjusted hazard ratios for heterozygotes versus noncarriers were 1.43 (95% CI, 1.12 to 1.82; log-rank P = .004) for early death and 1.63 (95% CI, 1.24 to 2.15; log-rank P < .001) for breast cancer-specific death. In all women, hazard ratio for a second breast cancer was 2.77 (95% CI, 2.00 to 3.83; log-rank P < .001) increasing to 3.52 (95% CI, 2.35 to 5.27; log-rank P < .001) in women with estrogen receptor-positive first breast cancer only.

CONCLUSION

Among women with estrogen receptor-positive breast cancer, CHEK2*1100delC heterozygosity was associated with a 1.4-fold risk of early death, a 1.6-fold risk of breast cancer-specific death, and a 3.5-fold risk of a second breast cancer. This is one of the few examples of a genetic factor that influences long-term prognosis being documented in an extensive series of women with breast cancer.

The role of genetic breast cancer susceptibility variants as prognostic factors

Recent genome-wide association studies identified 11 single nucleotide polymorphisms (SNPs) associated with breast cancer (BC) risk. We investigated these and 62 other SNPs for their prognostic relevance. Confirmed BC risk SNPs rs17468277 (CASP8), rs1982073 (TGFB1), rs2981582 (FGFR2), rs13281615 (8q24), rs3817198 (LSP1), rs889312 (MAP3K1), rs3803662 (TOX3), rs13387042 (2q35), rs4973768 (SLC4A7), rs6504950 (COX11) and rs10941679 (5p12) were genotyped for 25 853 BC patients with the available follow-up; 62 other SNPs, which have been suggested as BC risk SNPs by a GWAS or as candidate SNPs from individual studies, were genotyped for replication purposes in subsets of these patients. Cox proportional hazard models were used to test the association of these SNPs with overall survival (OS) and BC-specific survival (BCS). For the confirmed loci, we performed an accessory analysis of publicly available gene expression data and the prognosis in a different patient group. One of the 11 SNPs, rs3803662 (TOX3) and none of the 62 candidate/GWAS SNPs were associated with OS and/or BCS at P<0.01. The genotypic-specific survival for rs3803662 suggested a recessive mode of action [hazard ratio (HR) of rare homozygous carriers=1.21; 95% CI: 1.09-1.35, P=0.0002 and HR=1.29; 95% CI: 1.12-1.47, P=0.0003 for OS and BCS, respectively]. This association was seen similarly in all analyzed tumor subgroups defined by nodal status, tumor size, grade and estrogen receptor. Breast tumor expression of these genes was not associated with prognosis. With the exception of rs3803662 (TOX3), there was no evidence that any of the SNPs associated with BC susceptibility were associated with the BC survival. Survival may be influenced by a distinct set of germline variants from those influencing susceptibility.

Ovarian cancer susceptibility alleles and risk of ovarian cancer in BRCA1 and BRCA2 mutation carriers

Germline mutations in BRCA1 and BRCA2 are associated with increased risks of breast and ovarian cancer. A genome-wide association study (GWAS) identified six alleles associated with risk of ovarian cancer for women in the general population. We evaluated four of these loci as potential modifiers of ovarian cancer risk for BRCA1 and BRCA2 mutation carriers. Four single-nucleotide polymorphisms (SNPs), rs10088218 (at 8q24), rs2665390 (at 3q25), rs717852 (at 2q31), and rs9303542 (at 17q21), were genotyped in 12,599 BRCA1 and 7,132 BRCA2 carriers, including 2,678 ovarian cancer cases. Associations were evaluated within a retrospective cohort approach. All four loci were associated with ovarian cancer risk in BRCA2 carriers; rs10088218 per-allele hazard ratio (HR) = 0.81 (95% CI: 0.67-0.98) P-trend = 0.033, rs2665390 HR = 1.48 (95% CI: 1.21-1.83) P-trend = 1.8 × 10(-4), rs717852 HR = 1.25 (95% CI: 1.10-1.42) P-trend = 6.6 × 10(-4), rs9303542 HR = 1.16 (95% CI: 1.02-1.33) P-trend = 0.026. Two loci were associated with ovarian cancer risk in BRCA1 carriers; rs10088218 per-allele HR = 0.89 (95% CI: 0.81-0.99) P-trend = 0.029, rs2665390 HR = 1.25 (95% CI: 1.10-1.42) P-trend = 6.1 × 10(-4). The HR estimates for the remaining loci were consistent with odds ratio estimates for the general population. The identification of multiple loci modifying ovarian cancer risk may be useful for counseling women with BRCA1 and BRCA2 mutations regarding their risk of ovarian cancer.

Common variants at 12p11, 12q24, 9p21, 9q31.2 and in ZNF365 are associated with breast cancer risk for BRCA1 and/or BRCA2 mutation carriers

INTRODUCTION

Several common alleles have been shown to be associated with breast and/or ovarian cancer risk for BRCA1 and BRCA2 mutation carriers. Recent genome-wide association studies of breast cancer have identified eight additional breast cancer susceptibility loci: rs1011970 (9p21, CDKN2A/B), rs10995190 (ZNF365), rs704010 (ZMIZ1), rs2380205 (10p15), rs614367 (11q13), rs1292011 (12q24), rs10771399 (12p11 near PTHLH) and rs865686 (9q31.2).

METHODS

To evaluate whether these single nucleotide polymorphisms (SNPs) are associated with breast cancer risk for BRCA1 and BRCA2 carriers, we genotyped these SNPs in 12,599 BRCA1 and 7,132 BRCA2 mutation carriers and analysed the associations with breast cancer risk within a retrospective likelihood framework.

RESULTS

Only SNP rs10771399 near PTHLH was associated with breast cancer risk for BRCA1 mutation carriers (per-allele hazard ratio (HR) = 0.87, 95% CI: 0.81 to 0.94, P-trend = 3 × 10-4). The association was restricted to mutations proven or predicted to lead to absence of protein expression (HR = 0.82, 95% CI: 0.74 to 0.90, P-trend = 3.1 × 10-5, P-difference = 0.03). Four SNPs were associated with the risk of breast cancer for BRCA2 mutation carriers: rs10995190, P-trend = 0.015; rs1011970, P-trend = 0.048; rs865686, 2df-P = 0.007; rs1292011 2df-P = 0.03. rs10771399 (PTHLH) was predominantly associated with estrogen receptor (ER)-negative breast cancer for BRCA1 mutation carriers (HR = 0.81, 95% CI: 0.74 to 0.90, P-trend = 4 × 10-5) and there was marginal evidence of association with ER-negative breast cancer for BRCA2 mutation carriers (HR = 0.78, 95% CI: 0.62 to 1.00, P-trend = 0.049).

CONCLUSIONS

The present findings, in combination with previously identified modifiers of risk, will ultimately lead to more accurate risk prediction and an improved understanding of the disease etiology in BRCA1 and BRCA2 mutation carriers.

Pathology of breast and ovarian cancers among BRCA1 and BRCA2 mutation carriers: results from the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA)

BACKGROUND

Previously, small studies have found that BRCA1 and BRCA2 breast tumors differ in their pathology. Analysis of larger datasets of mutation carriers should allow further tumor characterization.

METHODS

We used data from 4,325 BRCA1 and 2,568 BRCA2 mutation carriers to analyze the pathology of invasive breast, ovarian, and contralateral breast cancers.

RESULTS

There was strong evidence that the proportion of estrogen receptor (ER)-negative breast tumors decreased with age at diagnosis among BRCA1 (P-trend = 1.2 × 10(-5)), but increased with age at diagnosis among BRCA2, carriers (P-trend = 6.8 × 10(-6)). The proportion of triple-negative tumors decreased with age at diagnosis in BRCA1 carriers but increased with age at diagnosis of BRCA2 carriers. In both BRCA1 and BRCA2 carriers, ER-negative tumors were of higher histologic grade than ER-positive tumors (grade 3 vs. grade 1; P = 1.2 × 10(-13) for BRCA1 and P = 0.001 for BRCA2). ER and progesterone receptor (PR) expression were independently associated with mutation carrier status [ER-positive odds ratio (OR) for BRCA2 = 9.4, 95% CI: 7.0-12.6 and PR-positive OR = 1.7, 95% CI: 1.3-2.3, under joint analysis]. Lobular tumors were more likely to be BRCA2-related (OR for BRCA2 = 3.3, 95% CI: 2.4-4.4; P = 4.4 × 10(-14)), and medullary tumors BRCA1-related (OR for BRCA2 = 0.25, 95% CI: 0.18-0.35; P = 2.3 × 10(-15)). ER-status of the first breast cancer was predictive of ER-status of asynchronous contralateral breast cancer (P = 0.0004 for BRCA1; P = 0.002 for BRCA2). There were no significant differences in ovarian cancer morphology between BRCA1 and BRCA2 carriers (serous: 67%; mucinous: 1%; endometrioid: 12%; clear-cell: 2%). CONCLUSIONS/IMPACT: Pathologic characteristics of BRCA1 and BRCA2 tumors may be useful for improving risk-prediction algorithms and informing clinical strategies for screening and prophylaxis.

P4-11-04: Risk of Primary (PBC) and Contralateral Breast Cancer (CBC) after Ovarian Cancer (OC) in BRCA1 and BRCA2 Mutation Carriers; Implications for Surveillance and Risk Reducing Mastectomy

Background In view of the increased risk of developing breast (BC) cancer, BRCA mutation carriers are offered intensive surveillance or risk reducing mastectomy (RRM) and/or salpingo-ovariectomy (RRSO). It is insufficiently clear how to counsel mutation carriers who have been treated for OC, and it may be questioned whether RRM is indicated. It is possible that BC risk, both of primary (PBC) and contralateral BC (CBC), may be modified by the treatment given for OC mostly including surgery and platinum-based chemotherapy. Further, the BC risk has to be weighted against the risk of death after OC. So far, there are no data available on the PBC or CBC risk after OC in BRCA mutation carriers.

Patients and Methods From the database of the institutional Family Cancer Clinic (FCC), we selected BRCA-associated OC patients either without (n= 79, at risk of PBC) or with a history of unilateral BC (n=37, at risk of CBC). Controls were BRCA mutation carriers without OC, either without (n=351) or with a history of unilateral BC (n=294). Follow-up started at OC diagnosis, and for controls at date of first visit at the FCC or the 35th birthday. Exclusion criteria were: other malignancy besides epithelial OC or BC, inadequate follow-up data, bilateral breast cancer or mastectomy. Data analyses were performed using t- and chi-squared tests, and Kaplan-Meier survival method with death prior to BC as competing risk event.

Results Only six OC patients (5.1%) did not receive chemotherapy as part of primary therapy for OC, five at risk of PBC and one at risk of CBC. Chemotherapy schedules were mainly platinum-based (92%). RRSO was performed in 45% of the controls.

The risks of PBC at 2, 5, and 10 years in BRCA-associated OC patients were 3%, 6% and 11%, respectively, versus 6%, 16% and 28% in unaffected BRCA mutation carriers (p=0.03). The mortality rate at those time points in the OC group was 13%, 33% and 61%, respectively, versus 1%, 2% and 2% in unaffected mutation carriers (p&lt;0.001).

In patients with a history of unilateral BC, the risks of CBC at 2, 5, and 10 years in OC patients were 0%, 7% and 7%, respectively, versus 6%, 16% and 34% in the BC patients without OC (p=0.06). The mortality rate at similar time points was 19%, 34%, and 55%, respectively, in the OC group versus 4%, 11%, and 21% for the non-OC patients (p&lt;0.001).

Conclusions The risk of developing a PBC or CBC was much lower in BRCA mutation carriers with a history of OC than in mutation carriers without OC. Also, since the 10-year mortality rate after ovarian cancer was 55–60% and the risk of developing a PBC or CBC at the highest was 11% over the same time period, our data suggest that intensive breast cancer surveillance strategies for the BRCA-associated ovarian cancer group might be reconsidered, while risk reducing mastectomy is not indicated unless in specific cases requiring careful consideration in a multisciplinary setting. Further studies in larger groups are warranted.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-11-04.

Low penetrance breast cancer susceptibility loci are associated with specific breast tumor subtypes: findings from the Breast Cancer Association Consortium

Breast cancers demonstrate substantial biological, clinical and etiological heterogeneity. We investigated breast cancer risk associations of eight susceptibility loci identified in GWAS and two putative susceptibility loci in candidate genes in relation to specific breast tumor subtypes. Subtypes were defined by five markers (ER, PR, HER2, CK5/6, EGFR) and other pathological and clinical features. Analyses included up to 30 040 invasive breast cancer cases and 53 692 controls from 31 studies within the Breast Cancer Association Consortium. We confirmed previous reports of stronger associations with ER+ than ER- tumors for six of the eight loci identified in GWAS: rs2981582 (10q26) (P-heterogeneity = 6.1 × 10(-18)), rs3803662 (16q12) (P = 3.7 × 10(-5)), rs13281615 (8q24) (P = 0.002), rs13387042 (2q35) (P = 0.006), rs4973768 (3p24) (P = 0.003) and rs6504950 (17q23) (P = 0.002). The two candidate loci, CASP8 (rs1045485, rs17468277) and TGFB1 (rs1982073), were most strongly related with the risk of PR negative tumors (P = 5.1 × 10(-6) and P = 4.1 × 10(-4), respectively), as previously suggested. Four of the eight loci identified in GWAS were associated with triple negative tumors (P ≤ 0.016): rs3803662 (16q12), rs889312 (5q11), rs3817198 (11p15) and rs13387042 (2q35); however, only two of them (16q12 and 2q35) were associated with tumors with the core basal phenotype (P ≤ 0.002). These analyses are consistent with different biological origins of breast cancers, and indicate that tumor stratification might help in the identification and characterization of novel risk factors for breast cancer subtypes. This may eventually result in further improvements in prevention, early detection and treatment.

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.

Common genetic variation at BARD1 is not associated with breast cancer risk in BRCA1 or BRCA2 mutation carriers

BACKGROUND

Inherited BRCA1 and BRCA2 (BRCA1/2) mutations confer elevated breast cancer risk. Knowledge of factors that can improve breast cancer risk assessment in BRCA1/2 mutation carriers may improve personalized cancer prevention strategies.

METHODS

A cohort of 5,546 BRCA1 and 2,865 BRCA2 mutation carriers was used to evaluate risk of breast cancer associated with BARD1 Cys557Ser. In a second nonindependent cohort of 1,537 of BRCA1 and 839 BRCA2 mutation carriers, BARD1 haplotypes were also evaluated.

RESULTS

The BARD1 Cys557Ser variant was not significantly associated with risk of breast cancer from single SNP analysis, with a pooled effect estimate of 0.90 (95% CI: 0.71-1.15) in BRCA1 carriers and 0.87 (95% CI: 0.59-1.29) in BRCA2 carriers. Further analysis of haplotypes at BARD1 also revealed no evidence that additional common genetic variation not captured by Cys557Ser was associated with breast cancer risk.

CONCLUSION

Evidence to date does not support a role for BARD1 variation, including the Cy557Ser variant, as a modifier of risk in BRCA1/2 mutation carriers.

IMPACT

Interactors of BRCA1/2 have been implicated as modifiers of BRCA1/2-associated cancer risk. Our finding that BARD1 does not contribute to this risk modification may focus research on other genes that do modify BRCA1/2-associated cancer risk.

Associations of breast cancer risk factors with tumor subtypes: a pooled analysis from the Breast Cancer Association Consortium studies

BACKGROUND

Previous studies have suggested that breast cancer risk factors are associated with estrogen receptor (ER) and progesterone receptor (PR) expression status of the tumors.

METHODS

We pooled tumor marker and epidemiological risk factor data from 35,568 invasive breast cancer case patients from 34 studies participating in the Breast Cancer Association Consortium. Logistic regression models were used in case-case analyses to estimate associations between epidemiological risk factors and tumor subtypes, and case-control analyses to estimate associations between epidemiological risk factors and the risk of developing specific tumor subtypes in 12 population-based studies. All statistical tests were two-sided.

RESULTS

In case-case analyses, of the epidemiological risk factors examined, early age at menarche (≤12 years) was less frequent in case patients with PR(-) than PR(+) tumors (P = .001). Nulliparity (P = 3 × 10(-6)) and increasing age at first birth (P = 2 × 10(-9)) were less frequent in ER(-) than in ER(+) tumors. Obesity (body mass index [BMI] ≥ 30 kg/m(2)) in younger women (≤50 years) was more frequent in ER(-)/PR(-) than in ER(+)/PR(+) tumors (P = 1 × 10(-7)), whereas obesity in older women (>50 years) was less frequent in PR(-) than in PR(+) tumors (P = 6 × 10(-4)). The triple-negative (ER(-)/PR(-)/HER2(-)) or core basal phenotype (CBP; triple-negative and cytokeratins [CK]5/6(+) and/or epidermal growth factor receptor [EGFR](+)) accounted for much of the heterogeneity in parity-related variables and BMI in younger women. Case-control analyses showed that nulliparity, increasing age at first birth, and obesity in younger women showed the expected associations with the risk of ER(+) or PR(+) tumors but not triple-negative (nulliparity vs parity, odds ratio [OR] = 0.94, 95% confidence interval [CI] = 0.75 to 1.19, P = .61; 5-year increase in age at first full-term birth, OR = 0.95, 95% CI = 0.86 to 1.05, P = .34; obesity in younger women, OR = 1.36, 95% CI = 0.95 to 1.94, P = .09) or CBP tumors.

CONCLUSIONS

This study shows that reproductive factors and BMI are most clearly associated with hormone receptor-positive tumors and suggest that triple-negative or CBP tumors may have distinct etiology.

Chemosensitivity and outcome of BRCA1- and BRCA2-associated ovarian cancer patients after first-line chemotherapy compared with sporadic ovarian cancer patients

BACKGROUND

Because it is insufficiently clear whether BRCA-associated epithelial ovarian cancer (EOC) is more chemosensitive than sporadic EOC, we examined response to chemotherapy, progression-free survival (PFS) and overall survival (OS) in BRCA1- and BRCA2-associated versus sporadic EOC patients.

METHODS

Data about patient characteristics, response to and outcome after primary therapy, including chemotherapy, were collected from 99 BRCA1, 13 BRCA2 and 222 sporadic patients. Analyses were carried out using a chi-square test and Kaplan-Meier and Cox regression methods.

RESULTS

Complete response (CR) or no evidence of disease (NED) was observed in 87% of the BRCA1 patients, progressive disease (PD) in 2%, being 71% and 15%, respectively, in sporadic EOC patients (P = 0.002). In BRCA2 patients, 92% had CR/NED, and none PD (P = 0.27). Median PFS in BRCA1, BRCA2 and sporadic patients was 2.1 [95% confidence interval (CI) 1.9-2.5] years (P = 0.006), 5.6 (95% CI 0.0-11.5) years (P = 0.008) and 1.3 (95% CI 1.1-1.5) years, respectively. Median OS in the three groups was 5.9 (95% CI 4.7-7.0) years (P < 0.001), >10 years (P = 0.008), and 2.9 (95% CI 2.2-3.5) years, respectively. A trend for a longer PFS and OS in BRCA2 compared with BRCA1 patients was observed.

CONCLUSION

Compared with sporadic EOC patients, both BRCA1- and BRCA2-associated patients have improved outcomes after primary therapy, including chemotherapy.

BRCA1-Associated Breast Cancers Present Differently From BRCA2-Associated and Familial Cases: Long-Term Follow-Up of the Dutch MRISC Screening Study

Purpose

The Dutch MRI Screening Study on early detection of hereditary breast cancer started in 1999. We evaluated the long-term results including separate analyses of BRCA1 and BRCA2 mutation carriers and first results on survival.

Patients and Methods

Women with higher than 15% cumulative lifetime risk (CLTR) of breast cancer were screened with biannual clinical breast examination and annual mammography and magnetic resonance imaging (MRI). Participants were divided into subgroups: carriers of a gene mutation (50% to 85% CLTR) and two familial groups with high (30% to 50% CLTR) or moderate risk (15% to 30% CLTR).

Results

Our update contains 2,157 eligible women including 599 mutation carriers (median follow-up of 4.9 years from entry) with 97 primary breast cancers detected (median follow-up of 5.0 years from diagnosis). MRI sensitivity was superior to that of mammography for invasive cancer (77.4% v 35.5%; P < .00005), but not for ductal carcinoma in situ. Results in the BRCA1 group were worse compared to the BRCA2, the high-, and the moderate-risk groups, respectively, for mammography sensitivity (25.0% v 61.5%, 45.5%, 46.7%), tumor size at diagnosis ≤ 1 cm (21.4% v 61.5%, 40.9%, 63.6%), proportion of DCIS (6.5% v 18.8%, 14.8%, 31.3%) and interval cancers (32.3% v 6.3%, 3.7%, 6.3%), and age at diagnosis younger than 30 years (9.7% v 0%). Cumulative distant metastasis-free and overall survival at 6 years in all 42 BRCA1/2 mutation carriers with invasive breast cancer were 83.9% (95% CI, 64.1% to 93.3%) and 92.7% (95% CI, 79.0% to 97.6%), respectively, and 100% in the familial groups (n = 43).

Conclusion

Screening results were somewhat worse in BRCA1 mutation carriers, but 6-year survival was high in all risk groups.

Common breast cancer susceptibility alleles and the risk of breast cancer for BRCA1 and BRCA2 mutation carriers: implications for risk prediction

The known breast cancer susceptibility polymorphisms in FGFR2, TNRC9/TOX3, MAP3K1, LSP1, and 2q35 confer increased risks of breast cancer for BRCA1 or BRCA2 mutation carriers. We evaluated the associations of 3 additional single nucleotide polymorphisms (SNPs), rs4973768 in SLC4A7/NEK10, rs6504950 in STXBP4/COX11, and rs10941679 at 5p12, and reanalyzed the previous associations using additional carriers in a sample of 12,525 BRCA1 and 7,409 BRCA2 carriers. Additionally, we investigated potential interactions between SNPs and assessed the implications for risk prediction. The minor alleles of rs4973768 and rs10941679 were associated with increased breast cancer risk for BRCA2 carriers (per-allele HR = 1.10, 95% CI: 1.03-1.18, P = 0.006 and HR = 1.09, 95% CI: 1.01-1.19, P = 0.03, respectively). Neither SNP was associated with breast cancer risk for BRCA1 carriers, and rs6504950 was not associated with breast cancer for either BRCA1 or BRCA2 carriers. Of the 9 polymorphisms investigated, 7 were associated with breast cancer for BRCA2 carriers (FGFR2, TOX3, MAP3K1, LSP1, 2q35, SLC4A7, 5p12, P = 7 × 10(-11) - 0.03), but only TOX3 and 2q35 were associated with the risk for BRCA1 carriers (P = 0.0049, 0.03, respectively). All risk-associated polymorphisms appear to interact multiplicatively on breast cancer risk for mutation carriers. Based on the joint genotype distribution of the 7 risk-associated SNPs in BRCA2 mutation carriers, the 5% of BRCA2 carriers at highest risk (i.e., between 95th and 100th percentiles) were predicted to have a probability between 80% and 96% of developing breast cancer by age 80, compared with 42% to 50% for the 5% of carriers at lowest risk. Our findings indicated that these risk differences might be sufficient to influence the clinical management of mutation carriers.

Sensitivity to Taxane Chemotherapy for Metastatic Breast Cancer in BRCA1 and BRCA2 Mutation Carriers Compared to Sporadic Breast Cancer Patients

Purpose: Data of in vitro and small retrospective studies suggest that breast cancer (BC) (cells) without functional BRCA1 or BRCA2 protein have an increased sensitivity to chemotherapeutic agents causing double strand DNA breaks, while sensitivity to spindle poisons, such as paclitaxel and docetaxel, has been found to be decreased. Clinical data on the latter, however, are very scarce. In this study, we assessed the sensitivity to taxane chemotherapy for metastatic BRCA1/2-associated compared with sporadic breast cancer.Methods: From the family cancer clinic database, we retrieved 36 BRCA1 and 13 BRCA2-associated BC patients treated with taxane chemotherapy for metastatic disease before October 1, 2008, and with available data on follow-up and response assessment. Objective response (OR), and progression-free survival (PFS) after start of taxane chemotherapy were compared with those of 62 sporadic patients with comparable age at diagnosis and year of detection of metastatic BC. A t-test or chi-square test was used to test for differences in characteristics and response types, and Kaplan-Meier survival analysis to calculate PFS.Results: Taxane chemotherapy consisted of docetaxel (n= 76) or paclitaxel (n=21), while 10 (9%) patients received a taxane/trastuzumab regimen. It was given as first-line palliative therapy in 9 BRCA1, 1 BRCA2 and 22 sporadic patients; but mainly as second/third line treatment (BRCA1 n=27, BRCA2 n=12, sporadic patients n=40, respectively). As compared to sporadic patients, BRCA1-associated patients had a significantly lower OR rate (ORR) overall (22% vs 46%, p&lt;0.001) and to 2nd/3rd line taxane treatment (19% vs 46%, p&lt;0.001). Median PFS was shorter in BRCA1 patients (2.0 vs 4.1 mo, p=0.08), with a trend for significance for 2nd/3rd line therapy (1.6 vs 3.9 mo, p=0.05). Also, compared to BRCA2 patients, the ORR in BRCA1 patients was significantly lower, overall as well as to 2nd/3d line therapy (both p=0.003). In BRCA2 mutation carriers compared to sporadic patients, the ORR was higher (75% vs 48%, p=0.28) and PFS longer (6.4 vs 4.1 mo, p=0.33). After exclusion of the patients receiving a taxane/trastuzumab schedule, similar data were observed.Conclusion: Objective response rate to taxane chemotherapy for metastatic disease is lower in BRCA1-associated BC in comparison with sporadic as well as BRCA2-associated BC, resulting in a shorter PFS. If confirmed, these data may have substantial clinical relevance.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 2098.

Sensitivity to First-Line Chemotherapy for Metastatic Breast Cancer in BRCA1 and BRCA2 Mutation Carriers

Purpose

Preclinical as well as a few small retrospective, neoadjuvant studies suggest that breast cancer (cells) without functional BRCA1 or BRCA2 protein have an increased sensitivity to some chemotherapeutic agents causing double-strand DNA breaks. In this study we assessed the sensitivity to standard first-line chemotherapy of metastatic BRCA1/2-associated breast cancer, compared with sporadic breast cancer patients.

Patients and Methods

From the Family Cancer Clinic database, we selected 93 BRCA1- and 28 BRCA2-associated breast cancer patients treated with chemotherapy for metastatic disease before January 1, 2007. Objective response (OR), progression-free survival (PFS), and overall survival (OS) after start of first-line chemotherapy were compared with those of sporadic patients, matched for year of birth, age at diagnosis of primary breast cancer, and year of detection of metastatic disease.

Results

The chemotherapy regimens most frequently used were anthracycline-based (n = 147) and cyclophosphamide, methotrexate, and fluorouracil (CMF)/CMF like (n = 68). As compared to sporadic patients, BRCA2-associated patients had a significantly higher OR (89% v 50%; P = .001), a longer PFS (hazard ratio multivariate [HRmult] 0.64; P = .04) and a prolonged OS (HRmult, 0.53; P = .005) after start of first-line chemotherapy for metastatic breast cancer. For BRCA1-associated patients, a nonsignificant trend for an increased OR (66% v 50%; P = .07), and a longer PFS (HRmult, 0.79; P = .14) after first-line chemotherapy for metastatic breast cancer was observed, but not for OS.

Conclusion

BRCA2-associated breast cancer is more sensitive to standard first-line chemotherapy for metastatic breast cancer in comparison with sporadic breast cancer, especially to anthracyclines. For BRCA1-associated breast cancer no statistically significant higher sensitivity was observed.

Tumour characteristics, survival and prognostic factors of hereditary breast cancer from BRCA2-, BRCA1- and non-BRCA1/2 families as compared to sporadic breast cancer cases

AIM OF THE STUDY

Results on tumour characteristics and survival of hereditary breast cancer (BC), especially on BRCA2-associated BC, are inconclusive. The prognostic impact of the classical tumour and treatment factors in hereditary BC is insufficiently known.

METHODS

We selected 103 BRCA2-, 223 BRCA1- and 311 non-BRCA1/2 BC patients (diagnosis 1980-2004) from the Rotterdam Family Cancer Clinic. To correct for longevity bias, analyses were also performed while excluding index patients undergoing DNA testing 2 years after BC diagnosis. As a comparison group, 759 sporadic BC patients of comparable age at and year of diagnosis were selected. We compared tumour characteristics, the occurrence of ipsilateral recurrence (LRR) and contralateral BC (CBC) as well as distant disease-free (DDFS), BC-specific (BCSS) and overall survival (OS) between these groups. By multivariate modelling, the prognostic impact of tumour and treatment factors was investigated separately in hereditary BC.

RESULTS

We confirmed the presence of the particular BRCA1-phenotype. In contrast, tumour characteristics of BRCA2-associated BC were similar to those of non-BRCA1/2 and sporadic BC, with the exception of a high risk of CBC (3.1% per year) and oestrogen-receptor (ER)-positivity (83%). No significant differences between BRCA2-associated BC and other BC subgroups were found with respect to LRR, DDFS, BCSS and OS. Independent prognostic factors for BC-specific survival in hereditary BC (combining the three subgroups) were tumour stage, adjuvant chemotherapy, histologic grade, ER status and a prophylactic (salpingo-)oophorectomy.

CONCLUSIONS

Apart from the frequent occurrence of contralateral BC and a positive ER-status, BRCA2-associated BC did not markedly differ from other hereditary or sporadic BC. Our observation that tumour size and nodal status are prognostic factors also in hereditary BC implies that the strategy to use these factors as a proxy for ultimate mortality appears to be valid also in this specific group of patients.

Tumor characteristics and detection method in the MRISC screening program for the early detection of hereditary breast cancer

In the MRISC study, women with an inherited risk for breast cancer were screened by a 6-month clinical breast examination (CBE) and yearly MRI and mammography. We found that the MRISC screening scheme could facilitate early breast cancer diagnosis and that MRI was a more sensitive screening method than mammography, but less specific. In the current study we investigated the contribution of MRI in the early detection of breast cancer in relation to tumor characteristics. From November 1999 to October 2003, 1909 women were included and 50 breast cancers were detected, of which 45 were evaluable and included in the current study. We compared the characteristics of tumors detected by MRI-only with those of all other (non-palpable) screen-detected tumors. Further, we compared the sensitivity of mammography and MRI within subgroups according to different tumor characteristics. Twenty-two (49%) of the 45 breast cancers were detected by MRI and not visible at mammography, of which 20 (44%) were also not palpable (MRI-only detected tumors). MRI-only detected tumors were more often node-negative than other screen-detected cancers (94 vs. 59%; P=0.02) and tended to be more often <or=1 cm (58 vs. 31%; P=0.11). MRI was more sensitive than mammography for a wide spectrum of invasive tumor characteristics i.e., size, nodal status, histology, grade and ER status. Half of the breast cancers detected in this study were visible by MRI only and these tumors were smaller and significantly more often node-negative than other screen-detected tumors, suggesting that MRI makes an important contribution to the early detection of hereditary breast cancer.

Differences between first and subsequent rounds of the MRISC breast cancer screening program for women with a familial or genetic predisposition

BACKGROUND

Within the Dutch MRI Screening (MRISC) study, a Dutch multicenter screening study for hereditary breast cancer, the authors investigated whether previously reported increased diagnostic accuracy of magnetic resonance imaging (MRI) compared with mammography would be maintained during subsequent screening rounds.

METHODS

From November 1999 to October 2003, 1909 eligible women were included in the study. Screening parameters and tumor characteristics of different rounds were calculated and compared. The authors defined 3 different types of imaging screening rounds: first round in women never screened by imaging before, first round in women screened by imaging (mainly mammography) before, and subsequent rounds.

RESULTS

The difference in sensitivity for invasive cancers between mammography and MRI was largest in the first round of women previously screened with mammography (20.0 vs. 93.3%; P=.003), but also in subsequent rounds, there was a significant difference in favor of MRI (29.4 vs. 76.5%; P=.02). The difference in false-positive rate between mammography and MRI was also largest in the first round of women previously screened with mammography (5.5 vs. 14.0%; P<.001), and it remained significant in subsequent rounds (4.6 vs. 8.2%; P<.001). Screen-detected tumors were smaller and more often lymph node negative than symptomatic tumors in age-matched control patients, but no major differences in tumor stage were found between tumors detected at subsequent rounds compared with those in the first round.

CONCLUSIONS

In subsequent rounds, a significantly higher sensitivity and better discriminating capacity of MRI compared with mammography was maintained, and a favorable tumor stage compared with age-matched symptomatic controls. As results of these subsequent screening rounds were most predictive for long-term effects, the authors expect that this screening program will contribute to a decrease of breast cancer mortality in these high-risk women.

Factors Affecting Sensitivity and Specificity of Screening Mammography and MRI in Women with an Inherited Risk for Breast Cancer

BACKGROUND

The MRISC study is a screening study, in which women with an increased risk of hereditary breast cancer are screened by a yearly mammography and MRI, and half-yearly clinical breast examination. The sensitivity found in this study was 40% for mammography and 71% for MRI and the specificity was 95 and 90%, respectively. In the current subsequent study we investigated whether these results are influenced by age, a BRCA1/2 mutation, menopausal status and breast density.

PATIENTS AND METHODS

From November 1999 to October 2003, 1909 eligible women were screened and 50 breast cancers were detected. For the current analysis, data of 4134 screening rounds and 45 detected breast cancers were used. For both imaging modalities, screening parameters, receiver operating characteristic (ROC) curves and uni- and multivariate odds ratios (ORs) were calculated. All analyses were separately performed for age at entry (< 40, 40-49, > or =50), mutation status, menopausal status and breast density.

RESULTS

Sensitivity of MRI was decreased in women with high breast density (adjusted OR 0.08). False-positive rates of both mammography (OR(adj) 1.67) and MRI (OR(adj) 1.21) were increased by high breast density, that of MRI by pre-menopausal status (OR(adj) 1.70), young age (OR(adj) 1.58 for women 40-49 years versus women > or =50 years) and decreased in BRCA1/2 mutation carriers (OR(adj) 0.74). In all investigated subgroups the discriminating capacity (measured by the area under the ROC-curve) was higher for MRI than for mammography, with the largest differences for BRCA1/2 mutation carriers (0.237), for women between 40 and 49 years (0.227) and for women with a low breast density (0.237).

CONCLUSIONS

This report supports the earlier recommendation that MRI should be a standard screening method for breast cancer in BRCA1/2 mutation carriers.