Limited family structure and triple-negative breast cancer (TNBC) subtype as predictors of BRCA mutations in a genetic counseling cohort of early-onset sporadic breast cancers

Ultrasonic Features and Molecular Subtype Predict Somatic Mutations in TP53 and PIK3CA Genes in Breast Cancer

RATIONALE AND OBJECTIVES

To predict mutations in TP53 and PIK3CA genes in breast cancer using ultrasound (US) signatures and clinicopathology.

MATERIALS AND METHODS

In this study, we developed and trained a model in 386 breast cancer patients to predict TP53 and PIK3CA mutations. The clinicopathological and US characteristics (including two-dimensional and color Doppler US) were investigated. Statistically significant variables were used to build predictive models, then a combined model was developed using the multivariate logistic regression analysis.

RESULTS

Univariate and multivariate analyses revealed that calcifications on US was an independent predictor of TP53 mutation (p < 0.05), whereas diameter on US and US type were independent predictors of PIK3CA mutation in breast cancer (all p < 0.05). Meanwhile, Luminal B/Human epidermal growth factor receptor two-positive (HER2+), HER2+/estrogen receptor-negative (ER-), and triple-negative breast cancer (TNBC) subtypes were strong predictors of TP53 mutation (odds ratio [OR] = 3.13, 3.18, 3.44, respectively, all p < 0.05). HER2+/ER- and TNBC subtypes were negative predictors of PIK3CA mutation (OR = 0.223, 0.241, respectively, all p < 0.05). The areas under curves (AUCs) for PIK3CA mutation in the training set increased from 0.553-0.610 to 0.741 in the multivariate model that combined US features and molecular subtype, with a sensitivity and specificity of 80.6% and 58.7%, respectively. The application of the multivariate model in the validation set achieved acceptable discrimination (AUC = 0.715). For TP53 mutation, the AUC was 0.653.

CONCLUSION

US is a non-invasive modality to recognize the presence of TP53 and PIK3CA mutation. The models combined with US features and molecular subtype have implications for the practical application of predicting gene mutation for individual decision-making regarding treatment planning.

Molecular Classification and Future Therapeutic Challenges of Triple-negative Breast Cancer

Triple-negative breast cancer (TNBC) is an extremely diverse group of breast tumors, with aggressive clinical behavior, higher rates of distant recurrence and worse overall survival compared to other types of breast cancers. The genetic, transcriptional histological and clinical heterogeneity of this disease has been an obstacle in the progression of targeted therapeutic approaches, as a ubiquitous TNBC marker has not yet been discerned. In terms of that, current studies focus on the classification of TNBC tumors in subgroups with similar characteristics in order to develop a treatment specialized for each group of patients. To date, a series of gene expression profiles analysis in order to identify the different molecular subtypes have been used. Complementary DNA microarrays, PAM50 assays, DNA and RNA sequencing as well as immunohistochemical analysis are some of the methods utilized to classify TNBC tumors. In 2012, the Cancer Genome Atlas (TCGA) Research Network conducted a major analysis of breast cancers using six different platforms, the genomic DNA copy number arrays, DNA methylation, exome sequencing, messenger RNA arrays, microRNA sequencing and reverse-phase protein arrays, in order to assort the tumors in homogenous subgroups. Since then, an increasing number of breast cancer data sets are being examined in an attempt to distinguish the classification with biological interpretation and clinical implementation. In this review, the progress in molecular subtyping of TNBC is discussed, providing a brief insight in novel TNBC biomarkers and therapeutic strategies.

Breast MRI texture analysis for prediction of BRCA-associated genetic risk

Background

BRCA1/2 deleterious variants account for most of the hereditary breast and ovarian cancer cases. Prediction models and guidelines for the assessment of genetic risk rely heavily on criteria with high variability such as family cancer history. Here we investigated the efficacy of MRI (magnetic resonance imaging) texture features as a predictor for BRCA mutation status.

Methods

A total of 41 female breast cancer individuals at high genetic risk, sixteen with a BRCA1/2 pathogenic variant and twenty five controls were included. From each MRI 4225 computer-extracted voxels were analyzed. Non-imaging features including clinical, family cancer history variables and triple negative receptor status (TNBC) were complementarily used. Lasso-principal component regression (L-PCR) analysis was implemented to compare the predictive performance, assessed as area under the curve (AUC), when imaging features were used, and lasso logistic regression or conventional logistic regression for the remaining analyses.

Results

Lasso-selected imaging principal components showed the highest predictive value (AUC 0.86), surpassing family cancer history. Clinical variables comprising age at disease onset and bilateral breast cancer yielded a relatively poor AUC (~ 0.56). Combination of imaging with the non-imaging variables led to an improvement of predictive performance in all analyses, with TNBC along with the imaging components yielding the highest AUC (0.94). Replacing family history variables with imaging components yielded an improvement of classification performance of ~ 4%, suggesting that imaging compensates the predictive information arising from family cancer structure.

Conclusions

The L-PCR model uncovered evidence for the utility of MRI texture features in distinguishing between BRCA1/2 positive and negative high-risk breast cancer individuals, which may suggest value to diagnostic routine. Integration of computer-extracted texture analysis from MRI modalities in prediction models and inclusion criteria might play a role in reducing false positives or missed cases especially when established risk variables such as family history are missing.

Comparison of clinical features and oncologic outcomes between familial non-hereditary and hereditary breast cancer in Korean female patients

BACKGROUND

The authors compared the clinical features between familial (non-hereditary) and hereditary breast cancer. And we also analyzed their oncologic outcomes to establish appropriate surveillance protocol for familial (non-hereditary) and hereditary breast cancer.

METHODS

Among 232 patients with breast cancer who were performed BRCA gene evaluation, twenty-eight patients were diagnosed as hereditary breast cancer with BRCA gene mutation and one-hundred and seventy-six patients were familial (non-hereditary) breast cancer. The clinical characteristics and oncologic outcomes were compared between two groups.

RESULTS

While the incidence of multifocality was higher in familial (non-hereditary) breast cancer group (p < 0.001), the bilaterality was higher in hereditary breast cancer group (p < 0.001). And the rate of pathologic complete remission was also significantly higher in hereditary breast cancer group (p = 0.030). The characteristics of tumor were different between familial (non-hereditary) breast cancer and hereditary breast cancer. The oncologic outcome was better in familial (non-hereditary) breast cancer group than hereditary breast cancer group except death.

CONCLUSION

The clinical characteristics of familial (non-hereditary) breast cancer were different from those of hereditary breast cancer but similar to those of sporadic breast cancer. The prognosis of the familial (non-hereditary) breast cancer was significantly better than hereditary breast cancer.

A systematic review of the international prevalence of BRCA mutation in breast cancer

A systematic review was conducted, summarizing international BRCA 1 or 2 (BRCA1/2) mutation prevalence in breast cancer. Databases (eg, Medline and Embase; N=7) and conferences were searched (January 2012 to December 2017). From 17,872 records, 70 studies were included. In 58 large (N>100) studies, BRCA1/2 mutation prevalence varied widely from 1.8% (Spain) in sporadic breast cancer to 36.9% (United States) in estrogen receptor/progesterone receptor low+ (1-9% on immunohistochemistry/human epidermal growth factor receptor 2-negative [HER2-]) breast cancer. In 2 large studies unselected for family history, ethnicity, sex, or age and no/unclear selection by breast cancer stage or hormone receptor (HR) status, germline BRCA (gBRCA) mutation prevalence was 2.9% (Italy) to 3.0% (South Korea). In the 4 large unselected triple-negative breast cancer studies, gBRCA mutation prevalence varied from 9.3% (Australia) to 15.4% (United States). gBRCA mutation prevalence in 1 large unselected HR positive/HER2- early breast cancer study was 5% (United States). In 2 large unselected metastatic breast cancer studies, gBRCA mutation prevalence was 2.7% (France) and 4.3% (Germany). Locally advanced breast cancer studies were small and not in unselected populations. Poor reporting of gBRCA status and basis of selection implies a need for further large well-reported BRCA mutation prevalence studies in breast cancer.

BRCA1/2 mutation spectrum in Chinese early-onset breast cancer

Background

Breast cancer is the most commonly diagnosed cancer among women. Although many studies have reported the BRCA mutations among breast cancer patients, few studies have focused among Chinese early-onset breast cancer patients. The purpose of this study is to identify BRCA1 and BRCA2 mutation features and their clinical significance of early-onset Chinese breast cancer patients.

Methods

A total of 54 female patients diagnosed with breast cancer were enrolled in this study, of which 27 were younger than 40 (study group, mean age 32 years, range, 23–40 years) and 27 were older than 40 (control group, mean age 52 years, range, 41–68 years). Tumor FFPE samples were collected for somatic mutation test, while blood samples or normal tissue were used for germline mutation by both PGM and Miseq platform. All codon exons and functional introns for BRCA1/2 were covered. The clinical significance of mutation types was cross analyzed in several available database. The novel mutations were confirmed by sanger sequencing.

Results

In study group, 14.8% (4/27) and 3.7% (1/27) patients had deleterious BRCA1/2 germline and somatic mutations respectively. While in control group, only 3.7% (1/27) and 7.4% (2/27) had deleterious BRCA1/2 germline and somatic mutations respectively. BRCA1 germline mutation c.2623C>T and BRCA2 germline mutation c.5852G>A were found to be novel mutation sites and confirmed by sanger sequencing.

Conclusions

Our study found two novel BRCA1/2 mutation sites in early-onset breast cancer, and also showed that early-onset breast cancer patients are more likely to harbor germline mutations with deleterious and uncertain significance.

Association Between BRCA Status and Triple-Negative Breast Cancer: A Meta-Analysis

Triple-negative breast cancer (TNBC) is a subtype of aggressive breast cancer and characterized by a lack of the expression of estrogen receptor, progesterone receptor and human epidermal growth factor receptor 2. BRCA genes are tumor-suppressor genes that are involved in DNA damage repair and mutations of BRCA genes may increase the risk of developing breast cancer and/or ovarian cancer due to defective DNA repair mechanisms. However, the relationship between BRCA status and TNBC needs to be further investigated and validated. The aim of this meta-analysis was to evaluate the association between BRCA status and TNBC. We systematically searched the electronic databases of MEDLINE (PubMed), Embase, and Cochrane Library to identify relevant publications from April, 1959 to November, 2017. The data from the studies were examined by a meta-analysis using STATA software to calculate the odds ratio (OR) with 95% confidence interval (CI) by fixed-effect and random-effect models. We identified 16 qualified studies from 527 publications with 46,870 breast cancer patients including 868 BRCA1 mutations (BRCA1^Mut) carriers, 739 BRCA2 mutations (BRCA2^Mut) carriers, and 45,263 non-carriers. The results showed that breast cancer patients with BRCA1^Mut carriers were more likely to have TNBC than those of BRCA2^Mut carriers (OR: 3.292; 95% CI: 2.773–3.909) or non-carriers (OR: 8.889; 95% CI: 6.925–11.410). Furthermore, high expression of nuclear grade and large tumor burden (>2 cm) were significantly more common in breast cancer patients with BRCA1^Mut carriers than those of BRCA2^Mut carriers (OR: 2.663; 95% CI: 1.731–4.097; P = 0.211) or non-carriers (OR: 1.577; 95% CI: 1.067–2.331; P = 0.157). The data suggest that breast cancer patients with BRCA1^Mut are more likely to have TNBC, high nuclear grade, and larger tumor burden.

Frequency of breast cancer with hereditary risk features in Spain: Analysis from GEICAM "El Álamo III" retrospective study

PURPOSE

To determine the frequency of breast cancer (BC) patients with hereditary risk features in a wide retrospective cohort of patients in Spain.

METHODS

a retrospective analysis was conducted from 10,638 BC patients diagnosed between 1998 and 2001 in the GEICAM registry "El Álamo III", dividing them into four groups according to modified ESMO and SEOM hereditary cancer risk criteria: Sporadic breast cancer group (R0); Individual risk group (IR); Familial risk group (FR); Individual and familial risk group (IFR) with both individual and familial risk criteria.

RESULTS

7,641 patients were evaluable. Of them, 2,252 patients (29.5%) had at least one hereditary risk criteria, being subclassified in: FR 1.105 (14.5%), IR 970 (12.7%), IFR 177 (2.3%). There was a higher frequency of newly diagnosed metastatic patients in the IR group (5.1% vs 3.2%, p = 0.02). In contrast, in RO were lower proportion of big tumors (> T2) (43.8% vs 47.4%, p = 0.023), nodal involvement (43.4% vs 48.1%, p = 0.004) and lower histological grades (20.9% G3 for the R0 vs 29.8%) when compared to patients with any risk criteria.

CONCLUSIONS

Almost three out of ten BC patients have at least one hereditary risk cancer feature that would warrant further genetic counseling. Patients with hereditary cancer risk seems to be diagnosed with worse prognosis factors.

Alarming Burden of Triple-Negative Breast Cancer in India

Breast cancer is the most prevalent cancer among women worldwide. Among the different breast cancer subtypes, triple-negative breast cancer (TNBC), which is more prevalent among younger age women, is the most aggressive form. Numerous clinicopathologic studies performed throughout the world strongly support the utterly poor prognoses and high recurrence rate of TNBC. The present report details a thorough data survey from Google and PubMed on the burden of TNBC worldwide and other associated factors, with special emphasis on its ever increasing incidence among Indian women. Our analysis revealed that the proportion of TNBC ranges from 6.7% to 27.9% in different countries, with the highest reported percentage in India among all, followed by Indonesia, Algeria, and Pakistan. Most of the other countries (Netherlands, Italy, London, Germany) had a TNBC incidence less than the mean level (ie, 15%). The high incidence of TNBC in the Indian population is associated with vivid risk factors, which primarily include lifestyle, deprivation status, obesity, family history, high mitotic indexes, and BRCA1 mutations. The treatment of TNBC is greatly hampered due to the lack of targeted therapies. Hence, it requires earnest attention towards extensive research for the prevention and development of treatment modalities with high efficacy.

Lymph node status as a prognostic factor in BRCA-positive breast cancer

BACKGROUND

The incidence of ipsilateral breast tumor recurrence (IBTR) seems to be higher in BRCA-positive than sporadic breast cancer. We compared the oncologic outcomes of BRCA-positive breast cancer patients managed with breast-conserving surgery, simple mastectomy or mastectomy followed by immediate reconstruction.

MATERIALS/METHODS

Thirty four BRCA-positive breast cancers were grouped according to surgical treatment: breast-conserving surgery (n = 17), simple mastectomy (n = 9), and mastectomy followed by immediate reconstruction (n = 8). Clinicopathologic factors and oncologic outcomes were compared during a 3-y mean follow-up.

RESULTS

Neoadjuvant radiotherapy and nodal and pathologic stages differed significantly between the breast-conserving and simple mastectomy groups. There was no oncologic event in the breast-conserving group during follow-up; however, IBTR and distant metastasis occurred in the simple mastectomy and mastectomy followed by immediate reconstruction groups. Nodal stage was associated with IBTR in both these groups whereas pathologic stage was associated with distant metastasis only in the simple mastectomy group.

CONCLUSIONS

Although there were no differences in oncologic outcomes between the three groups, the nodal stage was strongly associated with IBTR in patients with BRCA-positive breast cancer. IBTR may be attributable to nodal stage and pathologic tumor stage.

Efficacy of Neoadjuvant Carboplatin plus Docetaxel in Triple-Negative Breast Cancer: Combined Analysis of Two Cohorts

PURPOSE

Recent studies demonstrate that addition of neoadjuvant (NA) carboplatin to anthracycline/taxane chemotherapy improves pathologic complete response (pCR) in triple-negative breast cancer (TNBC). Effectiveness of anthracycline-free platinum combinations in TNBC is not well known. Here, we report efficacy of NA carboplatin + docetaxel (CbD) in TNBC.

EXPERIMENTAL DESIGN

The study population includes 190 patients with stage I-III TNBC treated uniformly on two independent prospective cohorts. All patients were prescribed NA chemotherapy regimen of carboplatin (AUC 6) + docetaxel (75 mg/m2) given every 21 days × 6 cycles. pCR (no evidence of invasive tumor in the breast and axilla) and residual cancer burden (RCB) were evaluated.

RESULTS

Among 190 patients, median tumor size was 35 mm, 52% were lymph node positive, and 16% had germline BRCA1/2 mutation. The overall pCR and RCB 0 + 1 rates were 55% and 68%, respectively. pCRs in patients with BRCA-associated and wild-type TNBC were 59% and 56%, respectively (P = 0.83). On multivariable analysis, stage III disease was the only factor associated with a lower likelihood of achieving a pCR. Twenty-one percent and 7% of patients, respectively, experienced at least one grade 3 or 4 adverse event.

CONCLUSIONS

The CbD regimen was well tolerated and yielded high pCR rates in both BRCA-associated and wild-type TNBC. These results are comparable with pCR achieved with the addition of carboplatin to anthracycline-taxane chemotherapy. Our study adds to the existing data on the efficacy of platinum agents in TNBC and supports further exploration of the CbD regimen in randomized studies. Clin Cancer Res; 23(3); 649-57. ©2016 AACR.

Current advances in biomarkers for targeted therapy in triple-negative breast cancer

Triple-negative breast cancer (TNBC) is a complex heterogeneous disease characterized by the absence of three hallmark receptors: human epidermal growth factor receptor 2, estrogen receptor, and progesterone receptor. Compared to other breast cancer subtypes, TNBC is more aggressive, has a higher prevalence in African-Americans, and more frequently affects younger patients. Currently, TNBC lacks clinically accepted targets for tailored therapy, warranting the need for candidate biomarkers. BiomarkerBase, an online platform used to find biomarkers reported in clinical trials, was utilized to screen all potential biomarkers for TNBC and select only the ones registered in completed TNBC trials through clinicaltrials.gov. The selected candidate biomarkers were classified as surrogate, prognostic, predictive, or pharmacodynamic (PD) and organized by location in the blood, on the cell surface, in the cytoplasm, or in the nucleus. Blood biomarkers include vascular endothelial growth factor/vascular endothelial growth factor receptor and interleukin-8 (IL-8); cell surface biomarkers include EGFR, insulin-like growth factor binding protein, c-Kit, c-Met, and PD-L1; cytoplasm biomarkers include PIK3CA, pAKT/S6/p4E-BP1, PTEN, ALDH1, and the PIK3CA/AKT/mTOR-related metabolites; and nucleus biomarkers include BRCA1, the gluco-corticoid receptor, TP53, and Ki67. Candidate biomarkers were further organized into a "cellular protein network" that demonstrates potential connectivity. This review provides an inventory and reference point for promising biomarkers for breakthrough targeted therapies in TNBC.

Mutation detection rates associated with specific selection criteria for BRCA1/2 testing in 1854 high-risk families: A monocentric Italian study

BACKGROUND

BRCA mutation screening is frequently offered on the basis of the fulfillment of empirical selection criteria, thought to be indicative of a genetic predisposition to breast/ovarian cancer (BrCa/OvCa). This study aimed to evaluate, in a large cohort of BrCa/OvCa families, the mutation detection rate (DR) associated with specific clinical features and the relative performance of the employed selection criteria.

METHODS

BRCA gene analysis was performed on 1854 family probands. The Fisher exact test was used to compare the DRs associated with different clinical features. In a subset of families fulfilling only mutually exclusive criteria, odds ratios and 95% CI were estimated to test the relative effectiveness of each criterion.

RESULTS

The overall DR was 29.3%. Among BrCa-only families, the DRs were significantly higher in the presence of early-onset compared with late-onset cases, and of bilateral compared with unilateral cases. In families with bilateral cases, ages at diagnosis of both the first and second tumour were significantly lower in mutation carriers. In families fulfilling mutually exclusive criteria, OvCa was the best predictor of BRCA mutations, with DRs (range: 31.8%-80.0%) significantly higher compared with the other criteria. Conversely, isolated early-onset BrCa and three or more late-onset BrCa displayed significantly lower predictive values (7.9% and 7.2%, respectively).

CONCLUSIONS

The observed estimates, albeit confirming a DR above 10% for most of the considered criteria, highlighted some relevant differences among them. Such differences should be taken into account in the identification of patients who might benefit from genetic counselling and subsequent testing.