TP53 Mutational Analysis Enhances the Prognostic Accuracy of IHC4 and PAM50 Assays

IHC4 and PAM50 assays have been shown to provide additional prognostic information for patients with early breast cancer. We evaluated whether incorporating TP53 mutation analysis can further enhance their prognostic accuracy. We examined TP53 mutation and the IHC4 score in tumors of 605 patients diagnosed with stage I-III breast cancer at National Taiwan University Hospital (the NTUH cohort). We obtained information regarding TP53 mutation and PAM50 subtypes in 699 tumors from the Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) cohort. We found that TP53 mutation was significantly associated with high-risk IHC4 group and with luminal B, HER2-enriched, and basal-like subtypes. Despite the strong associations, TP53 mutation independently predicted shorter relapse-free survival (hazard ratio [HR] = 1.63, P = 0.007) in the NTUH cohort and shorter breast cancer-specific survival (HR = 2.35, P = <0.001) in the METABRIC cohort. TP53 mutational analysis added significant prognostic information in addition to the IHC4 score (∆ LR-χ(2) = 8.61, P = 0.002) in the NTUH cohort and the PAM50 subtypes (∆ LR-χ(2) = 18.9, P = <0.001) in the METABRIC cohort. We conclude that incorporating TP53 mutation analysis can enhance the prognostic accuracy of the IHC4 and PAM50 assays.

Adjuvant Lapatinib and Trastuzumab for Early Human Epidermal Growth Factor Receptor 2-Positive Breast Cancer: Results From the Randomized Phase III Adjuvant Lapatinib and/or Trastuzumab Treatment Optimization Trial

BACKGROUND

Lapatinib (L) plus trastuzumab (T) improves outcomes for metastatic human epidermal growth factor 2-positive breast cancer and increases the pathologic complete response in the neoadjuvant setting, but their role as adjuvant therapy remains uncertain.

METHODS

In the Adjuvant Lapatinib and/or Trastuzumab Treatment Optimization trial, patients with centrally confirmed human epidermal growth factor 2-positive early breast cancer were randomly assigned to 1 year of adjuvant therapy with T, L, their sequence (T→L), or their combination (L+T). The primary end point was disease-free survival (DFS), with 850 events required for 80% power to detect a hazard ratio (HR) of 0.8 for L+T versus T.

RESULTS

Between June 2007 and July 2011, 8,381 patients were enrolled. In 2011, due to futility to demonstrate noninferiority of L versus T, the L arm was closed, and patients free of disease were offered adjuvant T. A protocol modification required P ≤ .025 for the two remaining pairwise comparisons. At a protocol-specified analysis with a median follow-up of 4.5 years, a 16% reduction in the DFS hazard rate was observed with L+T compared with T (555 DFS events; HR, 0.84; 97.5% CI, 0.70 to 1.02; P = .048), and a 4% reduction was observed with T→L compared with T (HR, 0.96; 97.5% CI, 0.80 to 1.15; P = .61). L-treated patients experienced more diarrhea, cutaneous rash, and hepatic toxicity compared with T-treated patients. The incidence of cardiac toxicity was low in all treatment arms.

CONCLUSION

Adjuvant treatment that includes L did not significantly improve DFS compared with T alone and added toxicity. One year of adjuvant T remains standard of care.

Current Status of the Management of Hereditary Breast and Ovarian Cancer in Asia: First Report by the Asian BRCA Consortium

BACKGROUND

BRCA1/BRCA2 mutations are associated with an increased lifetime risk for hereditary breast and ovarian cancer (HBOC). Compared with the Western developed countries, genetic testing and risk assessment for HBOC in Asia are less available, thus prohibiting the appropriate surveillance, clinical strategies and cancer management.

METHODS

The current status of HBOC management in 14 Asian countries, including genetic counselling/testing uptakes and clinical management options, was reviewed. We analysed how economic factors, healthcare and legal frameworks, and cultural issues affect the genetic service availability in Asia.

RESULTS

In 2012, only an estimated 4,000 breast cancer cases from 14 Asian countries have benefited from genetic services. Genetic testing costs and the absence of their adoption into national healthcare systems are the main economic barriers for approaching genetic services. Training programmes, regional accredited laboratories and healthcare professionals are not readily available in most of the studied countries. A lack of legal frameworks against genetic discrimination and a lack of public awareness of cancer risk assessment also provide challenges to HBOC management in Asia.

CONCLUSIONS

The Asian BRCA Consortium reports the current disparities in genetic services for HBOC in Asia and urges the policy makers, healthcare sectors and researchers to address the limitations in HBOC management.

An efficient and robust fatty acid profiling method for plasma metabolomic studies by gas chromatography-mass spectrometry

BACKGROUND

Targeted metabolomic analysis of fatty acids has linked the dysregulation of fatty acids to many diseases. This study selected five frequently used fatty acid derivatization methods for comparison.

METHODS

We compared the method precisions and derivatization efficiencies, the most economical and best performing method was subjected to method validation. Twenty-four fatty acid standards were used to validate the method, which was later applied to the investigation of potential fatty acid markers of breast cancer.

RESULTS

The acetyl chloride method was demonstrated to provide the best derivatization efficiency and lowest cost for plasma samples. The ionic liquid column successfully separated positional and geometric fatty acid isomers within 26 min under the optimized conditions. Intra-day and inter-day CVs for most of the fatty acids were <10%. Over 90% of the results showed recoveries within 85%-115%. The validated method was applied to investigate potential fatty acid markers of breast cancer. The fatty acid profiling results revealed that 3 fatty acids (C22:0, C24:0, C18:2n6) were significantly lower in both pre- and post-menopausal breast cancer patients (P<0.05).

CONCLUSIONS

We demonstrated that the proposed method is an accurate, efficient and economical method for plasma metabolomic studies of fatty acids.

Mutational analysis of MED12 exon 2 in a spectrum of fibroepithelial tumours of the breast: implications for pathogenesis and histogenesis

AIMS

Fibroadenomas (FAs) and phyllodes tumours (PTs) are fibroepithelial tumours. Mutations in MED12 exon 2 have been reported in FAs. This study investigated the MED12 mutations in a spectrum of fibroepithelial tumours.

METHODS AND RESULTS

Using direct sequencing, we analysed MED12 exon 2 mutations on 121 samples, including PTs and FAs and variants. We found MED12 mutations in 71.4% of PTs. No significant difference in the mutation frequency was observed between benign, borderline and malignant PTs, and a general lack of correlation existed between mutations and pathological factors associated with PT grading. The mutation patterns were similar between PTs and FAs, with codon 44 being involved most frequently. MED12 mutations were identified in 47.1, 52.6 and 50.0% of complex FAs, juvenile FAs and tubular adenomas (TAs), respectively, and the frequency and mutation patterns were similar between these FA variants and usual FAs.

CONCLUSIONS

The high frequency and similar patterns of MED12 mutations in FAs and various grades of PTs implies that the MED12 mutation is a common and early pathological event in these fibroepithelial tumours. The similar frequency and patterns of the MED12 mutation between FAs and variants suggests that FA variants are bona fide FAs, with identical pathogenesis involving MED12 mutations.

Intensity-Invariant Texture Analysis for Classification of BI-RADS Category 3 Breast Masses

Radiologists likely incorrectly classify benign masses as Breast Imaging Reporting and Data System (BI-RADS) category 3. A computer-aided diagnosis (CAD) system was developed in this study as a second viewer to avoid misclassification of carcinomas. Sixty-nine biopsy-proven BI-RADS category 3 masses, including 21 malignant and 48 benign masses, were used to evaluate the CAD system. To improve the texture features, gray-scale variations between images were reduced by transforming pixels into intensity-invariant ranklet coefficients. The textures of the tumor and speckle pixels were extracted from the transformed ranklet images to provide more robust features than in conventional CAD systems. As a result, tumor texture and speckle texture with ranklet transformation achieved significantly better areas under the receiver operating characteristic curve (Az) compared with those without ranklet transformation (Az = 0.83 vs. 0.58 and Az = 0.80 vs. 0.56, p value < 0.05). The improved CAD system can be a second reader to confirm the classification of BI-RADS category 3 masses.

Personalization of loco-regional care for primary breast cancer patients (part 1)

ABSTRACT 

Kyoto Breast Cancer Consensus Conference, Kyoto, Japan, 18–20 February 2014

The loco-regional management of breast cancer is increasingly complex with application of primary systemic therapies, oncoplastic techniques and genetic testing for breast cancer susceptibility. Personalization of loco-regional treatment is integral to optimization of breast cancer care. Clinical and pathological tumor stage, biological features and host factors influence loco-regional treatment strategies and extent of surgical procedures. Key issues including axillary staging, axillary treatment, radiation therapy, primary systemic therapy (PST), preoperative hormonal therapy and genetic predisposition were identified and discussed at the Kyoto Breast Cancer Consensus Conference (KBCCC2014). In the first of a two part conference scene, consensus recommendations for axillary management are presented and focus on the following topics: indications for completion axillary lymph node dissection in primary surgical patients with ≤2 macrometastases or any sentinel nodal deposits after PST; the timing of sentinel lymph node biopsy in the context of PST; use of axillary irradiation as a component of primary treatment plans and the role of intraoperative node assessment in the post-Z0011 era.

Personalization of loco-regional care for primary breast cancer patients (part 2)

ABSTRACT 

Kyoto Breast Cancer Consensus Conference, Kyoto, Japan, 18–20 February 2014

The loco-regional management of breast cancer is increasingly complex with application of primary systemic therapies, oncoplastic techniques and genetic testing for breast cancer susceptibility. Personalization of loco-regional treatment is integral to optimization of breast cancer care. Clinical and pathological tumor stage, biological features and host factors influence loco-regional treatment strategies and extent of surgical procedures. Key issues including axillary staging, axillary treatment, radiation therapy, primary systemic therapy (PST), preoperative hormonal therapy and genetic predisposition were identified and discussed at the Kyoto Breast Cancer Consensus Conference (KBCCC2014). In the second of a two part conference scene, consensus recommendations for radiation treatment, primary systemic therapies and management of genetic predisposition are reported and focus on the following topics: influence of both clinical response to PST and stage at presentation on recommendations for postmastectomy radiotherapy; use of regional nodal irradiation in selected node-positive patients and those with adverse pathological factors; extent of surgical resection following downstaging of tumors with PST; use of preoperative hormonal therapy in premenopausal women with larger, node-negative luminal A-like tumors and managing increasing demands for contralateral prophylactic mastectomy in patients with a unilateral sporadic breast cancer.

High Prevalence of the BIM Deletion Polymorphism in Young Female Breast Cancer in an East Asian Country

Background

A rapid surge of female breast cancer has been observed in young women in several East Asian countries. The BIM deletion polymorphism, which confers cell resistance to apoptosis, was recently found exclusively in East Asian people with prevalence rate of 12%. We aimed to evaluate the possible role of this genetic alteration in carcinogenesis of breast cancer in East Asians.

Method

Female healthy volunteers (n = 307), patients in one consecutive stage I-III breast cancer cohort (n = 692) and one metastatic breast cancer cohort (n = 189) were evaluated. BIM wild-type and deletion alleles were separately genotyped in genomic DNAs.

Results

Both cancer cohorts consistently showed inverse associations between the BIM deletion polymorphism and patient age (≤35 y vs. 36-50 y vs. >50 y: 29% vs. 22% vs. 15%, P = 0.006 in the consecutive cohort, and 40% vs. 23% vs. 13%, P = 0.023 in the metastatic cohort). In healthy volunteers, the frequencies of the BIM deletion polymorphism were similar (13%-14%) in all age groups. Further analyses indicated that the BIM deletion polymorphism was not associated with specific clinicopathologic features, but it was associated with poor overall survival (adjusted hazard ratio 1.71) in the consecutive cohort.

Conclusions

BIM deletion polymorphism may be involved in the tumorigenesis of the early-onset breast cancer among East Asians.

Evaluation of the treatment response to neoadjuvant chemotherapy in locally advanced breast cancer using combined magnetic resonance vascular maps and apparent diffusion coefficient

PURPOSE

To evaluate the treatment response of locally advanced breast cancer (LABC) to neoadjuvant chemotherapy using magnetic resonance (MR) vascular maps and apparent diffusion coefficient (ADC) at 3T. Materials and Methods Thirty-one patients with LABC who underwent breast MR studies before, after the first course, and after completing neoadjuvant chemotherapy were enrolled. Vascular morphology was retrieved via Hessian matrix and the voxels of the vessels and volume of vessels were measured automatically. Whole tumor mean ADC values were calculated. Clinical responders were defined as >50% tumor reduction in the final MR studies. Pathologically complete responders were also recorded.

RESULTS

There were 21 clinical responders and 10 nonresponders. Compared to the nonresponders after the first course, the responders were characterized by more vascular reduction of the breast lesion and decreased bilateral vascular discrepancy (voxels and volume), and increments in the ADC value and ADC percentage of the lesions (all P < 0.05). There were three pathological complete responders who showed more apparent early vascular reduction of the lesion breast (voxels and volume) and increments in the ADC value than others (P = 0.02, 0.01 and 0.02, respectively).

CONCLUSION

The early changes of MR vascular maps and ADC are associated with the final treatment response of LABC.

A novel 96well-formatted micro-gap plate enabling drug response profiling on primary tumour samples

Drug-based treatments are the most widely used interventions for cancer management. Personalized drug response profiling remains inherently challenging with low cell count harvested from tumour sample. We present a 96well-formatted microfluidic plate with built-in micro-gap that preserves up to 99.2% of cells during multiple assay/wash operation and only 9,000 cells needed for a single reagent test (i.e. 1,000 cells per test spot x 3 selected concentration x triplication), enabling drug screening and compatibility with conventional automated workstations. Results with MCF7 and MDA-MB-231 cell lines showed that no statistical significance was found in dose-response between the device and conventional 96-well plate control. Primary tumour samples from breast cancer patients tested in the device also showed good IC₅₀ prediction. With drug screening of primary cancer cells must consider a wide range of scenarios, e.g. suspended/attached cell types and rare/abundant cell availability, the device enables high throughput screening even for suspended cells with low cell count since the signature microfluidic cell-trapping feature ensures cell preservation in a multiple solution exchange protocol.

Bevacizumab preconditioning followed by Etoposide and Cisplatin is highly effective in treating brain metastases of breast cancer progressing from whole-brain radiotherapy

PURPOSE

We hypothesized that a window period between bevacizumab and cytotoxic agents may enhance drug delivery into tumor tissue through bevacizumab-induced vascular normalization in patients with brain metastases of breast cancer (BMBC).

EXPERIMENTAL DESIGN

A single-arm phase II study was conducted in which BMBC patients refractory to whole-brain radiotherapy (WBRT) were enrolled. In a 21-day cycle, patients received bevacizumab (15 mg/kg) on day 1, which, with a 1-day window period, was followed by etoposide (70 mg/m(2)/day; days 2-4) and cisplatin (70 mg/m(2); day 2; BEEP regimen). The BEEP regimen was administered for a maximum of 6 cycles. The primary endpoint was the central nervous system (CNS)-objective response rate according to volumetric response criteria.

RESULTS

A total of 35 patients were enrolled between January 2011 and January 2013. The median age was 54.3 years (range, 33-75); 19 patients (54.3%) had an Eastern Cooperative Oncology Group performance status of 2 or 3. Twenty-seven patients [77.1%; 95% confidence interval (CI), 59.9-89.6] achieved a CNS-objective response, including 13 patients (37.1%) with a ≥80% volumetric reduction of CNS lesions. With a median follow-up of 16.1 months, the median CNS progression-free survival and overall survival times were 7.3 months (95% CI, 6.5-8.1) and 10.5 months (95% CI, 7.8-13.2), respectively. Common grade 3 or 4 toxicities included neutropenia (30.8%) and infection (21.3%).

CONCLUSIONS

By administering bevacizumab 1 day before etoposide and cisplatin, the BEEP regimen appeared highly effective in BMBC refractory to WBRT. Further study of vascular normalization window concept is warranted.

Deregulated microRNAs in triple-negative breast cancer revealed by deep sequencing

Background

MicroRNAs (miRNAs) are short, non-coding RNA molecules that play critical roles in human malignancy. However, the regulatory characteristics of miRNAs in triple-negative breast cancer, a phenotype of breast cancer that does not express the genes for estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2, are still poorly understood.

Methods

In this study, miRNA expression profiles of 24 triple-negative breast cancers and 14 adjacent normal tissues were analyzed using deep sequencing technology. Expression levels of miRNA reads were normalized with the quantile-quantile scaling method. Deregulated miRNAs in triple-negative breast cancer were identified from the sequencing data using the Student’s t-test. Quantitative reverse transcription PCR validations were carried out to examine miRNA expression levels. Potential target candidates of a miRNA were predicted using published target prediction algorithms. Luciferase reporter assay experiments were performed to verify a putative miRNA-target relationship. Validated molecular targets of the deregulated miRNAs were retrieved from curated databases and their associations with cancer progression were discussed.

Results

A novel 25-miRNA expression signature was found to effectively distinguish triple-negative breast cancers from surrounding normal tissues in a hierarchical clustering analysis. We documented the evidence of seven polycistronic miRNA clusters preferentially harboring deregulated miRNAs in triple-negative breast cancer. Two of these miRNA clusters (miR-143-145 at 5q32 and miR-497-195 at 17p13.1) were markedly down-regulated in triple-negative breast cancer, while the other five miRNA clusters (miR-17-92 at 13q31.3, miR-183-182 at 7q32.2, miR-200-429 at 1p36.33, miR-301b-130b at 22q11.21, and miR-532-502 at Xp11.23) were up-regulated in triple-negative breast cancer. Moreover, miR-130b-5p from the miR-301b-130b cluster was shown to directly repress the cyclin G2 (CCNG2) gene, a crucial cell cycle regulator, in triple-negative breast cancer cells. Luciferase reporter assays showed that miR-130b-5p-mediated repression of CCNG2 was dependent on the sequence of the 3′-untranslated region. The findings described in this study implicate a miR-130b-5p-CCNG2 axis that may be involved in the malignant progression of triple-negative breast cancer.

Conclusions

Our work delivers a clear picture of the global miRNA regulatory characteristics in triple-negative breast cancer and extends the current knowledge of microRNA regulatory network.

Electronic supplementary material

The online version of this article (doi:10.1186/s12943-015-0301-9) contains supplementary material, which is available to authorized users.

Evaluation of a pilot volunteer feeding assistance program: influences on the dietary intakes of elderly hospitalised patients and lessons learnt

OBJECTIVES

Malnutrition is a serious concern in hospitals and is known to be associated with increased complications for patients, increased hospital costs and length of stay. Trained volunteers that assist 'at risk' and malnourished patients at lunch meals have been shown to effectively increase nutritional intake in a suburban hospital in Sydney. The pilot study reported here aimed to evaluate and share learnings from a similar, newly implemented program, comparing energy and macronutrient intakes on days with no volunteer assistance, to days with volunteers.

DESIGN

Dietary intakes were determined by visual estimation of meal trays before and after meals, for two days without volunteers, and two days with volunteer assistance at lunch. Macronutrient and energy intakes were compared and data such as weight, height, diet type and medical history were obtained from medical records. Questionnaires were completed by nurses and volunteers in regards to their views and experiences with the program.

SETTING

Hospital based.

RESULTS

Eight patients (83±4.5 years) participated in the study. When volunteers were present at lunch, the average macronutrient and energy intakes increased, though not statistically significantly. The mean increases were 316 kJ (p=0.175) for energy, 3.1 g (p=0.468) for protein, 1.4 g (p=0.418) for fat and 11.6 g (p=0.084) for carbohydrates. Non-significant increases in macronutrients were also noted for the average daily intakes.

CONCLUSION

Although not statistically significant, energy and macronutrient intakes increased when volunteers were present. The implementation of a volunteer feeding assistance program is one strategy to assist dietary intakes but requires a ready team of volunteers, training, acceptance and significant time to develop.

No increased venous thromboembolism risk in Asian breast cancer patients receiving adjuvant tamoxifen

Tamoxifen is an effective endocrine treatment for early breast cancer (EBC) but increases the risk of venous thromboembolism. Whether Asian EBC patients (pts) bear the same risk when treated with adjuvant tamoxifen is uncertain. EBC pts diagnosed between 2004 and 2009 were selected from a population database in Taiwan. The pts were followed up from the index date to December 31, 2011 to collect events of deep vein thrombosis (DVT) and pulmonary embolism (PE). Cumulative incidence rates and hazard ratios (HRs) were used to compare the risk between pts treated with and without tamoxifen. In addition, comorbidities were included in an adjusted model of the risk of DVT and PE. A total of 28,029 EBC pts, including 17,843 (63.8 %) in the tamoxifen group and 10,155 (36.2 %) in the nontamoxifen group, were analyzed. The 7-year cumulative incidence rates for DVT and PE were 2.58 and 0.32 % in the tamoxifen group and 2.51 and 0.32 % in the nontamoxifen group (P = 0.92 for DVT, P = 0. 65 for PE), respectively. The HR for the nonadjusted and adjusted models showed no differences in DVT and PE risks between the tamoxifen and nontamoxifen groups. The uterine cancer risk was significantly increased in the pts receiving tamoxifen (adjusted HR = 2.79, P < 0.001), suggesting tamoxifen compliance. The risks of developing DVT and PE are not increased in Asian EBC pts receiving adjuvant tamoxifen. Ethnicity differences should be considered when discussing optimal endocrine treatments with EBC pts.

Computer-Aided Strain Evaluation for Acoustic Radiation Force Impulse Imaging of Breast Masses

Acoustic radiation force impulse (ARFI) is a newly developed elastography technique that uses acoustic radiation force to provide additional stiffness information to conventional sonography. A computer-aided diagnosis (CAD) system was proposed to automatically specify the tumor boundaries in ARFI images and quantify the statistical stiffness information to reduce user dependence. The level-set segmentation was used to delineate tumor boundaries in B-mode images, and the segmented boundaries were then mapped to the corresponding area in ARFI images for a gray-scale calculation. A total of 61 benign and 51 malignant tumors were evaluated in the experiment. The CAD system based on the proposed ARFI features achieved an accuracy of 80% (90/112), a sensitivity of 80% (41/51), and a specificity of 80% (49/61), which is significantly better than that of the quantitative B-mode features (p < 0.05). The ARFI features were further combined with the B-mode features, including shape and texture features, to further improve performance (area under the curve [AUC], 0.90 vs. 0.86). In conclusion, the CAD system based on the proposed ARFI features is a promising and efficient diagnostic method.

Multi-dimensional tumor detection in automated whole breast ultrasound using topographic watershed

Automated whole breast ultrasound (ABUS) is becoming a popular screening modality for whole breast examination. Compared to conventional handheld ultrasound, ABUS achieves operator-independent and is feasible for mass screening. However, reviewing hundreds of slices in an ABUS image volume is time-consuming. A computer-aided detection (CADe) system based on watershed transform was proposed in this study to accelerate the reviewing. The watershed transform was applied to gather similar tissues around local minima to be homogeneous regions. The likelihoods of being tumors of the regions were estimated using the quantitative morphology, intensity, and texture features in the 2-D/3-D false positive reduction (FPR). The collected database comprised 68 benign and 65 malignant tumors. As a result, the proposed system achieved sensitivities of 100% (133/133), 90% (121/133), and 80% (107/133) with FPs/pass of 9.44, 5.42, and 3.33, respectively. The figure of merit of the combination of three feature sets is 0.46 which is significantly better than that of other feature sets ( [Formula: see text]). In summary, the proposed CADe system based on the multi-dimensional FPR using the integrated feature set is promising in detecting tumors in ABUS images.