Ki-67 as a controversial predictive and prognostic marker in breast cancer patients treated with neoadjuvant chemotherapy

BACKGROUND: Studies have partly demonstrated the clinical validity of Ki-67 as a predictive marker in the neoadjuvant setting, but the question of the best cut-off points as well as the importance of this marker as a prognostic factor in partial responder/non-responder groups remains uncertain. METHODS: One hundred twenty patients diagnosed with invasive breast cancer and treated with neoadjuvant chemotherapy (NAC) between 2002 and 2013 were retrospectively recruited to this study. The optimal cut-off value for Ki-67 labeling index (LI) to discriminate response to treatment was assessed by receiver operating characteristic (ROC) curve analysis. Kaplan-Meier curve estimation, log-rank test and cox regression analysis were carried out to reveal the association between Ki-67 categories and survival (DMFS = Distant metastases-free survival, OS = Overall survival). RESULTS: Twenty three out of 120 patients (19.2%) achieved pathologic complete remission (pCR), whereas partial remission (pPR) and no response (pNR) to neoadjuvant chemotherapy (NAC) was detected in 60.8% and 20.0%, respectively. The distribution of subtypes showed a significant difference in pathological response groups (p < 0.001). Most of the TNBC cases were represented in pCR group. The most relevant cut-off value for the Ki-67 distinguishing pCR from pNR cases was 20% (p = 0.002). No significant threshold for Ki-67 was found regarding DMFS (p = 0.208). Considering OS, the optimal cut-off point occurred at 15% Ki-67 (p = 0.006). The pPR group represented a significant Ki-67 threshold at 30% regarding OS (p = 0.001). Ki-67 and pPR subgroups were not significantly associated (p = 0.653). For prognosis prediction, Ki-67 at 30% cut-off value (p = 0.040) furthermore subtype (p = 0.037) as well as pathological response (p = 0.044) were suitable to separate patients into good and unfavorable prognosis cohorts regarding OS. However, in multivariate analyses, only Ki-67 at 30% threshold (p = 0.029), and subtype (p = 0.008) were independently linked to OS. CONCLUSIONS: NAC is more efficient in tumors with at least 20% Ki-67 LI. Both Ki-67 LI and subtype showed a significant association with pathological response. Ki-67 LI represented independent prognostic potential to OS in our neoadjuvant patient cohort, while pathological response did not. Additionally, our data also suggest that if a tumor is non-responder to NAC, increased Ki-67 is a poor prognostic marker

The CIN4 chromosomal instability qPCR classifier defines tumor aneuploidy and stratifies outcome in grade 2 breast cancer.

Purpose: Quantifying chromosomal instability (CIN) has both prognostic and predictive clinical utility in breast cancer. In order to establish a robust and clinically applicable gene expression-based measure of CIN, we assessed the ability of four qPCR quantified genes selected from the 70-gene Chromosomal Instability (CIN70) expression signature to stratify outcome in patients with grade 2 breast cancer. Methods: AURKA, FOXM1, TOP2A and TPX2 (CIN4), were selected from the CIN70 signature due to their high level of correlation with histological grade and mean CIN70 signature expression in silico. We assessed the ability of CIN4 to stratify outcome in an independent cohort of patients diagnosed between 1999 and 2002. 185 formalin-fixed, paraffin-embedded (FFPE) samples were included in the qPCR measurement of CIN4 expression. In parallel, ploidy status of tumors was assessed by flow cytometry. We investigated whether the categorical CIN4 score derived from the CIN4 signature was correlated with recurrence-free survival (RFS) and ploidy status in this cohort. Results: We observed a significant association of tumor proliferation, defined by Ki67 and mitotic index (MI), with both CIN4 expression and aneuploidy. The CIN4 score stratified grade 2 carcinomas into good and poor prognostic cohorts (mean RFS: 83.864.9 and 69.4 +- 8.2 months, respectively, p = 0.016) and its predictive power was confirmed by multivariate analysis outperforming MI and Ki67 expression. Conclusions: The first clinically applicable qPCR derived measure of tumor aneuploidy from FFPE tissue, stratifies grade 2 tumors into good and poor prognosis groups

Nottingham prognostic index plus (NPI+) predicts risk of distant metastases in primary breast cancer

The Nottingham prognostic index plus (NPI+) is based on the assessment of biological class combined with established clinicopathologic prognostic variables providing improved patient outcome stratification for breast cancer superior to the traditional NPI. This study aimed to determine prognostic capability of the NPI+ in predicting risk of development of distant disease. A well-characterised series of 1073 primary early-stage BC cases treated in Nottingham and 251 cases from Budapest were immunohistochemically assessed for cytokeratin (Ck)5/6, Ck18, EGFR, oestrogen receptor (ER), progesterone receptor, HER2, HER3, HER4, Mucin 1 and p53 expression. NPI+ biological class and prognostic scores were assigned using individual algorithms for each biological class incorporating clinicopathologic parameters and investigated in terms of prediction of distant metastases-free survival (MFS). The NPI+ identified distinct prognostic groups (PG) within each molecular class which were predictive of MFS providing improved patient outcome stratification superior to the traditional NPI. NPI+ PGs, between series, were comparable in predicting patient outcome between series in luminal A, basal p53 altered and HER2+/ER+ (p > 0.01) tumours. The low-risk groups were similarly validated in luminal B, luminal N, basal p53 normal tumours (p > 0.01). Due to small patient numbers the remaining PGs could not be validated. NPI+ was additionally able to predict a higher risk of metastases at certain distant sites. This study may indicate the NPI+ as a useful tool in predicting the risk of metastases. The NPI+ provides accurate risk stratification allowing improved individualised clinical decision making for breast cancer

Correlation of the value of 18F-FDG uptake, described by SUVmax, SUVavg, metabolic tumour volume and total lesion glycolysis, to clinicopathological prognostic factors and biological subtypes in breast cancer.

OBJECTIVE: The aim of this study was to observe the relationships between different metabolic parameters and clinicopathological features (CPFs) or immunohistochemically defined biological subtypes (IHC-BS) in breast cancer. MATERIALS AND METHODS: Eighty-two women (83 lesions, tumour size >15 mm) underwent PET/computed tomography imaging after a core biopsy. Maximum and average standardized uptake values (SUVmax, SUVavg), metabolic tumour volume (MTV) and total lesion glycolysis (TLG) in the primary tumour were calculated and compared with CPFs and IHC-BS. Tumours with oestrogen receptor (ER) positivity were separately investigated in relation to their progesterone receptor (PR) status. RESULTS: Significant correlation was found between all metabolic parameters and high nuclear grade or ER status or IHC-BS. All parameters were higher in PR(-) and triple-negative cases than in PR(+) and non-triple-negative tumours, and the correlation was significant for most of the metabolic parameters (except for SUVavg in the case of PR status and MTV in the case of triple negativity). Significant correlation was found only for SUVmax regarding the human epidermal growth factor receptor 2 (HER2) status. There was moderate correlation between the Ki67 expression and the SUVmax or SUVavg. All metabolic parameters were higher in ER(+)/PR(-)/HER2(-) lesions compared with ER(+)/PR(+)/HER2(-) cancers. However, ER(+)/PR(-)/HER2(+) tumours had lower SUVmax and SUVavg compared with ER(+)/PR(+)/HER2(+) lesions. CONCLUSION: Our study confirms that the fluorine-18 fluorodeoxyglucose uptake in primary tumour is associated with distinct CPFs or IHC-BS in breast cancer. SUVmax may reflect tumour metabolism more reliably compared with SUVavg, MTV or total lesion glycolysis. Our preliminary results suggest different biological properties in ER(+) tumours with different PR statuses

Presence of cardiomyocytes exhibiting Purkinje-type morphology and prominent connexin 45 immunoreactivity in the myocardial sleeves of cardiac veins

BACKGROUND: Pulmonary vein (PV) myocardium is a known source of atrial fibrillation. A debated question is whether myocardial extensions into caval veins and coronary sinus (CS) have similar properties. No studies have documented specific pacemaker and/or conducting properties for the human extracardiac myocardium. OBJECTIVE: The aim was to characterize the histology and immunohistochemical features of myocardial sleeves in the wall of cardiac veins. METHODS: Sections of 32 human hearts were investigated. Specimens of PVs, superior caval vein (SVC), CS, sinoatrial and atrioventricular nodes and left ventricle were stained with Best's Carmine for selective staining of intracellular glycogen. Anti-connexin (Cx)-45 and Cx43 specific antibodies were used to determine the conduction properties of extracardiac myocardium. RESULTS: Myocardial sleeve was found in the wall of PVs of 15/16 hearts, 21/22 SVCs and 8/8 CSs. Bundles of glycogen positive cardiomyocytes exhibiting pale cytoplasm and peripheral myofibrils were observed in the venous sleeves. Strong Cx45 and weak Cx43 labeling was detected in the extracardiac myocardium. Similar staining pattern was observed at the pacemaker and conduction system, while ventricular myocardium exhibited prominent Cx43 and no Cx45 immunoreactivity. CONCLUSION: Myocardial fibers of PVs, SVC and CS exhibit similar morphology to that of Purkinje fibers and are enriched in glycogen. We provide data for the first time, on the prominent positive staining for Cx45 in the extracardiac myocardium, indicating its potential pacemaker and/or conducting nature

An evaluation of the various aspects of the progress in clinical applications of laser driven ionizing radiation

There has been a vast development of laser-driven particle acceleration (LDPA) using high power lasers. This has initiated by the radiation oncology community to use the dose distribution and biological advantages of proton/heavy ion therapy in cancer treatment with a much greater accessibility than currently possible with cyclotron/synchrotron acceleration. Up to now, preclinical experiments have only been performed at a few LDPA facilities; technical solutions for clinical LDPA have been theoretically developed but there is still a long way to go for the clinical introduction of LDPA. Therefore, to explore the further potential bio-medical advantages of LDPA has pronounced importance. The main characteristics of LDPA are the ultra-high beam intensity, the flexibility in beam size reduction and the potential particle and energy selection whilst conventional accelerators generate single particle, quasi mono-energetic beams. There is a growing number of studies on the potential advantages and applications of Energy Modulated X-ray Radiotherapy, Modulated Electron Radiotherapy and Very High Energy Electron (VHEE) delivery system. Furthermore, the ultra-high space and/or time resolution of super-intense beams are under intensive investigation at synchrotrons (microbeam radiation and very high dose rate (> 40 Gy/s) electron accelerator flash irradiation) with growing evidence of significant improvement of the therapeutic index. Boron Neutron Capture Therapy (BNCT) is an advanced cell targeted binary treatment modality. Because of the high linear energy transfer (LET) of the two particles (7Li and 4He) released by 10BNC reaction, all of the energy is deposited inside the tumour cells, killing them with high probability, while the neighbouring cells are not damaged. The limited availability of appropriate neutron sources, prevent the more extensive exploration of clinical benefit of BNCT. Another boron-based novel binary approach is the 11B-Proton Fusion, which result in the release of three high LET alpha particles. These promising, innovative approaches for cancer therapy present huge challenges for dose calculation, dosimetry and for investigation of the biological effects. The planned LDPA (photons, VHEE, protons, carbon ions) at ELI facilities has the unique property of ultra-high dose rate (> Gy/s-10), short pulses, and at ELI-ALPS high repetition rate, have the potential to develop and establish encouraging novel methods working towards compact hospital-based clinical applications. © 2017 IOP Publishing Ltd and Sissa Medialab srl

BRCA Mutation Related and Claudin-low Breast Cancer: Blood Relatives or Stepsisters?

BACKGROUND BRCA mutation-associated (BRCAmut) breast cancer represents a heterogeneous group displaying certain molecular features. Claudin-low breast cancers (CLBC) overlap with characteristics of BRCAmut tumors; therefore, we have investigated whether these are identical subtypes. METHODS Using public gene expression data, CLDN, CDH1, 9-cell line claudin-low predictor (9CLCLP) and PAM50 expression was evaluated in BRCAmut and BRCA wild-type (BRCAwt) breast cancer cases focusing on their possible overlap with the CLBC subtype. A separate formalin-fixed, paraffin-embedded (FFPE) cohort of 22 BRCAmut and 19 BRCAwt tumor tissues was used for immunohistochemical examination of AR, CD24, CD44, CK5/6, claudin-1, -3, -4 and -7, E-cadherin, EGFR, estrogen receptor (ER), EZH2, HER2, Ki67, p53, progesterone receptor (PgR) and vimentin expression. RESULTS In the data sets, CLDN1 (ROC = 0.785, p < 0.001), CDH1 (ROC = 0.785, p < 0.001), CLDN7 (ROC = 0.723, p < 0.001), CLDN3 (ROC = 0.696, p = 0.020) and CLDN4 (ROC = 0.685, p = 0.027) were expressed at higher level in BRCAmut than BRCAwt tumor tissue. The PAM50 subtype differed from the assigned immunohistochemistry (IHC)-based subtype in 30%. Based on accessible 9CLCLP predictor genes, BRCAmut breast cancer does not display the claudin-low phenotype. Utilizing FFPE samples, claudins were evidently expressed in both BRCAmut and BRCAwt cases. However, at the protein level, only claudin-3 expression was higher in BRCAmut tumors, while claudin-1, -4 and -7 and E-cadherin expression was lower compared to BRCAwt cases. A CD24low/CD44high phenotype was found in BRCAmut tumors upon comparison with BRCAwt cases (p < 0.001 and p = 0.001, respectively). CONCLUSIONS There is a prominent correlation between the genes under focus herein and BRCA mutation status. BRCAmut tumors bear stem cell characteristics displaying a distinct cell adhesion molecule profile characterized by high expression of CDH1 and CLDN4 according to public gene expression data set analysis, and higher claudin-3 expression as detected by IHC; thus, BRCAmut breast carcinomas are not identical with the previously identified claudin-low subtype of breast cancer