Strategies for subtypes--dealing with the diversity of breast cancer: highlights of the St. Gallen International Expert Consensus on the Primary Therapy of Early Breast Cancer 2011

Oncology biomarkers: discovery, validation, and clinical use

OBJECTIVES

To discuss the discovery, validation, and clinical use of multiple types of biomarkers.

DATA SOURCES

Medical literature and published guidelines.

CONCLUSION

Formal validation of biomarkers should include both retrospective analyses of well-characterized samples as well as a prospective clinical trial in which the biomarker is tested for its ability to predict the presence of disease or the efficacy of a cancer therapy.

IMPLICATIONS FOR NURSING PRACTICE

Biomarker development is complicated, with very few biomarker discoveries leading to clinically useful tests. Nurses should understand how a biomarker was developed, including the sensitivity and specificity before applying new biomarkers in the clinical setting.

The molecular profile of luminal B breast cancer

Molecular profiling studies have found that estrogen receptor-positive (ER+) human breast cancers are comprised of at least two distinct diseases with differing biologies. With the advent of DNA microarrays, global gene expression patterns were used to define the luminal A and luminal B subtypes of ER+ breast cancer, with luminal B cancers showing a more aggressive phenotype including substantially worse outcomes in patients. The luminal B subtype designation could be considered a surrogate for those ER+ tumors having low progesterone receptors, high proliferation, high grade, and predicted poor response to hormone therapy. While they express estrogen receptors, luminal B cancers do not show a corresponding expression of estrogen-regulated genes, and may therefore rely upon alternative pathways for growth. At the molecular level, luminal B cancers appear dramatically distinct from luminal A cancers, at the levels of gene expression, gene copy, somatic mutation, and DNA methylation; luminal B cancers are also genetically and genomically altered to a greater extent than luminal A cancers. While, in the clinical setting, luminal B is typically regarded as an ER+, hormone-sensitive disease, more research is needed into how to better treat it. Comprehensive profiling initiatives, such as The Cancer Genome Atlas, have recently provided us a catalog of mutated or copy altered genes, from which new therapeutic targets could potentially be mined. Candidate pathways that might be targeted in luminal B include those involving growth factor receptors, including HER2 and EGFR, as well as PI3K/Akt/mTor.

Morphological heterogeneity of the simultaneous ipsilateral invasive tumor foci in breast carcinoma: a retrospective study of 418 cases of carcinomas

The aim of this paper was to assess whether the morphological appearance (i.e. histological tumor type and histological grade) of simultaneous invasive breast carcinoma foci is heterogeneous, since it is known that adjuvant therapy is established according to these parameters. Patients with simultaneous breast tumors in which only the features of the largest neoplastic focus are reported could thus be undertreated. A retrospective study of 418 cases of breast carcinomas was conducted over a 3-year period. The histological tumor types and histological grades of multifocal/multicentric carcinomas in each tumor focus were compared, and mismatches among foci were recorded. Ninety-one of the 418 cases reviewed had multiple carcinomas (21.77%). A comparison between multiple synchronous tumor foci revealed that their histological type was different in 12.08% of the cases. Mismatches among foci were also observed in 9.89% of the cases when evaluating the histological grade, and 5 out of 9 additional tumor foci with a different grade from the largest (index) tumor (55.55%) displayed a higher grade compared to the index tumor. Since the histological tumor type and histological grade of the individual foci may vary considerably within the same tumor and the additional foci may be of higher grade than the index tumor, we believe that reporting morphologic parameters with more unfavorable characteristics in addition to the parameters of the index tumor is imperative.

Highlights of the EORTC St. Gallen International Expert Consensus on the primary therapy of gastric, gastroesophageal and oesophageal cancer - differential treatment strategies for subtypes of early gastroesophageal cancer

The 1st St. Gallen EORTC Gastrointestinal Cancer Conference 2012 Expert Panel clearly differentiated treatment and staging recommendations for the various gastroesophageal cancers. For locally advanced gastric cancer (≥T3N+), the preferred treatment modality was pre- and postoperative chemotherapy. The majority of panel members would also treat T2N+ or even T2N0 tumours with a similar approach mainly because pretherapeutic staging was considered highly unreliable. It was agreed that adenocarcinoma of the gastroesophageal junction (AEG) is classified best according to Siewert et al. Preoperative radiochemotherapy (RCT) is the preferred treatment for AEG type I and II tumours. For AEG type III, i.e. tumours which may be considered as gastric cancer, perioperative chemotherapy is the majority approach. For resectable squamous cell cancer of the oesophagus a clear majority recommended radiochemotherapy followed by surgery as optimal approach, irrespective of tumour size. In contrast, definitive RCT was judged appropriate for advanced tumours with extended lymph node involvement (N2) or for cancers of the upper oesophagus. Additional recommendations are presented on the use of endosonography, PET-CT scan and laparoscopy for staging and on the preferred approach to surgery.

Neoadjuvant chemotherapy in breast cancer-insights from the German experience

New insights into neoadjuvant treatment of breast cancer have shown that the prognostic value of pathological complete response has to be rated differently according to subtype. Whereas in triple-negative, HER2-positive (non-luminal) and luminal B (HER2-negative) patients with a pCR after neoadjuvant chemotherapy show a significantly better outcome than patients without a pCR, this prognostic impact cannot be seen in patients with luminal A or luminal B (HER2-positive) tumors. Patients can therefore only avoid an initially high-risk prognosis if they have a pCR of these first mentioned subtypes. For patients with those tumors or with high Ki-67 levels in residual disease, new treatment options have to be found. Contrarily, response-guided chemotherapy, i.e., changing the regimen in case of no early response or intensification in case of early response, showed significant survival advantages only in the latter group. Strategies are currently being developed on how locoregional treatment can be reduced in patients with a pathological complete response. These aim to reduce the extent of surgery or even avoid surgery completely.

Subcutaneous versus intravenous administration of (neo)adjuvant trastuzumab in patients with HER2-positive, clinical stage I-III breast cancer (HannaH study): a phase 3, open-label, multicentre, randomised trial

BACKGROUND

A subcutaneous formulation of trastuzumab has been developed, offering potential improvements in patient convenience and resource use compared with the standard intravenous infusion of the drug. We compared the pharmacokinetic profile, efficacy, and safety of the subcutaneous and intravenous formulations in patients with HER2-positive early breast cancer.

METHODS

The HannaH study was a phase 3, randomised, international, open-label, trial in the (neo)adjuvant setting. Patients with HER2-positive, operable, locally advanced or inflammatory breast cancer were randomly assigned to eight cycles of neoadjuvant chemotherapy administered concurrently with trastuzumab every 3 weeks either intravenously (8 mg/kg loading dose, 6 mg/kg maintenance dose) or subcutaneously (fixed dose of 600 mg); 1:1 ratio. Chemotherapy consisted of four cycles of docetaxel (75 mg/m(2)) followed by four cycles of fluorouracil (500 mg/m(2)), epirubicin (75 mg/m(2)), and cyclophosphamide (500 mg/m(2)), every 3 weeks. After surgery, patients continued trastuzumab to complete 1 year of treatment. Coprimary endpoints were serum trough concentration (C(trough)) at pre-dose cycle 8 before surgery (non-inferiority margin for the ratio between groups of 0·80) and pathological complete response (pCR; non-inferiority margin for the difference between groups of -12·5%), analysed in the per-protocol population. This study is registered with ClinicalTrials.gov, number NCT00950300.

FINDINGS

299 patients were randomly assigned to receive intravenous trastuzumab and 297 to receive subcutaneous trastuzumab. The geometric mean presurgery C(trough) was 51·8 μg/mL (coefficient of variation 52·5%) in the intravenous group and 69·0 μg/mL (55·8%) in the subcutaneous group. The geometric mean ratio of C(trough) subcutaneous to C(trough) intravenous was 1·33 (90% CI 1·24-1·44). 107 (40·7%) of 263 patients in the intravenous group and 118 (45·4%) of 260 in the subcutaneous group achieved a pCR. The difference between groups in pCR was 4·7% (95% CI -4·0 to 13·4). Thus subcutaneous trastuzumab was non-inferior to intravenous trastuzumab for both coprimary endpoints. The incidence of grade 3-5 adverse events was similar between groups. The most common of these adverse events were neutropenia (99 [33·2%] of 298 patients in the intravenous group vs 86 [29·0%] of 297 in the subcutaneous group), leucopenia (17 [5·7%] vs 12 [4·0%]), and febrile neutropenia (10 [3·4%] vs 17 [5·7%]). However, more patients had serious adverse events in the subcutaneous group (62 [21%] of 297 patients) than in the intravenous group (37 [12%] of 298); the difference was mainly attributable to infections and infestations (24 [8·1%] in the subcutaneous group vs 13 [4·4%] in the intravenous group). Four adverse events led to death (one in the intravenous group and three in the subcutaneous group), all of which occurred during the neoadjuvant phase. Of these, two--both in the subcutaneous group--were deemed to be treatment related.

INTERPRETATION

Subcutaneous trastuzumab, administered over about 5 min, has a pharmacokinetic profile and efficacy non-inferior to standard intravenous administration, with a similar safety profile to intravenous trastuzumab, and therefore offers a valid treatment alternative.

FUNDING

F Hoffmann-La Roche.

Risk factors associated with recurrence after nipple-sparing mastectomy for invasive and intraepithelial neoplasia

BACKGROUND

To identify risk factors of recurrence in a large series of patients with breast cancer who underwent a nipple-sparing mastectomy (NSM).

PATIENTS AND METHODS

Breast-related recurrences and local recurrences (LR) in the breast and the nipple areola complex (NAC) were studied. Cumulative incidences of events were estimated through competing risk analysis. Multivariate Cox regression models were also applied.

RESULTS

We identified 934 consecutive NSM patients during 2002-2007. Median follow-up was 50 months. In 772 invasive carcinoma patients, the rate of LR in the breast and in the NAC was 3.6% and 0.8%, respectively. In the 162 patients with intraepithelial neoplasia, the rate of LR in the breast and in the NAC was 4.9% and 2.9%, respectively. The significant risk factors of LR in the breast for the group A were grade, overexpression/amplification of HER2/neu and breast cancer molecular subtype Luminal B. In group B, the risk factors of LR in the breast and in the NAC were age (<45 years), absence of estrogen receptors, grade, HER2/neu overexpression and high Ki-67.

CONCLUSIONS

The LR rate after NSM in our series was low. Biological features of disease and young age should be taken into account when considering NSM in breast cancer patients.

A method to measure clinical practice patterns of breast cancer genomic diagnostics in health systems

Personalized genomic diagnostics, often in combination with targeted therapeutics, have become an important component of clinical oncologic practice over the last decade. However, there is a dearth of studies examining utilization of specific genomic diagnostics and their influence on clinical practice patterns in health systems. In order to begin to explore and understand the clinical utility of particular genomic diagnostics in current use, we developed an instrument to collect data on utilization and clinical practice patterns in health systems. We focused our efforts on gene-expression profiling (GEP) assays, particularly on a commonly used GEP in breast cancer: Oncotype DX® (Genomic Health, Inc., CA, USA). This article presents a method we have developed for the retrospective collection of data on the utilization of GEP among breast cancer patients of a real-world, real-time health system.

A critical review why assessment of steroid hormone receptors in breast cancer should be quantitative

Steroid receptors have been around in the field of breast cancer for decades now. Still, controversy remains on how best to report steroid receptors. In this review, we will convince the reader why benefits outweigh pitfalls, when reporting steroid receptors in a quantitative rather than qualitative way. Summarizing decades of research in this field, we will explore the evidence why quantitative reporting is superior in all settings (neoadjuvant, adjuvant and metastatic settings). Furthermore, we will also summarize different staining methods, definitions and pitfalls that have shown to be important points of discussion in earlier debates. Although the molecular unraveling of breast cancer in the past decade has revolutionized the way we think about breast cancer, we should not easily abandon the classical pathological variables such as steroid receptors in favor of molecular tools.

Late radiation toxicity after intraoperative radiotherapy (IORT) for breast cancer: results from the randomized phase III trial TARGIT A

The randomized phase III trial TARGIT A showed non-inferiority regarding local control after intraoperative radiotherapy (IORT 20 Gy which was followed by whole breast radiotherapy (WBRT) in patients with risk factors only) in comparison to standard WBRT (50-56 Gy) after breast-conserving surgery in selected patients. This is the first analysis of long-term toxicities in the setting of TARGIT. Between 02/2002 and 12/2008, 305 patients were treated within TARGIT A (Arm A: n = 34 IORT, n = 20 IORT + WBRT for risk factors; Arm B WBRT: n = 55) or received IORT as a planned boost (control group: n = 196) at a single center. Toxicity was assessed according to the LENT SOMA scales. No significant differences were seen between Arm A and Arm B regarding fibrosis, breast edema, retraction, ulceration, lymphedema, hyperpigmentation, and pain. Arm A had significantly less telangiectases compared to Arm B (p = 0.049). In the subanalysis (Arm A IORT vs. Arm A IORT + WBRT vs. Arm B), fibrosis had a cumulative rate of 5.9 versus 37.5 versus 18.4 %, respectively (38.2 % IORT boost control group), at 3 years. No telangiectases were seen after IORT alone (0 % Arm A IORT vs. 17.5 % Arm A IORT + WBRT vs. 17.7 % Arm B). The hazard ratio of higher grade toxicity as first event was 0.46 (95 % CI, 0.26-0.83) for Arm A IORT as compared to Arm B (p = 0.010). No recurrences were seen after a median follow-up of 40 months (Arm A) and 42 months (Arm B). With its very low chronic skin toxicity rates and outstanding long-term results regarding toxicity and local control, IORT with 50 kV X-rays is a safe and effective method for treatment of selected breast cancer patients.

Cytologic features of triple-negative breast carcinoma

BACKGROUND

Triple-negative breast cancer (TNBC) is distinct from other breast cancers, because the tumor cells lack estrogen and progesterone receptors (hormone receptors) and also are negative for human epidermal growth factor receptor 2 (HER2). They comprise a heterogeneous group of tumors with various histologic features and clinical behaviors. High-grade, invasive ductal carcinoma not otherwise specified is the most frequent type, and a substantial fraction of TNBCs belongs to the basal-like tumor type. The purpose of this study was to determine whether some cytologic features could predict the triple phenotype of breast carcinoma.

METHODS

Fine-needle aspiration cytology samples of 62 TNBCs were compared with samples of 82 hormone receptor-positive, high-grade, invasive carcinomas (HRBC) and with samples of 33 hormone receptor-negative, HER2 positive, invasive carcinomas (HER2BC) for the following cytomorphologic features: cellularity, necrosis, lymphocytes, syncytial clusters, tubular/ductal-like clusters, large bare nuclei, streaming within the clusters, and calcifications. Moreover, single cell features, such as cellular borders, cytoplasm, cytoplasmic vacuoles, nuclear pleomorphism, nucleoli, and type of chromatin pattern, were evaluated. Descriptive analyses and 2 multivariate regression models were performed to compare TNBC, HRBC, and HER2BC and to identify the cytologic factors that were associated with tumor type.

RESULTS

TNBCs were more likely to have an abundant necrotic background, many lymphocytes, many syncytial clusters, and ill defined cell borders than non-TNBCs. A tubular/ductal pattern was observed only rarely in TNBCs. Multivariate logistic analysis indicated a 90.8% probability of identifying TNBC versus HRBC by the following cytologic variables: lymphocytes, ill defined cell borders and syncytial clusters, tubular/ductal clusters, cytoplasmic vacuoles, and cellular pleomorphism; whereas there was a 77.5% probability of identifying TNBC rather than HER2BC by the following variables: cellularity, ill defined cellular borders and syncytial clusters, and tubular/ductal clusters.

CONCLUSIONS

Although TNBCs embrace a heterogeneous group of tumors, in this study, they exhibited some common cytologic features that can help to distinguish them from other high-grade breast carcinomas in daily practice.

Luminal A and luminal B (HER2 negative) subtypes of breast cancer consist of a mixture of tumors with different genotype

Background

The St Gallen International Expert Consensus 2011 has proposed a new classification system for breast cancer. The purpose of this study was to elucidate the relationship between the breast cancer subtypes determined by the new classification system and genomic characteristics.

Methods

Invasive breast cancers (n = 363) were immunohistochemically classified as follows: 111 (30.6%) as luminal A, 95 (26.2%) as luminal B (HER2 negative), 69 (19.0%) as luminal B (HER2 positive), 41 (11.3%) as HER2, and 47 (12.9%) as basal-like subtypes.

Results

The high expression of Ki-67 antigen was detected in 236 tumors; no cases of luminal A subtype showed high expression of the Ki-67 antigen, but more than 85% of tumors of the other subtypes showed high expression. In addition, DNA ploidy and chromosomal instability (CIN) were assessed using imaging cytometry and FISH, respectively. In this series, 336 (92.6%) tumors consisted of 129 diploid/CIN- and 207 aneuploid/CIN + tumors. Diploid/CIN- and aneuploid/CIN+ features were detected in 64.9% and 27.9% of luminal A, 41.1% and 49.5% of luminal B (HER2-), 11.6% and 81.2% of luminal B (HER2+), 4.9% and 90.2% of HER2, and 17.0% and 76.6% of basal-like subtypes, respectively. Unlike the luminal B (HER2+), HER2 and basal-like subtypes, the luminal A and luminal B (HER2-) subtypes were heterogeneous in terms of DNA ploidy and CIN.

Conclusions

It is reasonable to propose that the luminal A and luminal B (HER2-) subtypes should be further divided into two subgroups, diploid/CIN- and aneuploid/CIN+, based on their underlying genomic status.

Dual Effect of Metformin on Breast Cancer Proliferation in a Randomized Presurgical Trial

Purpose

Metformin is associated with reduced breast cancer risk in observational studies in patients with diabetes, but clinical evidence for antitumor activity is unclear. The change in Ki-67 between pretreatment biopsy and post-treatment surgical specimen has prognostic value and may predict antitumor activity in breast cancer.

Patients and Methods

After tumor biopsy, we randomly allocated 200 nondiabetic women with operable breast cancer to either metformin 850 mg/twice per day (n = 100) or placebo (n = 100). The primary outcome measure was the difference between arms in Ki-67 after 4 weeks adjusted for baseline values.

Results

Overall, the metformin effect on Ki-67 change relative to placebo was not statistically significant, with a mean proportional increase of 4.0% (95% CI, −5.6% to 14.4%) 4 weeks apart. However, there was a different drug effect depending on insulin resistance (homeostasis model assessment [HOMA] index > 2.8, fasting glucose [mmol/L] × insulin [mU/L]/22.5; Pinteraction = .045), with a nonsignificant mean proportional decrease in Ki-67 of 10.5% (95% CI, −26.1% to 8.4%) in women with HOMA more than 2.8 and a nonsignificant increase of 11.1% (95% CI, −0.6% to 24.2%) with HOMA less than or equal to 2.8. A different effect of metformin according to HOMA index was noted also in luminal B tumors (Pinteraction = .05). Similar trends to drug effect modifications were observed according to body mass index (P = .143), waist/hip girth-ratio (P = .058), moderate alcohol consumption (P = .005), and C-reactive protein (P = .080).

Conclusion

Metformin before surgery did not significantly affect Ki-67 overall, but showed significantly different effects according to insulin resistance, particularly in luminal B tumors. Our findings warrant further studies of metformin in breast cancer with careful consideration to the metabolic characteristics of the study population.

Survey of the application of the korean clinical practice recommendations on breast cancer treatment: the utility of the korean breast cancer society guidelines

This survey was performed to analyze the usability of the third edition of the Korean breast cancer clinical practice guidelines (KBCCPG) in clinical practice. We made a questionnaire composed of 18 general and 82 specific questions regarding benign breast disease (B; 1 question); non-invasive disease (N; 12 questions); early-stage disease (E; 26 questions); advanced disease (A; 24 questions); and metastatic (M) breast cancer-related problems (19 questions). A total of 100 questionnaires, with a link to an online survey, were delivered via e-mail to over 700 members of the Korean Breast Cancer Society (KBCS), and associated academy members, over 20 days between 26th February and 16th May 2010. Out of 270 respondents who read the e-mail, 96 answered the questionnaire. Participants included 87 surgical oncologists, 5 radiation oncologists, 2 oncoplastic surgeons, 1 pathologist, and 1 medical oncologist. The third KBCCPG were perceived as differing from the second guidelines in terms of the level of clinical evidence required before choosing a recommendation. For the progress of the KBCCPG, the guideline committee should try to reinforce all courses of guideline development with several elements including data from clinical trials of Korean breast cancer patients, securing a multidisciplinary approach, developing consistent and reasonable processes for each step of the revision of the guidelines, induction of liberal scientific and ethical discussion about all issues with all KBCS members. The cost-effectiveness of healthcare and the logical development of the KBCCPG would also be ensured. Timely updates of the clinical guidelines for breast cancer treatment are essential to facilitate optimal decision-making in daily practice, and to ensure adequate patient feedback.

Omission of axillary dissection after a positive sentinel node dissection may influence adjuvant chemotherapy indications in operable breast cancer patients

BACKGROUND

This study was designed to evaluate how the omission of axillary dissection would have altered the indication for adjuvant chemotherapy (ACT) in patients with early breast cancer submitted to conservative surgery with one or two positive sentinel lymph nodes (SLNs).

METHODS

We identified 321 women in our institutional database who fulfilled the characteristics. All underwent completion axillary lymph node dissection (AD). Each case was blindly reviewed by our breast team in two rounds, and the total number of positive lymph nodes was disclosed only in the second. At each round, the panel chose between: (1) recommend, (2) discuss, (3) do not recommend ACT. Changes between round 1 and 2 were studied by the marginal homogeneity test. Exploratory logistic regression analyses were performed to study predictors of non-SLN involvement and of changes in the indication for ACT.

RESULTS

AD revealed non-SLNs metastases in 96 patients (30 %). Fifty-two patients (16 %) had their initial indication changed at round 2 (p < 0.001). Most of the changes were toward ACT (83 %), and all except two occurred in patients with immunohistochemically defined luminal A and luminal B/HER2-negative tumors. In these two subgroups, a Ki67 above the median value (21 %) was the only independent predictor of no change in the indication to ACT at round 2.

CONCLUSIONS

Omission of AD in patients with one or two positive SLNs may change the indication to ACT in a significant proportion of patients with hormone receptor-positive/HER2-negative tumors. All implications should be taken into account before abandoning AD, including a possible biologically tailored surgical approach.

Study on the skip metastasis of axillary lymph nodes in breast cancer and their relation with Gli1 expression

The skip metastasis (SM) of axillary lymph nodes (ALN) in breast cancer is an important phenomenon which is crucial to determine the correct choice of surgical resection. The mechanism of SM of ALN is unclear. Gli1 protein is a core epithelial-to-mesenchymal transition (EMT) regulatory factor that plays essential roles in both development and disease processes and has been associated with metastasis in carcinomas. The aim of this study was to investigate the clinicopathological characteristics of SM and evaluate the significance of Gli1 expression in breast cancer patients with metastasis of ALN. Clinicopathological data from 1,037 female breast cancer patients who underwent radical mastectomy were retrospectively reviewed. In this study, an SM was defined as level I absence but level II and/or level III involvement. The expression of Gli1 was evaluated by immunohistochemistry in 102 non-SM cases with positive nodes and 33 SM cases. In univariate analysis, we found that pN category, TNM stage, intrinsic subtypes and Gli1 expression was significant risk factor of SM. Further logistic regression analysis revealed that luminal A cases had a lower risk of SM relative to luminal B 1 (HER2 negative) cases. Further multivariate analysis revealed that Gli1 expression and numbers of positive lymph nodes were the independent factors which associated with SM. Collectively, Breast cancer with SM of ALN associated with the intrinsic subtype of the luminal B1. Gli1 expression related with the procession of breast cancer with SM, which can be used as a predictor of SM of ALN in breast cancer.

Menopausal status and adjuvant hormonal therapy for breast cancer patients: a practical guideline

Breast cancer is the most common malignancy amongst women in the developed world. For patients with hormone-sensitive breast cancer eligible for adjuvant hormonal therapy, it is important to know if the ovaries are (still) functional or not. Indeed, the choice for a specific adjuvant hormonal treatment depends on the menopausal status of an individual woman. The currently available measures to determine the menopausal status are conflicting. Until better measures become available, we propose a practical guideline enabling an optimal choice of adjuvant hormonal therapy for women with a hormone receptor positive breast cancer taking into account uncertainties about their menopausal status.

Analysis of clinically relevant values of Ki-67 labeling index in Japanese breast cancer patients

BACKGROUND

It has become important to standardize the methods of Ki-67 evaluation in breast cancer patients, especially those used in the interpretation and scoring of immunoreactivity. Therefore, in this study, we examined the Ki-67 immunoreactivity of breast cancer surgical specimens processed and stained in the same manner in one single Japanese institution by counting nuclear immunoreactivity in the same fashion.

METHODS

We examined 408 Japanese breast cancers with invasive ductal carcinoma and studied the correlation between Ki-67 labeling index and ER/HER2 status and histological grade of breast cancer. We also analyzed overall survival (OS) and disease-free survival (DFS) of these patients according to individual Ki-67 labeling index.

RESULTS

There were statistically significant differences of Ki-67 labeling index between ER positive/HER2 negative and ER positive/HER2 positive, ER negative/HER2 positive or ER negative/HER2 negative, and ER positive/HER2 positive and ER negative/HER2 negative groups (all P < 0.001). There were also statistically significant differences of Ki-67 labeling index among each histological grade (P < 0.001, respectively). As for multivariate analyses, Ki-67 labeling index was strongly associated with OS (HR 39.12, P = 0.031) and DFS (HR 10.85, P = 0.011) in ER positive and HER2 negative breast cancer patients. In addition, a statistically significant difference was noted between classical luminal A group and "20 % luminal A" in DFS (P = 0.039) but not between classical luminal A group and "25 % luminal A" (P = 0.105).

CONCLUSIONS

A significant positive correlation was detected between Ki-67 labeling index and ER/HER2 status and histological grades of the cases examined in our study. The suggested optimal cutoff point of Ki-67 labeling index is between 20 and 25 % in ER positive and HER2 negative breast cancer patients.

Strategy for SRM-based verification of biomarker candidates discovered by iTRAQ method in limited breast cancer tissue samples

Since LC-MS-based quantitative proteomics has become increasingly applied to a wide range of biological applications over the past decade, numerous studies have performed relative and/or absolute abundance determinations across large sets of proteins. In this study, we discovered prognostic biomarker candidates from limited breast cancer tissue samples using discovery-through-verification strategy combining iTRAQ method followed by selected reaction monitoring/multiple reaction monitoring analysis (SRM/MRM). We identified and quantified 5122 proteins with high confidence in 18 patient tissue samples (pooled high-risk (n=9) or low-risk (n=9)). A total of 2480 proteins (48.4%) of them were annotated as membrane proteins, 16.1% were plasma membrane and 6.6% were extracellular space proteins by Gene Ontology analysis. Forty-nine proteins with >2-fold differences in two groups were chosen for further analysis and verified in 16 individual tissue samples (high-risk (n=9) or low-risk (n=7)) using SRM/MRM. Twenty-three proteins were differentially expressed among two groups of which MFAP4 and GP2 were further confirmed by Western blotting in 17 tissue samples (high-risk (n=9) or low-risk (n=8)) and Immunohistochemistry (IHC) in 24 tissue samples (high-risk (n=12) or low-risk (n=12)). These results indicate that the combination of iTRAQ and SRM/MRM proteomics will be a powerful tool for identification and verification of candidate protein biomarkers.

A phase II trial to assess efficacy and safety of afatinib in extensively pretreated patients with HER2-negative metastatic breast cancer

Afatinib (BIBW 2992) is an ErbB-family blocker that irreversibly inhibits signaling from all relevant ErbB-family dimers. Afatinib has demonstrated preclinical activity in human epidermal growth factor receptor HER2 (ErbB2)-positive and triple-negative xenograft models of breast cancer, and clinical activity in phase I studies. This was a multicenter phase II study enrolling patients with HER2-negative metastatic breast cancer progressing following no more than three lines of chemotherapy. No prior epidermal growth factor receptor-targeted therapy was allowed. Patients received 50-mg afatinib once daily until disease progression. Tumor assessment was performed at every other 28-day treatment course. The primary endpoint was clinical benefit (CB) for ≥4 treatment courses in triple-negative (Cohort A) metastatic breast cancer (TNBC) and objective responses measured by Response Evaluation Criteria in Solid Tumors in patients with HER2-negative, estrogen receptor-positive, and/or progesterone receptor-positive breast cancer (Cohort B). Fifty patients received treatment, including 29 patients in Cohort A and 21 patients in Cohort B. No objective responses were observed in either cohort. Median progression-free survival was 7.4 and 7.7 weeks in Cohorts A and B, respectively. Three patients with TNBC had stable disease for ≥4 treatment courses, one of them for 12 courses (median 26.3 weeks; range 18.9–47.9 weeks). The most frequently observed afatinib-associated adverse events (AEs) were gastrointestinal and skin-related side effects, which were manageable by symptomatic treatment and dose reductions. Afatinib pharmacokinetics were comparable to those observed in previously reported phase I trials. In conclusion, afatinib had limited activity in HER2-negative breast cancer. AEs were generally manageable and mainly affected the skin and the gastrointestinal tract.

Distribution, clinicopathologic features and survival of breast cancer subtypes in Southern China

Breast cancer research and treatment by different subtypes is an inevitable trend. We investigated the clinicopathologic features and outcomes of different breast cancer subtypes in Southern China. A total of 5809 patients with invasive ductal carcinomas were identified. Immunohistochemical (IHC) markers for estrogen receptor (ER), progesterone receptor (PR), Her2/neu, and Ki-67 proliferation index were used to classify cases into five molecular subtypes. Clinicopathologic characteristics and survival rates were analyzed retrospectively. Of all patients, 31.1% were luminal A subtype, 30.4% luminal B (high Ki-67), 13.1% luminal B (Her2/neu+), 9.0% Her2/neu and 16.5% triple negative subtype. Luminal B (high Ki-67) presented primarily in premenopausal patients with the lowest average age (43.0 years). Her2/neu positive tumors were more closely associated with aggressive features including increased tumor size, positive lymph node status and lymphvascular invasion (LVI). Triple negative subtype was characterized by poorer histologic grade. Her2/neu positive cases had presented the worst 5-year disease-free survival (DFS) and overall survival (OS). Multivariate analyses of OS and DFS suggested that there were different negative prognostic factors for the five subtypes. The benefit of the cyclophosphamide, methotrexate, and 5-fluorouracil (5FU) (CMF) regimen was equal to that of anthracycline-based and Taxane-based regimens for patients with luminal A subtype and triple negative subtype, but inferior to anthracycline-based and Taxane-based regimens for those with two luminal B subtypes and Her2/neu subtype. The prognostic significance of traditional markers may differ among subtypes. This study revealed the distinct clinicopathologic characteristics, systemic therapy benefits, prognostic factors and survival rate among different breast cancer subtypes.

PAM50 assay and the three-gene model for identifying the major and clinically relevant molecular subtypes of breast cancer

It has recently been proposed that a three-gene model (SCMGENE) that measures ESR1, ERBB2, and AURKA identifies the major breast cancer intrinsic subtypes and provides robust discrimination for clinical use in a manner very similar to a 50-gene subtype predictor (PAM50). However, the clinical relevance of both predictors was not fully explored, which is needed given that a ~30 % discordance rate between these two predictors was observed. Using the same datasets and subtype calls provided by Haibe-Kains and colleagues, we compared the SCMGENE assignments and the research-based PAM50 assignments in terms of their ability to (1) predict patient outcome, (2) predict pathological complete response (pCR) after anthracycline/taxane-based chemotherapy, and (3) capture the main biological diversity displayed by all genes from a microarray. In terms of survival predictions, both assays provided independent prognostic information from each other and beyond the data provided by standard clinical–pathological variables; however, the amount of prognostic information was found to be significantly greater with the PAM50 assay than the SCMGENE assay. In terms of chemotherapy response, the PAM50 assay was the only assay to provide independent predictive information of pCR in multivariate models. Finally, compared to the SCMGENE predictor, the PAM50 assay explained a significantly greater amount of gene expression diversity as captured by the two main principal components of the breast cancer microarray data. Our results show that classification of the major and clinically relevant molecular subtypes of breast cancer are best captured using larger gene panels.

Breast Cancer 2012 - New Aspects

Treatment options as well as the characteristics for therapeutic decisions in patients with primary and advanced breast cancer are increasing in number and variety. New targeted therapies in combination with established chemotherapy schemes are broadening the spectrum, however potentially promising combinations do not always achieve a better result. New data from the field of pharmacogenomics point to prognostic and predictive factors that take not only the properties of the tumour but also inherited genetic properties of the patient into consideration. Current therapeutic decision-making is thus based on a combination of classical clinical and modern molecular biomarkers. Also health-economic aspects are more frequently being taken into consideration so that health-economic considerations may also play a part. This review is based on information from the recent annual congresses. The latest of these are the 34th San Antonio Breast Cancer Symposium 2011 and the ASCO Annual Meeting 2012. Among their highlights are the clinically significant results from the CLEOPATRA, BOLERO-2, EMILIA and SWOG S0226 trials on the therapy for metastatic breast cancer as well as further state-of-the-art data on the adjuvant use of bisphosphonates within the framework of the ABCSG-12, ZO-FAST, NSABP-B34 and GAIN trials.

Impact of immunohistochemistry-based molecular subtype on chemosensitivity and survival in patients with breast cancer following neoadjuvant chemotherapy

Purpose

Pathologic complete response (pCR) has been suggested as a surrogate prognostic indicator in breast cancer patients treated with neoadjuvant chemotherapy. We assessed whether the likelihood of pCR and survival is associated with the immunohistochemistry-based molecular subtypes.

Methods

We retrospectively analyzed the records of 276 patients with breast cancer who received neoadjuvant chemotherapy between January 2000 and January 2010. Patients were classified into four molecular subtypes based on the immunohistochemistry profiles of estrogen receptor, progesterone receptor, and HER2/neu. Logistic regression was used to analyze variables associated with pCR.

Results

The pCR was achieved in 45 patients (16.3%). The triple negative subtype was an independent predictive factor for pCR (odds ratio, 3.21; 95% confidence interval, 1.20-8.56; p=0.020), and the ERBB-2 subtype showed a trend for higher pCR rates (odds ratio, 3.03; 95% confidence interval, 0.93-9.89; p=0.067) compared with the luminal A subtype. In 99 patients with HER2/neu-positive breast cancer, pCR rates were higher in those who received trastuzumab (31.7%) than those treated with conventional chemotherapy regimens (17.2%, p=0.023). The pCR was significantly associated with prolonged progression-free survival (p=0.008). The triple negative subgroup had shorter progression-free survival (p=0.001) and overall survival (p=0.001) than the other subgroups.

Conclusion

We demonstrated that the triple negative and ERBB-2 subtypes are more likely to obtain pCR when neoadjuvant chemotherapy is given, compared to the luminal A subtype. Despite the high pCR rate, the triple negative subtype showed worse survival outcomes, paradoxically, primarily due to patients who had residual disease.

Association between body mass index and breast cancer intrinsic subtypes in Japanese women

The purpose of this study was to examine the association between body mass index (BMI) and breast cancer intrinsic subtypes in Japanese women. A more complete understanding of the subtypes of breast cancer may elucidate the mechanisms affecting the etiology and mortality associated with each subtype. Tumor data on 531 invasive breast cancer cases subtyped by estrogen receptor, progesterone receptor and human epidermal growth factor receptor 2 (Her2) status were obtained [luminal A, luminal B, triple-negative (TN) and Her2-type]. Demographics (age at diagnosis, menopausal status and BMI) were collected from medical records. Case-only odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using logistic regression, adjusting for age at diagnosis. Of the 531 cases, 333 (62.7%) were luminal A, 85 (16.0%) were luminal B, 43 (8.1%) were Her2-type and 70 (13.2%) were TN. Compared with luminal A cases, premenopausal TN cases were more likely to be obese (OR, 4.11; 95% CI, 1.10–14.40), while postmenopausal TN cases were more likely to be underweight (OR, 3.14; 95% CI, 1.19–8.01). Premenopausal luminal B cases were likely to be underweight or obese, while luminal B and Her2-type cases were likely to be underweight. In the present study, significant heterogeneity of associations between BMI and tumor subtypes was observed. Breast cancer subtypes may have various etiologies associated with each subtype.

Reproductive history and breast cancer risk

The fact that reproductive factors have significant influence on the risk of breast cancer is well known. Early age of first full-term birth is highly protective against late-onset breast cancers, but each pregnancy, including the first one, increases the risk of early-onset breast cancer. Estradiol and progesterone induce receptor activator of NF-kappa B ligand (RANKL) in estrogen receptor (ER)- and progesterone receptor (PgR)-positive luminal cells. RANKL then acts in a paracrine fashion on the membranous RANK of ER/PgR-negative epithelial stem cells of the breast. This reaction cascade is triggered by chorionic gonadotropin during the first trimester of pregnancy and results in the morphological and functional development of breast tissue. On the other hand, the administration of non-steroidal anti-inflammatory drugs in the early steps of weaning protects against tumor growth through reduction of the acute inflammatory reaction of post lactation remodeling of breast tissue. This is experimental evidence that may explain the short-term tumor-promoting effect of pregnancy. The protective effect of prolonged breast feeding may also be explained, at least in a part, by a reduced inflammatory reaction due to gradual weaning. Delay of first birth together with low parity and short duration of breast feeding are increasing social trends in developed countries. Therefore, breast cancer risk as a result of reproductive factors will not decrease in these countries in the foreseeable future. In this review, the significance of reproductive history with regard to the risk of breast cancers will be discussed, focusing on the age of first full-term birth and post lactation involution of the breast.

Stromal genes add prognostic information to proliferation and histoclinical markers: a basis for the next generation of breast cancer gene signatures

BACKGROUND

First-generation gene signatures that identify breast cancer patients at risk of recurrence are confined to estrogen-positive cases and are driven by genes involved in the cell cycle and proliferation. Previously we induced sets of stromal genes that are prognostic for both estrogen-positive and estrogen-negative samples. Creating risk-management tools that incorporate these stromal signatures, along with existing proliferation-based signatures and established clinicopathological measures such as lymph node status and tumor size, should better identify women at greatest risk for metastasis and death.

METHODOLOGY/PRINCIPAL FINDINGS

To investigate the strength and independence of the stromal and proliferation factors in estrogen-positive and estrogen-negative patients we constructed multivariate Cox proportional hazards models along with tree-based partitions of cancer cases for four breast cancer cohorts. Two sets of stromal genes, one consisting of DCN and FBLN1, and the other containing LAMA2, add substantial prognostic value to the proliferation signal and to clinical measures. For estrogen receptor-positive patients, the stromal-decorin set adds prognostic value independent of proliferation for three of the four datasets. For estrogen receptor-negative patients, the stromal-laminin set significantly adds prognostic value in two datasets, and marginally in a third. The stromal sets are most prognostic for the unselected population studies and may depend on the age distribution of the cohorts.

CONCLUSION

The addition of stromal genes would measurably improve the performance of proliferation-based first-generation gene signatures, especially for older women. Incorporating indicators of the state of stromal cell types would mark a conceptual shift from epithelial-centric risk assessment to assessment based on the multiple cell types in the cancer-altered tissue.

AKT-aro and HER2-aro, models for de novo resistance to aromatase inhibitors; molecular characterization and inhibitor response studies

Aromatase inhibitors (AI) are currently the first line therapy for estrogen receptor (ER)-positive postmenopausal women. De novo AI resistance is when a patient intrinsically does not respond to an AI therapy as well as other targeted endocrine therapy. To characterize this type of resistance and to examine potential therapies for treatment, we have generated two cell models for de novo resistance. These models derive from MCF-7 cells that stably overexpress aromatase and Akt (AKT-aro) or HER2 (HER2-aro). Evaluation of these cell lines revealed that the activities of aromatase and ER were inhibited by AI and ICI 187280 (ICI) treatment, respectively; however, cell growth was resistant to therapy. Proliferation in the presence of the pure anti-estrogen ICI, indicates that these cells do not require ER for cell growth and distinguishes these cells from the acquired AI resistant cells. We further determined that the HSP90 inhibitor 17-DMAG suppressed the growth of the AI-resistant cell lines studied. Our analysis revealed 17-DMAG-mediated decreased expression of growth promoting signaling proteins. It was found that de novo AI resistant AKT-aro and HER2-aro cells could not be resensitized to letrozole or ICI by treatment with 17-DMAG. In summary, we have generated two cell lines which display the characteristics of de novo AI resistance. Together, these data indicate the possibility that HSP90 inhibitors may be a viable therapy for endocrine therapy resistance although additional clinical evaluation is needed.

Feasibility of prior administration of cyclophosphamide in TC combination treatment

BACKGROUND

TC (docetaxel 75 mg/m(2) and cyclophosphamide 600 mg/m(2) q3w) combination is used for neoadjuvant/adjuvant chemotherapy in primary breast cancer. The incidence of allergic reaction is reportedly more common in patients who receive docetaxel before cyclophosphamide. This study aims to determine the significance of cyclophosphamide and docetaxel administration sequence.

METHODS

Prospective analysis was performed of 49 consecutive patients treated with TC for stage I-IIB breast cancer from March 2010 to June 2011. Premedication was administered with granisetron, dexamethasone, and chlorpheniramine. Patient charts were reviewed for completion rate and adverse events. Two-tailed Fisher exact test was used to evaluate adverse events between prior cyclophosphamide and prior docetaxel.

RESULTS

Of 49 patients, 26 received docetaxel prior to cyclophosphamide and 23 received cyclophosphamide before docetaxel. There were no differences in patient characteristics between the two groups. Completion rates were 95.6 % in the prior cyclophosphamide group, and 100 % in the prior docetaxel group. The relative dose intensities of docetaxel and cyclophosphamide were 94.5 and 94.8 % in the prior cyclophosphamide group, and 98.5 and 98.7 % in the prior docetaxel group (p < 0.01). In the prior cyclophosphamide group, severe neutropenia occurred in 96 % of patients, but in only 46 % of patients in the prior docetaxel group (p < 0.01). Significantly fewer cases of skin eczema (27 versus 61 %), nausea (8 versus 48 %), stomatitis (23 versus 61 %), and diarrhea (4 versus 30 %) were observed in the prior docetaxel group as compared with the prior cyclophosphamide group (p < 0.01). Decreased incidences of fatigue (50 versus 65 %) and edema (19 versus 35 %) were found in the prior docetaxel group (p < 0.05). No difference was observed in allergic reaction or neuropathy between the two groups.

CONCLUSION

Patients receiving cyclophosphamide prior to docetaxel were at increased risk of several toxicities as compared with patients receiving docetaxel prior to cyclophosphamide in TC combination therapy.

Immunohistochemical Ki67 labeling index has similar proliferation predictive power to various gene signatures in breast cancer

The objective of this study was to examine the association between the immunohistochemical Ki67 labeling index (IHC Ki67), Ki67 mRNA expression level, and first-generation gene signatures in a cohort of breast cancer patients. We assessed associations between IHC Ki67 and first-generation gene signatures in a panel of 39 tumor samples, using an oligonucleotide microarray. Gene expression analyses included Ki67 alone (MKi67), 21-gene signature, mitosis kinome score signature, and genomic grade index. Correlation coefficients were calculated by Spearman's rank correlation test. In all cases, IHC Ki67, MKi67, and three genetic markers were highly correlated (ρ, 0.71-0.97). Estrogen receptor (ER)-positive cases showed strong correlations between IHC Ki67 and other signatures (ρ, 0.79-0.83). The ER-negative cases showed slightly lower correlations (ρ, 0.58-0.73). In ER-positive cases, the low IHC Ki67 group showed significantly longer relapse-free survival than the high IHC Ki67 group (P = 0.007). This difference was confirmed by multivariate analysis. Our data indicate that IHC Ki67 shows similar predictive power for proliferation in ER-positive cancers as genomic markers. Further study of IHC Ki67 is needed to define prognostic factors and predictive factors for chemotherapy using central laboratory assessment.

Predictions of the pathological response to neoadjuvant chemotherapy in patients with primary breast cancer using a data mining technique

Nomogram, a standard technique that utilizes multiple characteristics to predict efficacy of treatment and likelihood of a specific status of an individual patient, has been used for prediction of response to neoadjuvant chemotherapy (NAC) in breast cancer patients. The aim of this study was to develop a novel computational technique to predict the pathological complete response (pCR) to NAC in primary breast cancer patients. A mathematical model using alternating decision trees, an epigone of decision tree, was developed using 28 clinicopathological variables that were retrospectively collected from patients treated with NAC (n = 150), and validated using an independent dataset from a randomized controlled trial (n = 173). The model selected 15 variables to predict the pCR with yielding area under the receiver operating characteristics curve (AUC) values of 0.766 [95 % confidence interval (CI)], 0.671-0.861, P value < 0.0001) in cross-validation using training dataset and 0.787 (95 % CI 0.716-0.858, P value < 0.0001) in the validation dataset. Among three subtypes of breast cancer, the luminal subgroup showed the best discrimination (AUC = 0.779, 95 % CI 0.641-0.917, P value = 0.0059). The developed model (AUC = 0.805, 95 % CI 0.716-0.894, P value < 0.0001) outperformed multivariate logistic regression (AUC = 0.754, 95 % CI 0.651-0.858, P value = 0.00019) of validation datasets without missing values (n = 127). Several analyses, e.g. bootstrap analysis, revealed that the developed model was insensitive to missing values and also tolerant to distribution bias among the datasets. Our model based on clinicopathological variables showed high predictive ability for pCR. This model might improve the prediction of the response to NAC in primary breast cancer patients.

Biological characterization and selection criteria of adjuvant chemotherapy for early breast cancer: experience from the Italian observational NEMESI study

Background

International treatment guidelines recommend administration of adjuvant chemotherapy in early breast cancer based on clinical, prognostic and predictive parameters.

Methods

An observational study (NEMESI) was conducted in 63 Italian oncology centres in patients with early breast cancer. Age, performance status, concomitant disease, menopausal status, histology, tumor dimension (pT), axillary lymph node status (pN), grading (G), estrogen and progesterone receptor (ER and PgR), proliferative index (ki67 or MIB-1), human epidermal growth factor receptor 2 (HER2) and type of adjuvant treatment were recorded. The primary objective of the study was to define parameters influencing the decision to prescribe adjuvant chemotherapy and the type of chemotherapy.

Results

Data for 1894 patients were available. 69.0% postmenopausal, 67.0% pT1, 22.3% pTmic/pT1a/pT1b, 61.0% pN0, 48.7% luminal A, 18.1% luminal B, 16.1% HER2 positive, 8.7% triple negative, 8.4% unknown. 57.8% received adjuvant chemotherapy: 38.1% of luminal A, 67.3% luminal B, 88.2% HER2-positive, 97.6% triple negative. Regimens administered: 9.1% CMF-like, 48.8% anthracyclines, 38.4% anthracyclines plus taxanes, 3.7% taxanes alone. Increasing pT/pN and, marginally, HER2-positive were associated with the prescription of anthracyclines plus taxanes. Suboptimal schedules (CMF-like or AC/EC or FEC-75) were prescribed in 37.3% receiving chemotherapy, even in HER2-positive and triple negative disease (36.5% and 34.0%, respectively).

Conclusions

This study showed an overprescription of adjuvant chemotherapy for early breast cancer, particularly referred to luminal A. pT, pN and, marginally, HER2 were the principal determinants for the choice of chemotherapy type. Suboptimal chemotherapy regimens were adopted in at least one third of HER2-positve and triple negative.

Her2 negative luminal breast carcinoma and Ki-67 evaluation

AIM

To determine the degree of inter-observer variability in defining the percentage of Ki-67 immunohistochemical expression in breast carcinoma cases and to investigate the validity of using the cut-point of 14% for the administration of adjuvant treatment in luminal B (Her2 negative) carcinomas.

MATERIALS AND METHODS

99 ER, PR positive, Her2 negative breast carcinomas were consecutively selected from the Pathology files of "IASO" Women's Hospital. Ki-67 immunostaining was evaluated by four pathologists from four different institutions.

RESULTS

Concerning the whole study group, the inter-observer agreement was substantial. Subgroup analysis upon the cases were at least one observer evaluated Ki-67 as being less than 14% showed that the inter-observer agreement was reduced to fair. Further analysis revealed that both below and above the clinicopathological limit of 14%, stands a "grey zone" of about ±7%, in which inter-observer agreement is weak.

CONCLUSION

The administration of cytotoxic therapy in ER, PR positive, Her2 negative breast carcinomas featuring a Ki-67 labeling index of around 14, should be considered with caution. Probably decision-making should also take under consideration the whole morphological and biological profile of each tumor.

Importance of assessing CK19 immunostaining in core biopsies in patients subjected to sentinel node study by OSNA

Analysis of sentinel lymph node (SLN) by means of One-Step Nucleic Acid Amplification (OSNA) is being used increasingly as a very sensitive and quick method for intraoperative axillary staging in patients with breast cancer. This molecular diagnostic assay detects the expression level of cytokeratin 19 (CK19), a luminal epithelial cell marker broadly expressed in most breast carcinomas and not normally found in lymph nodes. Almost all breast cancers express this cytoskeleton protein, but some breast tumors have been found to lose the expression of CK19. CK19 immunostaining in core biopsies has been recommended in selecting patients eligible for OSNA analysis because SLNs with metastatic involvement by CK19-negative breast cancers may result in a false negative result by OSNA. However, the real frequency of CK19-negative breast cancer has to be elucidated. In this study, we have assessed the frequency and molecular profile of CK19-negative breast carcinomas in three series of cases. The first is a prospective series of 197 breast carcinomas, 111 of which were subjected to SLN evaluation by OSNA. The second is a retrospective series of 41 triple-negative (TN) breast carcinomas, and the third is a retrospective series of 68 breast cancer patients (matched core biopsies and metastatic lymph nodes) that had been evaluated by conventional procedures before the OSNA methodology was adopted in our institution. Our results not only demonstrate that lack of expression of CK19 is infrequent in breast cancers but also that performing CK19 immunohistochemical staining is important on diagnostic core biopsies in taking the decision of using OSNA methodology in the evaluation of sentinel nodes in breast cancer patients.

mTOR inhibitors in the management of hormone receptor-positive breast cancer: the latest evidence and future directions

BACKGROUND

There is an unmet therapeutic need in endocrine-resistant, hormone receptor (HR)-positive, human epidermal growth factor receptor 2-negative advanced breast cancer (BC). Preclinical studies support the hypothesis that the mammalian target of rapamycin (mTOR) inhibition could potentially overcome resistance to endocrine therapy.

MATERIALS AND METHODS

A literature review regarding BC and mTOR inhibitors was undertaken. The reference lists from retrieved manuscripts were reviewed to identify further studies.

RESULTS

Phase II studies have reported that the combination of mTOR inhibitors with endocrine therapy shows efficacy in patients with advanced disease that progressed after treatment with aromatase inhibitors. The recent findings of the phase III BOLERO-2 confirmed that everolimus in combination with exemestane significantly improved progression-free survival and response rate, with a manageable safety profile.

CONCLUSIONS

The addition of everolimus to exemestane for women with HR-positive metastatic BC is now considered a new therapeutic strategy. However, a word of caution should be added regarding toxic effects, which might limit practical use and compliance. It is essential that clinicians are educated about key recommendations for toxicity management and specific guideline dose modifications. Additional research efforts with the addition of these compounds in the early-stage setting is greatly needed to improve the survival of patients with HR-positive BC.

Adjuvant chemotherapy of pT1a and pT1b breast carcinoma: results from the NEMESI study

BACKGROUND

The prognosis of pT1a-pT1b breast cancer (BC) used to be considered very good, with a 10-y RFS of 90%. However, some retrospective studies reported a 10-y RFS of 81%-86% and suggested benefit from adjuvant systemic therapy.

METHODS

To evaluate the variables that determined the choice of adjuvant chemotherapy and the type of chemotherapy delivered in pT1a-pT1b BC, we analysed the small tumours enrolled in the NEMESI study.

RESULTS

Out of 1,894 patients with pathological stage I-II BC enrolled in NEMESI, 402 (21.2%) were pT1a-pT1b. Adjuvant chemotherapy was delivered in 127/402 (31.59%). Younger age, grading G3, high proliferative index, ER-negative and HER2-positive status were significantly associated with the decision to administer adjuvant chemotherapy. An anthracycline without taxane regimen was administered in 59.1% of patients, anthracycline with taxane in 24.4%, a CMF-like regimen in 14.2% and taxane in 2.4%. Adjuvant chemotherapy was administered in 88.4% triple-negative and 73.46% HER2-positive pT1a-pT1b BC. Adjuvant trastuzumab was delivered in 30/49 HER2-positive BC (61.2%).

CONCLUSIONS

Adjuvant chemotherapy was delivered in 31.59% T1a-pT1b BC treated at 63 Italian oncological centres from January 2008 to June 2008. The choice to deliver chemotherapy was based on biological prognostic factors. Anthracycline-based chemotherapy was administered in 83.5% patients.

Aurora kinase A outperforms Ki67 as a prognostic marker in ER-positive breast cancer

Background:

Proliferation has emerged as a major prognostic factor in luminal breast cancer. The immunohistochemical (IHC) proliferation marker Ki67 has been most extensively investigated but has not gained widespread clinical acceptance.

Methods:

We have conducted a head-to-head comparison of a panel of proliferation markers, including Ki67. Our aim was to establish the marker of the greatest prognostic utility. Tumour samples from 3093 women with breast cancer were constructed as tissue microarrays. We used IHC to detect expression of mini-chromosome maintenance protein 2, Ki67, aurora kinase A (AURKA), polo-like kinase 1, geminin and phospho-histone H3. We used a Cox proportional-hazards model to investigate the association with 10-year breast cancer-specific survival (BCSS). Missing values were resolved using multiple imputation.

Results:

The prognostic significance of proliferation was limited to oestrogen receptor (ER)-positive breast cancer. Aurora kinase A emerged as the marker of the greatest prognostic significance in a multivariate model adjusted for the standard clinical and molecular covariates (hazard ratio 1.3; 95% confidence interval 1.1–1.5; P=0.005), outperforming all other markers including Ki67.

Conclusion:

Aurora kinase A outperforms other proliferation markers as an independent predictor of BCSS in ER-positive breast cancer. It has the potential for use in routine clinical practice.

Definition and impact of pathologic complete response on prognosis after neoadjuvant chemotherapy in various intrinsic breast cancer subtypes

PURPOSE

The exact definition of pathologic complete response (pCR) and its prognostic impact on survival in intrinsic breast cancer subtypes is uncertain.

METHODS

Tumor response at surgery and its association with long-term outcome of 6,377 patients with primary breast cancer receiving neoadjuvant anthracycline-taxane-based chemotherapy in seven randomized trials were analyzed.

RESULTS

Disease-free survival (DFS) was significantly superior in patients with no invasive and no in situ residuals in breast or nodes (n = 955) compared with patients with residual ductal carcinoma in situ only (n = 309), no invasive residuals in breast but involved nodes (n = 186), only focal-invasive disease in the breast (n = 478), and gross invasive residual disease (n = 4,449; P < .001). Hazard ratios for DFS comparing patients with or without pCR were lowest when defined as no invasive and no in situ residuals (0.446) and increased monotonously when in situ residuals (0.523), no invasive breast residuals but involved nodes (0.623), and focal-invasive disease (0.727) were included in the definition. pCR was associated with improved DFS in luminal B/human epidermal growth factor receptor 2 (HER2) -negative (P = .005), HER2-positive/nonluminal (P < .001), and triple-negative (P < .001) tumors but not in luminal A (P = .39) or luminal B/HER2-positive (P = .45) breast cancer. pCR in HER2-positive (nonluminal) and triple-negative tumors was associated with excellent prognosis.

CONCLUSION

pCR defined as no invasive and no in situ residuals in breast and nodes can best discriminate between patients with favorable and unfavorable outcomes. Patients with noninvasive or focal-invasive residues or involved lymph nodes should not be considered as having achieved pCR. pCR is a suitable surrogate end point for patients with luminal B/HER2-negative, HER2-positive (nonluminal), and triple-negative disease but not for those with luminal B/HER2-positive or luminal A tumors.