OSNA Total Tumor Load for the Prediction of Axillary Involvement in Breast Cancer Patients: Should We use Different Thresholds According to the Intrinsic Molecular Subtype? MOTTO Study.

Aims: To assess the impact of the molecular subtype (MS) on the total number of CK19 mRNA copies in all positive SLN (TTL) threshold, to predict non-SLN affectation, and to compare 5 years progression-free survival (PFS) according to the risk of recurrence (ROR) group by PAM50. Methods: Cohort with infiltrating breast cancer with intra-operative metastatic SLN detected by one-step nucleic acid amplification (OSNA) assay who underwent subsequent ALND. Logistic regression was used to assess a possible interaction between TTL and MS(Triple Negative, Her-2-Enriched, Luminal A, or Luminal B), or hormone receptors (HR: positive or negative) by immunohistochemistry (IMH). Cox regression was used to compare PFS and OS in the 3 ROR groups (high, medium, or low). Results: TTL was predictive of non-SLN affectation in both univariate (OR [95% CI]: 1.72 [1.43, 2.05], P < .001) and multivariate (1.55 [95% CI: 1.04, 2.32], P = .030) models, but MS-IMH or HR-IMH, and their interactions with TTL were not (best multivariate model: HR + main effect OR 1.16 [95% CI: 0.18, 7.64], P = .874; interaction OR: 1.04 [0.7, 1.55], P = .835; univariate model: HR + main effect OR: 1.44 [95% CI: 0.85, 2.44], P = .180). PFS was lower in the high-risk ROR group (81.1%) than in the low-risk group (93.9%) (HR: 3.68 [95 CI: 1.70, 7.94], P < .001). Conclusions: our results do not provide evidence to support the utilization of subtype-specific thresholds for TTL values to make therapeutic decisions on the axilla. The ROR group was predictive of 5 years-PFS.

Predictive and prognostic value of total tumor load in sentinel lymph nodes in breast cancer patients after neoadjuvant treatment using one-step nucleic acid amplification: the NEOVATTL study.

OBJECTIVE: To evaluate the predictive and prognostic value of total tumor load (TTL) in sentinel lymph nodes (SLNs) in patients with infiltrating breast cancer after neoadjuvant systemic therapy (NST). METHODS: This retrospective multicenter study used data from a Spanish Sentinel Lymph Node database. Patients underwent intraoperative SLN biopsy after NST. TTL was determined from whole nodes using a one-step nucleic acid amplification (OSNA) assay and defined as the total sum of CK19 mRNA copies in all positive SLNs. Cox-regression models identified independent predictive variables, which were incorporated into a nomogram to predict axillary non-SLN metastasis, and identified prognostic variables for incorporation into a disease-free survival (DFS) prognostic score. RESULTS: A total of 314 patients were included; most had no lymph node involvement prior to NST (cN0; 75.0% of patients). Most received chemotherapy with or without biologic therapy (91.7%), and 81 patients had a pathologic complete response. TTL was predictive of non-SLN involvement (area under the concentration curve = 0.87), and at a cut-off of 15,000 copies/µL had a negative predictive value of 90.5%. Nomogram parameters included log (TTL + 1), maximum tumor diameter and study-defined NST response. TTL was prognostic of disease recurrence and DFS at a cut-off of 25,000 copies/µL. After a 5-year follow-up, DFS was higher in patients with ≤ 25,000 copies/µL than those with > 25,000 (89.9% vs. 70.0%; p = 0.0017). CONCLUSIONS: TTL > 15,000 mRNA copies/µL was predictive of non-SLN involvement and TTL > 25,000 mRNA copies/µL was associated with a higher risk of disease recurrence in breast cancer patients who had received NST.

The ever-evolving role of pathologists in the management of breast cancer with neoadjuvant treatment: recommendations based on the Spanish clinical experience.

PURPOSE: To compare the current international standards for neoadjuvant systemic therapy (NAST) protocols, and establish consensus recommendations by Spanish breast pathologists; and to look into the Spanish reality of defining pathological complete response in daily practice. MATERIALS AND METHODS: A modified Delphi technique was used to gain consensus among a panel of 46 experts with regard to important issues about NAST specimens, with the objective of standardize handling and analysis of these breast cancer specimens. In addition, a survey was conducted among 174 pathologists to explore the Spanish reality of post-NAST breast cancer specimens handling. RESULTS: Our survey shows that pathologists in Spain follow the same guidelines as their international colleagues and face the same problems and controversies. Among the experts, 94.1% agreed on the recommendation for a pre-treatment evaluation with a core needle biopsy, and 100% of experts agreed on the need of having properly indicated information for the post-NAST surgical specimens. However, only 82.7% of them receive properly labelled specimens and even less receive specimens where markers are identified and the degree of clinical/radiological response is mentioned. Among participants 59.9% were familiar with the residual cancer burden system for post-NAST response quantification, but only 16.1% used it regularly. CONCLUSIONS: Active participation on breast cancer multidisciplinary teams, optimal usage of core needle biopsy for timely and standardized procedures for the diagnostic analysis, and accurate diagnosis of pathological complete response and complete evaluation of the response to NAST need to become the standard practice when handling breast cancer specimens in Spain.

The intra-tumor heterogeneity of cell signaling factors in breast cancer: p4E-BP1 and peIF4E are diffusely expressed and are real potential targets.

Breast cancers and most malignant tumors are composed of heterogeneous tumor cells both at genetic and morphological levels; intra-tumor heterogeneity can be one underlying cause of therapeutic resistance. Classical studies have focused on analyses of the relationship between primary tumors and metastatic dissemination, and on subclone evolution. However, it should be noted that tumor heterogeneity at the level of protein expression (proteomics) has not been yet studied in depth. The differences in protein expression also can play an important role in elucidating the relationship between intra-tumor heterogeneity and resistance to systemic therapy. In fact, in human tumors there is not always a homogeneous expression of many of the crucial factors involved in cell signaling, such as pMAPK, pAKt, pMTOR, even with constitutive oncogenic alterations upstream, such as HER2, PI3 K. Conversely, two of these factors, peIF4E and p4E-BP1, which are downstream, and control protein translation, show a diffuse and strong protein expression. In summary, most of cell signaling factors show a heterogeneous expression, regardless of oncogenic alterations. Tissue heterogeneity could be driven by local factors, including hypoxia. The fact that the phosphorylation of crucial proteins such as 4E-BP1 and eIF4E is observed homogeneously throughout most tumors and are druggable opens the chance to get real potential targets in cancer therapy.

Capturing intra-tumor genetic heterogeneity by de novo mutation profiling of circulating cell-free tumor DNA: a proof-of-principle.

BACKGROUND: Plasma-derived cell-free tumor DNA (ctDNA) constitutes a potential surrogate for tumor DNA obtained from tissue biopsies. We posit that massively parallel sequencing (MPS) analysis of ctDNA may help define the repertoire of mutations in breast cancer and monitor tumor somatic alterations during the course of targeted therapy. PATIENT AND METHODS: A 66-year-old patient presented with synchronous estrogen receptor-positive/HER2-negative, highly proliferative, grade 2, mixed invasive ductal-lobular carcinoma with bone and liver metastases at diagnosis. DNA extracted from archival tumor material, plasma and peripheral blood leukocytes was subjected to targeted MPS using a platform comprising 300 cancer genes known to harbor actionable mutations. Multiple plasma samples were collected during the fourth line of treatment with an AKT inhibitor. RESULTS: Average read depths of 287x were obtained from the archival primary tumor, 139x from the liver metastasis and between 200x and 900x from ctDNA samples. Sixteen somatic non-synonymous mutations were detected in the liver metastasis, of which 9 (CDKN2A, AKT1, TP53, JAK3, TSC1, NF1, CDH1, MML3 and CTNNB1) were also detected in >5% of the alleles found in the primary tumor sample. Not all mutations identified in the metastasis were reliably identified in the primary tumor (e.g. FLT4). Analysis of ctDNA, nevertheless, captured all mutations present in the primary tumor and/or liver metastasis. In the longitudinal monitoring of the patient, the mutant allele fractions identified in ctDNA samples varied over time and mirrored the pharmacodynamic response to the targeted therapy as assessed by positron emission tomography-computed tomography. CONCLUSIONS: This proof-of-principle study is one of the first to demonstrate that high-depth targeted MPS of plasma-derived ctDNA constitutes a potential tool for de novo mutation identification and monitoring of somatic genetic alterations during the course of targeted therapy, and may be employed to overcome the challenges posed by intra-tumor genetic heterogeneity. REGISTERED CLINICAL TRIAL: www.clinicaltrials.gov, NCT01090960.

Prediction of non-sentinel lymph node metastasis in early breast cancer by assessing total tumoral load in the sentinel lymph node by molecular assay.

INTRODUCTION: The one-step nucleic acid amplification (OSNA) is a molecular procedure that yields a semiquantitative result for detection of nodal metastasis. Size of metastasis in the sentinel lymph node (SLN) by conventional histology has been described as a predictive factor for additional axillary metastasis. The objective of this study is to quantify intraoperatively the total tumoral load (TTL) in the positive SLNs assessed by OSNA and to determine whether this TTL predicts non-SLN metastasis in patients with clinically node negative early stage breast cancer. METHODS: 306 patients with cT1-3N0 invasive breast cancer who had undergone intraoperative SLN evaluation by OSNA were included. TTL was defined as the addition of CK19 mRNA copies of each positive SLN (copies/µL). RESULTS: TTL was a predictive factor of additional non-SLN metastasis in the complete axillary lymph node dissection (cALND) (OR, 1.67; 95% CI, 1.18-2.35). In the multivariate analysis, the TTL was a predictor of non-SLN metastasis in HR positive patients (OR, 1.69; 95% CI, 1.19-2.41). In our cohort of patients, with a TTL ≤1.2 × 10(5) copies/µL, there was a specificity of 85.3% and negative predictive value (NPV) of 80%. If we consider only the HR positive patients, with a TTL ≤5 × 10(5) copies/µL there was a specificity of 86.7% and NPV of 83.7%. CONCLUSIONS: TTL assessed by OSNA assay predicts for additional non-SLN metastasis and this intraoperative tool can help guiding decisions on performing a cALND in breast cancer patients.

Dual regulation of Myc by Abl.

The tyrosine kinase c-Abl (or Abl) and the prolyl-isomerase Pin1 cooperatively activate the transcription factor p73 by enhancing recruitment of the acetyltransferase p300. As the transcription factor c-Myc (or Myc) is a known target of Pin1 and p300, we hypothesized that it might be regulated in a similar manner. Consistent with this hypothesis, overexpression of Pin1 augmented the interaction of Myc with p300 and transcriptional activity. The action of Abl, however, was more complex than predicted. On one hand, Abl indirectly enhanced phosphorylation of Myc on Ser 62 and Thr 58, its association with Pin1 and p300 and its acetylation by p300. These effects of Abl were exerted through phosphorylation of substrate(s) other than Myc itself. On the other hand, Abl interacted with the C-terminal domain of Myc and phosphorylated up to five tyrosine residues in its N-terminus, the principal of which was Y74. Indirect immunofluorescence or immunohistochemical staining suggested that the Y74-phosphorylated form of Myc (Myc-pY74) localized to the cytoplasm and coexisted either with active Abl in a subset of mammary carcinomas or with Bcr-Abl in chronic myeloid leukemia. In all instances, Myc-pY74 constituted a minor fraction of the cellular Myc protein. Thus, our data unravel two potential effects of Abl on Myc: first, Abl signaling can indirectly augment acetylation of Myc by p300, and most likely also its transcriptional activity in the nucleus; second, Abl can directly phosphorylate Myc on tyrosine: the resulting form of Myc appears to be cytoplasmic, and its presence correlates with Abl activation in cancer.

A dominant-negative N-terminal fragment of HER2 frequently expressed in breast cancers.

The transmembrane tyrosine kinase HER2 (ErbB2, neu) is a prototypical biomarker for breast cancers and a therapeutic target. Although anti-HER2 therapies are remarkably effective, HER2-positive tumors are heterogeneous and some subtypes do not respond or develop resistance to these therapies. Here we show that H2NTF, a novel N-terminal fragment of HER2, is expressed at variable levels in 60% of the breast cancer samples analyzed. Characterization of H2NTF shows that it is devoid of the tyrosine kinase domain but it readily interacts with full-length HER2 and other HER receptors. As a consequence, H2NTF acts as a dominant-negative, attenuating the signaling triggered by full-length HER receptors. Expression of H2NTF results in resistance to the treatment with low concentrations of trastuzumab in vitro. However, cells expressing H2NTF and non-expressing cells have similar sensitivity to trastuzumab in vivo, indicating that H2NTF/trastuzumab complexes trigger antibody-dependent cell-mediated cytotoxicity.

[The glycemic response to a test breakfast of an enteral diet with fiber and a high starch content in diabetics treated with insulin and oral antidiabetics]. / Respuesta glucémica a un desayuno de prueba con una dieta enteral con fibra y alto contenido en almidón en diabéticos tratados con insulina y antidiabéticos orales.

An enteral nutrition preparation appeared recently on the Spanish market specifically for diabetic patients. It is a normocaloric and normoproteic formula of low osmolarity, rich in soluble fibre and slow-absorption carbohydrates such as fructose and starch, following the classic norms of the American Diabetics Association. The glycemic response was examined at 0, 30, 60 and 120 minutes following the ingestion of 250 cc of Precitene Diabet as breakfast for 40 diabetic patients, half treated with oral antidiabetic substances (DMado) and the other half with insulin (DMins). In both groups, the greatest glycemic increase was at 60 minutes. In the DMado patients, the increase at 60 minutes (70 mg/dl) was not significantly different from that considered by Skyler as acceptable. The same occurred at 120 minutes (40 mg/dl). In the DMins patients, the glycemic increase at 60 minutes was 27 +/- 29 mg/dl, more than that considered acceptable by Skyler (p 0.0006). After 120 minutes this difference was also greater than the acceptable level, by 41 +/- 38 mg/dl (p 0.0002). In conclusion, it may be considered that, for DMado patients, glycemic control remains within the postprandial limits considered to be "acceptable" so that no treatment modification is felt necessary in the administration of enteral nutrition with Precitene Diabet. The glycemic response in the DMins patients was higher than "acceptable", calling for rapid insulin supplements to their habitual NPH insulin doses.