Predicting Patients Found to Have Malignancy at Nipple Duct Surgery

Introduction

The unexpected diagnosis of breast cancer following total duct excision is distressing for patients. Despite advances in radiology and the description of suspicious nipple discharge, pre-operative diagnosis of malignancy still evades us. The aim of this study was to review the pathological findings of total duct excision and microdochectomy with reference to pre-operative symptoms, ultrasound, or mammographic findings and identify features associated with increased likelihood of malignant disease.

Methods

Data were collected retrospectively of all patients who underwent total duct excision surgery in a single centre (2011-2017). Pre-operative demographics, symptoms, and imaging findings were recorded and correlated with subsequent pathology.

Results

214 patients underwent total duct excision; data were available for 211. Median age was 53 years. 175/211 (82.9%) patients had benign pathology (duct ectasia, papilloma without atypia, fibrocystic change) on final histological examination, 21/211 (10%) had "risk" lesions (papilloma with atypia, atypical ductal hyperplasia), and 15/211 (7.1%) had malignancy (ductal carcinoma in situ). Of the 15 patients with malignant lesions, 6/15 (40%) had normal imaging (M1, U1). 71/211 (33.6%) had normal imaging (M1, U1): 60/71 (84.5%) had benign disease, 5/71 (7%) had "risk" lesions, and 6/71 (8.5%) had malignant lesions. 83/211 (39.3%) patients presented with bloody discharge: 64/83 (77.1%) had benign pathology, 9/83 (10.8%) risk, and 10/83 (12%) malignancy. 38/211 (18%) patients presented with non-bloody discharge: 32/38 (84.2%) had benign disease, 4/38 (10.5%) risk, and 2/38 (5.3%) malignant lesions.

Conclusion

Neither imaging nor presenting symptoms correlate with the likelihood of malignant disease being present at final pathology. Even with advances in pre-operative diagnosis, total duct excision remains an essential diagnostic and therapeutic procedure.

A prospective comparison of ER, PR, Ki67 and gene expression in paired sequential core biopsies of primary, untreated breast cancer

BACKGROUND

Sequential biopsy of breast cancer is used to assess biomarker effects and drug efficacy. The preoperative "window of opportunity" setting is advantageous to test biomarker changes in response to therapeutic agents in previously untreated primary cancers. This study tested the consistency over time of paired, sequential biomarker measurements on primary, operable breast cancer in the absence of drug therapy.

METHODS

Immunohistochemistry was performed for ER, PR and Ki67 on paired preoperative/operative tumor samples taken from untreated patients within 2 weeks of each other. Microarray analysis on mRNA extracted from formalin fixed paraffin embedded cores was performed using Affymetrix based arrays on paired core biopsies analysed using Ingenuity Pathway Analysis (IPA) and Gene Set Analysis (GSA).

RESULTS

In 41 core/resection pairs, the recognised trend to lower ER, PR and Ki67 score on resected material was confirmed. Concordance for ER, PR and Ki67 without changing biomarker status (e.g. ER+ to ER-) was 90, 74 and 80 % respectively. However, in 23 paired core samples (diagnostic core v on table core), Ki67 using a cut off of 13.25 % was concordant in 22/23 (96 %) and differences in ER and PR immunohistochemistry by Allred or Quickscore between the pairs did not impact hormone receptor status. IPA and GSA demonstrated substantial gene expression changes between paired cores at the mRNA level, including reduced expression of ER pathway analysis on the second core, despite the absence of drug intervention.

CONCLUSIONS

Sequential core biopsies of primary breast cancer (but not core versus resection) was consistent and is appropriate to assess the effects of drug therapy in vivo on ER, PR and Ki67 using immunohistochemistry. Conversely, studies utilising mRNA expression may require non-treatment controls to distinguish therapeutic from biopsy differences.

Effects of metformin on breast cancer cell proliferation, the AMPK pathway and the cell cycle

AIM

The aim of this study was to compare the effects and mechanisms of action of metformin on estrogen receptor (ER)-positive and ER-negative breast cancer cell lines.

METHODS

The anti-proliferative effects of metformin, and of the direct activator of adenosine monophosphate-activated protein kinase (AMPK), A-769662, on MCF-7 (ER-positive) and MDA-MB-231 (ER-negative) breast cancer cell lines were evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide, a yellow tetrazole) assays. Fluorescence-activated cell sorting was also used to examine the effect of metformin on the cell cycle. Finally, phosphorylation of the metformin target AMPK, and of its potential downstream targets including acetyl-CoA carboxylase (ACC), p53, p70-S6K and Raptor, was examined using immunoblotting.

RESULTS

Metformin and A-769662 caused significant, concentration-dependent suppression of cell proliferation with G1 cell cycle arrest in both MCF-7 and MDA-MB-231 cells. The proliferation suppression effect was more profound in MCF-7 cells. A concentration-dependent phosphorylation of AMPK was detected following metformin treatment, as was phosphorylation of ACC in both cell lines, but not p53, p70-S6k or Raptor.

CONCLUSION

Metformin acts as a growth inhibitor in both ER-positive and ER-negative breast cancer cells in vitro, and arrests cells in G1 phase, particularly in the ER-positive MCF-7 cells. The effect is likely to be mediated by AMPK activation, in part by inhibition of fatty acid synthesis via ACC phosphorylation.

Abstract PD03-02: Evidence for the anti-cancer action of metformin mediated via tumor AMPK, Akt and Ki67, in a preoperative window of opportunity trial

Background: Metformin reduces the overall risk of cancer incidence by 31%, improves cancer-related mortality and enhances response to neoadjuvant chemotherapy in type 2-diabetics receiving metformin. There is evidence that metformin works through activation of Adenosine Monophosphate Protein Kinase (AMPK), an energy-sensing kinase that maintains cellular energy homeostasis. In a pre-operative window-of-opportunity randomized trial we have demonstrated that metformin significantly reduces proliferation and blunts the insulin response in primary operable breast cancer. This study further analysed cancer tissue from the trial to dissect the molecular mechanisms involved.

Methodology: Non-diabetic women with operable invasive breast cancer were randomised to receive pre-operative metformin or no drug. Forty seven patients had core biopsy at diagnosis then were randomized to metformin (metformin 500mg o.d. for 1 week increased to 1g b.d for a further week continued to surgery) or no drug, and 2 weeks later had core biopsy at surgery. Insulin receptor, phospho-AMPK (pAMPK), phospho-Akt (pAkt) and Ki67 immunohistochemistry was performed on formalin-fixed paraffin-embedded cores and scored blinded to treatment. Paired t-test was used for analysis.

Results: Significant up-regulation of pAMPK (p = 0.04) and down-regulation of pAkt (p = 0.04) in metformin treated patients was demonstrated compared to the control group. No change in insulin receptor expression was identified but, as previously reported, there was a fall in ki67. Changes were independent of Body Mass Index. Seven patients (7/24) receiving metformin withdrew because of gastro-intestinal upset and were excluded from the immunohistochemical analyses.

Conclusion: These findings suggest that metformin works in vivo in breast cancer patients via up-regulation of tumor pAMPK and down-regulation of pAkt and proliferation. Since down-regulation of pAMPK is a feature of breast cancer, this suggests mechanistic evidence for the therapeutic effect of metformin.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr PD03-02.

Histological evaluation of AMPK signalling in primary breast cancer

Background

AMP-activated protein kinase (AMPK) acts as a cellular fuel gauge that responds to energy stress by suppressing cell growth and biosynthetic processes, thus ensuring that energy-consuming processes proceed only if there are sufficient metabolic resources. Malfunction of the AMPK pathway may allow cancer cells to undergo uncontrolled proliferation irrespective of their molecular energy levels. The aim of this study was to examine the state of AMPK phosphorylation histologically in primary breast cancer in relation to clinical and pathological parameters.

Methods

Immunohistochemistry was performed using antibodies to phospho-AMPK (pAMPK), phospho-Acetyl Co-A Carboxylase (pACC) an established target for AMPK, HER2, ERα, and Ki67 on Tissue Micro-Array (TMA) slides of two cohorts of 117 and 237 primary breast cancers. The quick score method was used for scoring and patterns of protein expression were compared with clinical and pathological data, including a minimum 5 years follow up.

Results

Reduced signal, compared with the strong expression in normal breast epithelium, using a pAMPK antibody was demonstrated in 101/113 (89.4%) and 217/236 (91.9%) of two cohorts of patients. pACC was significantly associated with pAMPK expression (p = 0.007 & p = 0.014 respectively). For both cohorts, reduced pAMPK signal was significantly associated with higher histological grade (p = 0.010 & p = 0.021 respectively) and axillary node metastasis (p = 0.061 & p = 0.039 respectively). No significant association was found between pAMPK and any of HER2, ERα, or Ki67 expression, disease-free survival or overall survival.

Conclusion

This study extends in vitro evidence through immunohistochemistry to confirm that AMPK is dysfunctional in primary breast cancer. Reduced signalling via the AMPK pathway, and the inverse relationship with histological grade and axillary node metastasis, suggests that AMPK re-activation could have therapeutic potential in breast cancer.

A candidate molecular signature associated with tamoxifen failure in primary breast cancer

Introduction

Few markers are available that can predict response to tamoxifen treatment in estrogen receptor (ER)-positive breast cancers. Identification of such markers would be clinically useful. We attempted to identify molecular markers associated with tamoxifen failure in breast cancer.

Methods

Eighteen initially ER-positive patients treated with tamoxifen requiring salvage surgery (tamoxifen failure [TF] patients) were compared with 17 patients who were disease free 5 years after surgery plus tamoxifen adjuvant therapy (control patients). cDNA microarray, real-time quantitative PCR, and immunohistochemistry on tissue microarrays were used to generate and confirm a gene signature associated with tamoxifen failure. An independent series of 33 breast tumor samples from patients who relapsed (n = 14) or did not relapse (n = 19) under tamoxifen treatment from a different geographic location was subsequently used to explore the gene expression signature identified.

Results

Using a screening set of 18 tumor samples (from eight control patients and 10 TF patients), a 47-gene signature discriminating between TF and control samples was identified using cDNA arrays. In addition to ESR1/ERα, the top-ranked genes selected by statistical cross-analyses were MET, FOS, SNCG, IGFBP4, and BCL2, which were subsequently validated in a larger set of tumor samples (from 17 control patients and 18 TF patients). Confirmation at the protein level by tissue microarray immunohistochemistry was observed for ER-α, γ-synuclein, and insulin-like growth factor binding protein 4 proteins in the 35 original samples. In an independent series of breast tumor samples (19 nonrelapsing and 14 relapsing), reduced expression of ESR1/ERα, IGFBP4, SNCG, BCL2, and FOS was observed in the relapsing group and was associated with a shorter overall survival. Low mRNA expression levels of ESR1/ERα, BCL2, and FOS were also associated with a shorter relapse-free survival (RFS). Using a Cox multivariate regression analysis, we identified BCL2 and FOS as independent prognostic markers associated with RFS. Finally, the BCL2/FOS signature was demonstrated to have more accurate prognostic value for RFS than ESR1/ERα alone (likelihood ratio test).

Conclusions

We identified molecular markers including a BCL2/FOS signature associated with tamoxifen failure; these markers may have clinical potential in the management of ER-positive breast cancer.

Targeting AMPK: a new therapeutic opportunity in breast cancer

BACKGROUND

This paper reviews the mammalian Target Of Rapamycin (mTOR) pathway dysregulation in breast cancer, and the current evidence targeting this pathway directly or through activation of AMP-activated protein kinase (AMPK) as an additional therapeutic opportunity for intervention in breast cancer.

METHODS

Relevant articles were identified through computerised searches of Medline and Pubmed. Secondary articles were identified from the reference lists of key papers and by hand searching.

RESULTS AND CONCLUSION

The current consensus to target the AMPK/mTOR pathway in breast cancer is based on in vitro and epidemiological evidences. A low incidence of cancer in diabetic patients on metformin has been explained in vitro by the drug's anti-proliferative effect through activation of AMPK. There is a need to explore the anticancer effects of metformin and the potential to develop the therapeutic avenues offered by targeting the AMPK/mTOR pathway.

Delay from Symptom Onset Increases the Conversion Rate in Laparoscopic Cholecystectomy for Acute Cholecystitis

BACKGROUND

Randomized trials suggest that laparoscopic cholecystectomy should be performed on first admission for acute cholecystitis. However, this is not widely practiced, possibly because of a perceived high conversion rate. We hypothesized that delay from onset of symptoms may increase the conversion rate.

METHODS

We performed a retrospective case note review of patients undergoing emergency cholecystectomy in a single institution between January 2002 and December 2005. We analyzed whether delay from onset of symptoms was related to the conversion rate in patients with a histopathological diagnosis of acute cholecystitis.

RESULTS

Of patients who underwent emergency laparoscopic cholecystectomy in our institution, 32.4% (197/608) had acute cholecystitis on histopathology. The conversion rate of those with acute cholecystitis was considerably higher (24.4%) than for those with other pathologies (6.3%). For patients with acute cholecystitis, the conversion rates increased with duration of symptoms: 9.5%, 16.1%, 38.9%, and 38.6% for delays of 0-2 days, 3-4 days, 5-6 days, and > 6 days from symptom onset, respectively (chi-square for trend = 14.27, DF = 1, p = 0.00016). Most conversions were due to the presence of acute inflammatory adhesions.

CONCLUSIONS

Early intervention for acute cholecystitis (preferably within 2 days of onset of symptoms) is most likely to result in successful laparoscopic cholecystectomy; increasing delay is associated with conversion to open surgery.