Invasive lobular carcinoma of the breast; clinicopathologic profile and response to neoadjuvant chemotherapy over a 15-year period

INTRODUCTION

Invasive lobular carcinoma (ILC) accounts for 5-15% of invasive breast cancers. Typical ILC is oestrogen receptor (ER) positive and human epidermal growth factor receptor 2 (HER2) negative. Atypical biomarker profiles (ER- and HER2+, ER+ and HER2+ or triple negative) appear to differ from typical ILCs. This study compared subtypes of ILC in terms of clinical and pathological parameters, and response to neoadjuvant chemotherapy (NACT) according to biomarker profile.

METHODS

All patients with ILC treated in a single centre from January 2005 to December 2020 were identified from a prospectively maintained database. Clinicopathologic and outcome data was collected and analysed according to tumour biomarker profile.

RESULTS

A total of 582 patients with ILC were treated. Typical ILC was observed in 89.2% (n = 519) and atypical in 10.8% (n = 63). Atypical ILCs were of a higher grade (35% grade 3 vs 9.6% grade 3, p < 0.001). A larger proportion of atypical ILC received NACT (31.7% vs 6.9% p < 0.001). Atypical ILCs showed a greater response to NACT (mean RCB (Residual Cancer Burden Score) 2.46 vs mean RCB 3.41, p = 0.0365), and higher pathological complete response rates (15% vs 0% p = 0.017). Despite this, overall 5-year disease-free survival (DFS) was higher in patients with typical ILC (91% vs 83%, p = 0.001).

CONCLUSIONS

Atypical ILCs have distinct characteristics. They are more frequently of a higher grade and demonstrate a superior response to NACT. Despite the latter, atypical ILCs have a worse 5-year DFS which should be taken into consideration in terms of prognostication and may assist patient selection for NACT.

A multicentre review of the direct-access mammography programme in Ireland for women with breast pain

AIM

To assess the current use of the direct access mammography pathway for breast pain and the rate of breast cancer detection in this patient cohort.

MATERIALS AND METHODS

A retrospective review of general practitioner (GP)-referred mammograms performed during a 12-month period from January to December 2022 across four tertiary referral centres. With the use of medical records and GP referrals, patient demographics, presenting symptoms, family history, and clinical outcomes were recorded.

RESULTS

The present study comprised 2,046 patients of which 21.6% did not report breast pain at the time of referral. Thirty-five per cent had a positive family history with 40% of these patients having no breast pain. Twelve per cent were recalled with 30% of these patients requiring biopsy. An overall cancer detection rate (CDR) of 7 per 1000 was determined for women with mastalgia. A CDR of 0 per 1,000 was determined for women <50 years with mastalgia alone and no additional risk factors for malignancy. Fisher's exact test showed no statistically significant association between breast pain and breast cancer.

CONCLUSION

There was no statistically significant relationship found between breast pain and breast cancer. This review suggests a low cancer detection rate in women <50 years. In women <50 years with mastalgia without additional symptoms or family history, breast imaging is not required.

210 AUDIT OF AN AUDIT: UNDERSTANDING THE INTERPRETATION AND REPORTING OF KEY PERFORMANCE VARIABLES OF THE IRISH NATIONAL AUDIT OF STROKE

Background

The Irish National Audit of Stroke (INAS) coordinates the collection and analysis of key performance variables which can be interpreted as proxies of care quality in stroke. Time metrics such as “Time-to-CT” and “Time-to-Thrombolysis” reflect the organisation of in-hospital stroke care pathways, with shorter times reflecting better care coordination and quality. While the INAS data dictionary defines each variable, differing interpretations of a definition can impact on the exact data point collected. We wished to understand the interpretation and reporting of key performance variables at all clinical sites reporting to INAS.

Methods

An online survey in three parts was designed and distributed to 34 INAS audit co-ordinators along with the INAS dictionary definition of each data variable. Audit co-ordinators were asked to select the exact data point they collect for that variable from a dropdown list, with space also allotted for free-text entry of any challenges they may encounter for that variable.

Results

Responses were received from 11/34 audit co-ordinators, representing 10/24 hospitals. Variability was seen in the specific times selected for data points including hospital arrival time, team time, and brain imaging time. This variability was seen across sites and regions. Data points with less scope for interpretation such as thrombolysis or thrombolysis time showed less variability.

Conclusion

By understanding the scope of responses given to any data point definition and the challenges that may exist for audit co-ordinators, it is hoped to achieve a consensus approach to defining variables for a robust core data set. Future data definitions may be refined to assist in the collection of exact data points that are accurate, consistent and reproducible across hospital sites. In so doing, all key elements of a patient’s pathway can be captured accurately and compared with best practice guidelines with a view to optimising future care provision and service organisation.

O79: THE ROLE OF SENTINEL LYMPH NODE BIOPSY IN BREAST CANCER PATIENTS OVER THE AGE OF 80 – HOW MUCH IS ENOUGH?

Introduction

Recent studies have suggested that sentinel lymph node biopsy (SLNB) can be omitted in newly diagnosed elderly breast cancer (BC) patients as it may not influence decisions regarding further therapeutic intervention. The aim of this study was to assess the impact of SLNB on further surgical intervention as well as adjuvant treatments in patients over the age of 80.

Method

A retrospective study was performed involving all BC patients over the age of 80 diagnosed between 2008 and 2017 who underwent SLNB as part of their initial surgery. Patient/tumour characteristics and adjuvant treatments were recorded.

Result

127 patients underwent SLNB in the study period. The median age was 82 (Range: 80-95). 91/127 (71.6%) had ductal pathology, median tumour grade was 2, and oestrogen receptor positivity was seen in 89% of patients. The median number of sentinel nodes removed was 2 (Range: 1-6). 45 patients (35.4%) had a positive sentinel node (median positive nodes = 1). Of the 45 patients, 11 proceeded to axillary lymph node dissection (ALND) (11/127; 8.6%). The median number of nodes excised during ALND was 14 (Range:7-25) and 6 patients (6/11) had further positive nodes. 9% of patients with a positive node received adjuvant chemotherapy, 87% received adjuvant radiotherapy and 79% received hormonal therapy.

Conclusion

Although SLNB positivity is still used in the elderly patients, only a few patients (&lt;10%) proceed to ALND or receive adjuvant chemotherapy. Hence performing a SLNB should be carefully considered when treating patients over the age of 80

Take-home message

The use of SLNB in elderly patients needs to be considered in node negative patients

Value of a 21-gene expression assay on core biopsy to predict neoadjuvant chemotherapy response in breast cancer: systematic review and meta-analysis

BACKGROUND

A recurrence score based on a 21-gene expression assay predicts the benefit of adjuvant chemotherapy in oestrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-negative breast cancer. This systematic review aimed to determine whether the 21-gene expression assay performed on core biopsy at diagnosis predicted pathological complete response (pCR) to neoadjuvant chemotherapy.

METHODS

The study was performed according to PRISMA guidelines. Relevant databases were searched to identify studies assessing the value of the 21-gene expression assay recurrence score in predicting response to neoadjuvant chemotherapy in patients with breast cancer. The Newcastle-Ottawa Scale was used to assess the quality of the studies. Results are reported as risk ratio (RR) with 95 per cent confidence interval using the Cochrane-Mantel-Haenszel method for meta-analysis. Sensitivity analyses were carried out where appropriate.

RESULTS

Seven studies involving 1744 patients reported the correlation between pretreatment recurrence score and pCR. Of these, 777 patients (44.6 per cent) had a high recurrence score and 967 (55.4 per cent) a low-intermediate score. A pCR was achieved in 94 patients (5.4 per cent). The pCR rate was significantly higher in the group with a high recurrence score than in the group with a low-intermediate score (10.9 versus 1.1 per cent; RR 4.47, 95 per cent c.i. 2.76 to 7.21; P < 0.001). A significant risk difference was observed between the two groups (risk difference 0.10, 0.04 to 0.15; P = 0.001).

CONCLUSION

A high recurrence score is associated with higher pCR rates and a low-intermediate recurrence score may indicate chemoresistance. Routine assessment of recurrence score by the 21-gene expression assay on core biopsy might be of value when considering neoadjuvant chemotherapy in patients with ER-positive, HER2-negative breast cancer.

Abstract P5-04-12: Withdrawn

This abstract was withdrawn by the authors.

Citation Format: Charmsaz S, Doherty B, Cocchiglia S, Bolger J, Vareslija D, McCartan D, Hill A, Young L. Withdrawn [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-04-12.

Abstract PD6-06: Oncologic outcome of pregnancy associated breast cancer: A case-control study

Introduction and Aims

Pregnancy-associated breast cancer (PABC) is defined as the diagnosis of invasive breast cancer during the gestational period, within one year of pregnancy or any time during lactation. A diagnosis of PABC has traditionally been attributed a poor prognosis. The aim of this study was to assess the long-term outcome of patients diagnosed with PABC compared to a cohort of age-matched control patients.

Methods

A single-institution retrospective chart review was performed in 188 patients with PABC treated between the years of 1992 and 2015.Non-PABC controls were selected to match based on age and year of diagnosis. Clinicopathologic features, surgical and adjuvant treatments received, and clinical outcomes were assessed. Patients who were stage IV at diagnosis were excluded. Overall survival was estimated using Kaplan-Meier methods and compared between cases and controls using a log-rank test stratified on matched pair.

Results

Out of 188 patients with PABC, 63 (34%) were pregnant at the time of diagnosis and 125 diagnosed within 1 year of pregnancy (average: 6 months post partum). The characteristics of the PABC and case-matched controls are listed in Table 1 . Important pathological differences were evident with PABC patients compared to the non-PABC controls. PABC cases were more likely to be high grade (p&lt;.001), node positive (p=.039) and less likely to be estrogen or progesterone receptor positive (p=.003). The majority of both cases and controls received chemotherapy (18% neoadjuvant). In the patients who were pregnant at time of diagnosis, 19 received chemotherapy during their pregnancy, with the most common combination being AC followed by paclitaxel in the post-partum period. Five year overall survival was similar for both groups, 88% for PABC patients and 95% for non-PABC case controls (p=.746) with a median follow up of 5.1 years.

Table 1: Demographics, treatment, and outcome of PABC and non-PABC case-matched controlsPABC n=188Non PABC n=188p-valueDemographicsAge (mean)35.7yrs35.9yrs0.633BRCA1/2 carrier22%12%0.072SurgeryBreast Conservation22%38%0.001Immediate reconstruction post mastectomy81%84%0.544PathologyGrade 388%70%&lt;0.001ER and/or PR positive56%72%0.003HER2 positive27%22%0.283Triple negative27%20%0.145Node positive27%47%0.039Clinical StageI-II67%79%0.010III33%21%Adjuvant treatmentsChemotherapy99%21%&lt;0.001Neoadjuvant18%17%0.849Anthracycline84%81%0.393Taxane82%75%0.148Anti-HER220%15%0.238Anti-estrogen53%68%0.003Radiotherapy57%62%0.4005-year OS88%95%0.746Figures are reported as percentages for categorical variables. OS: Overall survival

Conclusion

Diagnostic and therapeutic advances have improved the oncological outcome for breast cancer patients, but not all of these have been adapted for pregnant patients. The consistent finding of higher-stage tumors in these patients reinforces the importance of utilizing developments in systemic treatments, potentially through case registries, to evaluate outcomes. PABC is associated with more adverse features than non-PABC controls matched for age and year of diagnosis. However, PABC is not in itself an adverse prognostic factor for survival after correcting for pathologic features.

Citation Format: McCartan D, Kamer S, Eaton A, Seidman A, Murphy C, Gemignani M, Goldfarb S. Oncologic outcome of pregnancy associated breast cancer: A case-control study [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr PD6-06.

A MultiCenter Pilot Randomized Controlled Trial of Remote Ischemic Preconditioning in Major Vascular Surgery

A pilot randomized controlled trial that evaluated the effect of remote ischemic preconditioning (RIPC) on clinical outcomes following major vascular surgery was performed. Eligible patients were those scheduled to undergo open abdominal aortic aneurysm repair, endovascular aortic aneurysm repair, carotid endarterectomy, and lower limb revascularization procedures. Patients were randomized to RIPC or to control groups. The primary outcome was a composite clinical end point comprising any of cardiovascular death, myocardial infarction, new-onset arrhythmia, cardiac arrest, congestive cardiac failure, cerebrovascular accident, renal failure requiring renal replacement therapy, mesenteric ischemia, and urgent cardiac revascularization. Secondary outcomes were components of the primary outcome and myocardial injury as assessed by serum troponin values. The primary outcome occurred in 19 (19.2%) of 99 controls and 14 (14.1%) of 99 RIPC group patients ( P = .446). There were no significant differences in secondary outcomes. Our trial generated data that will guide future trials. Further trials are urgently needed.

Abstract PD3-5: Survival benefit conferred by the androgen receptor is lost in aromatase inhibitor treated breast cancer

Aromatase Inhibitors have proven to be most effective in the treatment of post-menopausal breast cancer. Their mode of action is to inhibit the synthesis of estrogen (estrone) by the aromatase enzyme Cyp 19 thereby blocking ligand-dependent activation of the estrogen receptor. What has not been addressed to date is how cells that are deprived of estrogen, may potentially, adapt to the more androgenic environment resulting from long-term treatment with AI therapy. Research from our lab has identified the homeobox protein, HOXC11, to be an indicator of poor response to endocrine therapy and development of metastasis. To further our understanding of HOXC11 and its role in the development of endocrine-resistance and metastatic spread we undertook an RNA-seq experiment to identify its target genes in resistant breast cancer. This analysis identified PSAP, IFIT1 and HSP90AA1. Both PSAP (an androgen agonist) and HSP90AA1 (AR chaperone) are closely associated with AR which led to further investigation into the role of HOXC11 in the development of steroidal adaptability in Letrozole-resistant breast cancer. We hypothesize that HOXC11 regulated expression of PSAP results in oncogenic activation of AR in an AI resistant setting. Our findings have shown that AI-resistant cell lines in vitro have significantly elevated levels of AR and that loss of HOXC11 results in concommitant decrease in AR mRNA. In AI resistance expression of HOXC11 results in upregulation/stabilization of AR by PSAP thus enabling the tumour to adapt to use androgenic steroids for cell proliferation. The anti-androgen, Bicalutamide, reduces cell proliferation and cell motility in AI resistant cell lines. Survival analysis of AR in a TMA (n = 488) indicates that AR confers a survival benefit in the tamoxifen treated population. This protective effect is diminished in patients receiving AI therapy and is reflected in the altered Hazard Ratio of AR from the total population (HR: 0.485) to the AI treated cohort (HR: 1.197). Secreted PSAP was readily detectable in breast cancer patient serum and associates significantly with expression of HOXC11 in matched patient tissue (∼20). PSAP is associated with poor response to endocrine therapy and metastatic spread of prostate cancer and as it is secreted it could potentially be used to monitor patients on AI who might benefit from dual targeted therapy treatment.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr PD3-5.

P4-01-10: The Role of the Steroid Receptor Coactivator SRC1 and Its Functional Partner HOXC11 in the Development of Endocrine Resistant Breast Cancer

Background: The steroid receptor coactivator; SRC1, has been well described in the development of endocrine resistant breast cancer. SRC1 associates with clinically aggressive tumours and promotion of distant metastasis. It directly interacts with the developmental transcription factor, HOXC11 and together they are found to strongly predict poor disease-free survival in breast cancer patients (hazard ratios: 5.79; P &lt; 0.0001). In this study, we investigate the mechanism of SRC1 and HOXC11 action in tumour adaptability and subsequent resistance to endocrine therapy.

Materials and Methods: Cells which are resistant to tamoxifen (LY2s) have enhanced SRC1 and HOXC11 mRNA and protein expression in comparison to their endocrine sensitive parent cells (MCF-7s). ChIP-sequencing data for SRC1- and HOXC11- DNA interactions in conjunction with DNA microarray and RNA-sequencing data identified potential signalling targets at play in the LY2 model of endocrine resistance. Real-time analysis and flow cytometry confirmed these interactions at a transcriptional and protein level. These observations were further confirmed in primary breast cancer cultures using flow cytometry.

Results: SRC1 and HOXC11 interactions are driven in tamoxifen treated LY2 resistant cells. Combined SRC1 ChIP-sequencing and expression array data analysed in conjunction with HOXC11 ChIP-sequencing and RNA-sequencing data reveal that the SRC1/HOXC11 transcriptional process can orchestrate the loss of luminal cell markers such as ERα, CD24 and PTCH1 whilst concomitantly upregulating mediators of tumourigenicity such as CD44 and MSI2. Primary breast cancer cultures confirm the loss of CD24 in tamoxifen resistant patients. In these patients, loss of CD24 was accompanied by loss of steroid receptor expression (ERα and PR) and by a gain of the basal marker CD44.

Discussion: Here, we describe a new signalling pathway where SRC1 and HOXC11 regulate two distinct but complementary mechanisms to drive tumour adaptability. Silencing of luminal cell markers and a concomitant increase in a basal cell phenotype has the potential to alter the survival mechanism of breast cancer cells to evade targeted therapy.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-01-10.

Novel non-steroidal p160 coactivator interactions in tamoxifen resistant breast cancer

Abstract #3038

While most breast cancer patients initially respond to endocrine therapy, 30-40% of cases relapse within 5 years of treatment. Translational studies from our group and others have provided substantial evidence of a significant role for p160 family of Steroid Receptor Co-activator (SRC) proteins in the development of resistance to endocrine therapy. In this study we have investigated novel non-steroidal SRC-1 interactions in endocrine resistant breast cancer.&#x2028; A mass-spectrometry-based screen was used to identify proteins which differentially interact with SRC-1 in endocrine resistant compared with endocrine sensitive breast cancer cells. The developmental protein, HOXC11, was confirmed as an SRC-1 interacting partner. HOXC11 was shown to be over-expressed in tamoxifen-resistant cells using immunocytochemistry and was observed to translocate to the nucleus and peri-nuclear region when cells were treated with tamoxifen. In a breast cancer TMA (n=560) HOXC11 was found to correlate with disease recurrence and metastasis (local and distant). Moreover, in addition to associating with SRC-1, HOXC11 was found to be a strong predictor of reduced disease-free survival on endocrine treatment (Hazard ratio: 5.79; p&lt;0.0001).&#x2028; Bioinformatic analysis identified S100β as a target gene of the HOXC11 transcription factor. Interestingly, the s100 family of calcium binding proteins has been associated with poor outcome and reduced disease-free survival in melanoma. Reporter assays were used to confirm HOXC11 as a mediator of S100β transcription. Regulation of the target gene in the presence of tamoxifen was shown to be modified by activation of protein kinase A (PKA) which has previously been implicated in the enhancement of tamoxifenÂs agonist profile. Here we have defined HOXC11 as a non-steroidal interacting partner of SRC-1; furthermore, this interaction appears to be regulated by the activation of PKA. HOXC11 expression in our breast cancer patient cohort associated with poor survival and the development of metastatic disease. This study provides evidence of a novel mechanism at play in endocrine resistant breast cancer cells.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 3038.

The differential effects of chlorpromazine and haloperidol on latent inhibition in healthy volunteers

Latent inhibition (LI) is a measure of reduced learning about a stimulus to which there has been prior exposure without any consequence. It therefore requires a comparison between a pre-exposed (PE) and a non-pre-exposed (NPE) condition. Since, in animals, LI is disrupted by amphetamines and enhanced by antipsychotics, LI disruption has been proposed as a measure of the characteristic attentional deficit in schizophrenia: the inability to ignore irrelevant stimuli. The findings in humans are, however, inconsistent. In particular, a recent investigation suggested that since haloperidol disrupted LI in healthy volunteers, and LI was normal in non-medicated patients with schizophrenia, the previous findings in schizophrenic patients were entirely due to the negative effects of their medication on LI (Williams et al., 1998). We conducted two studies of antipsychotic drug effects on auditory LI using a within-subject, parallel group design in healthy volunteers. In the first of these, single doses of haloperidol (1 mg. i.v.) were compared with paroxetine (20 mg p.o.) and placebo, and in the second, chlorpromazine (100 mg p.o.) was compared with lorazepam (2 mg. p.o.) and placebo. Eye movements, neuropsychological test performance (spatial working memory (SWM), Tower of London and intra/extra dimensional shift, from the CANTAB test battery) and visual analogue rating scales, were also included as other measures of attention and frontal lobe function. Haloperidol was associated with a non-significant reduction in LI scores, and dysphoria/akathisia (Barnes Akathisia Rating Scale) in three-quarters of the subjects. The LI finding may be explained by increased distractibility which was indicated by an increase in antisaccade directional errors in this group. In contrast, LI was significantly increased by chlorpromazine but not by an equally sedative dose of lorazepam (both drugs causing marked decreases in peak saccadic velocity). Paroxetine had no effect on LI, eye movements or CANTAB neuropsychological test performance. Haloperidol was associated with impaired SWM, which correlated with the degree of dysphoria/akathisia, but no other drug effects on CANTAB measures were detected. We conclude that the effect of antipsychotics on LI is both modality and pharmacologically dependent and that further research using a wider range of antipsychotic compounds is necessary to clarify the cognitive effects of these drugs, and to determine whether there are important differences between them.