The role of infiltrating lymphocytes in the neo-adjuvant treatment of women with HER2-positive breast cancer

Background

Pre-treatment tumour-associated lymphocytes (TILs) and stromal lymphocytes (SLs) are independent predictive markers of future pathological complete response (pCR) in HER2-positive breast cancer. Whilst studies have correlated baseline lymphocyte levels with subsequent pCR, few have studied the impact of neoadjuvant therapy on the immune environment.

Methods

We performed TIL analysis and T-cell analysis by IHC on the pretreatment and ‘On-treatment’ samples from patients recruited on the Phase-II TCHL (NCT01485926) clinical trial. Data were analysed using the Wilcoxon signed-rank test and the Spearman rank correlation.

Results

In our sample cohort (n = 66), patients who achieved a pCR at surgery, post-chemotherapy, had significantly higher counts of TILs (p = 0.05) but not SLs (p = 0.08) in their pre-treatment tumour samples. Patients who achieved a subsequent pCR after completing neo-adjuvant chemotherapy had significantly higher SLs (p = 9.09 × 10^–3) but not TILs (p = 0.1) in their ‘On-treatment’ tumour biopsies. In a small cohort of samples (n = 16), infiltrating lymphocyte counts increased after 1 cycle of neo-adjuvant chemotherapy only in those tumours of patients who did not achieve a subsequent pCR. Finally, reduced CD3 + (p = 0.04, rho = 0.60) and CD4 + (p = 0.01, rho = 0.72) T-cell counts in 'On-treatment' biopsies were associated with decreased residual tumour content post-1 cycle of treatment; the latter being significantly associated with increased likelihood of subsequent pCR (p < 0.01).

Conclusions

The immune system may be ‘primed’ prior to neoadjuvant treatment in those patients who subsequently achieve a pCR. In those patients who achieve a pCR, their immune response may return to baseline after only 1 cycle of treatment. However, in those who did not achieve a pCR, neo-adjuvant treatment may stimulate lymphocyte influx into the tumour.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10549-021-06244-1.

An exploration of the impact of ethanol diluent on breath alcohol concentration in patients receiving paclitaxel chemotherapy

PURPOSE

This study aimed to provide a better understanding of the impact of paclitaxel chemotherapy on breath alcohol in an Irish population.

METHODS

Patients attending the Oncology Day Unit at Beaumont Hospital were invited to participate on the day of their treatment. The brand of paclitaxel used was Actavis Pharma Inc and contained 6 mg/mL paclitaxel in 50% Ethanol/ 50% Cremophor EL. Breath alcohol concentration was measured using the AlcoSense ™ Breathalyser on three separate visits. The primary end-point was the number of patients who were above the legal threshold for drink driving in Ireland.

RESULTS

In total, 50 patients were recruited. 36 (68%) were female. The most common diagnosis was breast cancer (56%). Ten (20%) patients had metastatic disease and 4 (8%) had liver metastases. The mean paclitaxel dose administered was 118 mg. The mean amount of ethanol infused was 7.7 g. 27 patients had a detectable breath alcohol level on at least one visit. The mean breath alcohol concentration was 2 mcg/100 mL or 0.02 mg/L of breath. The maximum concentration of ethanol in exhaled breath was 11 mcg/100 mL or 0.11 mg/L which is 50% of the statutory limit for drink driving in Ireland. A weak correlation was observed between ethanol concentration in exhaled breath and the total amount of ethanol administered. Although no patient exceeded the general limit for drink driving in Ireland, three (6%) participants had a breath alcohol concentration above the threshold for professional, learner or novice drivers.

CONCLUSION

Although definitive conclusions are limited by relatively small numbers, it seems unlikely that weekly paclitaxel infusions pose any significant risk to patients driving.

Abstract OT3-06-01: Phase Ib clinical trial of coPANlisib in combination with Trastuzumab emtansine (T-DM1) in pre-treated unresectable locally advanced or metastatic HER2-positive breAst cancer (BC) “PANTHERA”-CTRIAL-IE 17-13

Background:The phosphoinositide 3 kinase (PI3K) pathway is important in the oncogenic function of HER2. Aberrant activation of PI3K is implicated in resistance to trastuzumab and other HER2-targeted therapies and is frequent, with up to 22% of HER2 positive breast cancer having a PIK3CA mutation. Copanlisib is a pan-class 1 PI3K inhibitor administered i.v. with low nanomolar activity against both PI3Kα and PI3Kβ. Copanlisib has been shown to re-sensitise trastuzumab resistant cell lines to trastuzumab with synergism seen in some cell lines between copanlisib and HER2 targeted therapy.

Trial design: This is a phase Ib open label, single arm adaptive, multi-centre trial of copanlisib in combination with T-DM1. Eligible patients will receive T-DM1 at 3.6mg/kg i.v. on day 1 of a 21-day cycle plus copanlisib. Copanlisib will be administered i.v. according to the dose escalation scheme (dose level 1 is 45mg on days 1 and 8, dose level 2 is 60mg on days 1 and 8, dose level 3 is 60mg on days 1, 8, and 15). Dose level -1 will be 45 mg on day 1 in case dose de-escalation is needed. We will enrol 3 to 6 patients per dose level. All patients in each level must have completed at least the first cycle of therapy before enrolment in the next dose level. Patients not completing the first cycle for a reason other than toxicity will be replaced. Dose escalation and determination of the Maximum Tolerated Dose (MTD) will be based on the occurrence of Dose Limiting Toxicities (DLT).

Eligibility criteria:Eligible patients are those with unresectable locally advanced or metastatic HER2-positive BC who previously received trastuzumab and a taxane, separately or in combination. Participants must have adequate organ function and ECOG PS ≤ 2

Objectives:The primary objective is to determine the MTD for copanlisib in combination with T-DM1 in patients with pre-treated unresectable locally advanced or metastatic HER2-positive BC. Secondary objectives include evaluating the safety, efficacy and cardiotoxicity in patients treated with this regimen. Exploratory objectives include examining for predictive biomarkers in tumour tissue and blood or plasma and to examine molecular tumour adaptation to clinical trial therapy.

Statistical methods: Patients will be accrued in cohorts of 3 patients according to a standard 3+3 algorithm, with dose escalation and determination of MTD based on the occurrence of DLT, using the usual threshold probability of 33%. The final dose level will be expanded to include a total of 6 additional patients (expansion cohort).

Present accrual and target accrual:The trial will start accrual in October 2018. Maximum of 24 patients will be enrolled.

Citation Format: Hassan A, Gullo G, O'Reilly S, Ruiz-Borrego M, Toomey S, Grogan L, Breathnach O, Morris PG, Walshe JM, Crown J, O'Mahony D, Falcon A, Egan K, Hernando A, Teiserskiene A, Kelly CM, Coate L, Hennessy BT. Phase Ib clinical trial of coPANlisib in combination with Trastuzumab emtansine (T-DM1) in pre-treated unresectable locally advanced or metastatic HER2-positive breAst cancer (BC) “PANTHERA”-CTRIAL-IE 17-13 [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 OT3-06-01.

Abstract OT3-06-05: A phase Ib/II trial of coPANlisib in combination with tratuzumab in pretreated recurrent or metastatic HER2-positive breast cancer “PantHER”

Background

The phosphoinositide 3 kinase (PI3K) pathway is important in the oncogenic function of HER2. Aberrent activation of PI3K is implicated in resistance to trastuzumab and other HER2-targeted therapies and is frequent, with up to 22% of HER2 positive breast cancer having a PIK3CA mutation. Copanlisib is a pan-class 1 PI3K inhibitor that shows particular activity against PI3Kα, the isoform encoded by the PIK3CA gene. Copanlisib has been shown to re-sensitise trastuzumab resistant cell lines to trastuzumab with synergism seen in some cell lines between copanlisib and HER2 targeted therapy.

Trial design

The study is a phase Ib/II open label, single arm adaptive, multi-centre trial of copanlisib in combination with trastuzumab. Eligible patients are treated with a dose escalation schedule of copanlisib IV on Days 1, 8 and 15 of a 28 day cycle with trastuzumab 2 mg/kg weekly (loading dose of 4 mg/kg in cycle 1). The phase II dose will be based on the maximum tolerated dose (MTD) established in Phase Ib. Patients are treated until radiologic or symptomatic progression, unacceptable toxicity, consent withdrawal or physician's decision.

Eligibility criteria

Eligible patients must have recurrent incurable or metastatic HER2-positive breast cancer that has progressed on at least one prior line of trastuzumab or T-DM1-based treatment regimen in this setting. Patients with treated and controlled brain metastases are eligible. Participants must have adequate organ function and ECOG PS ≤ 2. Patients recruited for the Phase II part of the study must have a PIK3CA mutation. Patients with uncontrolled arterial hypertension, uncontrolled diabetes or recent clinically serious infections are excluded.

Specific aims

The primary end point for the phase Ib part of this study is to determine the MTD for the combination. For the phase II study is anti-tumour efficacy, measured by Clinical Benefit Rate (CBR).

Secondary end points are evaluation of safety and tolerability, progression-free survival, time to treatment failure, duration of response and overall survival. Incorporated translational endpoints include examination of molecular tumor adaptation in tissue and blood. Given the role of PI3K in cellular glucose metabolism, an additional exploratory objective is to determine if quantitive reduction in metabolic signal on Positron Emission Tomography-Computed Tomography (PET-CT) is predictive of benefit from therapy.

Statistical methods

To establish the MTD, we use a modified 3+3 design where 3 additional patients will be accrued even if the first 3 patients accrued experience no dose limiting toxicities (DLT) in sequential cohorts for a planned 12 patients. To determine the CBR, a one sample exact binomial test with a one sided significance level of 5%, 19 evaluable patients will provide &gt;80% power to detect a difference between the null hypothesis proportion of 30% for CBR versus the alternative hypothesis proportion of 65%.

Present accrual and target accrual

There are 9 patients recruited so far to the phase Ib part of this study. Target accrual is 12 and for phase II is 19 patients.

Contact information for people with a specific interest in the trial

Prof Bryan Hennessy, Beaumont Hospital, Dublin Ireland

Funded by Bayer

Citation Format: Keegan NM, Walshe J, Gullo G, Kennedy J, Bulger K, Kelly CM, Crown J, Toomey S, Egan K, Kerr J, Given M, Hernando A, Teiserskiene A, Grogan L, Breathnach O, Morris PG, Keane M, Hennessy BT. A phase Ib/II trial of coPANlisib in combination with tratuzumab in pretreated recurrent or metastatic HER2-positive breast cancer “PantHER” [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr OT3-06-05.

BCL2 protein signalling determines acute responses to neoadjuvant chemoradiotherapy in rectal cancer

In locally advanced rectal cancer, neoadjuvant chemoradiotherapy is performed prior to surgery to downstage the tumour. Thirty to 40 % of patients do not respond. Defects in apoptotic machinery lead to therapy resistance; however, to date, no study quantitatively assessed whether B cell lymphoma 2 (BCL2)-dependent regulation of mitochondrial apoptosis, effector caspase activation downstream of mitochondria or a combination of both predicts patient responses. In a cohort of 20 rectal cancer patients, we performed protein profiling of tumour tissue and employed validated ordinary differential equation-based systems models of apoptosis signalling to calculate the ability of cancer cells to undergo apoptosis. Model outputs were compared to clinical responses. Systems modelling of BCL2-signalling predicted patients in the poor response group (p = 0.0049). Systems modelling also demonstrated that rectal cancers depended on BCL2 rather than B cell lymphoma-extra large (BCL(X)L) or myeloid cell leukemia 1 (MCL1) for survival, suggesting that poor responders may benefit from therapy with selective BCL2 antagonists. Dynamic modelling of effector caspase activation could not stratify patients with poor response and did not further improve predictive power. We deliver a powerful patient stratification tool identifying patients who will likely not benefit from neoadjuvant chemoradiotherapy and should be prioritised for surgical resection or treatment with BCL2 antagonists.

KEY MESSAGES

Modelling BCL2-family proteins identifies patients unresponsive to therapy. Caspase activation downstream of mitochondria cannot identify these patients. Rectal tumours of poor responders are BCL2- but not BCL-XL-dependent. DR_MOMP allows clinicians to identify patients who would not benefit from therapy. DR_MOMP is also a useful patient stratification tool for BCL2 antagonists.

The prognostic value of tumour regression grade following neoadjuvant chemoradiation therapy for rectal cancer

AIM

To date, there is no uniform consensus on whether tumour regression grade (TRG) is predictive of outcome in rectal cancer. Furthermore, the lack of standardization of TRG grading is a major source of variability in published studies. The aim of this study was to evaluate the prognostic impact of TRG in a cohort of patients with locally advanced rectal cancer treated with neoadjuvant chemoradiation therapy (CRT). In addition to the Mandard TRG, we utilized four TRG systems modified from the Mandard TRG system and applied them to the cohort to assess which TRG system is most informative.

METHOD

One-hundred and fifty-three patients with a T3/T4 and/or a node-positive rectal cancer underwent neoadjuvant 5-fluorouracil-based CRT followed by surgical resection.

RESULTS

Thirty-six (23.5%) patients achieving complete pathological response (ypCR) had a 5-year disease-free survival (DFS) rate of 100% compared with a DFS rate of 74% for 117 (76.5%) patients without ypCR (P = 0.003). The Royal College of Pathologists (RCPath) TRG best condenses the Mandard five-point TRG by stratifying patients into three groups with distinct 5-year DFS rates of 100%, 86% and 67%, respectively (P = 0.001). In multivariate analysis, pathological nodal status and circumferential resection margin (CRM) status, but not TRG, remained significant predictors of DFS (P = 0.002, P = 0.035 and P = 0.310, respectively).

CONCLUSION

Our findings support the notion that ypCR status, nodal status after neoadjuvant CRT and CRM status, but not TRG, are predictors of long-term survival in patients with locally advanced rectal cancer.

Molecular subclasses of breast cancer: how do we define them? The IMPAKT 2012 Working Group Statement

The 2012 IMPAKT task force investigated the medical usefulness of current methods for the classification of breast cancer into the 'intrinsic' molecular subtypes (luminal A, luminal B, basal-like and HER2). A panel of breast cancer and/or gene expression profiling experts evaluated the analytical validity, clinical validity and clinical utility of two approaches for molecular subtyping of breast cancer: the prediction analysis of microarray (PAM)50 assay and an immuno-histochemical (IHC) surrogate panel including oestrogen receptor (ER), HER2 and Ki67. The panel found the currently available evidence on the analytical validity and clinical utility of Ki67 based on a 14% cut-off and PAM50 to be inadequate. The majority of the working group members found the available evidence on the analytical validity, clinical validity and clinical utility of ER/HER2 to be convincing. The panel concluded that breast cancer classification into molecular subtypes based on the IHC assessment of ER, HER2 and Ki67 with a 14% cut-off and on the PAM50 test does not provide sufficiently robust information to modify systemic treatment decisions, and recommended the use IHC for ER and HER2 for the identification of clinically relevant subtypes of breast cancers. Methods for breast cancer classification into molecular subtypes should, however, be incorporated into clinical trial design.

Overcoming resistance and restoring sensitivity to HER2-targeted therapies in breast cancer

BACKGROUND

Approximately 15%-23% of breast cancers overexpress human epidermal growth factor receptor 2 (HER2), which leads to the activation of signaling pathways that stimulate cell proliferation and survival. HER2-targeted therapy has substantially improved outcomes in patients with HER2-positive breast cancer. However, both de novo and acquired resistance are observed.

DESIGN

A literature search was performed to identify proposed mechanisms of resistance to HER2-targeted therapy and identified novel targets in clinical development for treating HER2-resistant disease.

RESULTS

Proposed HER2-resistance mechanisms include impediments to HER2-inhibitor binding, signaling through alternative pathways, upregulation of signaling pathways downstream of HER2, and failure to elicit an appropriate immune response. Although continuing HER2 inhibition beyond progression may provide an additional clinical benefit, the availability of novel therapies targeting different mechanisms of action could improve outcomes. The developmental strategy with the most available data is targeting the phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin (mTOR) pathway. The oral mTOR inhibitor everolimus has shown promising activity in combination with chemotherapy and trastuzumab in trastuzumab-refractory, advanced breast cancer.

CONCLUSIONS

Non-HER2-targeted therapy is a promising means of overcoming resistance to HER2-targeted treatment. Ongoing clinical studies will provide additional information on the efficacy and safety of novel targeted therapies in HER2-resistant advanced breast cancer.

Modeling ductal carcinoma in situ: a HER2-Notch3 collaboration enables luminal filling

A large fraction of ductal carcinoma in situ (DCIS), a non-invasive precursor lesion of invasive breast cancer, overexpresses the HER2/neu oncogene. The ducts of DCIS are abnormally filled with cells that evade apoptosis, but the underlying mechanisms remain incompletely understood. We overexpressed HER2 in mammary epithelial cells and observed growth factor-independent proliferation. When grown in extracellular matrix as three-dimensional spheroids, control cells developed a hollow lumen, but HER2-overexpressing cells populated the lumen by evading apoptosis. We demonstrate that HER2 overexpression in this cellular model of DCIS drives transcriptional upregulation of multiple components of the Notch survival pathway. Importantly, luminal filling required upregulation of a signaling pathway comprising Notch3, its cleaved intracellular domain and the transcriptional regulator HES1, resulting in elevated levels of c-MYC and cyclin D1. In line with HER2-Notch3 collaboration, drugs intercepting either arm reverted the DCIS-like phenotype. In addition, we report upregulation of Notch3 in hyperplastic lesions of HER2 transgenic animals, as well as an association between HER2 levels and expression levels of components of the Notch pathway in tumor specimens of breast cancer patients. Therefore, it is conceivable that the integration of the Notch and HER2 signaling pathways contributes to the pathophysiology of DCIS.

Quantitative proteomic analysis in breast cancer

Much progress has recently been made in the genomic and transcriptional characterization of tumors. However, historically the characterization of cells at the protein level has suffered limitations in reproducibility, scalability and robustness. Recent technological advances have made it possible to accurately and reproducibly portray the global levels and active states of cellular proteins. Protein microarrays examine the native post-translational conformations of proteins including activated phosphorylated states, in a comprehensive high-throughput mode, and can map activated pathways and networks of proteins inside the cells. The reverse-phase protein microarray (RPPA) offers a unique opportunity to study signal transduction networks in small biological samples such as human biopsy material and can provide critical information for therapeutic decision-making and the monitoring of patients for targeted molecular medicine. By providing the key missing link to the story generated from genomic and gene expression characterization efforts, functional proteomics offer the promise of a comprehensive understanding of cancer. Several initial successes in breast cancer are showing that such information is clinically relevant.

Abstract P3-10-23: Caveolin 1 and Patient Outcomes in Breast Cancer

Introduction: Caveolin 1 (Cav1) protein is a structural component of caveolae in cell membranes and is also present in the cell cytoplasm, nucleus and extracellular milieu. It regulates multiple cellular processes and has been reported to both positively and negatively effect tumour progression. In normal and malignant breast tissue Cav1 is immunohistochemically expressed in myoepithelial and stromal cells but rarely in luminal epithelial or breast cancer cells. Recent reports have correlated Cav1 expression in the stromal tumour microenvironment with lower tumor stage, grade and improved prognosis. This suggests a separate role for Cav 1 in influencing tumour behaviour by regulating the tumour microenvironment. Our aim was to further investigate the role of Cav1 in breast cancer by for the first time analysing its expression by reverse phase protein array(RPPA). Methods: We examined expression levels of Cav1 in 52 breast cancer cell lines and a large human early breast cancer cohort(n=712) with cancer cells composing 70% of the macrodissected breast cancer specimens used. Data was recorded when available for each case on standard clinical, pathological and survival endpoints. We examined the effect of Cav1 expression on tumour biology and patient survival. Results: High levels of Cav1 expression in breast cancer cell lines was strongly correlated with a TN phenotype (P&lt;0.001). Cav 1 expression was more strongly associated with the stromal subtype rather than basal subtype of TN cell lines (p=0.02).

In contrast, in human tumour tissue high levels of Cav1 correlated with the hormone receptor positive(ER) phenotype. There was also an association between Cav 1 expression and lower grade (P&lt;0.001), lower T stage (P&lt;0.001) and lower N stage (P&lt;0.001).

Cav 1 was significantly associated with improved relapse-free (RFS) and overall survival (OS) in the human cohort. On multivariate(MV) analysis Cav1 was associated with OS(HR 0.91/95% CI 0.82-1/p=0.05) but not RFS. In the subset of ER patients who only received adjuvant tamoxifen (n=199) Cav1 was also significantly associated with improved RFS and OS. MV analysis again showed this correlation to remain for OS (HR 0.81/95% CI 0.65-1/p=0.05) but not for RFS. In the TN subset (n=161) Cav1 expression did not have any survival impact. Discussion: Our results show different expression patterns of Cav1 in vitro and in vivo. TN tumors are thought to originate from the myoepithelial or stromal component of breast tissue which may explain the high levels of Cav1 in this subgroup of breast cancer cell lines. On the other hand, human tumour tissue showed an association between high Cav1 levels and ER tumours. Analysis of these macrodissected samples likely included stromal tissue surrounding the epithelial tumour cells which may explain this discrepancy.

Our data also show a correlation between high in vivo levels of Cav1 and less aggressive tumours with improved prognosis. On MV analysis Cav1 was an independent predictor of outcome in the whole cohort and in the ER subset treated with adjuvant tamoxifen only. Expression of stromal Cav1 measured by RPPA may again partly explain these findings. Further analysis with fully microdissected human breast tissue and immunohistochemical analysis of both stromal and cancer cell Cav1 expression is planned.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P3-10-23.

Phase I evaluation of SF1126, a vascular targeted PI3K inhibitor, administered twice weekly IV in patients with refractory solid tumors

2558

Background: SF1126 is composed of the pan PI3K inhibitor LY294002 conjugated to an RGD targeting peptide. It is designed to increased solubility and binding to integrins expressed on tumor vasculature. This targeted prodrug enhances tumor delivery of the active inhibitor, improving antitumor efficacy and tolerability in xenograft models. LY294002 inhibits other kinases including mTOR, DNA-PK, PIM1, PLK1, and CK2, and induces oxidative stress in cancer cells independent of its PI3K inhibition. Methods: Pts with advanced solid tumors are enrolled in sequential cohorts in standard 3+3 design. SF1126 is administered days 1, 4 weekly by 90 minute IV infusion in cycles of 4 weeks. Pharmacodynamic (PD) evaluations of PI3K pathways are being measured in PBMC, skin/hair and tumor samples as well as by 18FDG PET scans. Primary objectives are safety, establish MTD and recommended phase 2 dose. Results: 28 pts have been treated with SF1126126 across 7 dose levels of 90, 140, 180, 240, 320, 430, and 630 mg/m2. One dose limiting toxicity (DLT) was seen at the 180 mg/m2 dose, consisting of transient G3 diarrhea. No other grade 3/4 drug related toxicities have been reported. No consistent effects on blood glucose levels noted. Eleven pts showed stable disease for ≥ 8 wks, including durations of 20 wks for one GIST, 1 endometrial, and 1 prostate; 15 wks for 1 pancreatic; 11 wks for 2 GIST, 2 ovarian, and 1 CRC pt. PK: SF1126 is rapidly cleared after infusion termination. PK of active hydrolysis product (LY294002) shows t1/2 ∼1.6–2 hrs; dose proportional Cmax, achieving ∼ 21uM at 630 mg/m2; and AUC(0-t) nearly dose proportional. Mean AUC values at doses ≥ 140 mg/m2 exceed those found effective in mouse xenograft studies. PD: Compared to baseline biopsy, we observed significant inhibition of pS6 by IHC in a tumor biopsy 20 hours after the 8th dose in a pancreatic cancer pt at 240 mg/m2. Conclusions: SF1126 is well tolerated at doses up to 630 mg/m2 given twice weekly. MTD has not been reached; dose escalation continues. Clinical activity includes disease stabilization in multiple pts with refractory tumors. There is early evidence of target pathway inhibition.

[Table: see text]

Novel functional proteomics approach to defining ovarian cancer molecular heterogeneity

5502

Background: A number of clinicopathologic risk factors are used for survival prediction and clinical decision-making in epithelial ovarian cancer (EOC). Information from novel technologies such as gene arrays has not had an impact on patient management. We studied EOC protein signaling profiles to determine if their addition to accepted clinicopathologic factors improves their accuracy in predicting individual patient outcomes. Methods: We applied a novel functional proteomics technology, reverse phase protein array (RPPA), to quantify expression and activation of 42 steroid and kinase signaling pathway proteins in 106 high-grade EOCs from patients with stages 1–4 tumors managed with surgery and platinum-based chemotherapy. Cox regression analysis and a novel committee modeling approach were used to study the impact of functional proteomics on patient outcomes. Results: In a Cox model using only clinical variables, stage and residual disease were significantly related to overall survival. By adding the proteins to the clinical Cox model, two proteins that were significantly associated with overall survival on univariate analysis (phosphorylated-MAPK (p-MAPK; log rank p = 0.0047) and progesterone receptor (PR; log rank p = 0.027)) remained significant at the alpha=0.10 level (z-test p-values 0.074 and 0.034, respectively, when treated as binary variables according to martingale residual plots); as a result, these two proteins added to the predictive accuracy of the clinical survival model. However, using the novel committee modeling approach in test and validation EOC sets, a closest neighbor metric was applied to successfully define distinct proteins groups, each composed of nine proteins, that are predictive of specific survival times in patients with EOC. This granular approach to modeling is particularly suited to defining the molecular heterogeneity of EOC. Conclusions: EOC is a complex process with significant individual variability. Using novel approaches to functional proteomic study and statistical modeling, our striking finding is that distinct combinations of steroid and kinase signaling proteins are predictive markers of specific survival times in EOC.

No significant financial relationships to disclose.

Activation of the PI3K/AKT signal transduction pathway is inversely associated with estrogen receptor levels and correlates with survival in hormone receptor-positive Her2/neu-negative breast cancer

10588

Background: Hormone receptor-positive is the most common subtype of breast cancer. Despite the successes of antihormone therapy alone or combined with chemotherapy, a significant proportion of patients (30–40%) will have primary or acquired resistance to this treatment. There is a need to identify molecular markers to distinguish patients unlikely to benefit from therapy as well as novel targeted therapeutics that increase the response rate. Methods: We used a novel functional proteomics technology, reverse phase protein array (RPPA), to quantify expression and activation of 42 steroid and kinase signaling proteins in 64 hormone receptor-positive-Her2/neu-negative breast cancers from patients with stage I to III tumors managed with non-steroidal aromatase inhibitors ± chemotherapy. Unsupervised clustering analysis was used to molecularly group the tumors. Recurrence-free survival (RFS) was estimated with the Kaplan Meier product limit method and comparison was made using the Log-rank test. Correlation coefficients were used to look at the relationships between two variables. Results: Median age was 57 years (23–79). Sixteen patients (25%) had stage I tumors, 32 (50%) had stage II tumors and 16 (25%) had stage III tumors. There were two well-defined and distinct clusters of tumors: Group 1: ER high (n=25) and Group 2: PI3K/AKT activated (n=39). 3-year RFS estimates were 100% for group 1 and 59% for group 2 (p=0.04). There were thus clear inverse correlations between markers of activation of PI3K pathway and expression of ER (R for pAKT vs ER = -0.26, p=0.03). PIK3CA mutation was detected in 12/58 (21%) of hormone receptor-positive breast cancers and these tumors were found to have a proteomic signature distinct from PTEN loss with the former signature associated with a trend to improved RFS (p=0.06). Conclusion: Activation of the PI3K/AKT pathway in hormone receptor- positive-Her2/neu-negative breast cancer is inversely correlated with ER levels and associated with adverse outcome. At least in some cases, PI3K/AKT pathway activation, may be under the control of genomic aberrations. A validation set of 100 tumors treated with tamoxifen is on- going.

No significant financial relationships to disclose.

Low number of examined lymph nodes in node-negative breast cancer patients is an adverse prognostic factor

BACKGROUND

The aim of the study was to determine whether the number of lymph nodes removed at axillary dissection is associated with recurrence and survival in node-negative breast cancer (NNBC) patients.

PATIENTS AND METHODS

We retrospectively reviewed the medical records of 1606 women with pathologically node-negative T1-T3 invasive breast cancer. Median follow-up was 61 months (range 2-251). Potential prognostic factors assessed included: number of axillary lymph nodes examined, age, menopausal status, tumor size, histological type, tumor grade, estrogen receptor(ER), progesterone receptor (PR) and HER2.

RESULTS

At 5 years, relapse-free survival (RFS) rate was 85% and breast cancer-specific survival (BCSS) rate was 94%. In univariate analysis, factors significantly associated with lower RFS and BCSS were: fewer than six lymph nodes examined (RFS, P = 0.01; BCSS, P = 0.007), tumor size >2 cm, grade III, negative ER or PR. Statistically significant factors for lower RFS and BCSS in multivariate analysis were: fewer than six lymph nodes examined [RFS, hazard ratio (HR) 1.36, P = 0.029; BCSS, HR 1.87, P = 0.005], tumor size >2 cm, tumor grade III and negative PR.

CONCLUSIONS

Examination of fewer than six lymph nodes is an adverse prognostic factor in NNBC because it could lead to understaging. Six or more nodes need to be examined at axillary dissection to be confident of a node-negative status. This may be useful, in conjunction with other prognostic factors, in the assessment of NNBC patients for adjuvant systemic therapy.

Angiosarcoma of the breast

9554

Background: The purpose of this analysis is to describe the characteristics and clinical outcomes of female patients with primary breast angiosarcoma. Methods: The M. D. Anderson Cancer Center Breast Medical Oncology database was searched to identify breast angiosarcoma patients between 1965–2002. Survival outcomes were estimated by the Kaplan-Meier method. The log-rank statistic was used to compare groups. Cox proportional hazards models were used for multivariate analysis. Results: The 69 patients had a median follow up of 40 months (range, 0–413 months). Median age at diagnosis was 46. Median tumor size was 5.5 cm. Thirteen patients had received prior chest radiation (18.8%) for invasive breast carcinoma and were older than other patients (p<0.0001). Most patients underwent a simple mastectomy with (41%) or without (45%) axillary dissection. Regional metastasis to axillary lymph nodes was rare (2/28 patients). Fifteen patients (22%) received neoadjuvant chemotherapy, of whom two had a complete clinical response and 3 a partial response to doxorubicin/ifosfamide (AI); 44% received adjuvant chemotherapy, one patient received neoadjuvant and 31% adjuvant radiotherapy. There have been 38 recurrences [locoregional (20), distant (16), or combined (2)] and 27 deaths. The 5-year overall and recurrence-free survival (RFS) rates were 61% (95% CI 49–76%) and 44% (95% CI 33–58%) with estimated medians of 100 and 37 months, respectively. Survival and RFS were significantly associated with T stage (p=0.03) but not with patient age or prior radiation. Survival was also significantly worse in patients who received neoadjuvant chemotherapy administration (p=0.01) likely due to more advanced disease when this approach was used. In Cox proportional hazards models, only age at diagnosis was associated with RFS. Of 29 patients treated with chemotherapy at relapse, there were 4 complete and 10 partial responses (48% responses) with AI or a gemcitabine-taxane combination. Conclusion: Breast angiosarcoma is frequently advanced at diagnosis with a tendency for locoregional recurrence. In light of this and its observed chemosensitivity, a multidisciplinary therapeutic approach with chemo- radiotherapy and surgical resection should be considered. Initial chemotherapy for neoadjuvant and metastatic disease is effective.

No significant financial relationships to disclose.

Proteomic prediction in hormone receptor-positive breast cancer

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Background: Hormone receptor-positive breast cancer (HR+BC) is heterogeneous. Attempts to use transcriptional analysis such as Oncotype Dx facilitate therapy planning but fail to identify patients who will relapse or potential therapy targets. Methods: We used reverse phase protein lysate arrays and Microvigene software to quantify expression of estrogen receptor (ERα) and 36 total/activated components of the HER2, phosphatidylinositol-3-kinase (PI3K), mitogen-activated protein kinase (MAPK), and STAT pathways in 64 HR+BCs and 40 breast cancer cell lines. Clustering was performed with Xcluster and Treeview. Results: 47/64 HR+BC patients were treated with adjuvant hormone therapy and 43/64 with chemotherapy. There were 12 recurrences including 5 patients diagnosed with metastases within 0–3 months of diagnosis. Unsupervised analysis using the expression of all 37 proteins revealed two large subclusters of HR+BCs. One large cluster was composed of tumors with lower ERα expression levels and was driven by an antibody group composed mostly of phosphoproteins indicative of activated growth factor signaling pathways. Thus, there were significant inverse correlations between ERα expression and the expression and activation of components of the PI3K/MAPK pathways including EGFR, src, AKT, 4EBP1, and PKCα (p≤0.05 for each). Similar inverse correlations were seen in 40 assayed breast cancer cell lines. The clinicoproteomic predictors of relapse among HR+BCs were nuclear grade (p=0.001), low expression of ERα (p=0.04), low p38 phosphorylation (p=0.02), and high p53 (p=0.02). There also was a trend (p≤0.1) to the association of low MAPK and S6 phosphorylation, low p27, and high cyclin B1 with relapse. Using these antibodies to perform a supervised analysis, we found a small group of p53-high, cyclin B1-high, ERα-low HR+BCs with a 75% likelihood of relapse, significantly greater than in other tumors (p<0.003). Since 10/12 relapses occurred in 26 grade 3 tumors, we searched for and found a ‘grade 3’ HR+BC 6 antibody signature associated with a recurrence-free survival at 20 months of 17% compared to 100% in other patients (p=0.002). Conclusion: Although patient numbers are small and the findings require validation, kinase signaling profiles have potential in breast cancer prediction.

No significant financial relationships to disclose.

Biphasic metaplastic sarcomatoid carcinoma of the breast

BACKGROUND

Breast biphasic metaplastic sarcomatoid carcinoma (MSC) is rare and aggressive. We analyzed 100 patients treated at M. D. Anderson Cancer Center (MDACC) with 213 MSC and 98 carcinosarcoma patients identified through the Surveillance, Epidemiology and End-Results (SEER) database to describe clinical and pathologic characteristics.

PATIENTS AND METHODS

We searched the MDACC (1985-2001) and SEER databases (1988-2001) for breast MSC and carcinosarcoma patients.

RESULTS

We identified 100 MDACC MSC patients: 66% had node-negative disease and 6% distant metastases at presentation. Median recurrence-free survival (RFS) of 94 patients with stages I-III disease was 74 months (range 3-74), with 52% 5-year RFS [95% confidence interval (CI) 0.42-0.63]. Median overall survival in these patients was not reached, with 64% 5-year survival (95% CI 0.54-0.75). The initial stage of the tumor, but not use of adjuvant chemo- or radiotherapy, had a strong association with outcome. The pathologic complete response rate to neoadjuvant chemotherapy was 10%. Median survival from the time of recurrent disease was 14 months (range 1-55). Tumors were usually hormone receptor- and HER2/neu-negative. SEER data were consistent with MDACC findings.

CONCLUSIONS

Breast MSC and carcinosarcoma are aggressive, treatment-refractory tumors with shared clinical features and outcome similar to poorly differentiated receptor-negative adenocarcinomas. New therapeutic agents are needed.

Ovarian cancer: Homeobox genes, autocrine/paracrine growth, and kinase signaling

Epithelial ovarian cancer, the fourth leading cause of cancer deaths in American women, is currently classified by surgical and histologic appearance. However, the predictive value of this classification is limited. The risk of epithelial ovarian cancer increases with the number of ovulatory events. It is now thought that different ovarian tumors are derived from a single ovarian surface epithelial precursor cell with the degree and pattern of differentiation determined by combinatorial expression of homeobox genes normally involved in differentiation of the female genital tract. This aberrant differentiation occurs in association with histology-specific genomic aberrations, genomic instability, and resultant chromosomal changes, and may be triggered by prolonged abnormal or excessive exposure of surface epithelial cells to autocrine/paracrine stimulation by sex steroids and other growth factors. As the disease progresses, activation of kinase pathways and continued abnormal autocrine/paracrine stimulation contribute to genomic instability but also identify potential targets for novel therapeutic intervention.

Adjuvant therapy for breast cancer

Significant progress has been made in the last 30 years in the adjuvant hormonal and chemo-therapeutic treatments of breast cancer. Currently, several cytotoxic agents are available for use including anthracyclines, taxanes, and cyclophosphamide, methotrexate and 5-fluorouracil (CMF) and a new class of hormonal agents, aromatase inhibitors were introduced. A greater than 50% improvement in risk of relapse and 25% absolute overall survival advantage is presently realistic for many women with lymph node-positive breast cancer who receive adjuvant therapy. Aromatase inhibitors (AI) now constitute a superior alternative to tamoxifen as adjuvant hormonal therapy in postmenopausal women with hormone receptor-positive breast cancer. Extended hormonal therapy with letrozole after completion of five-years of tamoxifen has been shown to improve survival and reduce late relapses. It has also been established that anthracycline containing combination chemotherapy is superior to CMF if the number of cycles is kept the same. Inclusion of a taxane in an anthracycline-based regimen has further improved efficacy. The schedule of administration of drugs, particularly of paclitaxel, also appears to have an impact on efficacy. On the other hand, increasing the dose of cyclophosphamide or anthracyclines above the standard dose do not appear to improve the efficacy of these regimens, whereas substandard dose are clearly inferior. Currently there are several highly effective adjuvant chemotherapy regimens, however there is no single best treatment, let alone a universally effective one. Tamoxifen was the first truly molecularly targeted agent to be used in the treatment of cancer though it took some time to understand that its benefits are restricted to hormone receptor-positive cancers only. Clinical experience shows that similar principals apply to adjuvant chemotherapy as well. Only a subset of patients with micro-metastatic disease benefit from cytotoxic therapy. A major current research effort is focused on the discovery of molecular markers that could predict who will benefit from what particular type of chemotherapy. In the near future, important clinical advances will come from the incorporation of trastuzumab into adjuvant chemotherapy regimens for patients with HER-2 amplified tumors. Results from several large randomized studies are expected shortly and will define the use of trastuzumab in this clinical setting.

Lower dose capecitabine has a more favorable therapeutic index in metastatic breast cancer: retrospective analysis of patients treated at M. D. Anderson Cancer Center and a review of capecitabine toxicity in the literature

BACKGROUND

Capecitabine is active against anthracycline- and taxane-pretreated metastatic breast cancer. Post-marketing use of capecitabine at the FDA-approved dose (2500 mg/m2/day) leads to unacceptable toxicity in many patients. Dose reductions anecdotally improve tolerability without compromising efficacy. This retrospective analysis was designed to verify these anecdotal reports.

PATIENTS AND METHODS

We retrospectively reviewed the records of 141 consecutive patients with metastatic breast cancer identified from pharmacy records as receiving capecitabine outside of a clinical trial between May 1998 and February 1999. Responses were defined as clinical improvement (ID), stabilization of disease (SD) for 6 weeks or longer, or progression (PD). Patients were grouped according to the starting dose level of capecitabine: A=2500+/-5% (dose range 2385-2560) mg/m2/day; B=2250+/-5% (range 2130-2350) mg/m2/day; C < or = 2000+5% (range 1000-2100) mg/m2/day. We also reviewed the safety profile of capecitabine at these doses and performed a safety review of capecitabine in phase II and III metastatic breast and colorectal cancer trials.

RESULTS

Clinical data were available for 113 patients (105 for response, 106 for toxicity). The median age was 52.5 years and the mean number of prior metastatic chemotherapy regimens was 2 (range 0-7). The mean capecitabine starting dose was 2220 mg/m2/day and the median number of cycles administered was 4 (range 1-19). The mean tolerated dose was 2040 mg/m2/day (range 960-2670). Grade 3/4 toxic effects at dose levels A, B and C, respectively, included palmar-plantar erythrodysesthesia (33%, 63%, 20%), diarrhea (13%, 12%, 3%), stomatitis (8%, 0%, 3%), and nausea/vomiting (4%, 6%, 5%). Forty per cent of all patients required capecitabine dose reductions; fewer patients treated with 2000 mg/m2/day required dose modification (28%). Five per cent of the patients required discontinuation of capecitabine owing to toxicity. Patients started at the lowest doses of capecitabine did not have poorer response rates or shorter time to progression.

CONCLUSIONS

This retrospective analysis supports a starting dose of 2000 mg/m2/day because of its superior therapeutic index; however, patients may still have toxic effects and individualization of dosing is necessary. A phase III, multicenter, randomized study to establish the safety and efficacy of different doses of capecitabine is urgently needed.

Chemotherapy options for the elderly patient with advanced non-small cell lung cancer

Combination chemotherapy has been shown to improve overall survival compared with best supportive care in patients with advanced non-small cell lung cancer (NSCLC). The survival advantage is modest and was initially demonstrated with cisplatin-containing regimens in a large meta-analysis of randomized trials reported in 1995. Newer chemotherapy combinations have been shown to be better tolerated than older cisplatin-based combinations, and some trials have also shown greater efficacy and survival benefits with these newer combinations. Combination chemotherapy is, therefore, the currently accepted standard of care for patients with good performance statuses aged less than 70 years with advanced NSCLC. However, there are limited data from clinical trials to support the use of combination chemotherapy in elderly patients over 70 years of age with advanced NSCLC. Subgroup analyses of large randomized phase III trials suggest that elderly patients with good performance statuses do as well as younger patients treated with combination chemotherapy. There are few randomized trials reported that evaluate chemotherapy in patients aged greater than 70 years only. Based on data from trials performed by an Italian group, single-agent vinorelbine has been shown to have significant activity in elderly patients with advanced NSCLC and to be well tolerated by those patients with Eastern Cooperative Oncology Group performance statuses of two or less, with associated improvements in measures of global health.