Disparity between Ki67 measurements and tumor gene expression tests in patients with hormone-sensitive early breast cancer from the OPTIMA preliminary trial

567

Background: Tumor gene expression tests are increasingly used in breast cancer management. The Ki67 biomarker has been proposed as an inexpensive alternative for making chemotherapy decisions, has demonstrated utility for determination of endocrine therapy responsiveness and is included in the FDA license for adjuvant abemaciclib. We have compared Ki67 measurements with tumor gene expression test results for patients included in the OPTIMA prelim trial. Methods: We compared Ki67 %staining with the results of Oncotype DX, Prosigna and MammaPrint performed by the test vendor. Ki67 was determined in a single laboratory on triplicate tissue micro-arrays using quantitative image analysis including a 10% manual quality control check. We used kappa statistics to measure agreement between tests, divided into groups using the pre-defined test score boundaries for high vs. not high risk. Results: Data were available for 259 patients. Using ≥20% staining to define a high Ki67 score, kappa values (95% CI) for agreement with Prosigna were: 0.39 (0.28-0.49); Oncotype DX: 0.27 (0.18-0.36); and MammaPrint: 0.38 (0.27-0.49). Kappa values <0.2 are conventionally interpreted as showing slight agreement and 0.21-0.4 as fair agreement. A detailed breakdown of the comparisons of Ki67 with Prosigna and Oncotype DX is tabulated. Conclusions: Agreement between Ki67 and tumor gene expression tests is limited. Therefore, Ki67 values cannot accurately be used to reflect any of the molecular scores assessed here, all of which are well validated prognostic biomarkers. The use of Ki67 to determine suitability for adjuvant chemotherapy requires validation before it can replace the existing tests. Tumor gene expression tests may prove superior to Ki67 for the identification of patients likely to benefit from adjuvant abemaciclib. OPTIMA prelim is registered as ISRCTN42400492 and funded by the UK NIHR Health Technology Assessment Programme, award number 10/34/01. Clinical trial information: ISRCTN42400492. [Table: see text]

Comparative survival analysis of multiparametric tests-when molecular tests disagree-A TEAM Pathology study

Multiparametric assays for risk stratification are widely used in the management of both node negative and node positive hormone receptor positive invasive breast cancer. Recent data from multiple sources suggests that different tests may provide different risk estimates at the individual patient level. The TEAM pathology study consists of 3284 postmenopausal ER+ve breast cancers treated with endocrine therapy Using genes comprising the following multi-parametric tests OncotypeDx®, Prosigna™ and MammaPrint® signatures were trained to recapitulate true assay results. Patients were then classified into risk groups and survival assessed. Whilst likelihood χ2 ratios suggested limited value for combining tests, Kaplan-Meier and LogRank tests within risk groups suggested combinations of tests provided statistically significant stratification of potential clinical value. Paradoxically whilst Prosigna-trained results stratified Oncotype-trained subgroups across low and intermediate risk categories, only intermediate risk Prosigna-trained cases were further stratified by Oncotype-trained results. Both Oncotype-trained and Prosigna-trained results further stratified MammaPrint-trained low risk cases, and MammaPrint-trained results also stratified Oncotype-trained low and intermediate risk groups but not Prosigna-trained results. Comparisons between existing multiparametric tests are challenging, and evidence on discordance between tests in risk stratification presents further dilemmas. Detailed analysis of the TEAM pathology study suggests a complex inter-relationship between test results in the same patient cohorts which requires careful evaluation regarding test utility. Further prognostic improvement appears both desirable and achievable.

Abstract PD1-11: Mature survival update of the double-blind placebo-controlled randomised phase II PAKT trial of first-line capivasertib plus paclitaxel for metastatic triple-negative breast cancer

Background: In the PAKT study, addition of the oral AKT inhibitor capivasertib to 1st-line paclitaxel therapy for metastatic TNBC resulted in significantly longer progression-free survival (PFS; primary endpoint; Schmid, J Clin Oncol 2020). The stratified PFS hazard ratio was 0.74 (95% CI, 0.50-1.08; one-sided P=0.06; predefined significance level of 0.10, one-sided; median PFS 5.9 vs 4.2 months with capivasertib vs placebo). Overall survival (OS) results were immature at the primary analysis with 53% of events but suggested long OS with capivasertib (HR, 0.61; 95% CI, 0.37-0.99; two-sided P=0.04). Here we report final results.

Methods: This double-blind, placebo-controlled, randomised phase II trial, recruited women with untreated, metastatic TNBC. Total of 140 patients were randomly assigned (1:1) to paclitaxel 90mg/m2 (days 1, 8, 15) with either capivasertib (400mg twice daily) or placebo (days 2-5, 9-12, 16-19) every 28 days until disease progression or unacceptable toxicity. The primary endpoint was PFS. Secondary endpoints included OS in the ITT population and in patients with and without PIK3CA/AKT1/PTEN-alterations.

Results: With a median F/U of 40.0 months, median OS was longer in the capivasertib arm (19.1 vs 13.5 months, stratified HR 0.70, 95% CI 0.47-1.05, p=0.085). In contrast to the earlier analysis, no meaningful differences were seen in terms of benefit with capivasertib between patients with or without alterations of PIK3CA/AKT1/PTEN. Median OS numerically favoured capivasertib vs placebo both in the PIK3CA/AKT1/PTEN-altered (stratified HR 0.58, 95% CI 0.21-1.58, p=0.290) and PIK3CA/AKT1/PTEN non-altered subgroup (stratified HR 0.74, 95% CI 0.47-1.18, p=0.207). The safety profile of capivasertib plus paclitaxel was unchanged.

Conclusions: Final OS results show a numerical trend favouring capivasertib; effects were observed regardless of PIK3CA/AKT1/PTEN alterations. Consistent with the previously observed PFS benefit, these findings support further evaluation of first-line Capivasertib plus paclitaxel for metastatic TNBC in the ongoing Capitello290 randomised phase III trial in patients with and without PIK3CA/AKT1/PTEN alterations.

Citation Format: Peter Schmid, Jacinta Abraham, Stephen Chan, Adrian Murray Brunt, Gia Nemsadze, Richard D Baird, Yeon Hee Park, Peter Hall, Timothy Perren, Robert C Stein, László Mangel, Jean-Marc Ferrero, Melissa Phillips, John Conibear, Javier Cortes, Andrew Foxley, Elza de Bruin, Robert McEwen, Myria Nikolaou, Daniel Stetson, Brian Dougherty, Aaron Prendergast, Max McLaughlin-Callan, Matthew Burgess, Cheryl Lawrence, Hayley Cartwright, Kelly Mousa, Nicholas Turner, Duncan Wheatley. Mature survival update of the double-blind placebo-controlled randomised phase II PAKT trial of first-line capivasertib plus paclitaxel for metastatic triple-negative breast cancer [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PD1-11.

Tumour profiling tests to guide adjuvant chemotherapy decisions in early breast cancer: a systematic review and economic analysis

BACKGROUND

Breast cancer and its treatment can have an impact on health-related quality of life and survival. Tumour profiling tests aim to identify whether or not women need chemotherapy owing to their risk of relapse.

OBJECTIVES

To conduct a systematic review of the effectiveness and cost-effectiveness of the tumour profiling tests oncotype DX^® (Genomic Health, Inc., Redwood City, CA, USA), MammaPrint^® (Agendia, Inc., Amsterdam, the Netherlands), Prosigna^® (NanoString Technologies, Inc., Seattle, WA, USA), EndoPredict^® (Myriad Genetics Ltd, London, UK) and immunohistochemistry 4 (IHC4). To develop a health economic model to assess the cost-effectiveness of these tests compared with clinical tools to guide the use of adjuvant chemotherapy in early-stage breast cancer from the perspective of the NHS and Personal Social Services.

DESIGN

A systematic review and health economic analysis were conducted.

REVIEW METHODS

The systematic review was partially an update of a 2013 review. Nine databases were searched in February 2017. The review included studies assessing clinical effectiveness in people with oestrogen receptor-positive, human epidermal growth factor receptor 2-negative, stage I or II cancer with zero to three positive lymph nodes. The economic analysis included a review of existing analyses and the development of a de novo model.

RESULTS

A total of 153 studies were identified. Only one completed randomised controlled trial (RCT) using a tumour profiling test in clinical practice was identified: Microarray In Node-negative Disease may Avoid ChemoTherapy (MINDACT) for MammaPrint. Other studies suggest that all the tests can provide information on the risk of relapse; however, results were more varied in lymph node-positive (LN+) patients than in lymph node-negative (LN0) patients. There is limited and varying evidence that oncotype DX and MammaPrint can predict benefit from chemotherapy. The net change in the percentage of patients with a chemotherapy recommendation or decision pre/post test ranged from an increase of 1% to a decrease of 23% among UK studies and a decrease of 0% to 64% across European studies. The health economic analysis suggests that the incremental cost-effectiveness ratios for the tests versus current practice are broadly favourable for the following scenarios: (1) oncotype DX, for the LN0 subgroup with a Nottingham Prognostic Index (NPI) of > 3.4 and the one to three positive lymph nodes (LN1-3) subgroup (if a predictive benefit is assumed); (2) IHC4 plus clinical factors (IHC4+C), for all patient subgroups; (3) Prosigna, for the LN0 subgroup with a NPI of > 3.4 and the LN1-3 subgroup; (4) EndoPredict Clinical, for the LN1-3 subgroup only; and (5) MammaPrint, for no subgroups.

LIMITATIONS

There was only one completed RCT using a tumour profiling test in clinical practice. Except for oncotype DX in the LN0 group with a NPI score of > 3.4 (clinical intermediate risk), evidence surrounding pre- and post-test chemotherapy probabilities is subject to considerable uncertainty. There is uncertainty regarding whether or not oncotype DX and MammaPrint are predictive of chemotherapy benefit. The MammaPrint analysis uses a different data source to the other four tests. The Translational substudy of the Arimidex, Tamoxifen, Alone or in Combination (TransATAC) study (used in the economic modelling) has a number of limitations.

CONCLUSIONS

The review suggests that all the tests can provide prognostic information on the risk of relapse; results were more varied in LN+ patients than in LN0 patients. There is limited and varying evidence that oncotype DX and MammaPrint are predictive of chemotherapy benefit. Health economic analyses indicate that some tests may have a favourable cost-effectiveness profile for certain patient subgroups; all estimates are subject to uncertainty. More evidence is needed on the prediction of chemotherapy benefit, long-term impacts and changes in UK pre-/post-chemotherapy decisions.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42017059561.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Computational approaches to support comparative analysis of multiparametric tests: Modelling versus Training

Multiparametric assays for risk stratification are widely used in the management of breast cancer, with applications being developed for a number of other cancer settings. Recent data from multiple sources suggests that different tests may provide different risk estimates at the individual patient level. There is an increasing need for robust methods to support cost effective comparisons of test performance in multiple settings. The derivation of similar risk classifications using genes comprising the following multi-parametric tests Oncotype DX^® (Genomic Health.), Prosigna^™ (NanoString Technologies, Inc.), MammaPrint^® (Agendia Inc.) was performed using different computational approaches. Results were compared to the actual test results. Two widely used approaches were applied, firstly computational “modelling” of test results using published algorithms and secondly a “training” approach which used reference results from the commercially supplied tests. We demonstrate the potential for errors to arise when using a “modelling” approach without reference to real world test results. Simultaneously we show that a “training” approach can provide a highly cost-effective solution to the development of real-world comparisons between different multigene signatures. Comparisons between existing multiparametric tests is challenging, and evidence on discordance between tests in risk stratification presents further dilemmas. We present an approach, modelled in breast cancer, which can provide health care providers and researchers with the potential to perform robust and meaningful comparisons between multigene tests in a cost-effective manner. We demonstrate that whilst viable estimates of gene signatures can be derived from modelling approaches, in our study using a training approach allowed a close approximation to true signature results.

Strategies to Improve Recruitment to a De-escalation Trial: A Mixed-Methods Study of the OPTIMA Prelim Trial in Early Breast Cancer

AIMS

De-escalation trials are challenging and sometimes may fail due to poor recruitment. The OPTIMA Prelim randomised controlled trial (ISRCTN42400492) randomised patients with early stage breast cancer to chemotherapy versus 'test-directed' chemotherapy, with a possible outcome of no chemotherapy, which could confer less treatment relative to routine practice. Despite encountering challenges, OPTIMA Prelim reached its recruitment target ahead of schedule. This study reports the root causes of recruitment challenges and the strategies used to successfully overcome them.

MATERIALS AND METHODS

A mixed-methods recruitment intervention (QuinteT Recruitment Intervention) was used to investigate the recruitment difficulties and feedback findings to inform interventions and optimise ongoing recruitment. Quantitative site-level recruitment data, audio-recorded recruitment appointments (n = 46), qualitative interviews (n = 22) with trialists/recruiting staff (oncologists/nurses) and patient-facing documentation were analysed using descriptive, thematic and conversation analyses. Findings were triangulated to inform a 'plan of action' to optimise recruitment.

RESULTS

Despite best intentions, oncologists' routine practices complicated recruitment. Discomfort about deviating from the usual practice of recommending chemotherapy according to tumour clinicopathological features meant that not all eligible patients were approached. Audio-recorded recruitment appointments revealed how routine practices undermined recruitment. A tendency to justify chemotherapy provision before presenting the randomised controlled trial and subtly indicating that chemotherapy would be more/less beneficial undermined equipoise and made it difficult for patients to engage with OPTIMA Prelim. To tackle these challenges, individual and group recruiter feedback focussed on communication issues and vignettes of eligible patients were discussed to address discomforts around approaching patients. 'Tips' documents concerning structuring discussions and conveying equipoise were disseminated across sites, together with revisions to the Patient Information Sheet.

CONCLUSIONS

This is the first study illuminating the tension between oncologists' routine practices and recruitment to de-escalation trials. Although time and resources are required, these challenges can be addressed through specific feedback and training as the trial is underway.

Abstract OT3-17-01: OPTIMA: A prospective randomized trial to validate the clinical utility and cost-effectiveness of gene expression test-directed chemotherapy decisions in mostly node-positive early breast cancer

Background: Multi-parameter tumour gene expression assays (MPAs) are widely used to estimate individual patient risk and to guide chemotherapy use in hormone-sensitive, HER2-negative early breast cancer. The TAILORx trial supports MPA use in a node-negative population. Evidence in node-positive breast cancer is limited. OPTIMA (Optimal Personalised Treatment of early breast cancer usIng Multi-parameter Analysis) (ISRCTN42400492) is a prospective international randomised controlled trial (RCT) designed to validate MPA’s as predictors of chemotherapy sensitivity in a largely node-positive breast cancer population.

Methods: OPTIMA is a partially blinded study with an adaptive two-stage design. The main eligibility criteria are women and men age 40 or older with resected ER-positive, HER2-negative invasive breast cancer and up to 9 involved axillary lymph nodes. Randomisation is to standard management (chemotherapy and endocrine therapy) or to MPA-directed treatment using the Prosigna (PAM50) test. Those with a Prosigna tumour Score (ROR_PT) &gt;60 receive standard management whilst those with a low score (≤60) are treated with endocrine therapy alone. Endocrine therapy for pre-menopausal women includes ovarian suppression. Prosigna tests are currently performed only for participants randomised to MPA-directed treatment. More than 1 tumour may be tested if participants have multi-focal tumours with discordant features and/or are considered clinically significant. The co-primary outcomes are: (1) Invasive Disease Free Survival (IDFS) and (2) cost-effectiveness. Secondary outcomes include IDFS in patients with low-score tumours and quality of life. Recruitment of 4500 patients over 5 years will permit demonstration of 3% non-inferiority of test-directed treatment, assuming 5-year IDFS of 85% with standard management. An integrated qualitative recruitment study addresses challenges to consent and recruitment, building on experience from the feasibility study which found that a multidisciplinary approach is important for recruitment success.

Results: The OPTIMA main trial opened in January 2017. Overall recruitment as of 1 July 2019 was 1123 (1100 from UK, 13 from Norway); 91% had axillary node macro-metastases. Median time from consent to treatment allocation was 12 days (interquartile range 10-14 days). The withdrawal rate from trial treatment is 3%; 50% of these continue with follow up. Prosigna tests have been performed on 608 tumours for 549 participants; 59% were luminal A, 38% were luminal B and 3% non-luminal (6 patients with non-luminal tumours [1% overall] were ineligible on receptor retesting). Of the 53 (10%) participants with &gt;1 tumour tested, 3 (6%) had discordant scores only, 7 (13%) had discordant subtypes only and 8 (15%) had both discordant scores and subtypes. Two thirds of the MPA-directed arm participants have been allocated to endocrine therapy only. The test failure rate is &lt;1%.

Conclusion: OPTIMA is one of two large scale prospective trials validating the use of test-guided chemotherapy decisions in node-positive early breast cancer. It is expected to have a global impact on breast cancer treatment.

Funding: OPTIMA is funded by the UK NIHR HTA Programme (10/34/501). Views expressed are those of the authors and not those of the HTA Programme, NIHR, NHS or the Department of Health.

Trial Inquiries: OPTIMA@warwick.ac.uk

Citation Format: Robert C Stein, Andrea Marshall, Andreas Makris, Luke Hughes-Davies, Iain R MacPherson, Carmel Conefrey, Leila Rooshenas, Sarah E Pinder, Abeer M Shaaban, Bjørn Naume, David A Cameron, Daniel W Rea, Helena M Earl, Christopher J Poole, Peter S Hall, Georgina Dotchin, Stuart A McIntosh, Victoria Harmer, Adrienne Morgan, Bethany Shinkins, Nigel Stallard, Christopher McCabe, Jenny L Donovan, John MS Bartlett, Janet A Dunn. OPTIMA: A prospective randomized trial to validate the clinical utility and cost-effectiveness of gene expression test-directed chemotherapy decisions in mostly node-positive early breast cancer [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr OT3-17-01.

Capivasertib Plus Paclitaxel Versus Placebo Plus Paclitaxel As First-Line Therapy for Metastatic Triple-Negative Breast Cancer: The PAKT Trial

PURPOSE

The phosphatidylinositol 3-kinase (PI3K)/AKT signaling pathway is frequently activated in triple-negative breast cancer (TNBC). The AKT inhibitor capivasertib has shown preclinical activity in TNBC models, and drug sensitivity has been associated with activation of PI3K or AKT and/or deletions of PTEN. The PAKT trial was designed to evaluate the safety and efficacy of adding capivasertib to paclitaxel as first-line therapy for TNBC.

PATIENTS AND METHODS

This double-blind, placebo-controlled, randomized phase II trial recruited women with untreated metastatic TNBC. A total of 140 patients were randomly assigned (1:1) to paclitaxel 90 mg/m² (days 1, 8, 15) with either capivasertib (400 mg twice daily) or placebo (days 2-5, 9-12, 16-19) every 28 days until disease progression or unacceptable toxicity. The primary end point was progression-free survival (PFS). Secondary end points included overall survival (OS), PFS and OS in the subgroup with PIK3CA/AKT1/PTEN alterations, tumor response, and safety.

RESULTS

Median PFS was 5.9 months with capivasertib plus paclitaxel and 4.2 months with placebo plus paclitaxel (hazard ratio [HR], 0.74; 95% CI, 0.50 to 1.08; 1-sided P = .06 [predefined significance level, 1-sided P = .10]). Median OS was 19.1 months with capivasertib plus paclitaxel and 12.6 months with placebo plus paclitaxel (HR, 0.61; 95% CI, 0.37 to 0.99; 2-sided P = .04). In patients with PIK3CA/AKT1/PTEN-altered tumors (n = 28), median PFS was 9.3 months with capivasertib plus paclitaxel and 3.7 months with placebo plus paclitaxel (HR, 0.30; 95% CI, 0.11 to 0.79; 2-sided P = .01). The most common grade ≥ 3 adverse events in those treated with capivasertib plus paclitaxel versus placebo plus paclitaxel, respectively, were diarrhea (13% v 1%), infection (4% v 1%), neutropenia (3% v 3%), rash (4% v 0%), and fatigue (4% v 0%).

CONCLUSION

Addition of the AKT inhibitor capivasertib to first-line paclitaxel therapy for TNBC resulted in significantly longer PFS and OS. Benefits were more pronounced in patients with PIK3CA/AKT1/PTEN-altered tumors. Capivasertib warrants further investigation for treatment of TNBC.

Abstract OT1-05-02: OPTIMA: A prospective randomized trial to validate the clinical utility and cost-effectiveness of gene expression test-directed chemotherapy decisions in high clinical risk early breast cancer

Background:Multi-parameter tumour gene expression assays (MPAs) are widely used to estimate individual patient residual risk and to guide chemotherapy use in hormone-sensitive, HER2-negative early breast cancer. The TAILORx trial supports MPA use in a node-negative population. Evidence for MPA use in node-positive breast cancer is limited. OPTIMA (Optimal Personalised Treatment of early breast cancer usIng Multi-parameter Analysis) (ISRCTN42400492) aims to validate MPAs as predictors of chemotherapy sensitivity in a largely node-positive breast cancer population where prospective RCT (Randomised Controlled Trial) evidence is lacking.

Methods: OPTIMA is a partially blinded multi-center RCT with an adaptive two-stage design. The main eligibility criteria are women and men age 40 or older with resected ER-positive, HER2-negative invasive breast cancer and up to 9 involved axillary lymph nodes. Randomisation is to standard management (chemotherapy and endocrine therapy) or to MPA-directed treatment using the Prosigna (PAM50) test. Those with a Prosigna tumour score (ROR_PT) &gt;60 receive standard management whilst those with a low score (≤60) are treated with endocrine therapy alone. Endocrine therapy for pre-menopausal women includes ovarian suppression. The co-primary outcomes are (1) Invasive Disease Free Survival (IDFS) and (2) cost-effectiveness of test-directed treatment. Secondary outcomes include IDFS in patients with low-score tumours and quality of life. An integrated qualitative recruitment study addresses challenges to consent and recruitment and will build on experience from the feasibility study that a multidisciplinary approach at sites is important for recruitment success. Tumour blocks will be banked to allow evaluation of additional MPA technologies. Recruitment of 4500 patients over 5 years will permit demonstration of 3% non-inferiority of test-directed treatment, assuming 5-year IDFS of 85% with standard management, equivalent to a HR of 1.22. Inclusion of patients from the feasibility study will increase the power to test for non-inferiority.

Results: The OPTIMA main trial opened in January 2017. Overall recruitment (including the feasibility study) will reach 1000 in August 2018. Recruitment in Norway will commence in July 2018. Characteristics of the OPTIMA main participants recruited to 31st May 2018 are shown in the table.

Main study patient characteristicsCharacteristic %Median age in years (range)57 (40-80) Menopause statusPre34 Post66 Male1Tumour size&lt;30mm58 &gt;=30mm42Node statuspN04 pN1mi(sn)7 pN1(sn)20 pN155 pN214Historic grade16 258 336

Conclusion: OPTIMA is one of two large scale prospective trials validating the use of test-guided chemotherapy decisions in node-positive early breast cancer. It is expected to have a global impact on breast cancer treatment. Experience from the preliminary study and close engagement with centres will aid trial success.

Funding: OPTIMA is funded by the UK NIHR HTA Programme (10/34/501). Views expressed are those of the authors and not those of the HTA Programme, NIHR, NHS or the DoH.

Citation Format: Stein RC, Hughes-Davies L, Makris A, Macpherson IR, Conefrey C, Rooshenas L, Pinder SE, Thomas J, Hall PS, Cameron DA, Earl HM, Naume B, Poole CJ, Rea DW, MacIntosh SA, Harmer V, Morgan A, Hulme C, McCabe C, Stallard N, Higgins H, Donovan JL, Bartlett JM, Marshall A, Dunn JA. OPTIMA: A prospective randomized trial to validate the clinical utility and cost-effectiveness of gene expression test-directed chemotherapy decisions in high clinical risk early breast cancer [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 OT1-05-02.

Randomized Phase II Study Evaluating Palbociclib in Addition to Letrozole as Neoadjuvant Therapy in Estrogen Receptor-Positive Early Breast Cancer: PALLET Trial

PURPOSE

CDK4/6 inhibitors are used to treat estrogen receptor (ER)-positive metastatic breast cancer (BC) in combination with endocrine therapy. PALLET is a phase II randomized trial that evaluated the effects of combination palbociclib plus letrozole as neoadjuvant therapy.

PATIENTS AND METHODS

Postmenopausal women with ER-positive primary BC and tumors greater than or equal to 2.0 cm were randomly assigned 3:2:2:2 to letrozole (2.5 mg/d) for 14 weeks (A); letrozole for 2 weeks, then palbociclib plus letrozole to 14 weeks (B); palbociclib for 2 weeks, then palbociclib plus letrozole to 14 weeks (C); or palbociclib plus letrozole for 14 weeks. Palbociclib 125 mg/d was administered orally on a 21-days-on, 7-days-off schedule. Core-cut biopsies were taken at baseline and 2 and 14 weeks. Coprimary end points for letrozole versus palbociclib plus letrozole groups (A v B + C + D) were change in Ki-67 (protein encoded by the  MKI67 gene; immunohistochemistry) between baseline and 14 weeks and clinical response (ordinal and ultrasound) after 14 weeks. Complete cell-cycle arrest was defined as Ki-67 less than or equal to 2.7%. Apoptosis was characterized by cleaved poly (ADP-ribose) polymerase.

RESULTS

Three hundred seven patients were recruited. Clinical response was not significantly different between palbociclib plus letrozole and letrozole groups ( P = .20; complete response + partial response, 54.3% v 49.5%), and progressive disease was 3.2% versus 5.4%, respectively. Median log-fold change in Ki-67 was greater with palbociclib plus letrozole compared with letrozole (-4.1 v -2.2; P < .001) in the 190 evaluable patients (61.9%), corresponding to a geometric mean change of -97.4% versus -88.5%. More patients on palbociclib plus letrozole achieved complete cell-cycle arrest (90% v 59%; P < .001). Median log-fold change (suppression) of cleaved poly (ADP-ribose) polymerase was greater with palbociclib plus letrozole versus letrozole (-0.80 v -0.42; P < .001). More patients had grade 3 or greater toxicity on palbociclib plus letrozole (49.8% v 17.0%; P < .001) mainly because of asymptomatic neutropenia.

CONCLUSION

Adding palbociclib to letrozole significantly enhanced the suppression of malignant cell proliferation (Ki-67) in primary ER-positive BC, but did not increase the clinical response rate over 14 weeks, which was possibly related to a concurrent reduction in apoptosis.

Abstract OT1-06-01: OPTIMA: A prospective randomized trial to validate the predictive utility and cost-effectiveness of gene expression test-directed chemotherapy decisions in early breast cancer

Background: Multi-parameter gene expression assays (MPAs) are widely used to estimate individual patient residual risk in hormone-sensitive HER2-negative node-negative early breast cancer, allowing patients with low risk to safely avoid chemotherapy. Evidence for MPA use in node-positive breast cancer is limited. OPTIMA (Optimal Personalised Treatment of early breast cancer usIng Multi-parameter Analysis) aims to validate MPA's as predictors of chemotherapy sensitivity in a largely node-positive breast cancer population.

Methods: OPTIMA is a partially blinded multi-center, phase 3 randomized controlled trial with an adaptive two-stage design. The main eligibility criteria are women or men aged 40 or older with resected ER-positive, HER2-negative breast cancer and up to 9 involved axillary lymph nodes. Randomization is to standard management (chemotherapy and endocrine therapy) or to MPA-directed treatment. Those with a “high risk” tumor MPA score receive standard management whilst those at “low risk” are treated with endocrine therapy alone. The preliminary phase (OPTIMA prelim) evaluated the performance of several MPAs to select a test to be used in the main efficacy trial based on economic analysis, and assessed the feasibility and acceptability of a large UK trial. OPTIMA prelim used Oncotype DX as the primary discriminator; the main trial will use Prosigna (PAM50) with Prosigna Score ≤60 defined as “low-risk”. The co-primary outcomes are (1) Invasive Disease Free Survival (IDFS) and (2) cost-effectiveness of test-directed therapy. Secondary outcomes include IDFS in “low-risk” patients, quality of life and additional survival measures. An integrated qualitative recruitment study will identify and address challenges to recruitment and informed consent. Tumor blocks from all consenting participants will be banked allowing the performance of alternative MPA technologies to be evaluated. Recruitment of 4500 patients will permit demonstration of 3% non-inferiority of test-directed treatment, with 5% significance and 85% power, assuming 3 years follow-up and a control arm 5-year IDFS of at least 85%. The addition of patients from OPTIMA prelim will allow non-inferiority to be assessed with 2.5% significance.

Results: OPTIMA-prelim recruited 412 patients in 23 months from 35 sites with a 47% acceptance rate. The main study opened in January 2017. Early progress indicates that the recruitment target is achievable in the intended 46-month timescale through the participation of &gt;100 sites

Conclusion: OPTIMA, as one of two large scale prospective trials validating the use of test-guided chemotherapy decisions in node-positive early breast cancer, is expected to have a global impact on breast cancer treatment. Experience from OPTIMA prelim showed that patient advocate support and close engagement with sites will aid trial success.

Funding: The project is funded in the UK by the NIHR HTA Programme (10/34/501). Views expressed are those of the authors and not those of the HTA Programme, NIHR, NHS or the DoH.

Citation Format: Stein RC, Makris A, Hughes-Davies L, Macpherson IR, Hall PS, Cameron DA, Earl HM, Pinder SE, Poole CJ, Rea DW, McIntosh S, Harmer V, Morgan A, Rooshenas L, Conefrey C, Donovan JL, Hulme C, McCabe C, Stallard N, Campbell A, Higgins H, Bartlett JMS, Marshall A, Dunn JA. OPTIMA: A prospective randomized trial to validate the predictive utility and cost-effectiveness of gene expression test-directed chemotherapy decisions in early breast cancer [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 OT1-06-01.

Development of a framework to improve the process of recruitment to randomised controlled trials (RCTs): the SEAR (Screened, Eligible, Approached, Randomised) framework

BACKGROUND

Research has shown that recruitment to trials is a process that stretches from identifying potentially eligible patients, through eligibility assessment, to obtaining informed consent. The length and complexity of this pathway means that many patients do not have the opportunity to consider participation. This article presents the development of a simple framework to document, understand and improve the process of trial recruitment.

METHODS

Eight RCTs integrated a QuinteT Recruitment Intervention (QRI) into the main trial, feasibility or pilot study. Part of the QRI required mapping the patient recruitment pathway using trial-specific screening and recruitment logs. A content analysis compared the logs to identify aspects of the recruitment pathway and process that were useful in monitoring and improving recruitment. Findings were synthesised to develop an optimised simple framework that can be used in a wide range of RCTs.

RESULTS

The eight trials recorded basic information about patients screened for trial participation and randomisation outcome. Three trials systematically recorded reasons why an individual was not enrolled in the trial, and further details why they were not eligible or approached, or declined randomisation. A framework to facilitate clearer recording of the recruitment process and reasons for non-participation was developed: SEAR - Screening, to identify potentially eligible trial participants; Eligibility, assessed against the trial protocol inclusion/exclusion criteria; Approach, the provision of oral and written information and invitation to participate in the trial, and Randomised or not, with the outcome of randomisation or treatment received.

CONCLUSIONS

The SEAR framework encourages the collection of information to identify recruitment obstacles and facilitate improvements to the recruitment process. SEAR can be adapted to monitor recruitment to most RCTs, but is likely to add most value in trials where recruitment problems are anticipated or evident. Further work to test it more widely is recommended.

Value of Information Analysis of Multiparameter Tests for Chemotherapy in Early Breast Cancer: The OPTIMA Prelim Trial

BACKGROUND

Precision medicine is heralded as offering more effective treatments to smaller targeted patient populations. In breast cancer, adjuvant chemotherapy is standard for patients considered as high-risk after surgery. Molecular tests may identify patients who can safely avoid chemotherapy.

OBJECTIVES

To use economic analysis before a large-scale clinical trial of molecular testing to confirm the value of the trial and help prioritize between candidate tests as randomized comparators.

METHODS

Women with surgically treated breast cancer (estrogen receptor-positive and lymph node-positive or tumor size ≥30 mm) were randomized to standard care (chemotherapy for all) or test-directed care using Oncotype DX™. Additional testing was undertaken using alternative tests: MammaPrint^TM, PAM-50 (Prosigna^TM), MammaTyper^TM, IHC4, and IHC4-AQUA™ (NexCourse Breast™). A probabilistic decision model assessed the cost-effectiveness of all tests from a UK perspective. Value of information analysis determined the most efficient publicly funded ongoing trial design in the United Kingdom.

RESULTS

There was an 86% probability of molecular testing being cost-effective, with most tests producing cost savings (range -£1892 to £195) and quality-adjusted life-year gains (range 0.17-0.20). There were only small differences in costs and quality-adjusted life-years between tests. Uncertainty was driven by long-term outcomes. Value of information demonstrated value of further research into all tests, with Prosigna currently being the highest priority for further research.

CONCLUSIONS

Molecular tests are likely to be cost-effective, but an optimal test is yet to be identified. Health economics modeling to inform the design of a randomized controlled trial looking at diagnostic technology has been demonstrated to be feasible as a method for improving research efficiency.

Accelerated versus standard epirubicin followed by cyclophosphamide, methotrexate, and fluorouracil or capecitabine as adjuvant therapy for breast cancer in the randomised UK TACT2 trial (CRUK/05/19): a multicentre, phase 3, open-label, randomised, controlled trial

BACKGROUND

Adjuvant chemotherapy for early breast cancer has improved outcomes but causes toxicity. The UK TACT2 trial used a 2×2 factorial design to test two hypotheses: whether use of accelerated epirubicin would improve time to tumour recurrence (TTR); and whether use of oral capecitabine instead of cyclophosphamide would be non-inferior in terms of patients' outcomes and would improve toxicity, quality of life, or both.

METHODS

In this multicentre, phase 3, randomised, controlled trial, we enrolled patients aged 18 years or older from 129 UK centres who had histologically confirmed node-positive or high-risk node-negative operable breast cancer, had undergone complete excision, and were due to receive adjuvant chemotherapy. Patients were randomly assigned to receive four cycles of 100 mg/m2 epirubicin either every 3 weeks (standard epirubicin) or every 2 weeks with 6 mg pegfilgrastim on day 2 of each cycle (accelerated epirubicin), followed by four 4-week cycles of either classic cyclophosphamide, methotrexate, and fluorouracil (CMF; 600 mg/m2 cyclophosphamide intravenously on days 1 and 8 or 100 mg/m2 orally on days 1-14; 40 mg/m2 methotrexate intravenously on days 1 and 8; and 600 mg/m2 fluorouracil intravenously on days 1 and 8 of each cycle) or four 3-week cycles of 2500 mg/m2 capecitabine (1250 mg/m2 given twice daily on days 1-14 of each cycle). The randomisation schedule was computer generated in random permuted blocks, stratified by centre, number of nodes involved (none vs one to three vs four or more), age (≤50 years vs >50 years), and planned endocrine treatment (yes vs no). The primary endpoint was TTR, defined as time from randomisation to first invasive relapse or breast cancer death, with intention-to-treat analysis of standard versus accelerated epirubicin and per-protocol analysis of CMF versus capecitabine. This trial is registered with ISRCTN, number 68068041, and with ClinicalTrials.gov, number NCT00301925.

FINDINGS

From Dec 16, 2005, to Dec 5, 2008, 4391 patients (4371 women and 20 men) were recruited. At a median follow-up of 85·6 months (IQR 80·6-95·9) no significant difference was seen in the proportions of patients free from TTR events between the accelerated and standard epirubicin groups (overall hazard ratio [HR] 0·94, 95% CI 0·81-1·09; stratified p=0·42). At 5 years, 85·9% (95% CI 84·3-87·3) of patients receiving standard epirubicin and 87·1% (85·6-88·4) of those receiving accelerated epirubicin were free from TTR events. 4358 patients were included in the per-protocol analysis, and no difference was seen in the proportions of patients free from TTR events between the CMF and capecitabine groups (HR 0·98, 95% CI 0·85-1.14; stratified p=0·00092 for non-inferiority). Compared with baseline, significantly more patients taking CMF than those taking capecitabine had clinically relevant worsening of quality of life at end of treatment (255 [58%] of 441 vs 235 [50%] of 475; p=0·011) and at 12 months (114 [34%] of 334 vs 89 [22%] of 401; p<0·001 at 12 months) and had worse quality of life over time (p<0·0001). Detailed toxicity and quality-of-life data were collected from 2115 (48%) of treated patients. The most common grade 3 or higher adverse events in cycles 1-4 were neutropenia (175 [16%]) and fatigue (56 [5%]) of the 1070 patients treated with standard epirubicin, and fatigue (63 [6%]) and infection (34 [3%]) of the 1045 patients treated with accelerated epirubicin. In cycles 5-8, the most common grade 3 or higher adverse events were neutropenia (321 [31%]) and fatigue (109 [11%]) in the patients treated with CMF, and hand-foot syndrome (129 [12%]) and diarrhoea (67 [6%]) in the 1044 patients treated with capcitabine.

INTERPRETATION

We found no benefit from increasing the dose density of the anthracycline component of chemotherapy. However, capecitabine could be used in place of CMF without significant loss of efficacy and with improved quality of life.

FUNDING

Cancer Research UK, Amgen, Pfizer, and Roche.

Discrepancies in central review re-testing of patients with ER-positive and HER2-negative breast cancer in the OPTIMA prelim randomised clinical trial

Background:

There is limited data on results of central re-testing of samples from patients with invasive breast cancer categorised in their local hospital laboratories as oestrogen receptor (ER) positive and human epidermal growth factor receptor homologue 2 (HER2) negative.

Methods:

The Optimal Personalised Treatment of early breast cancer usIng Multiparameter Analysis preliminary study (OPTIMA prelim) was the feasibility phase of a randomised controlled trial to validate the use of multiparameter assay-directed chemotherapy decisions in the UK National Health Service (NHS). Eligibility criteria included ER positivity and HER2 negativity. Central re-testing of receptor status was mandatory.

Results:

Of the 431 patients tested centrally, discrepant results between central and local laboratory results were identified in only 19 (4.4% 95% confidence interval 2.5–6.3%) patients (with 21 tumours). On central review, seven patients had cancers that were ER-negative (1.6%) and 13 (3.0%) patients with 15 tumours had HER2-positive disease, including one tumour discrepant for both biomarkers.

Conclusions:

Central re-testing of receptor status of invasive breast cancers in the UK NHS setting shows a high level of reproducibility in categorising tumours as ER-positive and HER2-negative, and raises questions regarding the cost effectiveness and clinical value of central re-testing in this sub-group of breast cancers in this setting.

OPTIMA prelim: a randomised feasibility study of personalised care in the treatment of women with early breast cancer

BACKGROUND

There is uncertainty about the chemotherapy sensitivity of some oestrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-negative breast cancers. Multiparameter assays that measure the expression of several tumour genes simultaneously have been developed to guide the use of adjuvant chemotherapy for this breast cancer subtype. The assays provide prognostic information and have been claimed to predict chemotherapy sensitivity. There is a dearth of prospective validation studies. The Optimal Personalised Treatment of early breast cancer usIng Multiparameter Analysis preliminary study (OPTIMA prelim) is the feasibility phase of a randomised controlled trial (RCT) designed to validate the use of multiparameter assay directed chemotherapy decisions in the NHS.

OBJECTIVES

OPTIMA prelim was designed to establish the acceptability to patients and clinicians of randomisation to test-driven treatment assignment compared with usual care and to select an assay for study in the main RCT.

DESIGN

Partially blinded RCT with adaptive design.

SETTING

Thirty-five UK hospitals.

PARTICIPANTS

Patients aged ≥ 40 years with surgically treated ER-positive HER2-negative primary breast cancer and with 1-9 involved axillary nodes, or, if node negative, a tumour at least 30 mm in diameter.

INTERVENTIONS

Randomisation between two treatment options. Option 1 was standard care consisting of chemotherapy followed by endocrine therapy. In option 2, an Oncotype DX(®) test (Genomic Health Inc., Redwood City, CA, USA) performed on the resected tumour was used to assign patients either to standard care [if 'recurrence score' (RS) was > 25] or to endocrine therapy alone (if RS was ≤ 25). Patients allocated chemotherapy were blind to their randomisation.

MAIN OUTCOME MEASURES

The pre-specified success criteria were recruitment of 300 patients in no longer than 2 years and, for the final 150 patients, (1) an acceptance rate of at least 40%; (2) recruitment taking no longer than 6 months; and (3) chemotherapy starting within 6 weeks of consent in at least 85% of patients.

RESULTS

Between September 2012 and 3 June 2014, 350 patients consented to join OPTIMA prelim and 313 were randomised; the final 150 patients were recruited in 6 months, of whom 92% assigned chemotherapy started treatment within 6 weeks. The acceptance rate for the 750 patients invited to participate was 47%. Twelve out of the 325 patients with data (3.7%, 95% confidence interval 1.7% to 5.8%) were deemed ineligible on central review of receptor status. Interviews with researchers and recordings of potential participant consultations made as part of the integral qualitative recruitment study provided insights into recruitment barriers and led to interventions designed to improve recruitment. Patient information was changed as the result of feedback from three patient focus groups. Additional multiparameter analysis was performed on 302 tumour samples. Although Oncotype DX, MammaPrint(®)/BluePrint(®) (Agendia Inc., Irvine, CA, USA), Prosigna(®) (NanoString Technologies Inc., Seattle, WA, USA), IHC4, IHC4 automated quantitative immunofluorescence (AQUA(®)) [NexCourse BreastTM (Genoptix Inc. Carlsbad, CA, USA)] and MammaTyper(®) (BioNTech Diagnostics GmbH, Mainz, Germany) categorised comparable numbers of tumours into low- or high-risk groups and/or equivalent molecular subtypes, there was only moderate agreement between tests at an individual tumour level (kappa ranges 0.33-0.60 and 0.39-0.55 for tests providing risks and subtypes, respectively). Health economics modelling showed the value of information to the NHS from further research into multiparameter testing is high irrespective of the test evaluated. Prosigna is currently the highest priority for further study.

CONCLUSIONS

OPTIMA prelim has achieved its aims of demonstrating that a large UK clinical trial of multiparameter assay-based selection of chemotherapy in hormone-sensitive early breast cancer is feasible. The economic analysis shows that a trial would be economically worthwhile for the NHS. Based on the outcome of the OPTIMA prelim, a large-scale RCT to evaluate the clinical effectiveness and cost-effectiveness of multiparameter assay-directed chemotherapy decisions in hormone-sensitive HER2-negative early breast would be appropriate to take place in the NHS.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN42400492.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 20, No. 10. See the NIHR Journals Library website for further project information. The Government of Ontario funded research at the Ontario Institute for Cancer Research. Robert C Stein received additional support from the NIHR University College London Hospitals Biomedical Research Centre.

Comparing Breast Cancer Multiparameter Tests in the OPTIMA Prelim Trial: No Test Is More Equal Than the Others

BACKGROUND

Previous reports identifying discordance between multiparameter tests at the individual patient level have been largely attributed to methodological shortcomings of multiple in silico studies. Comparisons between tests, when performed using actual diagnostic assays, have been predicted to demonstrate high degrees of concordance. OPTIMA prelim compared predicted risk stratification and subtype classification of different multiparameter tests performed directly on the same population.

METHODS

Three hundred thirteen women with early breast cancer were randomized to standard (chemotherapy and endocrine therapy) or test-directed (chemotherapy if Oncotype DX recurrence score >25) treatment. Risk stratification was also determined with Prosigna (PAM50), MammaPrint, MammaTyper, NexCourse Breast (IHC4-AQUA), and conventional IHC4 (IHC4). Subtype classification was provided by Blueprint, MammaTyper, and Prosigna.

RESULTS

Oncotype DX predicted a higher proportion of tumors as low risk (82.1%, 95% confidence interval [CI] = 77.8% to 86.4%) than were predicted low/intermediate risk using Prosigna (65.5%, 95% CI = 60.1% to 70.9%), IHC4 (72.0%, 95% CI = 66.5% to 77.5%), MammaPrint (61.4%, 95% CI = 55.9% to 66.9%), or NexCourse Breast (61.6%, 95% CI = 55.8% to 67.4%). Strikingly, the five tests showed only modest agreement when dichotomizing results between high vs low/intermediate risk. Only 119 (39.4%) tumors were classified uniformly as either low/intermediate risk or high risk, and 183 (60.6%) were assigned to different risk categories by different tests, although 94 (31.1%) showed agreement between four of five tests. All three subtype tests assigned 59.5% to 62.4% of tumors to luminal A subtype, but only 121 (40.1%) were classified as luminal A by all three tests and only 58 (19.2%) were uniformly assigned as nonluminal A. Discordant subtyping was observed in 123 (40.7%) tumors.

CONCLUSIONS

Existing evidence on the comparative prognostic information provided by different tests suggests that current multiparameter tests provide broadly equivalent risk information for the population of women with estrogen receptor (ER)-positive breast cancers. However, for the individual patient, tests may provide differing risk categorization and subtype information.

Abstract OT3-02-12: OPTIMA (optimal personalised treatment of early breast cancer usIng multi-parameter analysis), a prospective trial to validate the predictive utility and cost-effectiveness of gene expression test-directed chemotherapy decisions

Background: Multi-parameter gene expression assays (MPAs) are widely used to estimate individual patient residual risk and to guide chemotherapy use in hormone-sensitive HER2-negative node-negative early breast cancer. These uses of MPAs have not yet been prospectively validated. OPTIMA aims to validate the use of MPA testing to predict chemotherapy sensitivity in a largely node-positive breast cancer population.

Methods: OPTIMA is a partially blinded multi-center, phase 3 randomized controlled trial with an adaptive two-stage design. The preliminary phase (OPTIMA prelim) evaluated the performance of MPAs to identify a suitable test(s) to be used in the main efficacy trial and assessed the feasibility and acceptability of a large UK trial. Eligible patients are men or women aged 40 years or older who have surgically resected early stage breast cancer, which is ER-positive and HER2-negative and who have either 1-9 involved axillary lymph nodes or tumors of at least 30mm diameter. Randomization is to standard management (chemotherapy followed by endocrine therapy) or to MPA-directed treatment. Those with a tumor categorized as "high-risk" by the test will be assigned to standard management whilst those at "low-risk" will be treated with endocrine therapy alone. OPTIMA prelim used Oncotype DX as the primary discriminator; the main trial will use Prosigna (PAM50). The co-primary outcomes are (1) Invasive Disease Free Survival (IDFS) and (2) cost-effectiveness of test-directed therapy compared to standard practice. Secondary outcomes include IDFS in "low-risk" patients, distant disease free survival, breast cancer specific survival, overall survival and quality of life. An integrated qualitative recruitment study will identify and address challenges to recruitment and informed consent. Tumor blocks from all consenting participants will be banked allowing the performance of alternative MPA technologies to be evaluated. Recruitment of 4500 patients over 4 years will permit demonstration of 3% non-inferiority of test-directed treatment, with 5% significance and 85% power, assuming 3 years follow-up and a control arm 5-year IDFS of at least 85%. The addition of patients from OPTIMA prelim will allow non-inferiority to be assessed with 2.5% significance.

Results: OPTIMA-prelim recruited 412 patients in 23 months from 35 sites. It confirmed the acceptability of randomization to patients with a 47% acceptance rate, and to clinicians and hence the feasibility of a large prospective trial of test-directed treatment running in 100-plus UK sites. It showed that investment into research on test-directed therapy, especially with Prosigna, should be of substantial value to the NHS.

Conclusion: OPTIMA, as one of two large scale prospective trials validating the use of test-guided chemotherapy in node-positive hormone-sensitive early breast cancer will have a global impact on patient treatment. Recruitment into the main efficacy trial will commence in October 2015.

Funding: Project funded by the UK NIHR HTA Programme (10/34/501). Views expressed are those of the authors and not those of the HTA Programme, NIHR, NHS or the DoH.

Citation Format: Stein RC, Marshall A, Hall PS, Bartlett JMS, Rooshenas L, Campbell A, Cameron DA, Rea D, Macpherson I, Earl HM, Poole CJ, Francis A, Morgan A, Harmer V, Pinder SE, Stallard N, Donovan J, Hulme C, McCabe C, Hughes-Davies L, Makris A, Dunn JA. OPTIMA (optimal personalised treatment of early breast cancer usIng multi-parameter analysis), a prospective trial to validate the predictive utility and cost-effectiveness of gene expression test-directed chemotherapy decisions. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr OT3-02-12.

Abstract P6-08-11: UK OPTIMA-prelim study demonstrates economic value in more clinical evaluation of multi-parameter prognostic tests in early breast cancer

Background

There is uncertainty about the benefit of chemotherapy for some patients with ER-positive HER2-negative early breast cancer. Multi-parameter assays of gene expression may enhance the value of chemotherapy through personalised treatment decisions. An economic evaluation was undertaken in the context of the feasibility phase of an RCT (OPTIMA prelim) designed to validate prospectively the use of such an assay as a treatment decision tool in the UK National Health Service (NHS). The aim of the economic evaluation was to confirm value in an ongoing RCT and optimise its design for economic endpoints. Comparators included (i) All patients treated with chemotherapy, (ii) Oncotype DX, (iii) MammaPrint/BluePrint and (iv) Prosigna.

Methods

A model-based cost-effectiveness analysis was conducted to the standards of the UK National Institute for Care Excellence (NICE) reference case. A Markov model was constructed to simulate the care pathway of a cohort of patients with characteristics identified in the OPTIMA prelim study or, where unavailable, from the published literature. The costs (GBP) and benefits (QALYs) were estimated over a time horizon of the patient life-time. Alternative scenarios of recurrence rates and chemotherapy effect were explored in patients identified high or low risk by the tests and treated with and without chemotherapy. Scenarios included estimates based on the SWOG-8814 trial, the EBCTCG and outcomes forecasted using Adjuvant! Online. Uncertainty introduced by discrepancy in patient selection between tests was modelled using a Bayesian decision analytic framework. Probabilistic sensitivity analysis and value of information analysis was conducted using Monte Carlo simulation.

Results

There were 285 randomised patients. Multi-parameter analyses were performed on tumour samples and baseline factors were included in the model. The cost-effectiveness of all tests was uncertain. Uncertainty was predominantly driven by assumptions about long term recurrence rates in test-selected groups and the ability of tests to predict benefit from chemotherapy. The relationship between recurrence-free survival and life expectancy in test-selected groups and in patients who did or did not receive adjuvant chemotherapy was also important. The incremental cost-effectiveness ratio (ICER) for Oncotype DX compared with chemotherapy for all was cost-effective in many scenarios, ranging from GBP26,000 per QALY to resulting in increased QALYs with cost savings (dominate), depending on assumptions. The value of information analysis placed high societal value in further research into recurrence-free survival for test-directed chemotherapy, irrespective of the test evaluated.

Conclusion

There is substantial value in prospective comparative research into all tests evaluated, including long term outcomes, to resolve uncertainties in the clinical and economic optimal choice of test.

Acknowledgements

This project was funded by the National Institute for Health Research Health Technology Assessment (NIHR HTA) Programme (project number 10/34/01). The views and opinions expressed therein are those of the authors and do not necessarily reflect those of the HTA programme, NIHR, NHS or the Department of Health.

Citation Format: Peter S Hall, Alison F Smith, Armando Vargas-Palacios, Robert C Stein, John Bartlett, Jane Bayani, Andrea Marshall, Janet A Dunn, Amy F Campbell, Carrie Cunningham, Leila Rooshenas, Monika Sobol, Adrienne Morgan, Christopher Poole, Sarah E Pinder, David A Cameron, Nigel Stallard, Jenny Donovan, Luke Hugh-Davies, Helena Earl, Andreas Makris, Claire Hulme, Christopher McCabe. UK OPTIMA-prelim study demonstrates economic value in more clinical evaluation of multi-parameter prognostic tests in early breast cancer [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P6-08-11.

Macroscopic handling and reporting of breast cancer specimens pre- and post-neoadjuvant chemotherapy treatment: review of pathological issues and suggested approaches

Neoadjuvant chemotherapy (NACT) is used increasingly in the treatment of invasive breast cancer and presents challenges for the pathologist in the handling and interpretation of tissues. Potential issues include pathological identification and localization of the residual tumour site; how best to assess pathological response (given the diversity of scoring systems described); the timing and assessment of axillary node biopsy; and the value of retesting any residual tumour for dissonance between core biopsy and post-treatment residual cancer cells for biomarker expression such as oestrogen and progesterone receptors and human epidermal growth factor receptor 2 (HER2). The role of the pathologist is critical in modern NACT approaches to breast cancer and is likely to remain challenging as novel agents and newer biomarkers become available. In this manuscript we review these issues and describe some practical approaches to handling and reporting these samples in the routine histopathology laboratory.

Adaptive designs for clinical trials assessing biomarker-guided treatment strategies

BACKGROUND

The Biomarker Strategy Design has been proposed for trials assessing the value of a biomarker in guiding treatment in oncology. In such trials, patients are randomised to either receive the standard chemotherapy treatment or a biomarker-directed treatment arm, in which biomarker status is used to guide treatment.

METHODS

Motivated by a current trial, we consider an adaptive design in which two biomarkers are assessed. The trial is conducted in two stages. In the first stage, patients in the biomarker-guided arm are assessed using a standard and an alternative cheaper biomarker, with the standard biomarker guiding treatment. An analysis comparing biomarker results is then used to choose the biomarker to use for the remainder of the trial. The new biomarker is used if the results for the two biomarkers are sufficiently similar.

RESULTS

We show that in practical situations the first-stage results can be used to adapt the trial without type I error rate inflation. We also show that there can be considerable cost gains with only a small loss in power in the case where the alternative biomarker is highly concordant with the standard one.

CONCLUSIONS

Adaptive designs have an important role in reducing the cost and increasing the clinical utility of trials evaluating biomarker-guided treatment strategies.

Economic evaluation of genomic test-directed chemotherapy for early-stage lymph node-positive breast cancer

BACKGROUND

Multi-parameter genomic tests identify patients with early-stage breast cancer who are likely to derive little benefit from adjuvant chemotherapy. These tests can potentially spare patients the morbidity from unnecessary chemotherapy and reduce costs. However, the costs of the test must be balanced against the health benefits and cost savings produced. This economic evaluation compared genomic test-directed chemotherapy using the Oncotype DX 21-gene assay with chemotherapy for all eligible patients with lymph node-positive, estrogen receptor-positive early-stage breast cancer.

METHODS

We performed a cost-utility analysis using a state transition model to calculate expected costs and benefits over the lifetime of a cohort of women with estrogen receptor-positive lymph node-positive breast cancer from a UK perspective. Recurrence rates for Oncotype DX-selected risk groups were derived from parametric survival models fitted to data from the Southwest Oncology Group 8814 trial. The primary outcome was the incremental cost-effectiveness ratio, expressed as the cost (in 2011 GBP) per quality-adjusted life-year (QALY). Confidence in the incremental cost-effectiveness ratio was expressed as a probability of cost-effectiveness and was calculated using Monte Carlo simulation. Model parameters were varied deterministically and probabilistically in sensitivity analysis. Value of information analysis was used to rank priorities for further research.

RESULTS

The incremental cost-effectiveness ratio for Oncotype DX-directed chemotherapy using a recurrence score cutoff of 18 was £5529 (US $8852) per QALY. The probability that test-directed chemotherapy is cost-effective was 0.61 at a willingness-to-pay threshold of £30 000 per QALY. Results were sensitive to the recurrence rate, long-term anthracycline-related cardiac toxicity, quality of life, test cost, and the time horizon. The highest priority for further research identified by value of information analysis is the recurrence rate in test-selected subgroups.

CONCLUSIONS

There is substantial uncertainty regarding the cost-effectiveness of Oncotype DX-directed chemotherapy. It is particularly important that future research studies to inform cost-effectiveness-based decisions collect long-term outcome data.

Trastuzumab beyond progression: overall survival analysis of the GBG 26/BIG 3-05 phase III study in HER2-positive breast cancer

BACKGROUND

Continuation of trastuzumab plus capecitabine (XH) showed a significantly improved overall response rate and time to progression compared with capecitabine (X) alone in women with HER2-positive breast cancer progressing during trastuzumab treatment. Here, we report the final analysis on overall survival.

PATIENTS AND METHODS

Patients with HER2-positive, advanced breast cancer who progressed during treatment with trastuzumab with or without 1st-line metastatic chemotherapy were prospectively randomised to X (2500mg/m(2) on days 1-14, q3w) or XH (6 (8)mg/kg, q3w). Overall survival was a pre-specified secondary end-point.

RESULTS

Median follow-up at June 2010 was 20.7months. Fifty nine of 74 and 60 of 77 patients died in the X and XH arm, respectively. Median overall survival was 20.6 and 24.9months with X and XH, respectively (HR=0.94 [0.65-1.35]; p=0.73). Performance status and metastatic site were independent prognosticators for overall survival. No difference between treatment arms was observed for patients who achieved clinical response or clinical benefit, respectively. Patients who continued/restarted anti-HER2 treatment (trastuzumab or lapatinib) after 2nd progression (N=52) had a post-progression survival of 18.8 compared with 13.3months for those who did not receive 3rd line treatment with anti-HER2 agents (N=88) (HR 0.63; p=0.02).

CONCLUSIONS

Final overall survival analysis of the GBG-26 study did not demonstrate a significant survival benefit for treatment beyond progression with trastuzumab. However, in a post-hoc analysis, patients receiving anti-HER2 treatment as 3rd line therapy showed a better post-progression survival than those not receiving this targeted treatment.

Trastuzumab beyond progression in human epidermal growth factor receptor 2-positive advanced breast cancer: a german breast group 26/breast international group 03-05 study

PURPOSE

Trastuzumab shows clinical activity in human epidermal growth factor receptor 2 (HER-2)-positive early and advanced breast cancer. In the German Breast Group 26/Breast International Group 03-05 trial, we investigated if trastuzumab treatment should be continued beyond progression.

METHODS

Patients with HER-2-positive breast cancer that progresses during treatment with trastuzumab were randomly assigned to receive capecitabine (2,500 mg/m(2) body-surface area on days 1 through 14 [1,250 mg/m(2) semi-daily]) alone or with continuation of trastuzumab (6 mg/kg body weight) in 3-week cycles. The primary end point was time to progression.

RESULTS

We randomly assigned 78 patients to capecitabine and 78 patients to capecitabine plus trastuzumab. Sixty-five events and 38 deaths in the capecitabine group and 62 events and 33 deaths in the capecitabine-plus-trastuzumab group occurred during 15.6 months of follow-up. Median times to progression were 5.6 months in the capecitabine group and 8.2 months in the capecitabine-plus-trastuzumab group with an unadjusted hazard ratio of 0.69 (95% CI, 0.48 to 0.97; two-sided log-rank P = .0338). Overall survival rates were 20.4 months (95% CI, 17.8 to 24.7) in the capecitabine group and 25.5 months (95% CI, 19.0 to 30.7) in the capecitabine-plus-trastuzumab group (P = .257). Overall response rates were 27.0% with capecitabine and 48.1% with capecitabine plus trastuzumab (odds ratio, 2.50; P = .0115). Continuation of trastuzumab beyond progression was not associated with increased toxicity.

CONCLUSION

Continuation of trastuzumab plus capecitabine showed a significant improvement in overall response and time to progression compared with capecitabine alone in women with HER-2-positive breast cancer who experienced progression during trastuzumab treatment.

Predictors of ovarian reserve in young women with breast cancer

Ovarian reserve can be diminished following treatment for breast cancer. This study evaluated biochemical and biophysical parameters of ovarian reserve in these patients. Biochemical and biophysical tests of ovarian reserve were performed simultaneously in young (age 22–42 years), regularly menstruating women with breast cancer (n=22) and age-matched controls (n=24). All tests were performed before (baseline) and after transient ovarian stimulation in the early follicular phase. Patients were recruited both before and after completion of chemotherapy, with some patients being followed up prospectively. Serum samples were analysed for follicle-stimulating hormone (FSH), luteinising hormone (LH), oestradiol (E₂), inhibins A and B, and antimullerian hormone (AMH). Biophysical (ultrasound) tests included ovarian volume, antral follicle count (AFC), ovarian stromal blood flow and uterine dimensions. Significant differences were revealed (when compared with the controls) for basal FSH (11.32±1.48 vs 6.62±0.42 mIU ml⁻¹, P<0.001), basal AMH (0.95±0.34 vs 7.89±1.62 ng ml⁻¹, P<0.001) and basal inhibin B (19.24±4.56 vs 83.61±13.45 pg ml⁻¹, P<0.001). Following transient ovarian stimulation, there were significant differences in the increment change (Δ) for inhibin B (3.02±2.3 vs 96.82±16.38 pg ml⁻¹, P<0.001) and E₂ (107.8±23.95 vs 283.2±40.34 pg ml⁻¹, P<0.01). AFC was the only biophysical parameter that was significantly different between patients and the controls (7.80±0.85 vs 16.77±1.11, P<0.001). Basal and stimulated biochemical (serum AMH, FSH, inhibin B and E₂) and biophysical (AFC) tests may be potential markers of ovarian reserve in young women with breast cancer.

Insulin induces phosphatidylinositol-3-phosphate formation through TC10 activation

Phosphatidylinositol-3-phosphate (PtdIns-3-P) is considered as a lipid constitutively present on endosomes; it does not seem to have a dynamic role in signalling. In contrast, phosphatidylinositol-3,4,5-trisphosphate (PtdIns-3,4,5-P(3)) plays a crucial role in different signalling pathways including translocation of the glucose transporter protein GLUT4 to the plasma membrane upon insulin receptor activation. GLUT4 translocation requires activation of two distinct pathways involving phosphatidylinositol 3-kinase (PI 3-K) and the small GTP-binding protein TC10, respectively. The contribution of each pathway remains to be elucidated. Here we show that insulin specifically induces the formation of PtdIns-3-P in insulin- responsive cells. The insulin-mediated formation of PtdIns-3-P occurs through the activation of TC10 at the lipid rafts subdomain of the plasma membrane. Exogenous PtdIns-3-P induces the plasma membrane translocation of both overexpressed and endogenous GLUT4. These data indicate that PtdIns-3-P is specifically produced downstream from insulin-mediated activation of TC10 to promote the plasma membrane translocation of GLUT4. These results give a new insight into the intracellular role of PtdIns-3-P and shed light on some aspects of insulin signalling so far not completely understood.

The application of 2D gel-based proteomics methods to the study of breast cancer

The protein complement of breast cells consists of many thousands of proteins. Recent developments in 2D gel electrophoresis technology have made studies requiring the quantitative analysis of a differential proteome, such as comparison between normal and malignant cells or investigation of drug effects on cells, truly feasible. Computer software plays a central part in the comparisons between multiple gels required for such experiments. In addition, software tools allow patterns of coexpression of proteins to be studied, offering potential insights into protein regulation, interactions, and functions, especially when combined with complementary data on gene expression. In this paper, the technology and limitations of 2D gel-based proteomics are reviewed. Techniques for comparing sets of gels at a global level as well as identifying specific protein features that differentiate gels are discussed. Our own experience of studying the breast cell proteome is used to illustrate the difficulties and achievements of differential proteomics.

Cluster analysis of an extensive human breast cancer cell line protein expression map database

In the current study, the protein expression maps (PEMs) of 26 breast cancer cell lines and three cell lines derived from normal breast or benign disease tissue were visualised by high resolution two-dimensional gel electrophoresis. Analysis of this data was performed with ChiClust and ChiMap, two analytical bioinformatics tools that are described here. These tools are designed to facilitate recognition of specific patterns shared by two or more (a series) PEMs. Both tools use PEMs that were matched by an image analysis program and locally written programs to create a match table that is saved in an object relational database. The ChiClust tool uses clustering and subclustering methods to extract statistically significant protein expression patterns from a large series of PEMs. The ChiMap tool calculates a differential value (either as percentage change or a fold change) and represents these graphically. All such differentials or just those identified using ChiClust can be submitted to ChiMap. These methods are not dependent on any particular commercial image analysis program, and the whole software package gives an integrated procedure for the comparison and analysis of a series of PEMs. The ChiClust tool was used here to order the breast cell lines into groups according to biological characteristics including morphology in vitro and tumour forming ability in vivo. ChiMap was then used to highlight eight major protein feature-changes detected between breast cancer cell lines that either do or do not proliferate in nude mice. Mass spectrometry was used to identify the proteins. The possible role of these proteins in cancer is discussed.

Prospects for phosphoinositide 3-kinase inhibition as a cancer treatment

The phosphoinositide 3-kinases (PI3-kinases) are a family of lipid kinases that have a key role in the regulation of many cellular processes including proliferation, survival, carbohydrate metabolism, and motility. There is now strong evidence that some members of the PI3-kinase family have an important role in cancer. Emerging evidence for functional specialisation of PI3-kinase isoforms suggests that isoform selective inhibitors, in contrast to the existing non-selective inhibitors wortmannin and LY294002, may prove to be useful anticancer drugs.

The toxicology of Myrmecia nigrocincta, an Australian ant

The biology, behaviour and venom of the ant Myrmecia nigrocincta are described. Symptoms of 15 cases of envenomation are described.

PI3-kinase inhibition: a target for drug development?

The phosphoinositide 3-kinases (PI3-kinases) are a ubiquitously expressed enzyme family that, through the generation of phospholipid second messengers, play a key role in the regulation of many cellular processes. These include motility, proliferation and survival, and carbohydrate metabolism. Members of the PI3-kinase family and related kinases, their mechanism of activation and the cellular events that they influence are described in this review. As knowledge of their involvement in disease processes increases, the PI3-kinases appear to be an increasingly attractive target for drug development, particularly in the fields of cancer and other proliferative diseases, and in the treatment of inflammatory and immunological conditions. Evidence of the functional specialization of PI3-kinase isoforms suggests that selective inhibition with acceptable toxicity might be possible.

Phosphatidylinositol 3-kinase, protein kinase B and ribosomal S6 kinases in the stimulation of thyroid epithelial cell proliferation by cAMP and growth factors in the presence of insulin

The proliferation of most normal cells depends on the co-operation of several growth factors and hormones, each with a specific role, but the key events involved in the action of each necessary stimulant remain largely uncharacterized. In the present study, the pathways involved in the mechanism(s) of co-operation have been investigated in primary cultures of dog thyroid epithelial cells. In this physiologically relevant system, thyroid stimulating hormone (TSH) acting through cAMP, epidermal growth factor (EGF) and phorbol esters (such as PMA) induce DNA synthesis. Their effect requires stimulation of the insulin-like growth factor-1 (IGF-1) receptor by either IGF-1 or insulin, which are not themselves mitogenic agents. In contrast, hepatocyte growth factor (HGF) is itself fully mitogenic. The results of the study demonstrate that cAMP, EGF, HGF and PMA stimulate p70 ribosomal S6 kinase (p70 S6 kinase). However, insulin/IGF-1 also stimulate p70 S6 kinase. Thus stimulation of p70 S6 kinase might be necessary, but is certainly not sufficient, for the induction of DNA synthesis and is not specific for any stimulated pathway. In contrast, phosphatidylinositol 3-kinase (PI 3-kinase) and protein kinase B (PKB) activation by insulin and HGF is strong and sustained, whereas it is weak and transient with EGF and absent in the presence of TSH or PMA. These findings suggest that: (i) stimulation of PI 3-kinases and/or PKB is not involved in the cAMP-dependent pathways leading to thyrocyte proliferation, or in the action of PMA, (ii) the stimulation of the PI 3-kinase/PKB pathway may account for the permissive action of insulin/IGF-1 in the proliferation of these cells, and (iii) the stimulation of this pathway by HGF may explain why this agent does not require insulin or IGF-1 for its mitogenic action.

Proteomic definition of normal human luminal and myoepithelial breast cells purified from reduction mammoplasties

Normal human luminal and myoepithelial breast cells separately purified from a set of 10 reduction mammoplasties by using a double antibody magnetic affinity cell sorting and Dynabead immunomagnetic technique were used in two-dimensional gel proteome studies. A total of 43,302 proteins were detected across the 20 samples, and a master image for each cell type comprising a total of 1,738 unique proteins was derived. Differential analysis identified 170 proteins that were elevated 2-fold or more between the two breast cell types, and 51 of these were annotated by tandem mass spectrometry. Muscle-specific enzyme isoforms and contractile intermediate filaments including tropomyosin and smooth muscle (SM22) alpha protein were detected in the myoepithelial cells, and a large number of cytokeratin subclasses and isoforms characteristic of luminal cells were detected in this cell type. A further 134 nondifferentially regulated proteins were also annotated from the two breast cell types, making this the most extensive study to date of the protein expression map of the normal human breast and the basis for future studies of purified breast cancer cells.

Iodine-131-MIBG therapy of a patient with carcinoid liver metastases

Iodine-13I-metaiodobenzylguanidine (MIBG) is highly concentrated by >60% of carcinoid metastases and thus provides a therapeutic opportunity.

METHODS

A symptomatic patient with carcinoid liver metastases, unresponsive to chemotherapy combined with interferon-alpha, was subsequently treated with 131I-MIBG.

RESULTS

Radionuclide therapy, which was without significant side effects, resulted in symptomatic improvement and reduced urinary 5-hydroxyindoleacetic acid levels. No new metastases were observed for 15 mo after 131I-MIBG therapy. Gross cystic change occurred in existing liver metastases, presumably as a result of ischemic necrosis. Surgical deroofing and aspiration of cysts led to regeneration of normal liver tissue.

CONCLUSION

Iodine-131-MIBG therapy can provide prolonged symptomatic relief and improved quality of life in patients with metastatic carcinoid disease unresponsive to other therapies. The antitumor effect of 131I-MIBG was accompanied by few side effects, suggesting that this therapy should be considered in symptomatic patients with an early stage of disease.

Solution structure of the C-terminal SH2 domain of the p85 alpha regulatory subunit of phosphoinositide 3-kinase

Heterodimeric class IA phosphoinositide 3-kinase (PI 3-kinase) plays a crucial role in a variety of cellular signalling events downstream of a number of cell-surface receptor tyrosine kinases. Activation of the enzyme is effected in part by the binding of two Src homology-2 domains (SH2) of the 85 kDa regulatory subunit to specific phosphotyrosine-containing peptide motifs within activated cytoplasmic receptor domains. The solution structure of the uncomplexed C-terminal SH2 (C-SH2) domain of the p85 alpha subunit of PI 3-kinase has been determined by means of multinuclear, double and triple-resonance NMR experiments and restrained molecular-dynamics simulated-annealing calculations. The solution structure clearly indicates that the uncomplexed C-SH2 domain conforms to the consensus polypeptide fold exhibited by other SH2 domains, with an additional short helical element at the N terminus. In particular, the C-SH2 structure is very similar to both the p85 alpha N-terminal SH2 domain (N-SH2) and the Src SH2 domain with a root mean square difference (rmsd) for 44 C alpha atoms of 1.09 and 0.89 A, respectively. The canonical BC, EF and BG loops are less well-defined by the experimental restraints and show greater variability in the ensemble of C-SH2 conformers. The lower level of definition in these regions may reflect the presence of conformational disorder, an interpretation supported by the absence or broadening of backbone and side-chain NMR resonances for some of these residues. NMR experiments were performed, where C-SH2 was titrated with phosphotyrosine-containing peptides corresponding to p85 alpha recognition sites in the cytoplasmic domain of the platelet-derived growth-factor receptor. The ligand-induced chemical-shift perturbations indicate the amino-acid residues in C-SH2 involved in peptide recognition follow the pattern predicted from homologous complexes. A series of C-SH2 mutants was generated and tested for phosphotyrosine peptide binding by surface plasmon resonance. Mutation of the invariant Arg36 (beta B5) to Met completely abolishes phosphopeptide binding. Mutation of each of Ser38, Ser39 or Lys40 in the BC loop to Ala reduces the affinity of C-SH2 for a cognate phosphopeptide, as does mutation of His93 (BG5) to Asn. These effects are consistent with the involvement of the BC loop and BG loops regions in ligation of phosphopeptide ligands. Mutation of Cys57 (beta D5) in C-SH2 to Ile, the corresponding residue type in the p85 alpha N-SH2 domain, results in a change in peptide binding selectivity of C-SH2 towards that demonstrated by p85 alpha N-SH2. This pattern of p85 alpha phosphopeptide binding specificity is interpreted in terms of a model of the p85 alpha/PDGF-receptor interaction.

Cloning of a human phosphoinositide 3-kinase with a C2 domain that displays reduced sensitivity to the inhibitor wortmannin

The generation of phosphatidylinositide 3-phosphates has been observed in a variety of cellular responses. The enzymes that mediate synthesis are the phosphoinositide 3-kinases (PI3-Ks) that form a family of structurally diverse enzymes with distinct substrate specificities. In this paper, we describe the cloning of a novel human PI3-K, namely PI3-K-C2 alpha, which contains a C-terminal C2 domain. This enzyme can be assigned to the class II PI3-Ks, which was defined by characterization of the Drosophila 68D enzyme and includes the recently described murine enzymes m-cpk and p170. Despite the overall similarity in the amino acid sequence of the murine and human enzymes, which suggests that they are encoded by closely related genes, these molecules show marked sequence heterogeneity at their N-termini. Biochemical analysis of recombinant PI3-K-C2 alpha demonstrates a restricted lipid substrate specificity. As reported for other members of this class, the enzyme only phosphorylates PtdIns and PtdIns4P when the lipids are presented alone. However, when lipids were presented together with phosphatidylserine acting as a carrier, phosphorylation of PtdIns(4,5)P2 was also observed. The catalytic activity of PI3-K-C2 alpha is refractory to concentrations of wortmannin and LY294002 which inhibit the PI3-K activity of other family members. The comparative insensitivity of PI3-K-C2 alpha to these inhibitors suggests that their use should be reevaluated in the study of PI3-Ks.

A randomised prospective trial of surgical against medical tetracycline pleurodesis in the management of malignant pleural effusions secondary to breast cancer

Malignant pleural effusion is a frequent complication of metastatic breast cancer leading to a significant degree of morbidity. Drainage of the effusion by thoracocentesis and pleurodesis with tetracycline as the sclerosing agent is an established means of symptomatic relief in these patients. To determine whether the efficacy of tetracycline pleurodesis is improved by surgical rather than medical drainage and instillation of sclerosant, 34 patients were prospectively randomised to a trial comparing the two treatment modalities, of whom 29 were evaluable for response. The total failure rate of primary pleurodesis was 13.4%, the rate of recurrence of effusion within the first month was 24%, and only 1 patient (3.4%) required repeat aspiration in that time period. There was no significant difference in the rate of recurrence or reaspiration of effusion between the two treatment groups. Although the overall survival time from treatment of effusion is significantly longer in the surgical treatment group than in the medical treatment group (P = 0.03), this is likely to be due to factors other than the method of treating the effusion. We conclude that surgical tetracycline pleurodesis has no advantage over medical tetracycline pleurodesis.

Aromatization inhibition alone or in combination with GnRH agonists for the treatment of premenopausal breast cancer patients

Aromatase inhibition in postmenopausal women causes a marked fall in the plasma levels of oestrogens and is an effective treatment for breast cancer, however, trials with aminoglutethimide found that this aromatase inhibitor was ineffective in suppressing plasma oestrogen levels in premenopausal breast cancer patients. We found that the more potent inhibitor, 4-hydroxyandrostenedione (4-OHA), which can suppress oestrogen synthesis in rodents and non-human primates with intact ovarian function, was also unsuccessful as an oestrogen suppressant in premenopausal women at its maximum tolerated dose (500 mg/week i.m.). GnRH agonists are effective suppressants of ovarian oestrogen synthesis but oestrogen production from peripheral sites is unaffected. Our studies of a combination of the GnRH agonist goserelin and 4-OHA demonstrated that the combination caused greater oestrogen suppression than goserelin alone and led to objective clinical response in 4/6 breast cancer patients after their relapse from treatment with goserelin as a single agent. The combination of a GnRH agonist and an aromatase inhibitor should be subjected to clinical trials.

An endocrine and pharmacokinetic study of four oral doses of formestane in postmenopausal breast cancer patients

43 postmenopausal breast cancer patients were treated orally with the aromatase inhibitor formestane (4-hydroxyandrostenedione) at daily doses of 62.5, 125, 250 or 500 mg for 4 weeks followed by 250 mg daily for a further 4 weeks. For some patients, 62.5 mg did not suppress serum oestradiol levels maximally. The doses of 250 and 500 mg did not differ in their effectiveness. Oestrone levels were suppressed by all doses of formestane but no consistent changes of aldosterone, cortisol or 17-hydroxyprogesterone occurred. Serum levels of sex hormone binding globulin fell by about 15% during treatment with 250 mg formestane reflecting its minor androgenic activity. The maximum concentration and area under the curve of serum formestane levels after the first dose varied in an approximately linear manner with dose. It is concluded that formestane is an effective, specific suppressant of oestradiol levels via the oral route requiring no more than 250 mg to be given daily.

Lactic acidosis. A presentation of metastatic breast cancer arising in pregnancy

Lactic acidosis B is a rare metabolic complication of malignancy. It usually is associated with advanced and extensive metastatic disease. The authors report a case in which lactic acidosis was the presenting feature of a previously undiagnosed case of metastatic breast cancer in a pregnant woman and that resolved with successful antineoplastic treatment. The authors review the likely cause and management of the condition.

A preliminary clinical study of gossypol in advanced human cancer

A total of 34 patients with advanced cancer were given weekly or daily escalating doses of oral gossypol, a cottonseed-oil constituent showing evidence of antineoplastic activity in pre-clinical studies. No major adverse events occurred and there was no evidence of haematological or biochemical disturbance. As determined by dose escalation in 17 patients, the dose-limiting toxicity was emesis in 16 patients. There was no evidence of tumour regression in any of the 20 patients assessed for response. We conclude that gossypol is safe but unlikely to be clinically useful in patients with advanced cancer.

Mitozantrone and methotrexate chemotherapy with and without mitomycin C in the treatment of advanced breast cancer: a randomised clinical trial

Patients with advanced breast cancer were randomised to 3M (mitozantrone 6.5 mg/m2q 21 days, methotrexate 30 mg/m2q 21 days, mitomycin C 6.5 mg/m2q 42 days) or 2M (as 3M but without mitomycin C). The objective response rates of 30% in 51 evaluable patients receiving 3M and 26% of 54 patients receiving 2M were not significantly different. 4/16 patients not responding to 2M responded to 3M on crossover. Both regimes were well tolerated but there was significantly less haematological toxicity and fewer dose reductions and delays with 2M. We conclude that patients should initially be treated with 2M and that non-responding patients should be crossed to 3M.

Clinical oncology: case presentations from oncology centres. 1. Ewing's sarcoma. The London Bone Tumour Service

The management of a case of Ewing's sarcoma of the left proximal humerus in a 15-year-old girl is presented, and the radiological and pathological findings are described. The chemotherapeutic, radiotherapeutic and surgical management of Ewing's sarcoma are discussed with reference to the case.

Topical calcipotriol treatment in advanced breast cancer

19 patients with locally advanced or cutaneous metastatic breast cancer were treated with the topical vitamin D analogue calcipotriol 100 micrograms daily. 14 patients completed 6 weeks' treatment; 3 showed a 50% reduction in the bidimensional diameter of treated lesions and 1 other patient showed a minimal response. 2 patients became hypercalcaemic during treatment. In all patients who responded the tumours contained receptors for 1,25-dihydroxyvitamin D3, shown by immunocytochemistry.