Prospective Evaluation of the 21-Gene Recurrence Score Assay for Breast Cancer Decision-Making in Ontario

Selecting postoperative adjuvant systemic therapy for early-stage breast cancer: An updated assessment and systematic review of leading commercially available gene expression assays

Gene expression assays (GEAs) can guide treatment for early-stage breast cancer. Several large prospective randomized clinical trials, and numerous additional studies, now provide new information for selecting an appropriate GEA. This systematic review builds upon prior reviews, with a focus on five widely commercialized GEAs (Breast Cancer Index®, EndoPredict®, MammaPrint®, Oncotype DX®, and Prosigna®). The comprehensive dataset available provides a contemporary opportunity to assess each GEA's utility as a prognosticator and/or predictor of adjuvant therapy benefit.

Oncotype DX results increase concordance in adjuvant chemotherapy recommendations for early-stage breast cancer

Adjuvant chemotherapy recommendations for ER+/HER2- early-stage breast cancers (eBC) involve integrating prognostic and predictive information which rely on physician judgment; this can lead to discordant recommendations. In this study we aim to evaluate whether Oncotype DX improves confidence and agreement among oncologists in adjuvant chemotherapy recommendations. We randomly select 30 patients with ER+/HER2- eBC and recurrence score (RS) available from an institutional database. We ask 16 breast oncologists with varying years of clinical practice in Italy and the US to provide recommendation for the addition of chemotherapy to endocrine therapy and their degree of confidence in the recommendation twice; first, based on clinicopathologic features only (pre-RS), and then with RS result (post-RS). Pre-RS, the average rate of chemotherapy recommendation is 50.8% and is higher among junior (62% vs 44%; p < 0.001), but similar by country. Oncologists are uncertain in 39% of cases and recommendations are discordant in 27% of cases (interobserver agreement K 0.47). Post-RS, 30% of physicians change recommendation, uncertainty in recommendation decreases to 5.6%, and discordance decreases to 7% (interobserver agreement K 0.85). Interpretation of clinicopathologic features alone to recommend adjuvant chemotherapy results in 1 out of 4 discordant recommendations and relatively high physician uncertainty. Oncotype DX results decrease discordancy to 1 out of 15, and reduce physician uncertainty. Genomic assay results reduce subjectivity in adjuvant chemotherapy recommendations for ER +/HER2- eBC.

Adherence Disparities and Utilization Trends of Oncotype Dx Assay: A National Cancer Database Study

INTRODUCTION

Oncotype Dx (ODX) is a genetic assay that analyzes tumor recurrence risk and provides chemotherapy recommendations for T1-T2 stage, hormone receptor-positive, human epidermal growth factor receptor-negative, and nodal-negative breast cancer patients. Despite its established validity, the utilization of this assay is suboptimal. The study aims to evaluate factors that are associated with adherence rate with the testing guidelines and examine changes in utilization trends.

METHODS

This is a retrospective study, utilizing data from the National Cancer Database from 2010 to 2017. Patients who met the ODX testing guidelines were first evaluated for testing adherence. Secondly, all patients who underwent ODX testing were assessed to evaluate the trend in ODX utilization.

RESULTS

A total of 429,648 patients met the criteria for ODX, and 43.4% of this population underwent testing. Advanced age, racial minorities, low-income status, well-differentiated tumor grade, uninsured status, and treatment at community cancer centers were associated with a decreased likelihood of receiving ODX in eligible patients. Additionally, a notable amount of testing was performed on patients who did not meet the ODX testing criteria. Among the 295,326 patients that underwent ODX testing, 16.6% of patients were node-positive and 1.8% had T3 or T4 stage tumors.

CONCLUSIONS

A considerable number of patients who were eligible for ODX did not receive it, indicating potential barriers to care and disparities in breast cancer treatment. ODX usage has been expanded to broader patient populations, indicating more research is needed to validate the effectiveness of the assay in these patient groups.

The Rochester Modified Magee Algorithm (RoMMa): An Outcomes Based Strategy for Clinical Risk-Assessment and Risk-Stratification in ER Positive, HER2 Negative Breast Cancer Patients Being Considered for Oncotype DX® Testing

INTRODUCTION

Multigene genomic profiling has become the standard of care in the clinical risk-assessment and risk-stratification of ER⁺, HER2^- breast cancer (BC) patients, with Oncotype DX^® (ODX) emerging as the genomic profile test with the most support from the international community. The current state of the health care economy demands that cost-efficiency and access to testing must be considered when evaluating the clinical utility of multigene profile tests such as ODX. Several studies have suggested that certain lower risk patients can be identified more cost-efficiently than simply reflexing all ER⁺, HER2^- BC patients to ODX testing. The Magee equations^TM use standard histopathologic data in a set of multivariable models to estimate the ODX recurrence score. Our group published the first outcome data in 2019 on the Magee equations^TM, using a modification of the Magee equations^TM combined with an algorithmic approach-the Rochester Modified Magee algorithm (RoMMa). There has since been limited published outcome data on the Magee equations^TM. We present additional outcome data, with considerations of the TAILORx risk-stratification recommendations.

METHODS

355 patients with an ODX recurrence score, and at least five years of follow-up or a BC recurrence were included in the study. All patients received either Tamoxifen or an aromatase inhibitor. None of the patients received adjuvant systemic chemotherapy.

RESULTS

There was no significant difference in the risk of recurrence in similar risk categories (very low risk, low risk, and high risk) between the average Modified Magee score and ODX recurrence score with the chi-square test of independence (p > 0.05) or log-rank test (p > 0.05). Using the RoMMa, we estimate that at least 17% of individuals can safely avoid ODX testing.

CONCLUSION

Our study further reinforces that BC patients can be confidently stratified into lower and higher-risk recurrence groups using the Magee equations^TM. The RoMMa can be helpful in the initial clinical risk-assessment and risk-stratification of BC patients, providing increased opportunities for cost savings in the health care system, and for clinical risk-assessment and risk-stratification in less-developed geographies where multigene testing might not be available.

Use of prognostic gene expression profiling tests in primary breast cancer treatment: a German real-world patient survey

Aims: In primary breast cancer, gene expression profiling tests can support adjuvant chemotherapy treatment decisions. Real-world test use in Germany was investigated in an online survey of female breast cancer patients (n = 475). Materials & methods: Relationships between three groups were examined for clinical and statistical relevance: no test indication (n = 353), test indication and tested (n = 65), and test indication but not tested (n = 57). Results: A total of 47% of participants with a test indication were not tested. Test rates increased by 23% from 2012-2018 (49%) to 2019-2021 (60%). A total of 65% of patients without testing received chemotherapy, whereas only 38% of tested patients received chemotherapy. Conclusion: The use of gene expression profiling tests correlates with a real-world chemotherapy reduction. Gene expression profiling testing may improve patient confidence in the decision for or against chemotherapy.

The Oncotype DX Recurrence Score's Impact on the Management of Oestrogen-Positive/Human Epidermal Growth Factor Receptor 2-Negative, Low-Burden Axillary Status Breast Cancer (REHAB Study): Results of a Single Centre

Background

The Oncotype DX Recurrence Score (ODX-RS) is increasingly utilized in oestrogen receptor (ER)-positive/human epidermal growth factor receptor 2 (HER2)-negative, low-burden axillary disease early operable breast cancer. It has been demonstrated to predict the benefits of adjuvant chemotherapy, hence supporting individualized decisions on adjuvant therapy.

Aim

To investigate the application of ODX-RS as an adjuvant treatment decision tool in breast cancer operated in our unit.

Methods

A total of 107 eligible patients who were operated on between 2017 and 2021 in Basildon University Hospital, UK were enrolled in this study. In this retrospective study, the clinical data, including patient’s age, tumour size, ER status, HER2 status, Ki67 proliferative index (Ki67-PI), nodal status, tumour grade, and ODX-RS, were collected. In the study design, the oncologist had the opportunity to assess the need for adjuvant chemotherapy for patients with ER-positive, HER2-negative, low-burden axillary lymph node disease, early breast cancer by using tumour characteristics and the PREDICT tool without knowing the ODX-RS results. The clinician's decision was matched against the breast multidisciplinary team's recommendations after ODX-RS utilisation, and the results were explored.

Results

The median ODX-RS of cohort tumours was 18 in the age group > 50 years, with ODX-RS ≥ 26 found in 18% of the group (n = 12). In the age group ≤ 50 years, 17% (n = 7) had ODX-RS between 21 and 25 and only 7% (n = 3) had ODX-RS ≥ 26. Without using ODX-RS, only 16% of the patients had been offered adjuvant chemotherapy in addition to the hormonal manipulation therapy; however, after using ODX-RS, up to 33% of the cohort was suitable for adjuvant chemotherapy in addition to the hormonal manipulation therapy. The changes in the recommendations after ODX-RS utilisation have been noticed in 29% of the cohort.

Conclusion

This study revealed that ODX-RS supported decision-making regarding postoperative adjuvant chemotherapy, especially when other tumour biomarkers, such as tumour size, grading, or Ki-67, indicated lower risk criteria. Patients with a high ODX-RS were offered chemotherapy where appropriate and its use led to a 15% rate of initial decision change in adjuvant treatment decisions; this involved either recommending chemotherapy or its omission.

Impact of TAILORx on chemotherapy prescribing and 21-gene recurrence score-guided treatment costs in a population-based cohort of patients with breast cancer

BACKGROUND

The trial assigning individualized options for treatment (Rx) (TAILORx) confirmed the predictive value of the 21-gene recurrence score (RS) assay in hormone receptor (HR)-positive, HER2-negative, node-negative breast cancer and established thresholds for chemotherapy benefit in younger and older patients. Real-world chemotherapy use and RS-guided treatment costs in British Columbia post-TAILORx were examined.

METHODS

The authors assembled 3 cohorts of HR-positive, HER2-negative, node-negative patients with breast cancer defined by diagnosis: before RS funding (cohort 1 [C1]: January 2013-December 2013), after introduction of public RS funding (cohort 2 [C2]: July 2015-June 2016), and after TAILORx results (cohort 3 [C3]: July 2018-June 2019). Chemotherapy use was compared between cohorts by age and RS. Budgetary impacts of RS testing on chemotherapy costs were evaluated pre- and post-TAILORx.

RESULTS

Among the 2066 patients included, chemotherapy use declined by 19% after RS funding was introduced and by an additional 23% after TAILORx publication (P = .001). Reduction in chemotherapy use was significant for RS 11-20 tumors (C3 vs C2, P = .004). There was no significant change in chemotherapy use in patients >50 years old (C2:12% vs C3:10%, P = .22). RS testing was associated with higher cost savings post-TAILORx, except in patients 70 to 80 years old, where testing led to excess costs when adjusting for the low rate of RS-concordant chemotherapy prescribed.

CONCLUSIONS

TAILORx has had population-based impacts on chemotherapy prescribing in intermediate RS tumors and patients ≤50 years old. The lower clinical use of RS and increased spending in patients 70-80 years old highlights the importance of careful selection of older candidates for high-cost genomic testing.

LAY SUMMARY

The 21-gene recurrence score (RS) test helps predict whether patients with hormone-positive, HER2-negative, lymph node-negative breast cancer are likely to benefit from chemotherapy. The recent trial assigning individualized options for treatment (Rx) (TAILORx) found that patients with intermediate RS tumors did not benefit from chemotherapy. The authors assessed whether TAILORx results translated to real-world changes in chemotherapy prescribing patterns. In this study, chemotherapy use decreased by 23% after TAILORx, with the greatest reductions seen among intermediate RS tumors and younger patients. In contrast, RS testing had lower clinical value and increased treatment costs in elderly patients, which requires further study to ensure optimal care for this age group.

Using Breast Cancer Gene Expression Signatures in Clinical Practice: Unsolved Issues, Ongoing Trials and Future Perspectives

The development of gene expression signatures since the early 2000's has offered standardized assays to evaluate the prognosis of early breast cancer. Five signatures are currently commercially available and recommended by several international guidelines to individualize adjuvant chemotherapy decisions in hormone receptors-positive/HER2-negative early breast cancer. However, many questions remain unanswered about their predictive ability, reproducibility and external validity in specific populations. They also represent a new hope to tailor (neo)adjuvant systemic treatment, adjuvant radiation therapy, hormone therapy duration and to identify a subset of patients who might benefit from CDK4/6 inhibitor adjuvant treatment. This review will highlight these particular issues, address the remaining questions and discuss the ongoing and future trials.

Who are the women who enrolled in the POSITIVE trial: A global study to support young hormone receptor positive breast cancer survivors desiring pregnancy

Background

Premenopausal women with early hormone-receptor positive (HR+) breast cancer receive 5–10 years of adjuvant endocrine therapy (ET) during which pregnancy is contraindicated and fertility may wane. The POSITIVE study investigates the impact of temporary ET interruption to allow pregnancy.

Methods

POSITIVE enrolled women with stage I-III HR + early breast cancer, ≤42 years, who had received 18–30 months of adjuvant ET and wished to interrupt ET for pregnancy. Treatment interruption for up to 2 years was permitted to allow pregnancy, delivery and breastfeeding, followed by ET resumption to complete the planned duration.

Findings

From 12/2014 to 12/2019, 518 women were enrolled at 116 institutions/20 countries/4 continents. At enrolment, the median age was 37 years and 74.9 % were nulliparous. Fertility preservation was used by 51.5 % of women. 93.2 % of patients had stage I/II disease, 66.0 % were node-negative, 54.7 % had breast conserving surgery, 61.9 % had received neo/adjuvant chemotherapy. Tamoxifen alone was the most prescribed ET (41.8 %), followed by tamoxifen + ovarian function suppression (OFS) (35.4 %). A greater proportion of North American women were <35 years at enrolment (42.7 %), had mastectomy (59.0 %) and received tamoxifen alone (59.8 %). More Asian women were nulliparous (81.0 %), had node-negative disease (76.2%) and received tamoxifen + OFS (56.0 %). More European women had received chemotherapy (69.3 %).

Interpretation

The characteristics of participants in the POSITIVE study provide insights to which patients and doctors considered it acceptable to interrupt ET to pursue pregnancy. Similarities and variations from a regional, sociodemographic, disease and treatment standpoint suggest specific sociocultural attitudes across the world.

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Fertility and pregnancy are priority concerns for young breast cancer survivors.

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POSITIVE explores a transient interruption of endocrine therapy to allow conception.

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Patients' characteristics highlight features considered suitable to study enrolment.

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Overall, patients enrolled had a relatively high median age and low-risk disease.

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Variations emerged across continents suggesting specific sociocultural attitudes.

Longitudinal patterns in fear of cancer progression in patients with rare, advanced cancers undergoing comprehensive tumour genomic profiling

INTRODUCTION

Fear of cancer progression (FCP) impacts quality of life and is a prevalent unmet need in patients diagnosed with advanced cancer, particularly as treatment options are reduced. We aimed to identify longitudinal patterns in FCP over 6 months in patients with advanced cancer receiving comprehensive tumour genomic profiling (CTGP) results, and their correlates.

METHODS

Patients with pathologically confirmed metastatic disease (∼70% rare cancers) receiving or post their last line of standard therapy completed questionnaires at T0 (prior to CTGP), T1 (immediately post CTGP results) and T2 (2 months later).

RESULTS

High stable (N = 52; 7.3%) and low/moderate stable (N = 56; 7.8%) FCP patterns over time typified the largest participant groups (N = 721). Those with an immediately actionable variant versus a non-actionable variant (p = 0.045), with higher FCP (p < 0.001), and lower Functional Assessment of Chronic Illness Therapy-Spiritual Well-being (FACIT-Sp) scores (p = 0.006) at T0, had higher FCP at T1. Those with higher FCP at T0 (p < 0.001) and at T1 (p < 0.001), lower FACIT-Sp scores at T1 (p = 0.001), lower education (p = 0.031) and female gender (p = 0.027) had higher FCP at T2.

DISCUSSION

Routine screening for psychological/spiritual characteristics in those about to undergo CTGP may help to identify patients who may benefit from closer monitoring and provision of psychosocial support. Future studies should explore interventions to best address FCP in this vulnerable group, as interventions assessed to date have almost all addressed patients with curative cancers or newly diagnosed advanced disease.

Cancer Patient Experience of Uncertainty While Waiting for Genome Sequencing Results

There is limited knowledge about cancer patients' experiences of uncertainty while waiting for genome sequencing results, and whether prolonged uncertainty contributes to psychological factors in this context. To investigate uncertainty in patients with a cancer of likely hereditary origin while waiting for genome sequencing results, we collected questionnaire and interview data at baseline, and at three and 12 months follow up (prior to receiving results). Participants (N = 353) had negative attitudes towards uncertainty (M = 4.03, SD 0.68) at baseline, and low levels of uncertainty at three (M = 8.23, SD 7.37) and 12 months (M = 7.95, SD 7.64). Uncertainty about genome sequencing did not change significantly over time [t(210) = 0.660, p = 0.510]. Greater perceived susceptibility for cancer [r(348) = 0.14, p < 0.01], fear of cancer recurrence [r(348) = 0.19, p < 0.01], perceived importance of genome sequencing [r(350) = 0.24, p < 0.01], intention to change behavior if a gene variant indicating risk is found [r(349) = 0.29, p < 0.01], perceived ability to cope with results [r(349) = 0.36, p < 0.01], and satisfaction with decision to have genome sequencing [r(350) = 0.52, p < 0.01] were significantly correlated with negative attitudes towards uncertainty at baseline. Multiple primary cancer diagnoses [B = -2.364 [-4.238, -0.491], p = 0.014], lower perceived ability to cope with results [B = -0.1.881 [-3.403, -0.359], p = 0.016] at baseline, greater anxiety about genome sequencing (avoidance) [B = 0.347 [0.148, 0.546], p = 0.0012] at 3 months, and greater perceived uncertainty about genome sequencing [B = 0.494 [0.267, 0.721] p = 0.000] at 3 months significantly predicted greater perceived uncertainty about genome sequencing at 12 months. Greater perceived uncertainty about genome sequencing at 3 months significantly predicted greater anxiety (avoidance) about genome sequencing at 12 months [B = 0.291 [0.072, 0.509], p = 0.009]. Semi-structured interviews revealed that while participants were motivated to pursue genome sequencing as a strategy to reduce their illness and risk uncertainty, genome sequencing generated additional practical, scientific and personal uncertainties. Some uncertainties were consistently discussed over the 12 months, while others emerged over time. Similarly, some uncertainty coping strategies were consistent over time, while others emerged while patients waited for their genome sequencing results. This study demonstrates the complexity of uncertainty generated by genome sequencing for cancer patients and provides further support for the inter-relationship between uncertainty and anxiety. Helping patients manage their uncertainty may ameliorate psychological morbidity.

Pursuing germline genome sequencing to reduce illness uncertainty may involve additional uncertainties for cancer patients: A mixed-methods study

Cancer-related illness uncertainty has been associated with poorer psychological outcomes for patients. While some cancer patients believe obtaining genomic information will reduce their illness uncertainty, the complexity of genomics has the potential to compound illness uncertainty. The aim of this mixed-methods study was to investigate uncertainty in patients with a cancer of likely heritable origin immediately following their decision to have germline genome sequencing. Participant (N = 348) negative attitudes toward uncertainty were associated with higher satisfaction with decision to have germline genome sequencing and greater fear of cancer recurrence. Thematic analysis of semi-structured interviews with a subset of participant (N = 20) revealed the following four themes: (a) germline genome sequencing to reduce illness uncertainty; (b) germline genome sequencing to reduce uncertainty related to relatives' risk; (c) uncertainty generated by germline genome sequencing; and (d) resilience and coping with uncertainty. This study demonstrated the complexity of uncertainty in germline genome sequencing in cancer patients. These results provide genomic healthcare professionals with important information about cancer patient's motivation to pursue germline genome sequencing, the specific uncertainties generated by germline genome sequencing, and how cancer patients cope with uncertainty.

Factors That Predict Biological Aggressiveness in Estrogen Receptor-Positive / Human Epidermal Growth Factor Receptor 2-Negative / Lymph Node-Negative Breast Cancer

Background: Traditionally, breast cancer is staged using TNM criteria: tumor size (T), nodal status (N), and metastasis (M). The Oncotype DX assay provides a recurrence score (RS) based on genomics that predicts the likelihood of distant recurrence in estrogen receptor–positive (ER+)/human epidermal growth factor receptor 2–negative (HER2–)/lymph node–negative (LN–) tumors.

Methods: We retrospectively reviewed the medical records of patients with ER+/HER2–/LN– breast cancer tumors who were evaluated between 2007 and 2017 with Oncotype DX RS. We compared the RS to tumor size, patient age, progesterone receptor (PR) status, and LN immunohistochemistry to assess for factors that may independently predict recurrence risk. We also compared tumor size to tumor grade.

Results: The data set included 296 tumors: 248 ER+/PR-positive (PR+)/HER2– and 48 ER+/PR-negative (PR–)/HER2–. RS ranged from 0 to 66, patient age ranged from 33 to 77 years, and tumor size ranged from 1 to 65 mm. No significant correlation was found between age and RS (r=–0.073, P=0.208). PR– tumors had a significantly higher RS regardless of size (PR– mean RS 30.8 ± 12.7; PR+ mean RS 16.3 ± 7.3; t(53)=7.6, P<0.0001). No significant correlation was seen between tumor size and RS for all tumors (r=–0.028, P=0.635), and this finding remained true for the PR+ tumor subgroup (r=0.114, P=0.072). However, a significant negative correlation was seen between tumor size and RS in the PR– subgroup (r=–0.343, P=0.017). Further analysis to ensure that differences in tumor grade did not account for this correlation showed equal distribution of well differentiated, moderately differentiated, and poorly differentiated tumors with no significant correlation between tumor size and grade.

Conclusion: Increasing tumor size may not be associated with increasing biological aggressiveness. Traditionally, smaller tumors are thought to be lower risk and larger tumors higher risk, with a tendency to use chemotherapy with large tumors. However, our data showed a negative correlation between tumor size and RS in the PR– subgroup. A tumor with PR negativity that reaches a large size without metastasizing may suggest a favorable tumor biology. These tumors may not receive as much benefit from chemotherapy as previously thought. Also, the higher RS seen in smaller PR– tumors may demonstrate PR– status as a predictor for higher risk of distant recurrence. We propose that all tumors meeting the ER+/PR–/LN– criteria, regardless of size, should be considered for genotyping, with the RS used to guide chemotherapy benefit.

Prognostic value of the 21-gene recurrence score in ER-positive, HER2-negative, node-positive breast cancer was similar in node-negative diseases: a single-center study of 800 patients

Multi-gene assays have emerged as crucial tools for risk stratification in early-stage breast cancer. This study aimed to evaluate the prognostic significance of the 21-gene recurrence score (RS) in Chinese patients with pN0-1, estrogen receptor-positive (ER⁺), human epidermal growth factor receptor 2-negative (HER2^-) breast cancer. Among 800 patients recruited between 2009 and 2016, the median RS was 24 (0-69), with 27.4%, 46.8%, and 25.9% patients classified into low-, intermediate-, and high-risk groups. Cox regression analysis demonstrated that the high-risk category was associated with significantly higher odds of invasive disease-free survival (IDFS) and distant disease-free survival (DDFS) events compared with the low-risk category (IDFS: HR = 2.450, 95% CI 1.017-5.902, P = 0.046; DDFS: HR = 2.829, 95% CI 1.013-7.901, P = 0.047). No significant association between RS category and overall survival (OS) was found (intermediate vs. low: HR= 1.244, 95% CI 0.292-5.297, P = 0.768; high vs. low: HR = 2.933, 95% CI 0.759-11.327, P = 0.119). RS, as a continuous variable, was a highly significant predictor for IDFS (HR= 1.028, 95% CI 1.010-1.047, P = 0.002), DDFS (HR= 1.030, 95% CI 1.010-1.051, P = 0.003), and OS (HR= 1.034, 95% CI 1.007-1.063, P = 0.014). Our findings suggested that RS may predict IDFS in Chinese patients with ER⁺/HER2^- breast cancer with N0 or N1 disease.

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.

Question Prompt List to Support Patient-Provider Communication in the Use of the 21-Gene Recurrence Test: Feasibility, Acceptability, and Outcomes

PURPOSE

The 21-gene recurrence score (RS) assay is used to guide breast cancer treatment decisions but can be poorly understood by patients. We examined the effects of a question prompt list (QPL) on knowledge, distress, and decisional conflict related to genomic testing and treatment in early-stage breast cancer.

METHODS

We describe the feasibility and acceptability of the QPL and the impact of the QPL on knowledge, distress, and decisional conflict before and after the receipt of the QPL (MEND 2, N = 65). We also compared distress and decisional conflict between women who received the QPL (MEND 2, N = 65) and a comparable group of women who did not receive the QPL who participated in an earlier observational study within the same clinics (MEND 1, N = 136).

RESULTS

MEND 2 participants indicated high acceptability and feasibility using the QPL. Knowledge increased post-QPL (P < .01) but did not decrease distress. Decisional conflict was lower among women in MEND 2 compared with those in MEND 1 (P < .01), with no statistically significant differences in distress.

CONCLUSION

The findings suggest that the QPL is feasible, acceptable, can improve knowledge and decrease decisional conflict in the large group of women deciding treatment while integrating RS test results.

Precision radiotherapy for non-small cell lung cancer

Precision medicine is becoming the standard of care in anti-cancer treatment. The personalized precision management of cancer patients highly relies on the improvement of new technology in next generation sequencing and high-throughput big data processing for biological and radiographic information.

Systemic precision cancer therapy has been developed for years. However, the role of precision medicine in radiotherapy has not yet been fully implemented. Emerging evidence has shown that precision radiotherapy for cancer patients is possible with recent advances in new radiotherapy technologies, panomics, radiomics and dosiomics.

This review focused on the role of precision radiotherapy in non-small cell lung cancer and demonstrated the current landscape.

Patients' perceptions of 70-gene signature testing: commonly changing the initial inclination to undergo or forego chemotherapy and reducing decisional conflict

PURPOSE

Little is known about the impact of 70-gene signature (70-GS) use on patients' chemotherapy decision-making. The primary aim of this study was to evaluate the impact of 70-GS use on patients' decisions to undergo chemotherapy. The perceived decision conflict during decision-making was a secondary objective of the study.

METHODS

Patients operated for estrogen receptor positive early breast cancer were asked to fill out a questionnaire probing their inclination to undergo chemotherapy before deployment of the 70-GS test. After disclosure of the 70-GS result patients were asked about their decision regarding chemotherapy. Patients' decisional conflict was measured using the 16-item decisional conflict scale (DCS); scores < 25 are associated with a persuaded decision while a score > 37.5 implies that one feels unsure about a choice.

RESULTS

Between January 1th 2017 and December 31th 2018, 106 patients completed both questionnaires. Before deployment of the 70-GS, 58% of patients (n = 62) formulated a clear treatment preference, of whom 21 patients (34%) changed their opinion on treatment with chemotherapy following the 70-GS. The final decision regarding chemotherapy was in line with the 70-GS result in 90% of patients. The percentage of patients who felt unsure about their preference to be treated with chemotherapy decreased from 42 to 5% after disclosure of the 70-GS. The mean total DCS significantly decreased from pre-test to post-test from 35 to 23, irrespective of the risk estimate (p < 0.001).

CONCLUSION

Deployment of the 70-GS changed patients' inclination to undergo adjuvant chemotherapy in one third of patients and decreased patients' decisional conflict.

Clinicopathological characteristics, adjuvant chemotherapy decision and disease outcome in patients with breast cancer with a 21-gene recurrence score of 26-30

Recurrence score (RS) could be used to predict clinical outcomes and chemotherapy efficacy in patients with hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative and lymph node-negative breast cancer. However, the clinical features and management of patients with an RS of 26–30 are not completely understood. In the present study, 783 patients with HR⁺/HER2⁻, lymph node-negative early breast cancer and RS ≥18 were included and categorized into RS=18−25 (47.8%), 26–30 (25.5%) or ≥31 (26.7%) groups. Clinicopathological characteristics, adjuvant chemotherapy usage and disease outcomes were compared. Alterations in the adjuvant chemotherapy recommendation after 21-gene RS testing were also analyzed. The results indicated that patients with RS=26−30 had higher progesterone receptor (PR) expression [odds ratio (OR)=2.84; P<0.001] and lower Ki-67 index (OR, 1.88; P=0.032) compared with patients with RS ≥31. Multivariate analysis demonstrated that age ≤50 years (OR, 5.75; P=0.001) and luminal-B subtype (OR, 7.75; P<0.001) were factors that were independently associated with chemotherapy usage in the RS=26−30 group. Among 104 patients who were not recommended chemotherapy before 21-gene RS testing, the treatment decision for 52 patients was changed to recommend chemotherapy once an RS of 26–30 was identified. The patient adherence rate to the treatment recommendation was 95.0% (190/200). After a median follow-up of 21.5 months, 6 patients displayed disease recurrence in the RS=26−30 group, and there was no significant difference between patients receiving chemotherapy and patients not receiving chemotherapy. In conclusion, patients with RS=26−30 had tumors with higher PR expression and lower Ki-67 index compared with those of patients with RS ≥31. Age, luminal subtype and RS testing influenced chemotherapy usage in patients with RS=26−30; however, no significant benefit from adjuvant chemotherapy was observed in a short term of 2 years.

Multigene testing in breast cancer: What have we learned from the 21-gene recurrence score assay?

Most invasive breast cancers express hormone receptors (HR) and typically have a favorable prognosis following endocrine therapy. Patients at a higher risk of recurrence can be identified by multigene prognostic classifiers such as the 21-gene recurrence score (RS) assay, 70-gene prognostic signature, PAM-50, 12-gene molecular score, and others. The 21-gene RS assay (Oncotype Dx™, Genomic Health, Redwood City, CA) has level I clinical evidence and is the most widely used multigene assay in North America. The RS assay is based on reverse transcriptase polymerase chain reaction that can be performed on the RNA isolated from formalin-fixed paraffin-embedded tissue. It evaluates the expression of 16 cancer-related genes developed based on a multi-step approach. Due to its ability to assess recurrence risk and predict potential benefit from chemotherapy, the assay is recommended for patients with node-negative, HR-positive, and human epidermal growth factor receptor 2 (HER2)-negative breast cancer by the American Society of Clinical Oncology, National Comprehensive Cancer Network clinical practice guidelines in oncology, European Society for Medical Oncology clinical practice guidelines, and St. Gallen consensus panel guidelines. The RS assay has also been incorporated in the prognostic stage groups in the 8th edition of the American Joint Commission of Cancer staging manual in order to provide essential genomic information for optimal treatment decisions. This review will focus on the utility of the RS assay in HR-positive and HER2-negative breast cancer patients, including risk of distant and locoregional recurrence in node-negative and node-positive tumors, association with radiotherapy, special subtypes of breast cancer, practical issues related to selecting tumors for testing, and overview of the recently published TailorX (Trial Assigning IndividuaLized Options for treatment [Rx]) results.

Patient experience of uncertainty in cancer genomics: a systematic review

While genomics provides new clinical opportunities, its complexity generates uncertainties. This systematic review aimed to summarize what is currently known about the experience of uncertainty for adult patients undergoing cancer genomic testing. A search of five databases (2001 to 2018) yielded 6508 records. After removing duplicates, abstract/title screening, and assessment of full articles, ten studies were included for quality appraisal and data extraction. Qualitative studies were subjected to thematic analysis, and quantitative data were summarized using descriptive statistics. Cancer genomic results reduced uncertainty for patients regarding treatment decisions but did not reduce uncertainty in the risk context. Qualitative and quantitative data synthesis revealed four themes: (1) coexisting uncertainties, (2) factors influencing uncertainty, (3) outcomes of uncertainty, and (4) coping with uncertainty. Uncertainty can motivate, or be a barrier to, pursuing cancer genomic testing. Appraisal of uncertainty influences the patient experience of uncertainty, the outcome of uncertainty for patients, as well as the coping strategies utilized. While this systematic review found that appraisal of uncertainty is important to the patients' experience of uncertainty in the cancer genomic context, more mixed methods longitudinal research is needed to address the complexities that contribute to patient uncertainty across the process.

Impact of Recurrence Score on type and duration of chemotherapy in breast cancer

Background

The use of Oncotype dx (Genomic Health, Redwood City, CA, U.S.A.) testing has been shown to change treatment decisions in approximately 30% of breast cancer (bca) cases, but research on how Recurrence Score testing has affected the type of chemotherapy offered is limited. We sought to determine if the availability of Oncotype dx testing resulted in a change to the type and duration of chemotherapy regimens used in the treatment of early-stage hormone receptor-positive bca.

Methods

In a population-based cohort study, patients treated in the 2 years before the availability of Oncotype dx testing were compared with patients treated in the 2 years after testing availability. Charts were audited and divided into 2 groups: pre-Oncotype dx and post-Oncotype dx. The groups were compared for differences in duration of chemotherapy (12 weeks vs. >12 weeks), types of agents used (anthracycline vs. non-anthracycline), and myelosuppressive potential of the chosen regimen.

Results

Of 834 patients who fulfilled the enrolment criteria, 360 fell into the pre-Oncotype dx era, and 474, into the post-Oncotype dx era. An increase of 11.2 percentage points, to 69.5% from 58.3%, was observed in the proportion of patients receiving short-course compared with long-course chemotherapy (p = 0.068). The proportion of patients prescribed anthracycline-containing regimens declined in the post-Oncotype dx era (47.7% pre vs. 32.2% post, p = 0.016). The selection of more-myelosuppressive chemotherapy protocols increased in the post-Oncotype dx era (67.4% pre vs. 78.8% post, p = 0.044).

Conclusions

In the present study, the availability of Oncotype dx testing was observed to influence the choice of chemotherapy type in the setting of early-stage bca.

Implications of the 21-gene recurrence score assay (Oncotype DX) on adjuvant treatment decisions in ER-positive early-stage breast cancer patients: experience of Kuwait Cancer Control Center

BACKGROUND

The Oncotype DX is a quantitative assay of the expression of 16 tumor-related genes and 5 reference genes that predicts the potential of adjuvant chemotherapy benefit in estrogen receptor (ER)-positive early breast cancer patients. The study aims to evaluate the impact of Oncotype DX as a tool for adjuvant treatment decision of ER-positive, HER2-negative, N0/N1 early-stage breast cancer patients and to determine which clinicopathological criteria derived the greatest advantage.

RESULTS

A hundred patients at a median age of 50 years were included. TNM stage distribution was 34, 63, and 3 patients for stages I, II, and IIIA respectively. Fifty-four patients had luminal A and 46 had luminal B tumors. The recurrence score (RS) results were low, intermediate, and high risk in 54, 34, and 12 patients respectively. Before the test results, adjuvant chemoendocrine therapy (CET) was recommended for 46 patients while 54 were advised for endocrine therapy (ET). After getting the test results, 25 patients received CET (1, 12, and12 patients in the low-, intermediate-, and high-risk groups respectively) and 75 received ET. Treatment change was documented in 37 patients (8 patients from ET to CET and 29 from CET to ET; p = 0.001, McNemar test). Treatment change was significant among patients ≤ 50 years, luminal B tumors, stage II and IIIA disease, and node-positive disease.

CONCLUSION

Oncotype DX testing resulted in significant changes in the adjuvant treatment decisions in ER-positive, HER2-negative early breast cancer particularly in the case of young, luminal B, N1, and stage II-IIIA disease.

Molecular Decision Tree Algorithms Predict Individual Recurrence Pattern for Locally Advanced Nasopharyngeal Carcinoma

Background: Recurrence remains one of the key reasons of relapse after the radical radiation for locally advanced nasopharyngeal carcinoma (NPC). Here, the multiple molecular and clinical variables integrated decision tree algorithms were designed to predict individual recurrence patterns (with VS without recurrence) for locally advanced NPC.

Methods: A total of 136 locally advanced NPC patients retrieved from a randomized controlled phase III trial, were included. For each patient, the expression levels of 33 clinicopathological biomarkers in tumor specimen, 3 Epstein-Barr virus related serological antibody titer and 5 clinicopathological variables, were detected and collected to construct the decision tree algorithm. The expression level of 33 clinicopathological biomarkers in tumor specimen was evaluated by immunohistochemistry staining.

Results: Three algorithm classifiers, augmented by the adaptive boosting algorithm for variable selection and classification, were designed to predict individual recurrence pattern. The classifiers were trained in the training subset and further tested using a 10-fold cross-validation scheme in the validation subset. In total, 13 molecules expression level in tumor specimen, including AKT1, Aurora-A, Bax, Bcl-2, N-Cadherin, CENP-H, HIF-1α, LMP-1, C-Met, MMP-2, MMP-9, Pontin and Stathmin, and N stage were selected to construct three 10-fold cross-validation decision tree classifiers. These classifiers showed high predictive sensitivity (87.2-93.3%), specificity (69.0-100.0%), and overall accuracy (84.5-95.2%) to predict recurrence pattern individually. Multivariate analyses confirmed the decision tree classifier was an independent prognostic factor to predict individual recurrence (algorithm 1: hazard ration (HR) 0.07, 95% confidence interval (CI) 0.03-0.16, P < 0.01; algorithm 2: HR 0.13, 95% CI 0.04-0.44, P < 0.01; algorithm 3: HR 0.13, 95% CI 0.03-0.68, P = 0.02).

Conclusion: Multiple molecular and clinicopathological variables integrated decision tree algorithms may individually predict the recurrence pattern for locally advanced NPC. This decision tree algorism provides a potential tool to select patients with high recurrence risk for intensive follow-up, and to diagnose recurrence at an earlier stage for salvage treatment in the NPC endemic region.

The Oncotype Dx Assay in ER-Positive, HER2-Negative Breast Cancer Patients: A Real Life Experience from a Single Cancer Center

Objective

To determine the influence of the Oncotype Dx assay on the treatment of patients with Estrogen Receptor (ER)-positive, Human Epidermal Growth Factor Receptor 2 (HER2)-negative, axillary lymph node-negative or micrometastatic carcinoma of the breast in a single cancer center. In addition, patients with intermediate Oncotype Dx recurrence scores were analyzed to assess the factors influencing therapeutic decisions for adjuvant chemotherapy.

Materials and Methods

Data from medical records of women diagnosed with carcinoma of the breast and qualified for the Oncotype Dx assay were extracted (OncoDx cohort). Patient demographic and cancer characteristics, genomic report, and course of treatment data, including survival outcomes and treatment decision-making, were analyzed. A matched cohort of patients with similar tumor stage and biology (ER-positive, HER2-negative) from the era before the introduction of the Oncotype Dx assay was analyzed for comparison (pre-OncoDx cohort).

Results

Two hundred and one patients were included in the OncoDx cohort and one hundred and sixty patients were included in the pre-OncoDx cohort. Oncotype Dx recurrence score (RS) was low (<11) in fifty-six patients (28%), intermediate (11-25) in one hundred and twenty-three patients (61.5%) and high (>25) in twenty one patients (10.5%). Demographic and cancer clinicopathologic characteristics between OncoDx and pre-OncoDx cohorts were similar. Overall, 10.9% of the patients in the OncoDx cohort received adjuvant chemotherapy, versus 23.8% of the patients in the pre-OncoDx cohort (Fisher exact p=0.003). Fewer patients were recommended adjuvant chemotherapy in the OncoDx era compared to the pre-OncoDx era (17.9% vs 30.6%, respectively, Fisher exact p=0.006). The decision to recommend chemotherapy within the intermediate-risk cohort was influenced by the patient's RS. The mean RS of patients in the intermediate-risk cohort who did not receive chemotherapy was 21.5 while the score of those that received chemotherapy was 24.6 (p=0.000). The series confirmed excellent PFS and OS for both OncoDx and pre-OncoDx cohorts.

Conclusion

This single cancer center analysis confirms the avoidance of chemotherapy in the great majority of patients with early ER-positive, HER2-negative, lymph node-negative or micrometastatic carcinoma of the breast since the introduction of the Oncotype Dx assay. A higher recurrence risk score within the intermediate group may influence the decision for chemotherapy inclusion in the adjuvant treatment plan. A lower PR percentage by IHC and higher grade may predict higher Oncotype Dx scores.

Cost-effectiveness analysis of multigene expression profiling assays to guide adjuvant therapy decisions in women with invasive early-stage breast cancer

Gene expression profiling (GEP) testing using 12-gene recurrence score (RS) assay (EndoPredict®), 58-gene RS assay (Prosigna®), and 21-gene RS assay (Oncotype DX®) is available to aid in chemotherapy decision-making when traditional clinicopathological predictors are insufficient to accurately determine recurrence risk in women with axillary lymph node-negative, hormone receptor-positive, and human epidermal growth factor-receptor 2-negative early-stage breast cancer. We examined the cost-effectiveness of incorporating these assays into standard practice. A decision model was built to project lifetime clinical and economic consequences of different adjuvant treatment-guiding strategies. The model was parameterized using follow-up data from a secondary analysis of the Anastrozole or Tamoxifen Alone or Combined randomized trial, cost data (2017 Canadian dollars) from the London Regional Cancer Program (Canada) and secondary Canadian sources. The 12-gene, 58-gene, and 21-gene RS assays were associated with cost-effectiveness ratios of $36,274, $48,525, and $74,911/quality-adjusted life year (QALY) gained and resulted in total gains of 379, 284.3, and 189.5 QALYs/year and total budgets of $12.9, $14.2, and $16.6 million/year, respectively. The total expected-value of perfect information about GEP assays' utility was $10.4 million/year. GEP testing using any of these assays is likely clinically and economically attractive. The 12-gene and 58-gene RS assays may improve the cost-effectiveness of GEP testing and offer higher value for money, although prospective evidence is still needed. Comparative field evaluations of GEP assays in real-world practice are associated with a large societal benefit and warranted to determine the optimal and most cost-effective assay for routine use.

Practical Consequences Resulting from the Analysis of a 21-Multigene Array in the Interdisciplinary Conference of a Breast Cancer Center

During the multidisciplinary planning of postoperative therapy after breast cancer, borderline cases can arise with no clear rationale for or against adjuvant chemotherapy. In 50 hormone- receptor-positive, Her2neu-negative carcinomas of the breast with no or only minimal lymph node involvement (max. pT1a) we initiated an Oncotype DX® multigene assay in addition to the evaluation of usual parameters. In the oncology conference a vote for or against chemotherapy was taken on the basis of the conventional criteria for decision-making before the test results were available. The final recommendation was made after the multigene test. In 32 breast carcinomas (64%) a low recurrence score could be documented, while 26 (32%) showed an intermediate RS and 3 (6%) showed a high RS. In most cases the result of the test could validate the choice of therapy established using conventional criteria. In 5 cases the initial recommendation for adjuvant therapy was revised, and in 3 cases chemotherapy was secondarily recommended after evaluation of the test results. Conversely, in some cases a low or intermediate risk constellation did not argue against a recommendation for adjuvant chemotherapy. Altogether, the results of our study do not indicate that a multigene assay should be used as a routine diagnostic tool. Instead a thorough compilation and careful analysis of conventional parameters for therapeutic decision-making should take precedence, with special emphasis on histopathological and immunohistochemical results. In selected cases, however, a multigene assay can be a useful tool in the deliberation for or against a therapeutic pathway.

The 21-Gene Recurrence Score in Male Breast Cancer

BACKGROUND

Given the limited data, systemic treatment of male breast cancer has been extrapolated from female patients. The 21-gene recurrence score (RS) assay estimates the risk of distant recurrence and chemotherapy benefit in early-stage, ER+/HER2- female breast cancer. We assessed the association between RS and type of treatment in male breast cancer.

METHODS

We identified male patients with ER+/HER2- breast cancer and available RS results treated at our institution in 2006-2016. We collected data on clinicopathologic features, treatment, and outcome. The Institutional Review Board approved the study.

RESULTS

The study cohort consists of 38 male breast cancer patients with a median age of 70 years. Median tumor size was 1.6 cm, and 81.6% (31) were node-negative. RS was low (≤ 17) in 26 (68.4%) cases, intermediate (18-30) in 9 (23.7%) cases, and high (≥ 31) in 3 (7.9%) cases, comparable to that in female patients at our institution. All patients underwent total mastectomy, and one received radiotherapy. Thirty-four (89.5%) patients received adjuvant endocrine therapy, mostly tamoxifen (81.6%; 31). Five (13.2%) patients with intermediate or high RS were treated with adjuvant chemotherapy. No locoregional recurrence was observed, and one patient developed distant recurrence (median follow-up 34 months).

CONCLUSIONS

The RS distribution in male breast cancers was similar to that in females treated at our institution. With limited follow-up, patients with low RS were spared chemotherapy and did not develop recurrence. Our results suggest that the RS may have a clinical utility in male breast cancer patients.

Multigene Signature Panels and Breast Cancer Therapy: Patterns of Use and Impact on Clinical Decision Making

BACKGROUND

A growing body of evidence supports the use of multigene signature panels (MSPs) in predicting recurrence risk in patients with invasive breast cancer. This study aimed to evaluate trends in MSP use over time and the effect of MSPs on administration of postoperative chemotherapy.

STUDY DESIGN

The National Cancer Database was queried for all women with invasive breast cancer who underwent resection between 2011 and 2014 and had information about performance of an MSP, hormone receptor status, and receipt of chemotherapy. Multigene signature panel use over time was evaluated, and patterns of use of Oncotype DX (ODX) and MammaPrint (MP) were compared.

RESULTS

In a total of 476,128 patients, an MSP was obtained in 153,782 (30.2%). Multigene signature panel use increased over time and was associated with a decreased rate of chemotherapy administration (24.6% MSP vs 37.2% no MSP; p < 0.001). Oncotype DX remained the most common MSP used throughout the study period. Oncotype DX was used more commonly in stage I disease than MP, and MP was used more commonly in stage II and III disease. MammaPrint was more commonly used in hormone receptor-negative patients, human epidermal growth factor receptor 2-positive patients, and patients with positive lymph nodes. Postoperative chemotherapy was administered to a higher proportion of patients assessed with MP than with ODX (41.3% vs 23.4%, respectively; p < 0.001).

CONCLUSIONS

Use of MSPs among patients with breast cancer has increased over time and is associated with a decreased use of adjuvant chemotherapy. Oncotype DX continues to be the most widely used MSP, although MP use has increased over time. Future studies are warranted to determine the optimal use of these MSPs in risk assessment and postoperative decision making.

Prospective Evaluation of the Impact of the 21-Gene Recurrence Score Assay on Adjuvant Treatment Decisions for Women with Node-Positive Breast Cancer in Ontario, Canada

BACKGROUND

The 21-gene Recurrence Score (RS) assay is only reimbursed in Ontario for node-negative and micrometastatic node-positive (N+) early-stage breast cancer (EBC). We carried out a prospective study to evaluate the impact of the assay on treatment decisions for women with N+ EBC.

SUBJECTS, MATERIALS, AND METHODS

Women with estrogen receptor-positive, human epidermal growth receptor 2-negative EBC and one to three positive axillary lymph nodes, who were candidates for adjuvant chemotherapy in addition to hormonal treatment, but in whom the benefit of chemotherapy was uncertain, were eligible. The primary objective was to characterize how the results of the RS assay affected physicians' recommendations for adjuvant chemotherapy. Secondary objectives were to characterize changes in the physicians' and patients' level of confidence in treatment recommendations, to determine whether the results of the RS assay affected patients' treatment preferences, and to determine the final treatment administered.

RESULTS

Seventy-two patients were recruited; the mean age was 61. RS was <18 in 55%, between 18 and 30 in 36%, and ≥31 in 9% of patients. Treatment recommendations changed in 36% of all evaluable patients. The most significant change was in the group with a low RS. Physicians' and patients' confidence in treatment recommendations increased in 49% and 54% of cases, respectively. Upfront chemotherapy was recommended to 79% of patients before the assay; 42% ultimately received chemotherapy.

CONCLUSION

The RS assay resulted in a substantial decrease in the number of patients who received chemotherapy and in an increase in physicians' and patients' confidence in the adjuvant treatment recommendations.

IMPLICATIONS FOR PRACTICE

This is the first decision impact study to include exclusively women with ER-positive, HER2-negative, early-stage breast cancer with 1-3 positive lymph nodes, a population typically treated with adjuvant chemotherapy. This study provides evidence that, in these patients, the Oncotype Dx Recurrence Score assay influences systemic treatment decisions. Most of the changes in treatment recommendation resulted in withdrawal of chemotherapy or change in recommendation from a chemotherapy regimen with anthracyclines to a taxane-only regimen. If prospective studies confirm that these decisions result in good outcomes, a reduction in the use of chemotherapy might result in pharmacoeconomic savings.

Breast carcinoma with 21-gene recurrence score lower than 18: rate of locoregional recurrence in a large series with clinical follow-up

BACKGROUND

The 21-gene recurrence score (RS) assay determines the benefit of adding chemotherapy to endocrine therapy for patients with early stage, estrogen receptor (ER)-positive, HER2-negative breast cancer. The RS risk groups predict the likelihood of distant recurrence and have recently been associated with an increased risk of locoregional recurrence (LRR). This study analyzed clinicopathologic features of patients with low RS and LRR.

METHODS

In our institutional database, we identified 1396 consecutive female patients with lymph node negative, ER+/HER2- invasive breast carcinoma and low RS (<18) results, treated at our center from 2008 to 2013. We collected data on clinicopathologic features, treatment and outcome.

RESULTS

The median patient age was 57 years (range 22-90). The median tumor size was 1.2 cm (range 0.3-5.8). Overall, 66.6% (930/1396) women were treated with breast conserving surgery (BCS) and radiation therapy, 3.4% (48/1396) with BCS alone, 29.7% (414/1396) with total mastectomy, and 0.3% (4/1396) with total mastectomy and radiation therapy. Most patients (84.8%; 1184/1396) received endocrine therapy alone, 12.1% (169/1396) were treated with chemotherapy plus endocrine therapy, and only 3.1% (43/1396) received no systemic therapy. At a median follow-up of 52 months, 0.9% (13/1396) of patients developed LRR. Sites of LRR included the ipsilateral breast (n = 8), chest wall (n = 3), axillary node (n = 1), and internal mammary node (n = 1). All patients with LRR had negative resection margins at the initial surgery. The rate of LRR in patients treated with adjuvant endocrine therapy alone was 0.7% (8/1184). All eight patients received standard local treatment. Three patients had lymphovascular invasion but no other significant risk factors for LRR were identified.

CONCLUSIONS

Our study of node negative, ER+/HER2- breast cancer patients with low RS observed extremely low rates of LRR: 0.9% (13/1396) in the whole cohort and 0.7% (8/1184) in patients treated with endocrine therapy alone. As the largest series to date, we report detailed clinicopathologic data and clinical outcomes of this cohort and provide a comprehensive characterization of patients who developed LRR.

Population-Based Study to Determine the Health System Costs of Using the 21-Gene Assay

Purpose The 21-gene assay Oncotype Dx (Genomic Health, Redwood City, CA) test is used to aid the decision about chemotherapy in patients with hormone receptor-positive breast cancer who received endocrine therapy. Economic studies to support test adoption used decision-analytic models with assumptions and data derived from disparate sources. The objective was to evaluate whether the 21-gene assay test resulted in an overall cost expense or saving to the health system. Patients and Methods One thousand participants enrolled in a field evaluation study, were linked to population-level health system administrative databases, and were observed for 20 months. The cost for the cohort, which included the cost of the test, subsequent treatments received, and health care encounters, was determined. The cost in the absence of the test was compared with the pretest recommendation about chemotherapy from the field study for a base case and under scenarios that reflected different adjuvant chemotherapy use. Overall health system costs and incremental costs were calculated. Results The 21-gene assay resulted in a net decrease in chemotherapy use of 23%. For the base case incremental analysis, the actual overall health system cost of this cohort, including the cost of 21-gene assay, was $29.2 million compared with $26.2 million in the absence of the test-an increase of $3.1 million. For three of the four scenario analyses, the actual overall cost to the health system exceeded the estimated cost in the absence of the test. Results showed that, when at least half of the population received adjuvant chemotherapy, the cost increased to $30.2 million. Conclusion The use of real-world administrative data showed that, despite lower rates of chemotherapy use, the 21-gene assay test results in an overall incremental cost to the health care system in the short-term under most assumptions.

First Prospective Multicenter Italian Study on the Impact of the 21-Gene Recurrence Score in Adjuvant Clinical Decisions for Patients with ER Positive/HER2 Negative Breast Cancer

BACKGROUND

The Breast DX Italy prospective study evaluated the impact of the 21-gene recurrence score (RS) result on adjuvant treatment decisions for patients with early breast cancer.

MATERIALS AND METHODS

Nine centers (two Hub and seven Spoke centers of the Veneto Oncology Network) participated. Consecutive patients with estrogen receptor positive, human epidermal growth receptor negative, T1-T3, N0-N1 early breast cancer were prospectively registered; only those meeting protocol-defined clinicopathological "intermediate risk" criteria were eligible for the RS test. Pre-RS and post-RS physicians' treatment recommendations and treatment actually received were collected.

RESULTS

A total of n = 124 N0 and n = 126 N1 patients underwent the RS assay. The majority had Grade 2 tumors (71%); median age was 55 years, median tumor size was 16 mm, and median Ki67 expression was 20%. Patients enrolled at Hub centers presented higher-risk features. The distribution of RS results was <18 (60.8%), 18-30 (32.4%), and >30 (6.8%). The indication before RS was hormonal therapy (HT) alone in 52% of cases. An indication before RS of chemotherapy (CT)+HT was more frequent for patients with N1 versus N0 tumors (57% vs. 39%, p = .0035) and for patients enrolled at Hub versus Spoke centers (54% vs. 36%, p = .007).The overall rate of change in treatment decision was 16% (n = 40), mostly from CT+HT to HT (n = 30). According to nodal status, rate of change in treatment decision was 12% for the N0 cohort and 20% for the N1 cohort. The proportion of patients recommended to CT+HT was significantly reduced from before to after RS (48% to 40%, p < .0016), especially in the N1 cohort (57% to 45%, p = .0027) and at Hub centers (54% to 44%, p = .001).

CONCLUSION

Despite frequent indication of HT before RS, the use of the RS assay further contributed to sparing CT, especially for patients with N1 tumors and at Hub centers.

IMPLICATIONS FOR PRACTICE

This study shows that, although a high proportion of patients were recommended to receive endocrine treatment alone before knowing the recurrence score (RS) assay, the RS test further contributed in sparing chemotherapy for some of these patients, especially in case of the N1 stage or for patients enrolled at referral centers. These data highlight the need for further work in collaboration with health authorities and companies in order to define strategies for the implementation of the use of RS testing in clinical practice in the Italian setting.

Systematic review of the clinical and economic value of gene expression profiles for invasive early breast cancer available in Europe

Gene expression profiles with prognostic capacities have shown good performance in multiple clinical trials. However, with multiple assays available and numerous types of validation studies performed, the added value for daily clinical practice is still unclear. In Europe, the MammaPrint, OncotypeDX, PAM50/Prosigna and Endopredict assays are commercially available. In this systematic review, we aim to assess these assays on four important criteria: Assay development and methodology, clinical validation, clinical utility and economic value. We performed a literature search covering PubMed, Embase, Web of Science and Cochrane, for studies related to one or more of the four selected assays. We identified 147 papers for inclusion in this review. MammaPrint and OncotypeDX both have evidence available, including level IA clinical trial results for both assays. Both assays provide prognostic information. Predictive value has only been shown for OncotypeDX. In the clinical utility studies, a higher reduction in chemotherapy was achieved by OncotypeDX, although the number of available studies differ considerably between tests. On average, economic evaluations estimate that genomic testing results in a moderate increase in total costs, but that these costs are acceptable in relation to the expected improved patient outcome. PAM50/prosigna and EndoPredict showed comparable prognostic capacities, but with less economical and clinical utility studies. Furthermore, for these assays no level IA trial data are available yet. In summary, all assays have shown excellent prognostic capacities. The differences in the quantity and quality of evidence are discussed. Future studies shall focus on the selection of appropriate subgroups for testing and long-term outcome of validation trials, in order to determine the place of these assays in daily clinical practice.

Clinical utility of multigene profiling assays in early-stage breast cancer

BACKGROUND

This clinical practice guideline was developed to determine the level of evidence supporting the clinical utility of commercially available multigene profiling assays and to provide guidance about whether certain breast cancer patient populations in Ontario would benefit from alternative tests in addition to Oncotype dx (Genomic Health, Redwood City, CA, U.S.A.).

METHODS

A systematic electronic Ovid search of the medline and embase databases sought out systematic reviews and primary literature. A systematic review and practice guideline was written by a working group and was then reviewed and approved by Cancer Care Ontario's Molecular Oncology Advisory Committee.

RESULTS

Twenty-four studies assessing the clinical utility of Oncotype dx, Prosigna (NanoString Technologies, Seattle, WA, U.S.A.), EndoPredict (Myriad Genetics, Salt Lake City, U.S.A.), and MammaPrint (Agendia, Irvine, CA, U.S.A.) were included in the evidence base.

CONCLUSIONS

The clinical utility of multigene profiling assays is currently established for an appropriate subset of patients with estrogen receptor-positive, her2-negative, node-negative breast cancer for whom a decision to give chemotherapy is difficult to make. For patients with estrogen receptor-positive tumours who receive tamoxifen alone, Oncotype dx, Prosigna, and EndoPredict validly identify a low-risk population with favourable outcomes, indicating that a low-risk assay result is actionable and the decision to withhold chemotherapy is supported. Clinical evidence indicates that a high Oncotype dx recurrence score can predict for chemotherapy benefit, but a high Prosigna or EndoPredict score, although prognostic, is not, based on clinical trial evidence, directly actionable. Prosigna and EndoPredict are statistically more likely to identify a population at risk for recurrence beyond 5 years, but that information is currently not actionable because of a lack of interventional studies.

Impact of 70-Gene Signature Use on Adjuvant Chemotherapy Decisions in Patients With Estrogen Receptor–Positive Early Breast Cancer: Results of a Prospective Cohort Study

Purpose

Gene-expression profiles increasingly are used in addition to conventional prognostic factors to guide adjuvant chemotherapy (CT) decisions. The Dutch guideline suggests use of validated gene-expression profiles in patients with estrogen receptor (ER) –positive, early-stage breast cancer without overt lymph node metastases. We aimed to assess the impact of a 70-gene signature (70-GS) test on CT decisions in patients with ER-positive, early-stage breast cancer.

Patients and Methods

In a prospective, observational, multicenter study in patients younger than 70 years old who had undergone surgery for ER-positive, early-stage breast cancer, physicians were asked whether they intended to administer adjuvant CT before deployment of the 70-GS test and after the test result was available.

Results

Between October 1, 2013, and December 31, 2015, 660 patients, treated in 33 hospitals, were enrolled. Fifty-one percent of patients had pT1cN0, BRII, HER2-Neu-negative breast cancer. On the basis of conventional clinicopathological characteristics, physicians recommended CT in 270 (41%) of the 660 patients and recommended withholding CT in 107 (16%) of the 660 patients. For the remaining 43% of patients, the physicians were unsure and unable to give advice before 70-GS testing. In patients for whom CT was initially recommended or not recommended, 56% and 59%, respectively, were assigned to a low-risk profile by the 70-GS (κ, 0.02; 95% CI, -0.08 to 0.11). After disclosure of the 70-GS test result, the preliminary advice was changed in 51% of patients who received a recommendation before testing; the definitive CT recommendation of the physician was in line with the 70-GS result in 96% of patients.

Conclusion

In this prospective, multicenter study in a selection of patients with ER-positive, early-stage breast cancer, 70-GS use changed the physician-intended recommendation to administer CT in half of the patients.

21-Gene recurrence score and locoregional recurrence in lymph node-negative, estrogen receptor-positive breast cancer

BACKGROUND/PURPOSE

The 21-gene recurrence score (RS) assay evaluates the likelihood of distant recurrence and benefit of chemotherapy in lymph node-negative, estrogen receptor (ER)-positive, HER2-negative breast cancer patients. The RS categories are associated with the risk of locoregional recurrence (LRR) in some, but not all studies.

METHODS

We reviewed the institutional database to identify consecutive female patients with node-negative, ER+/HER2- breast carcinoma tested for the 21-gene RS assay and treated at our center from 2008 to 2013. We collected data on clinicopathologic features, treatment, and outcome. Statistical analysis was performed using SAS version 9.4 or R version 3.3.2.

RESULTS

Of 2326 patients, 60% (1394) were in the low RS group, 33.4% (777) in the intermediate RS group, and 6.6% (155) in the high RS group. Median follow-up was 53 months. A total of 44 LRRs were observed, with a cumulative incidence of 0.17% at 12 months and 1.6% at 48 months. The cumulative incidence of LRR at 48 months was 0.84%, 2.72% and 2.80% for low, intermediate, and high RS groups, respectively (p < 0.01). Univariate analysis showed that the risk of LRR was associated with the RS categories (p < 0.01), T stage (p < 0.01) and lymphovascular invasion (LVI) (p = 0.009). There was no difference in LRR rates by initial local treatment (total mastectomy vs. breast-conserving surgery plus radiation therapy). The RS remained significantly associated with LRR after adjusting for LVI and T stage. Compared to patients with low RS, the risk of LRR was increased more than 4-fold (hazard ratio: 4.61, 95% CI 1.90-11.19, p < 0.01), and 3-fold (hazard ratio: 2.81, 95% CI 1.41-5.56, p < 0.01) for high and intermediate risk categories, respectively.

CONCLUSIONS

Our study confirms that RS is significantly associated with the risk of LRR in node-negative, ER+/HER2- breast cancer patients. Our findings suggest that in addition to its value for prognostic stage grouping and decision-making regarding adjuvant systemic therapy, the role of the RS in identifying patients not requiring radiotherapy should be studied.

The 21-gene recurrence score in special histologic subtypes of breast cancer with favorable prognosis

BACKGROUND/PURPOSE

The 21-gene recurrence score (RS) assay predicts the likelihood of distant recurrence and chemotherapy benefit in early-stage, estrogen receptor (ER)-positive, HER2-negative breast cancer. Data on the RS of special histologic subtypes of invasive breast carcinoma with favorable prognosis are limited.

METHODS

We reviewed our institutional database to identify patients with special histologic subtypes of breast cancer associated with favorable prognosis and available RS results. Our cohort consists of fifty-seven women: thirty-three patients with pure mucinous carcinoma (MC), ten with tubular carcinoma (TC), nine with encapsulated papillary carcinoma (EPC), and five with solid papillary carcinoma (SPC).

RESULTS

Most (44/57, 77.2%) carcinomas had low RS (≤17), and none had high RS (≥31). All EPCs had low RS, but other subtypes had RS 18-30. Higher RS was associated with lower progesterone receptor (PR) expression by immunohistochemistry and lower PR mRNA scores (P ≤ 0.007). No morphologic feature (tumor grade, biopsy site changes, cellular stroma, inflammatory cells) was associated with RS ≥ 18. At a median follow-up of 40 months, the distant recurrence-free survival was 100%. One patient with SPC developed locoregional recurrence at 22 months.

CONCLUSIONS

As the largest series to date, our study raises the question of whether the RS assay is necessary for breast cancers with favorable histology. Reflex testing of node-negative, ER+/HER2- breast cancers may be deferred for these special histologic subtypes, emphasizing the need for multidisciplinary discussions between breast pathologists and other members of the breast cancer team.

GENE EXPRESSION PROFILING AND EXPANDED IMMUNOHISTOCHEMISTRY TESTS TO GUIDE SELECTION OF CHEMOTHERAPY REGIMENS IN BREAST CANCER MANAGEMENT: A SYSTEMATIC REVIEW

OBJECTIVES

The aim of this report was to assess the clinical effectiveness of two Gene expression profiling (GEP) and two expanded immunohistochemistry (IHC) tests compared with current prognostic tools in guiding the use of adjuvant chemotherapy in patients with early breast cancer.

METHODS

A systematic review of the evidence on clinical effectiveness of OncotypeDX, IHC4, MammaPrint, and Mammostrat, compared with current clinical practice using clinicopathological parameters, in women with early breast cancer was conducted. Ten databases were searched to include citations to May 2016.

RESULTS

Searches identified 7,064 citations, of which forty-one citations satisfied the criteria for the review. A narrative synthesis was performed. Evidence for OncotypeDX demonstrated the impact of the test on decision making and there was some support for OncotypeDX predicting chemotherapy benefit. There were relatively lower levels of evidence for the other three tests included in the analysis. MammaPrint, Mammostrat, and IHC4 tests were limited to a small number of studies. Limitations in relation to study design were identified for all tests.

CONCLUSIONS

The evidence base for OncotypeDX is considered to be the most robust. Methodological weaknesses relating to heterogeneity of patient cohorts and issues arising from the retrospective nature of the evidence were identified. Further evidence is required for all of the tests using prospective randomized controlled trial data.

Multigene expression profile testing in breast cancer: is there a role for family physicians?

BACKGROUND

Family physicians (fps) play a role in aspects of personalized medicine in cancer, including assessment of increased risk because of family history. Little is known about the potential role of fps in supporting cancer patients who undergo tumour gene expression profile (gep) testing.

METHODS

We conducted a mixed-methods study with qualitative and quantitative components. Qualitative data from focus groups and interviews with fps and cancer specialists about the role of fps in breast cancer gep testing were obtained during studies conducted within the pan-Canadian canimpact research program. We determined the number of visits by breast cancer patients to a fp between the first medical oncology visit and the start of chemotherapy, a period when patients might be considering results of gep testing.

RESULTS

The fps and cancer specialists felt that ordering gep tests and explaining the results was the role of the oncologist. A new fp role was identified relating to the fp-patient relationship: supporting patients in making adjuvant therapy decisions informed by gep tests by considering the patient's comorbid conditions, social situation, and preferences. Lack of fp knowledge and resources, and challenges in fp-oncologist communication were seen as significant barriers to that role. Between 28% and 38% of patients visited a fp between the first oncology visit and the start of chemotherapy.

CONCLUSIONS

Our findings suggest an emerging role for fps in supporting patients who are making adjuvant treatment decisions after receiving the results of gep testing. For success in this new role, education and point-of-care tools, together with more effective communication strategies between fps and oncologists, are needed.

Adjuvant treatment recommendations for patients with ER-positive/HER2-negative early breast cancer by Swiss tumor boards using the 21-gene recurrence score (SAKK 26/10)

Background

To evaluate the effect of Recurrence Score® results (RS; Oncotype DX® multigene assay ODX) on treatment recommendations by Swiss multidisciplinary tumor boards (TB).

Methods

SAKK 26/10 is a multicenter, prospective cohort study of early breast cancer patients: Eligibility: R0-resection, ≥10% ER+ malignant cells, HER2–, pN0/pN1a. Patients were stratified into low-risk (LR) and non-low-risk (NLR) groups based on involved nodes (0 vs 1–3) and five additional predefined risk factors. Recommendations were classified as hormonal therapy (HT) or chemotherapy plus HT (CT + HT). Investigators were blinded to the statistical analysis plan. A 5%/10% rate of recommendation change in LR/NLR groups, respectively, was assumed independently of RS (null hypotheses).

Results

Two hundred twenty two evaluable patients from 18 centers had TB recommendations before and after consideration of the RS result. A recommendation change occurred in 45 patients (23/154 (15%, 95% CI 10–22%) in the LR group and 22/68 (32%, 95% CI 22–45%) in the NLR group). In both groups the null hypothesis could be rejected (both p < 0.001). Specifically, in the LR group, only 5/113 (4%, 95% CI 1–10%) with HT had a recommendation change to CT + HT after consideration of the RS, while 18/41 (44%, 95% CI 28–60%) of patients initially recommended CT + HT were subsequently recommended only HT. In the NLR group, 3/19 (16%, 95% CI 3–40%) patients were changed from HT to CT + HT, while 19/48 (40%, 95% CI 26–55%) were changed from CT + HT to HT.

Conclusion

There was a significant impact of using the RS in the LR and the NLR group but only 4% of LR patients initially considered for HT had a recommendation change (RC); therefore these patients could forgo ODX testing. A RC was more likely for NLR patients considered for HT. Patients considered for HT + CT have the highest likelihood of a RC based on RS.

Uptake of a 21-gene expression assay in breast cancer practice: views of academic and community-based oncologists

PURPOSE

Advances in personalized medicine have produced novel tests and treatment options for women with breast cancer. Relatively little is known about the process by which such tests are adopted into oncology practice. The objectives of the present study were to understand the experiences of medical oncologists with multigene expression profile (gep) tests, including their adoption into practice in early-stage breast cancer, and the perceptions of the oncologists about the influence of test results on treatment decision-making.

METHODS

We conducted a qualitative descriptive study involving interviews with medical oncologists from academic and community cancer centres or hospitals in 8 communities in Ontario. A 21-gene breast cancer assay was used as the example of gep testing. Qualitative analytic techniques were used to identify the main themes.

RESULTS

Of 28 oncologists who were approached, 21 (75%) participated in the study [median age: 43 years; 12 women (57%)]. Awareness and knowledge of gep testing were derived from several sources: international scientific meetings, participation in clinical studies, discussions with respected colleagues, and manufacturer-sponsored meetings. Oncologists observed that incorporating gep testing into their clinical practice resulted in several changes, including longer consultation times, second visits, and taking steps to minimize treatment delays. Oncologists expressed divergent opinions about the strength of evidence and added value of gep testing in guiding treatment decisions.

CONCLUSIONS

Incorporation of gep testing into clinical practice in early-stage breast cancer required oncologists to make changes to their usual routines. The opinions of oncologists about the quality of evidence underpinning the test affected how much weight they gave to test results in treatment decision-making.

The influence of 21-gene recurrence score assay on chemotherapy use in a population-based sample of breast cancer patients

PURPOSE

To quantify the influence of RS assay on changing chemotherapy plans in a general practice setting using causal inference methods.

METHODS

We surveyed 3880 newly diagnosed breast cancer patients in Los Angeles and Georgia in 2013-14. We used inverse propensity weighting and multiple imputations to derive complete information for each patient about treatment status with and without testing.

RESULTS

A half of the 1545 women eligible for testing (ER+ or PR+, HER2-, and stage I-II) received RS. We estimate that 30% (95% confidence interval (CI) 10-49%) of patients would have changed their treatment selections after RS assay, with 10% (CI 0-20%) being encouraged to undergo chemotherapy and 20% (CI 10-30%) being discouraged from chemotherapy. The subgroups whose treatment selections would be changed the most by RS were patients with positive nodes (44%; CI 24-64%), larger tumor (43% for tumor size >2 cm; CI 23-62%), or younger age (41% for <50 years, CI 23-58%). The assay was associated with a net reduction in chemotherapy use by 10% (CI 4-16%). The reduction was much greater for women with positive nodes (31%; CI 21-41%), larger tumor (30% for tumor size >2 cm; CI 22-38%), or younger age (22% for <50 years; CI 9-35%).

CONCLUSION

RS substantially changed chemotherapy treatment selections with the largest influence among patients with less favorable pre-test prognosis. Whether this is optimal awaits the results of clinical trials addressing the utility of RS testing in selected subgroups.