Adoption of gene expression profile testing and association with use of chemotherapy among women with breast cancer

The Utility of the Oncotype DX Test for Breast Cancer Patients in an Australian Multidisciplinary Setting

Introduction

The Oncotype DX test is a genomic assay that generates a Recurrence Score (RS) predicting the 10-year risk of recurrence and response to adjuvant chemotherapy in ER+/HER2− breast cancer patients. The aims were to determine breast cancer distant recurrence and correlate with adjuvant chemoendocrine prescribing patterns based on the Oncotype DX recurrence score.

Methods

We conducted a retrospective single-institution case series of 71 patients who had Oncotype DX assay testing after definitive surgery between 2012 and 2016. Both node-positive and node-negative patients were included. Patients were divided into Oncotype DX low risk (RS < 11) (n = 10, 14%), intermediate risk (RS 11–25) (n = 45, 63%), and high risk (RS > 25) (n = 16, 23%). Median follow-up was 6.1 years (range 4–8.9 years). Adjuvant treatment regimens and oncological outcomes were determined. Results. Mean age at diagnosis was 56 years (range, 33–77). Invasive ductal carcinoma (IDC) accounted for the majority (87%), with most tumors measuring between 10–20 mm (52%). 48% of the cohort were node positive. 15 of 16 high-risk patients (94%) received chemotherapy. 96% of intermediate-risk patients received endocrine therapy alone, one patient received chemoendocrine therapy (2%), and one declined systemic therapy (2%). In the low-risk group, 100% received endocrine therapy only. The high-risk group had the lowest mean ER% (P < 0.05), greatest mean mitotic rate (P < 0.05), and greatest proportion of Ki67% > 14. Five patients developed distant recurrence (7%): three from the intermediate-risk group (7%), one from the low-risk group (10%), and one from the high-risk group (6%).

Conclusion

This is the first Australian study reporting the experience with medium-term recurrence outcomes of using the Oncotype DX assay in breast cancer. Chemotherapy was rarely given for patients with low-to-intermediate RS and always offered in high RS. This pattern of prescribing was associated with low rates of distant recurrence. National funding models should be considered.

Application of the 21-Gene Recurrence Score in Patients with Early HR-Positive/HER2-Negative Breast Cancer: Chemotherapy and Survival Rate According to Clinical Risk

Simple Summary

It is important to address the influence of 21-gene Recurrence Score (RS) on chemotherapy decision-making stratified by clinical risk in patients with hormone receptor (HR)-positive/human epidermal growth factor receptor 2 (HER2)-negative early breast cancer. Our study presented that the application of the 21-gene RS assay significantly reduced the chemotherapy rate in patients with high clinical risk. Meanwhile, there was no significant difference in the chemotherapy rate according to the implementation of the 21-gene RS assay in those with low clinical risk. Furthermore, we observed no difference in prognosis according to the application of 21-gene RS for either clinical risk. These results suggest that the 21-gene RS could be considered more positively in HR+/HER2- patients with high clinical risk to reduce chemotherapy rates without increasing the occurrence of relapse.

Abstract

We assessed the impact of 21-gene Recurrence Score (RS) assay on chemotherapy decision-making according to binary clinical risk stratification in patients with hormone receptor (HR)-positive/human epidermal growth factor receptor 2 (HER2)-negative early breast cancer. We included patients with tumors measuring 1–5 cm, N0-1, and HR+/HER2- breast cancer who underwent surgery followed by adjuvant treatment. The clinical risk was determined by a modified version of Adjuvant! Online. We performed propensity score matching (PSM) according to the application of 21-gene RS separately in the low and high clinical risk groups. Before PSM, 342 (39.0%) of 878 patients were classified as having high clinical risk. In the high clinical risk group, 21-gene RS showed a significantly reduced chemotherapy rate of 39.3%, without increasing the recurrence. After PSM, the 21-gene RS application significantly reduced chemotherapy rate by 34.0% in 200 patients with high clinical risk (21-gene RS application, 32.0% vs. no 21-gene RS application, 66.0%, p < 0.001). There was also no significant difference in RFS according to 21-gene RS status in the high clinical risk group (log-rank test, p = 0.467). These results support the usefulness of the 21-gene RS to reduce the chemotherapy rate without adversely affecting prognosis in a high clinical risk group.

Current developments in delivering customized care: a scoping review

BACKGROUND

In recent years, there has been a growing interest in health care personalization and customization (i.e. personalized medicine and patient-centered care). While some positive impacts of these approaches have been reported, there has been a dearth of research on how these approaches are implemented and combined for health care delivery systems. The present study undertakes a scoping review of articles on customized care to describe which patient characteristics are used for segmenting care, and to identify the challenges face to implement customized intervention in routine care.

METHODS

Article searches were initially conducted in November 2018, and updated in January 2019 and March 2019, according to Prisma guidelines. Two investigators independently searched MEDLINE, PubMed, PsycINFO, Web of Science, Science Direct and JSTOR, The search was focused on articles that included "care customization", "personalized service and health care", individualized care" and "targeting population" in the title or abstract. Inclusion and exclusion criteria were defined. Disagreements on study selection and data extraction were resolved by consensus and discussion between two reviewers.

RESULTS

We identified 70 articles published between 2008 and 2019. Most of the articles (n = 43) were published from 2016 to 2019. Four categories of patient characteristics used for segmentation analysis emerged: clinical, psychosocial, service and costs. We observed these characteristics often coexisted with the most commonly described combinations, namely clinical, psychosocial and service. A small number of articles (n = 18) reported assessments on quality of care, experiences and costs. Finally, few articles (n = 6) formally defined a conceptual basis related to mass customization, whereas only half of articles used existing theories to guide their analysis or interpretation.

CONCLUSIONS

There is no common theory based strategy for providing customized care. In response, we have highlighted three areas for researchers and managers to advance the customization in health care delivery systems: better define the content of the segmentation analysis and the intervention steps, demonstrate its added value, in particular its economic viability, and align the logics of action that underpin current efforts of customization. These steps would allow them to use customization to reduce costs and improve quality of care.

Breast cancer in the oldest old (≥ 89 years): Tumor characteristics, treatment choices, clinical outcomes and literature review

INTRODUCTION

Risk of breast cancer increases with age and very few data are available in patients older than 89.

METHODS

A retrospective analysis on patients aged 89 and older treated between 2008 and 2019 at our certified breast center. The aim was to analyze clinical characteristics, decision-making, treatment, outcomes and open questions regarding this subpopulation for which there is a lack of guidelines.

RESULTS

58 patients included. Tumor characteristics were analyzed, 85% patients underwent surgery of which 44% had a mastectomy. The median follow-up and overall survival were 20 and 76 months, respectively.The median survival of metastatic and non-metastatic patients were 14 and 50 months, respectively. Most patients did not receive any adjuvant treatment and among these 14% had a relapse.

CONCLUSIONS

Elderly patients should not be under or over-treated because of their age; they represent a large heterogeneous group deserving a sub-stratification for a better tailored treatment.

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.

Chemotherapy Costs and 21-Gene Recurrence Score Genomic Testing Among Medicare Beneficiaries With Early-Stage Breast Cancer, 2005 to 2011

BACKGROUND

This study examined whether associations between 21-gene recurrence score (RS) genomic testing and lower costs among patients with early-stage, estrogen receptor-positive breast cancer are observable in real-world data from the Medicare population.

METHODS

A retrospective cohort study was conducted using SEER-Medicare data for a nationally representative sample of Medicare beneficiaries diagnosed from 2005 through 2011. The main outcomes were associations between RS testing and overall and chemotherapy-specific costs. The primary analysis was restricted to patients aged 66 to 75 years.

RESULTS

The primary analysis comprised 30,058 patients. Mean costs 1 year after diagnosis were $35,940 [SD, $28,894] overall, $51,127 [33,386] for clinically high-risk disease, $33,225 [$27,711] for intermediate-risk disease, and $26,695 [$19,532] for low-risk disease. Chemotherapy-specific costs followed similar trends. In multivariable analyses, RS testing was associated with significantly lower costs among high-risk patients in terms of both relative costs (cost ratio, 0.88; 99% CI, 0.82-0.94) and absolute costs ($6,606; 99% CI, $39,223-$9,290). Higher costs among low-risk and intermediate-risk patients were mainly caused by higher noncancer costs. In sensitivity analyses that included all patients aged ≥66 years (N=64,996), associations between RS testing and costs among high-risk patients were similar but less pronounced because of lower overall use of chemotherapy.

CONCLUSIONS

RS testing was associated with lower overall and chemotherapy-related costs in patients with high-risk disease, consistent with lower chemotherapy use among these patients. Higher overall costs for patients with intermediate-risk and low-risk disease were driven largely by non-treatment-related costs.

Cost-effectiveness analyses demonstrate that observation is superior to sentinel lymph node biopsy for postmenopausal women with HR + breast cancer and negative axillary ultrasound

PURPOSE

To evaluate the cost-effectiveness of axillary observation versus sentinel lymph node biopsy (SLNB) after negative axillary ultrasound (AUS). In patients with clinical T1-T2 N0 breast cancer and negative AUS, SLNB is the current standard of care for axillary staging. However, SLNB is costly, invasive, decreasing in importance for medical decision-making, and is not considered therapeutic. Observation alone is currently being evaluated in randomized clinical trials, and is thought to be non-inferior to SLNB for patients with negative AUS.

METHODS

We performed cost-effectiveness analyses of observation versus SLNB after negative AUS in postmenopausal women with clinical T1-T2 N0, HR⁺/HER2^- breast cancer. Costs at the 2016 price level were evaluated from a third-party commercial payer perspective using the MarketScan® Database. We compared cost, quality-adjusted life years (QALYs), and net monetary benefit (NMB). Multiple sensitivity analyses varying baseline probabilities, costs, utilities, and willingness-to-pay thresholds were performed.

RESULTS

Observation was superior to SLNB for patients with N0 and N1 disease, and for the entire patient population (NMB in US$: $655,659 for observation versus $641,778 for SLNB for the entire patient population). In the N0 and N1 groups, observation incurred lower cost and was associated with greater QALYs. SLNB was superior for patients with > 3 positive lymph nodes, representing approximately 5% of the population. Sensitivity analyses consistently demonstrated that observation is the optimal strategy for AUS-negative patients.

CONCLUSION

Considering both cost and effectiveness, observation is superior to SLNB in postmenopausal women with cT1-T2 N0, HR⁺/HER2^- breast cancer and negative AUS.

Trend and survival benefit of Oncotype DX use among female hormone receptor-positive breast cancer patients in 17 SEER registries, 2004-2015

PURPOSE

To examine (1) the trend and associated factors of Oncotype DX (ODX) use among hormone receptor-positive (HR+) breast cancer (BC) patients in 2004-2015; (2) the trend of reported chemotherapy by Recurrence Score (RS); and (3) the survival differences associated with ODX use.

METHODS

ODX data from Genomic Health Inc. were linked with 17 SEER registries data. HR + BC cases with lymph node negative (N0) or 1-3 positive LNs (N1) from 2004-2015 were analyzed. The Cochrane-Armitage trend test, logistic regression, Kaplan-Meier survival curve, and stratified Cox model were performed. Survival analysis was restricted to HR+/HER2- patients from 2010 to 2014, matched on propensity score.

RESULTS

ODX use increased substantially from 2004 to 2015 (N0: 2.0% to 42.7%; N1: 0.3% to 27.9%). Non-Hispanic black and Medicaid insured patients had lower odds of receiving ODX. N0 patients with moderately differentiated or 2.1-5.0 cm tumor and N1 patients with well-differentiated or < 2.0 cm tumor had higher odds of using ODX. The reported chemotherapy use decreased significantly with low and intermediate RS, and increased for high RS among N0 patients. ODX use was associated with better breast cancer-specific survival [hazard ratio (95% CI) N0 1.96 (1.60-2.41), N1 1.90 (1.42-2.54)] and overall survival [N0 2.06 (1.83-2.31), N1 1.72 (1.42-2.09)], especially in the first 36 months.

CONCLUSION

ODX use has increased significantly since 2004, nonetheless disparities remain, especially for racial/ethnic minorities and Medicaid insured patients. Administering chemotherapy based on ODX results has been improved among N0 patients. Patients receiving ODX had better survival than those not.

Prognostic Impact of the 21-Gene Recurrence Score Assay Among Young Women With Node-Negative and Node-Positive ER-Positive/HER2-Negative Breast Cancer

PURPOSE

The 21-gene recurrence score (RS) assay is prognostic among women with early-stage estrogen receptor-positive (ER+) and human epidermal growth factor receptor 2-negative (HER2-) breast cancer and is used to inform recommendations for chemotherapy. Women ≤ 40 years of age represent a minority of patients studied using gene expression profiles.

METHODS

The Young Women's Breast Cancer Study is a prospective cohort of women diagnosed with breast cancer at age ≤ 40 years and enrolled patients between 2006 and 2016 (N = 1,302). We identified patients with stage I-III ER+/HER2- breast cancer. The RS assay was performed on banked specimens for patients who had not been tested clinically. Distant recurrence-free survival (DRFS) was assessed by TAILORx and traditional RS risk groups among patients with axillary node-negative (N0) and limited node-positive (N1) breast cancer.

RESULTS

Among eligible women (N = 577), 189 (33%) had undergone RS testing, and 320 (56%) had banked specimens sufficient for testing. Median follow-up was 6.0 years. Median age at diagnosis was 37.2 years; 300 of 509 patients (59%) had N0 breast cancer, of whom 195 (65%) had an RS of 11-25 and fewer than half (86 of 195; 44%) received chemotherapy. Six-year DRFS rates were 94.4% and 92.3% (RS < 11), 96.9% and 85.2% (RS 11-25), and 85.1% and 71.3% (RS ≥ 26) among women with N0 and N1 disease, respectively.

CONCLUSION

The RS assay is prognostic among young women with node-negative and limited node-positive breast cancer, representing a valuable tool for risk stratification. Disease outcomes with a median follow-up of 6 years among young women with N0 disease and an RS of 0-25, a minority of whom received chemotherapy, and node-positive disease with an RS < 11 were very good, whereas those with N0 disease and an RS ≥ 26 or N1 disease with an RS ≥ 11 experienced substantial risk of early distant recurrence.

A Value of Information Analysis of Research on the 21-Gene Assay for Breast Cancer Management

OBJECTIVES

The 21-gene assay Oncotype DX (21-GA) shows promise as a guide in deciding when to initiate adjuvant chemotherapy in women with hormone receptor-positive early-stage breast cancer. Nevertheless, its routine use remains controversial, owing to insufficient evidence of its clinical utility and cost-effectiveness. Accordingly, we aim to quantify the value of conducting further research to reduce decision uncertainty in the use of the 21-GA.

METHODS

Using value of information methods, we first generated probability distributions of survival and costs for decision making with and without the 21-GA alongside traditional risk prediction. These served as the input to a comparison of 3 alternative study designs: a retrospective observational study to update risk classification from the 21-GA, a prospective observational study to estimate prevalence of chemotherapy use, and a randomized controlled trial (RCT) of the 21-GA predictive value.

RESULTS

We found that current evidence strongly supports the use of the 21-GA in intermediate- and high-risk women. Further research should focus on low-risk women, among whom the cost-effectiveness findings remained equivocal. For this population, we identified a high value of reducing uncertainty in the 21-GA use for all proposed research studies. The RCT had the greatest potential to efficiently reduce the likelihood of choosing a suboptimal strategy, providing a value between $162 million and $1.1 billion at willingness-to-pay thresholds of $150 000 to $200 000/quality-adjusted life years.

CONCLUSION

Future research to inform 21-GA decision making is of high value. The RCT of the 21-GA predictive value has the greatest potential to efficiently reduce decision uncertainty around 21-GA use in women with low-risk early-stage breast cancer.

The Changing Role of Gene-Expression Profiling in the Era of De-escalating Adjuvant Chemotherapy in Early-Stage Breast Cancer

PURPOSE

We assessed the recent trends in the administration of adjuvant chemotherapy thereby evaluating the role of the 70-gene signature (70-GS) testing in decision-making in the systemic treatment of patients with lymph node negative (N0) and lymph node positive (N+) breast cancer.

METHODS

Patients with a national guideline directed indication for 70-GS use treated between 2013 and 2016 were selected from the Netherlands Cancer Registry. Time trends in the administration of adjuvant chemotherapy were evaluated within guideline- and age-delineated subgroups. The influence of the 70-GS on chemotherapy use was assessed with logistic regression.

RESULTS

During the study period, the overall administration of adjuvant chemotherapy decreased from 49 to 23% and 70-GS use increased from 24 to 51%. The 70-GS was not associated with a decreased likelihood for N0 patients to receive chemotherapy (odds ratio [OR] 1.0; 95% confidence interval [CI] 0.86-1.17), as the proportion of N0 patients who received chemotherapy in the absence of 70-GS use decreased during the study period. In patients with N1a disease, 70-GS testing was associated with a decreased likelihood to receive chemotherapy (OR 0.21; 95% CI 0.15-0.29). In patients < 50 years and 50-59 years of age, 70-GS use was associated with a consistent lower proportion of patients receiving chemotherapy throughout the study period (OR 0.17; 95% CI 0.13-0.23 and OR 0.53; 95% CI 0.43-0.65, respectively).

CONCLUSIONS

In this population-based study, the administration of adjuvant chemotherapy in ER+ breast cancer strongly declined. For node-positive and younger patients, 70-GS use was associated with a decreased probability for patients to receive adjuvant chemotherapy.

Multigene expression signatures in early hormone receptor positive HER 2 negative breast cancer

Background The standard treatment of hormone receptor positive, HER2 negative early breast cancer (BC) is surgery followed by adjuvant systemic therapy either with endocrine therapy alone or with the addition of chemotherapy followed by endocrine therapy. Adjuvant systemic therapy reduces the risk of recurrence and death from BC. Whether an individual patient will benefit from adjuvant chemotherapy is an important clinical decision. Decisions that rely solely on clinical-pathological factors can often lead to overtreatment. Multigene signatures represent an important progress in optimal selection of high risk patients that might benefit from the addition of chemotherapy to adjuvant endocrine therapy. Conclusions Several signatures are already commercially available and also accepted by international guidelines. Oncotype DX and MammaPrint have been most extensively validated and supported by level IA evidence.

Race and delays in breast cancer treatment across the care continuum in the Carolina Breast Cancer Study

BACKGROUND

After controlling for baseline disease factors, researchers have found that black women have worse breast cancer survival, and this suggests that treatment differences may contribute to poorer outcomes. Delays in initiating and completing treatment are one proposed mechanism.

METHODS

Phase 3 of the Carolina Breast Cancer Study involved a large, population-based cohort of women with incident breast cancer. For this analysis, we included black women (n = 1328) and white women (n = 1331) with stage I to III disease whose treatment included surgery with or without adjuvant therapies. A novel treatment pathway grouping was used to benchmark the treatment duration (surgery only, surgery plus chemotherapy, surgery plus radiation, or all 3). Models controlled for the treatment pathway, age, and tumor characteristics and for demographic factors related to health care access. Exploratory analyses of the association between delays and cancer recurrence were performed.

RESULTS

In fully adjusted analyses, blacks had 1.73 times higher odds of treatment initiation more than 60 days after their diagnosis in comparison with whites (odds ratio [OR], 1.73; 95% confidence interval [CI], 1.04-2.90). Black race was also associated with a longer treatment duration. Blacks were also more likely to be in the highest quartile of treatment duration (OR, 1.69; 95% CI, 1.41-2.02), even after adjustments for demographic and tumor characteristics (OR, 1.31; 95% CI, 1.04-1.64). A nonsignificant trend toward a higher recurrence risk was observed for patients with delayed initiation (hazard ratio, 1.44; 95% CI, 0.89-2.33) or the longest duration (hazard ratio, 1.17; 95% CI, 0.87-1.59).

CONCLUSIONS

Black women more often had delayed treatment initiation and a longer duration than whites receiving similar treatment. Interventions that target access barriers may be needed to improve timely delivery of care.

Diffusion-weighted MRI of estrogen receptor-positive, HER2-negative, node-negative breast cancer: association between intratumoral heterogeneity and recurrence risk

OBJECTIVES

To investigate possible associations between quantitative apparent diffusion coefficient (ADC) metrics derived from whole-lesion histogram analysis and breast cancer recurrence risk in women with estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-negative, node-negative breast cancer who underwent the Oncotype DX assay.

METHODS

This retrospective study was conducted on 105 women (median age, 48 years) with ER-positive, HER2-negative, node-negative breast cancer who underwent the Oncotype DX test and preoperative diffusion-weighted imaging (DWI). Histogram analysis of pixel-based ADC data of whole tumors was performed, and various ADC histogram parameters (mean, 5th, 25th, 50th, 75th, and 95th percentiles of ADCs) were extracted. The ADC difference value (defined as the difference between the 5th and 95th percentiles of ADCs) was calculated to assess intratumoral heterogeneity. Associations between quantitative ADC metrics and the recurrence risk, stratified using the Oncotype DX recurrence score (RS), were evaluated.

RESULTS

Whole-lesion histogram analysis showed that the ADC difference value was different between the low-risk recurrence (RS < 18) and the non-low-risk recurrence (RS ≥ 18; intermediate to high risk of recurrence) groups (0.600 × 10^-3 mm²/s vs. 0.746 × 10^-3 mm²/s, p < 0.001). Multivariate regression analysis demonstrated that a lower ADC difference value (< 0.559 × 10^-3 mm²/s; odds ratio [OR] = 5.998; p = 0.007) and a small tumor size (≤ 2 cm; OR = 3.866; p = 0.012) were associated with a low risk of recurrence after adjusting for clinicopathological factors.

CONCLUSIONS

The ADC difference value derived from whole-lesion histogram analysis might serve as a quantitative DWI biomarker of the recurrence risk in women with ER-positive, HER2-negative, node-negative invasive breast cancer.

KEY POINTS

• A lower ADC difference value and a small tumor size were associated with a low risk of recurrence of breast cancer. • The ADC difference value could be a quantitative marker for intratumoral heterogeneity. • Whole-lesion histogram analysis of the ADC could be helpful for discriminating the low-risk from non-low-risk recurrence groups.

Impact of Genomic Assay Testing and Clinical Factors on Chemotherapy Use After Implementation of Standardized Testing Criteria

BACKGROUND

For clinically appropriate early-stage breast cancer patients, reflex criteria for Oncotype DX ordering ("the intervention") were implemented at our comprehensive cancer center, which reduced time-to-adjuvant chemotherapy initiation. Our objective was to evaluate Oncotype DX ordering practices and chemotherapy use before and after implementation of the intervention.

MATERIALS AND METHODS

We examined medical records for 498 patients who had definitive breast cancer surgery at our center. The post-intervention cohort consisted of 232 consecutive patients who had Oncotype DX testing after reflex criteria implementation. This group was compared to a retrospective cohort of 266 patients who were diagnosed and treated prior to reflex criteria implementation, including patients who did and did not have Oncotype DX ordered. Factors associated with Oncotype DX ordering pre- and post-intervention were examined. We used multivariate logistic regression to evaluate factors associated with chemotherapy receipt among patients with Oncotype DX testing.

RESULTS

The distribution of Oncotype DX scores, the proportion of those having Oncotype DX testing (28.9% vs. 34.1%) and those receiving chemotherapy (14.3% vs. 19.4%), did not significantly change between pre- and post-intervention groups. Age ≤65 years, stage II, grade 2, 1-3+ nodes, and tumor size >2 cm were associated with higher odds of Oncotype DX testing. Among patients having Oncotype DX testing, node status and Oncotype DX scores were significantly associated with chemotherapy receipt.

CONCLUSION

Our criteria for reflex Oncotype DX ordering appropriately targeted patients for whom Oncotype DX would typically be ordered by providers. No significant change in the rate of Oncotype DX ordering or chemotherapy use was observed after reflex testing implementation.

IMPLICATIONS FOR PRACTICE

This study demonstrates that implementing multidisciplinary consensus reflex criteria for Oncotype DX ordering maintains a stable Oncotype DX ordering rate and chemotherapy rate, mirroring what was observed in a specific clinical practice, while decreasing treatment delays due to additional testing. These reflex criteria appropriately capture patients who would likely have had Oncotype DX ordered by their providers and for whom the test results are predicted to influence management. This intervention serves as a potential model for other large integrated, multidisciplinary oncology centers to institute processes targeting patient populations most likely to benefit from genomic assay testing, while mitigating treatment delays.

Does integration of Magee equations into routine clinical practice affect whether oncologists order the Oncotype DX test? A prospective randomized trial

OBJECTIVE

The three Magee Equations provide an estimate of the Oncotype DX recurrence score using commonly available clinicopathologic information (tumour size, grade, oestrogen receptor, progesterone receptor, HER2, and Ki67). We assessed whether integration of Magee Equations into routine clinical practice affected the frequency of Oncotype DX requests.

METHODS

Patients with newly diagnosed, node negative, hormone receptor positive, and HER2 negative invasive breast cancer were randomized to undergo a Magee calculation or not. At the first clinic assessment, the oncologist was provided with all routinely available clinicopathologic information (including Ki67) either with or without the results of Magee Equations. Primary outcome was frequency of Oncotype DX ordering. Secondary outcomes included frequency of chemotherapy use, time to commencement of radiotherapy, or systemic therapy. Physician comfort with systemic therapy choices and the use of Ki67 and Magee Equations was also assessed.

RESULTS

Data from 175 randomized patients was available, 84 patients (48%) with and 91 (52%) without calculated Magee Equations. Oncotype DX was ordered in 10 (12.05%) and 13 (14.44%) (RR 0.83, 0.39-1.80; P = 0.64) in the Magee and no Magee groups, respectively. There were no statistically or clinically significant differences between the randomized groups for any of the secondary outcomes. Availability of both Ki67 and Magee Equations was associated with increased physician comfort around systemic treatment decisions.

CONCLUSIONS

In a practice where Ki67 is routinely available, addition of Magee Equations into routine clinic practice was not associated with a reduction in Oncotype DX use. Availability of both Ki67 and Magee Equations did however increase physician comfort with systemic therapy decisions.

Multi-gene assays: effect on chemotherapy use, toxicity and cost in estrogen receptor-positive early stage breast cancer

Aim: To assess multi-gene assay (MGA) effects on chemotherapy use, toxicities, recurrences, and costs in estrogen receptor-positive early breast cancer. Methods: Meta-analysis performed using data from public databases. Results: Studies included 12,202 women. Relative to no testing, chemotherapy use was higher with 12-gene and 70-gene and lower with PAM50 (commercial) and 21-gene MGAs. Overall, 1643 distant recurrences occurred with no testing, declining by 231 (21-gene), 121 (70-gene), 54 (12-gene) and 94 (PAM50); only the 21-gene assay resulted in no risk of increasing the number of distant recurrences. Relative to ‘no testing’, total cost of care declined only with 21-gene MGA. Conclusion: MGAs differ in chemotherapy use and related outcomes for women with estrogen receptor-positive early breast cancer.

Factors Determining Anthracycline Use in Hormone Receptor Positive, Early-Stage Breast Cancer

BACKGROUND

Anthracyclines are associated with significant toxicities whereas nonanthracyclines have proven to be better tolerated. A 21-gene assay allows clinicians to predict who will not benefit from adjuvant chemotherapy and avoid systemic toxicities. Physicians are using the recurrence score to guide chemotherapy selection, despite the lack of evidence. In this study we examined factors associated with prescribing patterns for an anthracycline-based chemotherapy in hormone receptor-positive stage I to III breast cancer.

MATERIALS AND METHODS

This was a retrospective study using the Michigan Breast Oncology Quality Initiative data set (February 1, 2006 to December 31, 2015). Women with histologically confirmed stage I to III invasive breast cancer with estrogen receptor and/or progesterone receptor-positive, HER2/neu-negative receptor status were included. We used χ² analysis to determine associations of these characteristics with the 21-gene assay score and anthracycline use.

RESULTS

A total of 17,788 patients were evaluated. Most tumors were stage I (60%). Most procedures were lumpectomy with radiation (66%). Anthracyclines were used more often in stage III patients (69%), younger patients (40% for patients younger than 65 years), and those with higher 21-gene recurrence scores. Patients with low recurrence scores were more likely to receive anthracyclines if lymph node-positive (10%) than if lymph node-negative (1%; P < .001). Patients with high recurrence scores and lymph node-positive status were just as likely to receive an anthracycline-based as a nonanthracycline-based regimen (47.5% vs. 49.2%; P = .89).

CONCLUSION

These data indicate that medical oncologists might be anticipating the results of Adjuvant Chemotherapy Guided by a 21-Gene Expression Assay in Breast Cancer study (TAILORx) and the Clinical Outcomes in ER+HER2-node-positive Breast Cancer Patients Who Were Treated According to the Recurrence Score Results: Evidence From a Large Prospectively Designed Registry (RxPonder) trials and are avoiding the potential serious complications associated with anthracycline treatment in patients least likely to receive benefit.

The impact of gene expression profile testing on confidence in chemotherapy decisions and prognostic expectations

PURPOSE

Little is known about whether gene expression profile (GEP) testing and specific recurrence scores (e.g., medium risk) improve women's confidence in their chemotherapy decision or perceived recurrence risk. We evaluate the relationship between these outcomes and GEP testing.

METHODS

We surveyed women eligible for GEP testing (stage I or II, Gr1-2, ER+, HER2-) identified through the Surveillance, Epidemiology, and End Results (SEER) Registry of Washington or Kaiser Permanente Northern California from 2012 to 2016, approximately 0-4 years from diagnosis (N = 904, RR = 45.4%). Confidence in chemotherapy was measured as confident (Very, completely) versus Not Confident (Somewhat, A little, Not At All); perceived risk recurrence was recorded numerically (0-100%). Women reported their GEP test receipt (Yes, No, Unknown) and risk recurrence score (High, Intermediate, Low, Unknown). In our analytic sample (N = 833), we propensity score weighted the three test receipt cohorts and used propensity weighted multivariable regressions to examine associations between the outcomes and the three test receipt cohorts, with receipt stratified by score.

RESULTS

29.5% reported an unknown GEP test receipt; 86% being confident. Compared to no test receipt, an intermediate score (aOR 0.34; 95% CI 0.20-0.58), unknown score (aOR 0.09; 95% CI 0.05-0.18), and unknown test receipt (aOR 0.37; 95% CI 0.24-0.57) were less likely to report confidence. Most women greatly overestimated their recurrence risk regardless of their test receipt or score.

CONCLUSIONS

GEP testing was not associated with greater confidence in chemotherapy decisions. Better communication about GEP testing and the implications for recurrence risk may improve women's decisional confidence.

Lymph Node Status in Breast Cancer Does Not Predict Tumor Biology

BACKGROUND/OBJECTIVE

The 21-gene Oncotype DX® Breast Recurrence Score® (RS) assay has been prospectively validated as prognostic and predictive in node-negative, estrogen receptor-positive (ER+)/HER2- breast cancer patients. Less is known about its prognostic role in node-positive breast cancer. We compared RS results among patients with lymph node-negative (N0), micrometastatic (N1mi), and macrometastatic (N+) breast cancer to determine if nodal metastases are associated with more aggressive biology, as determined by RS.

METHODS

Overall, 610,350 tumor specimens examined by the Genomic Health laboratory from February 2004 to August 2017 were studied. Histology was classified centrally, while lymph node status was determined locally. RS distribution (low: < 18; intermediate: 18-30; high: ≥ 31) was compared by nodal status.

RESULTS

Eighty percent (n = 486,013) of patients were N0, 4% (n = 24,325) were N1mi, 9% (n = 56,100) were N+, and 7% (n = 43,912) had unknown nodal status. Mean RS result was 18, 16.7, 17.3 and 18.9 in the N0, N1mi, N+, and unknown groups, respectively. An RS ≥ 31 was seen in 10% of N0 patients, 7% of N1mi patients, and 8.0% of N+ patients. The likelihood of an RS ≥ 31 in N1mi and N+ patients varied with tumor histology, with only 2% of patients with classic infiltrating lobular cancer having an RS ≥ 31, versus 7-9% of those with ductal carcinoma.

CONCLUSIONS

RS distribution among N0, N1mi, and N+ patients is similar, suggesting a spectrum of biology and potential chemotherapy benefit exists among node-negative and node-positive ER+/HER2- breast cancer patients. If RxPONDER does not show a chemotherapy benefit in N+ patients with a low RS result, our findings indicate that substantial numbers of patients could be spared the burden of chemotherapy.

Trends in breast cancer mortality by stage at diagnosis among young women in the United States

BACKGROUND

Assessing trends in breast cancer survival among young women who are largely unaffected by breast cancer screening will provide important information regarding improvements in the effectiveness of cancer care for breast cancer in the last few decades.

METHODS

The cohort for this study consisted of women who were diagnosed with breast cancer between ages 20 and 39 years from the Surveillance, Epidemiology, and End Results program's 9-registry areas from 1975 to 2015. Trends in the breast cancer incidence rate and survival were assessed among young women.

RESULTS

Among women aged 20 to 39 years, breast cancer incidence increased from 24.6 per 100,000 in 1975 to 31.7 per 100,000 in 2015 (annual percent change, 0.5; 95% confidence interval [CI], 0.4-0.6). Among women with breast cancer, 5-year breast-cancer-specific survival increased significantly from 74.0% during 1975 to 1979 to 88.5% during 2010 to 2015 (hazard ratio for dying from breast cancer for 2010-2015 vs 1975-1979, 0.37; 95% CI, 0.32-0.41). The increase in cancer-specific survival reached a plateau in 2005; however, among young women with metastatic breast cancer, it continued to increase after 2005, from 45.6% during 2005 to 2009 to 56.5% during 2010 to 2015 (hazard ratio for dying from breast cancer for 2010-2015 vs 2005-2009, 0.74; 95% CI, 0.60-0.92). Similar patterns also were observed for 5-year overall survival and among women aged 20 to 29 years and those aged 30 to 39 years.

CONCLUSIONS

There were substantial improvements in the effectiveness of breast cancer treatment on overall and cancer-specific survival from 1975 to 2015. However, improvements appeared to have reached a plateau after 2005, except among young women with metastatic breast cancer, in whom survival continued to improve throughout the period.

Multilevel Influences on Patient-Oncologist Communication about Genomic Test Results: Oncologist Perspectives

Thousands of women with early-stage breast cancer receive gene-expression profile (GEP) tests to guide chemotherapy decisions. However, many patients report a poor understanding of how their test results inform treatment decision-making. We applied models of patient-centered communication and informed decision-making to assess which variables oncologists' perceive as most influential to effective communication with their patients about GEP results and intervention modalities and approaches that could support more effective conversations about treatment decisions in routine clinical care. Medical oncologists who were part of a practice group in the mid-Atlantic US completed an online, cross-sectional survey in 2016. These data were merged with de-identified electronic patient and practice data. Of the 83 oncologists contacted, 29 completed the survey (35% response rate, representing 52% of the test-eligible patients in the practice network). There were no significant differences between survey responders and nonresponders. Oncologists reported patient-related variables as most influential, including performance status (65.5%), pretesting preferences for chemotherapy (55.2%), and comprehension of complex test results (55.2%). Oncologists endorsed their experience with testing (58.6%) and their own confidence in using the test results (48.3%) as influential as well. They indicated that a clinical decision support tool incorporating patient comorbidities, age, and potential benefits from chemotherapy would support their own practice and that they could share these results and other means of communication support using print materials (79.3%) with their patients in clinic (72.4%). These preferred intervention characteristics could be integrated into routine care, ultimately facilitating more effective communication about genomic testing (such as GEP) and its role in treatment selection.

Breast Cancers of Special Histologic Subtypes Are Biologically Diverse

BACKGROUND/OBJECTIVE

Cancers classified as "special histologic subtypes" are felt to have a good prognosis. We used the 21-gene Oncotype DX Breast Recurrence Score^® multigene assay to examine prognostic variation within special histologic subtypes. We also examined the Recurrence Score^® (RS) distribution among the more common ductal (IDC) and lobular (ILC) cancers.

METHODS

610,350 tumor specimens examined in the Genomic Health clinical laboratory from 2/2004 to 8/2017 were included. Specimen histology was classified centrally using a single H&E slide and World Health Organization criteria. RS distribution (low < 18, intermediate 18-30, and high ≥ 31) was compared among histologic subtypes.

RESULTS

Median patient age was 60 years (IQR 51-67); 80% were node negative. Most patients had low RS results (59.2%); only 9.5% had high results. The lowest mean RS was seen in the papillary subtype (11); the highest in the IDC group (18.4). Mean RS for all special subtypes was lower than that of IDC patients. When the high RS threshold was decreased from 31 to 25, as used in the TAILORx and RxPONDER trials, the number of high RS-result patients increased from 9.5% to 16.8%. Patients with ILC had a lower mean RS result than patients with IDC, 16.5 versus 18.4.

CONCLUSION

There is substantial diversity in predicted prognosis among patients with cancers classified as special histologic subtypes, with 12-25% having intermediate RS results and 0.5-9% having high RS results. Pending further definition of the role of chemotherapy for patients with intermediate RS results by TAILORx and RxPONDER, the RS result may help to inform systemic therapy decisions in these patients.

EarlyR: A Robust Gene Expression Signature for Predicting Outcomes of Estrogen Receptor-Positive Breast Cancer

INTRODUCTION

Early stage estrogen receptor (ER)-positive breast cancer may be treated with chemotherapy in addition to hormone therapy. Currently available molecular signatures assess the risk of recurrence and the benefit of chemotherapy; however, these tests may have large intermediate risk groups, limiting their usefulness.

METHODS

The EarlyR prognostic score was developed using integrative analysis of microarray data sets and formalin-fixed, paraffin-embedded-based quantitative real-time PCR assay and validated in Affymetrix data sets and METABRIC cohort using Cox proportional hazards models and Kaplan-Meier survival analysis. Concordance index was used to measure the probability of prognostic score agreement with outcome.

RESULTS

The EarlyR score and categorical risk strata (EarlyR-Low, EarlyR-Int, EarlyR-High) derived from expression of ESPL1, MKI67, SPAG5, PLK1 and PGR was prognostic of 8-year distant recurrence-free interval in Affymetrix (categorical P = 3.5 × 10^-14; continuous P = 8.8 × 10^-15) and METABRIC (categorical P < 2.2 × 10^-16; continuous P < 10^-16) data sets of ER⁺ breast cancer. Similar results were observed for the breast cancer-free interval end point. At most 13% of patients were intermediate risk and at least 66% patients were low risk in both ER⁺ cohorts. The EarlyR score was significantly prognostic (distant recurrence-free interval; P < .001) in both lymph node-negative and lymph node-positive patients and was independent from clinical factors. EarlyR and surrogates of current molecular signatures were comparable in prognostic significance by concordance index.

CONCLUSION

The 5-gene EarlyR score is a robust prognostic assay that identified significantly fewer patients as intermediate risk and more as low risk than currently available assays. Further validation of the assay in clinical trial-derived cohorts is ongoing.

Breast cancer-specific survival by age: Worse outcomes for the oldest patients

BACKGROUND

Although breast cancer often is perceived to be indolent in older women, breast cancer outcomes in the oldest patients are variable. In the current study, the authors examined breast cancer-specific death by age, stage, and disease subtype in a large, population-based cohort.

METHODS

Using Surveillance, Epidemiology, and End Results data, a total of 486,118 women diagnosed with American Joint Committee on Cancer stage I to IV breast cancer between 2000 and 2012 were identified. Using a series of Fine and Gray regression models to account for competing risk, the authors examined the risk of breast cancer-specific death by age and stage (I-IV) for subcohorts with hormone receptor (HR)-positive, HR-negative, human epidermal growth factor receptor 2-positive, and triple-negative disease, adjusting for demographic and clinical variables.

RESULTS

Overall, 18% of women were aged 65 to 74 years, 13% were aged 75 to 84 years, and 4% were aged ≥85 years. Regardless of stage of disease within the HR-positive and HR-negative cohorts, patients aged ≥75 years (vs those aged 55-64 years) experienced a higher adjusted hazard of breast cancer-specific death, which was particularly evident for those with early-stage, HR-positive disease (hazard ratio for those aged 75-84 years, 1.88 [95% confidence interval, 1.68-2.09] and hazard ratio for those aged ≥85 years, 3.59 [95% confidence interval, 3.12-4.13] [both for stage I disease]). In the cohorts with human epidermal growth factor receptor 2-positive and triple-negative disease, women aged ≥70 years had a consistently higher risk of breast cancer-specific death across disease stages (vs those aged 51-60 years), with the exception of stage IV triple-negative disease.

CONCLUSIONS

Older patients experience worse breast cancer outcomes, regardless of disease subtype and stage. With an increasing number of older patients anticipated to develop breast cancer in the future, addressing disparities for older patients must emerge as a clinical and research priority. Cancer 2018;124:2184-91. © 2018 American Cancer Society.

Uptake of BRCA 1/2 and oncotype DX testing by medical and surgical oncologists

PURPOSE

The diffusion of genomic testing is critical to the success of precision medicine, but there is limited information on oncologists' uptake of genetic technology. We aimed to assess the frequency with which medical oncologists and surgeons order BRCA 1/2 and Oncotype DX testing for breast cancer patients.

METHODS

We surveyed 732 oncologists and surgeons treating breast cancer patients. Physicians were from Florida, New York, New Jersey, and Pennsylvania, and were listed in the 2010 AMA Masterfile or identified by patients.

RESULTS

80.6% of providers ordered BRCA 1/2 testing at least sometimes and 85.4% ordered Oncotype DX (p = 0.01). More frequent ordering of BRCA 1/2 was associated with more positive attitudes toward genetic innovation (OR 1.14, p = 0.001), a belief that testing was likely to be covered by patients' insurance (OR 2.84, p < 0.001), and more frequent ordering of Oncotype DX testing (OR 8.69, p < 0.001). More frequent use of Oncotype DX was associated with a belief that testing was likely to be covered by insurance (OR 7.33, p < 0.001), as well as with more frequent ordering of BRCA 1/2 testing (OR 9.48, p < 0.001).

CONCLUSIONS

Nearly one in five providers never or rarely ever ordered BRCA 1/2 testing for their breast cancer patients, and nearly 15% never or rarely ever ordered Oncotype DX. Less frequent ordering of BRCA 1/2 is associated with less frequent use of Oncotype DX testing, and vice versa. Those who do not order BRCA 1/2 testing report less positive attitudes toward genetic innovation. Further education of this subset of providers regarding the benefits of precision medicine may enable more rapid diffusion of genetic technology.

Recent Trends in Chemotherapy Use and Oncologists' Treatment Recommendations for Early-Stage Breast Cancer

Background

There is growing concern about overtreatment of breast cancer as outcomes have improved over time. However, little is known about how chemotherapy use and oncologists' recommendations have changed in recent years.

Methods

We surveyed 5080 women (70% response rate) diagnosed with breast cancer between 2013 and 2015 and accrued through two Surveillance, Epidemiology, and End Results registries (Georgia and Los Angeles) about chemotherapy receipt and their oncologists' chemotherapy recommendations. We surveyed 504 attending oncologists (60.3% response rate ) about chemotherapy recommendations in node-negative and node-positive case scenarios. We conducted descriptive statistics of chemotherapy use and patients' report of oncologists' recommendations and used a generalized linear mixed model of chemotherapy use according to time and clinical factors. All statistical tests were two-sided.

Results

The analytic sample was 2926 patients with stage I-II, estrogen receptor-positive, human epidermal growth factor receptor 2-negative breast cancer. From 2013 to 2015, keeping other factors constant, chemotherapy use was estimated to decline from 34.5% (95% confidence interval [CI] = 30.8% to 38.3%) to 21.3% (95% CI = 19.0% to 23.7%, P < .001). Estimated decline in chemotherapy use was from 26.6% (95% CI = 23.0% to 30.7%) to 14.1% (95% CI = 12.0% to 16.3%) for node-negative/micrometastasis patients and from 81.1% (95% CI = 76.6% to 85.0%) to 64.2% (95% CI = 58.6% to 69.6%) for node-positive patients. Use of the 21-gene recurrence score (RS) did not change among node-negative/micrometastasis patients, and increasing RS use in node-positive patients accounted for one-third of the chemotherapy decline. Patients' report of oncologists' recommendations for chemotherapy declined from 44.9% (95% CI = 40.2% to 49.7%) to 31.6% (95% CI = 25.9% to 37.9%), controlling for other factors. Oncologists were much more likely to order RS if patient preferences were discordant with their recommendations (67.4%, 95% CI = 61.7% to 73.0%, vs 17.5%, 95% CI = 13.1% to 22.0%, concordant), and they adjusted recommendations based on patient preferences and RS results.

Conclusions

For both node-negative/micrometastasis and node-positive patients, chemotherapy receipt and oncologists' recommendations for chemotherapy declined markedly over time, without substantial change in practice guidelines. Results of ongoing trials will be essential to confirm the quality of this approach to breast cancer care.

Cost-Effectiveness Analyses of the 21-Gene Assay in Breast Cancer: Systematic Review and Critical Appraisal

Purpose Prior studies examining cost effectiveness of the 21-gene assay (Oncotype DX [ODX]) for women with hormone receptor-positive, early-stage breast cancer have yielded disparate results. We aimed to explore why these analyses may have yielded different conclusions. Methods We conducted a systematic literature review of cost-effectiveness analyses (CEAs) of ODX. We examined the extent to which the structure of CEA modeling, the assumptions of the models, and the selection of input parameters influenced cost-effectiveness estimates. We also explored the prevalence of industry funding and whether industry funding was associated with study designs favoring ODX. Results We identified 27 analyses, 15 of which received industry funding. In 18 studies, the clinical characteristics (eg, tumor size and grade) commonly used to make chemotherapy decisions were not incorporated into simulation modeling; thus, these studies would favor ODX being cost effective and might not reflect clinical practice. Most studies ignored the heterogeneous effect of ODX on chemotherapy use; only five studies assumed that ODX would increase chemotherapy use for clinically low-risk patients but decrease chemotherapy use for clinically high-risk patients. No study used population-based joint distributions of ODX recurrence score and tumor characteristics, and 12 studies inappropriately assumed that chemotherapy would increase distant recurrence for the low recurrence score group; both approaches overestimated the benefits of ODX. Industry-funded studies tended to favor ODX; all five studies that reported ODX as being cost saving were industry funded. In contrast, two studies that reported an incremental cost-effectiveness ratio > $50,000 per quality-adjusted life-year were not funded by industry. Conclusion Although a majority of published analyses indicated that ODX is cost effective, they incorporated study designs that can increase the risk of bias.

Immunohistochemical Ki67 after short-term hormone therapy identifies low-risk breast cancers as reliably as genomic markers

Background

The purpose of this study was to test whether immunohistochemical (IHC) Ki67 levels after short-term preoperative hormone therapy (post-Ki67) predict similar numbers of patients with favorable prognoses as genomic markers.

Results

Thirty paired cases (60 samples) were enrolled in this study. Post-Ki67 levels were significantly lower than pre-treatment Ki67 levels (P < 0.001). Post-Ki67 predicted more low-risk cases (83.3%, 25/30) than pre-genomic surrogate signature(GSS) (66.7%: 20/30), but the difference in predictive power was not significant (P = 0.233). Proliferation (MKI67, STK15, Survivin, CCNB1, and MYBL2) and estrogen (ER, PGR, BCL2, and SCUBE2) related signatures were significantly downregulated after therapy (P < 0.001 and 0.041, respectively).

Materials and Methods

Core needle biopsy specimens of primary breast cancer were collected at Okayama University Hospital from hormone receptor-positive and human epidermal growth factor 2-negative patients that subsequently received two weeks of neoadjuvant hormone therapy. Paired post-treatment specimens from surgical samples were also collected. IHC Ki67 levels and GSS were compared between pre- and post-hormone treatment samples. Changes of gene expression pattern in short-term hormone therapy were also assessed.

Conclusions

IHC based post-Ki67 levels may have distinct predictive power compared with the naïve IHC Ki67. Future studies with larger cohorts and longer follow-up periods may be needed to validate our results.

Racial Differences in 21-Gene Recurrence Scores Among Patients With Hormone Receptor-Positive, Node-Negative Breast Cancer

Purpose The 21-gene recurrence score (RS) breast cancer assay is clinically used to quantify risk of 10-year distant recurrence by category (low, < 18; intermediate, 18 to 30; high, ≥ 31) for treatment management among women diagnosed with hormone receptor-positive, human epidermal growth factor receptor 2-negative, lymph node-negative breast cancer. Although non-Hispanic black (NHB) women have worse prognosis compared with non-Hispanic white (NHW) women, the equivalency of 21-gene RS across racial groups remains unknown. Patients and Methods Using the Metropolitan Detroit Cancer Surveillance System, we identified women who were diagnosed with hormone receptor-positive, human epidermal growth factor receptor 2-negative, lymph node-negative invasive breast cancer between 2010 and 2014. Multinomial logistic regression was used to quantify racial differences in 21-gene RS category. Results We identified 2,216 women (1,824 NHW and 392 NHB) with invasive breast cancer who met clinical guidelines for and underwent 21-gene RS testing. The mean RS was significantly higher in NHBs compared with NHWs (19.3 v 17.0, respectively; P = .0003), where NHBs were more likely to present with high-risk tumors compared with NHWs (14.8% v 8.3%, respectively; P = .0004). These differences were limited to patients younger than 65 years at diagnosis, among whom NHBs had significantly higher RS compared with NHWs (20 to 49 years: 23.6 v 17.3, respectively; P < .001 and 50 to 64 years: 19.6 v 17.4, respectively; P = .023). NHBs remained more likely to have high-risk tumors compared with NHWs after adjusting for age, clinical stage, tumor grade, and histology (odds ratio [OR], 1.75; 95% CI, 1.18 to 2.59). Conclusion NHBs who met clinical criteria for 21-gene RS testing had tumors with higher estimated risks of distant recurrence compared with NHWs. Further study is needed to elucidate whether differences in recurrence are observed for these women, which would have clinical implications for 21-gene RS calibration and treatment recommendations in NHB patients.

Spotlight on the utility of the Oncotype DX® breast cancer assay

The Oncotype DX^® assay was developed to address the need for optimizing the selection of adjuvant systemic therapy for patients with estrogen receptor (ER)-positive, lymph node-negative breast cancer. It has ushered in the era of genomic-based personalized cancer care for ER-positive primary breast cancer and is now widely utilized in various parts of the world. Together with several other genomic assays, Oncotype DX has been incorporated into clinical practice guidelines on biomarker use to guide treatment decisions. The Oncotype DX result is presented as the recurrence score which is a continuous score that predicts the risk of distant disease recurrence. The assay, which provides information on clinicopathological factors, has been validated for use in the prognostication and prediction of degree of adjuvant chemotherapy benefit in both lymph node-positive and lymph node-negative early breast cancers. Clinical studies have consistently shown that the Oncotype DX has a significant impact on decision making in adjuvant therapy recommendations and appears to be cost-effective in diverse health care settings. In this article, we provide an overview of the validation and clinical impact studies for the Oncotype DX assay. We also discuss its potential use in the neoadjuvant setting, as well as the more recent prospective validation trials, and the economic and utility implications of studies that use a lower cutoff score to define low-risk disease.

Influence of provider factors and race on uptake of breast cancer gene expression profiling

BACKGROUND

Gene expression profiling (GEP) has been rapidly adopted for early breast cancer and can aid in chemotherapy decision making. Study results regarding racial disparities in testing are conflicting, and may reflect different care settings. To the authors' knowledge, data regarding the influence of provider factors on testing are scarce.

METHODS

The authors used a statewide, multipayer, insurance claims database linked to cancer registry records to examine the impact of race and provider characteristics on GEP uptake in a cohort of patients newly diagnosed with breast cancer between 2005 and 2012. Incidence proportion models were used to examine the adjusted likelihood of testing. Models were stratified by lymph node status (N0 vs N1).

RESULTS

Among 11,958 eligible patients, 23% of black and 26% of non-Hispanic white patients received GEP. Among patients with N0 disease, black individuals were 16% less likely to receive testing after adjustment for clinical factors and the provider's specialty and volume of patients with breast cancer (95% confidence interval, 0.77-0.93). Adjustment for provider characteristics did not attenuate the effect of race on testing. Patients of middle-volume providers were more likely to be tested compared with those with either high-volume or low-volume providers, whereas patients seeing a medical oncologist were more likely to be tested compared with those whose only providers were from surgical specialties.

CONCLUSIONS

Provider volume and specialty were found to be significant predictors of GEP use, but did not explain racial disparities in testing. Further research concerning the key contributors to lagging test use among black women is needed to optimize the equitable use of GEPs and support personalized treatment decision making for all patients. Cancer 2018;124:1743-51. © 2018 American Cancer Society.

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.

21-gene recurrence assay in patients receiving intraoperative radiotherapy: are "favorable" characteristics a surrogate for low recurrence?

Background

Intraoperative radiotherapy (IORT) has gained momentum for early stage and favorable breast cancers (BC). The 21-gene recurrence assay guides treatment of hormone positive and node-negative BC.

Methods

Analysis of 82 invasive BC treated with breast conservation surgery (BCS) and IORT 2013-2015. Data collection included patient demographics, tumor characteristics, nodal status, recurrence test (RS) and adjuvant therapy.

Results

The mean age was 68 years. Tumors were stage Ia (86.6%), 3.6% Ib and 9.8% IIa. Of 50 patients (61.0%) with RS testing, 72% (n=36) were low risk (RS 0-17), with 28% (n=14) at intermediate risk (RS 18-30). The 39% (n=32) of patients without RS testing, were more likely to have smaller tumors (1.3 vs. 0.9 cm) and age >70 (P<0.05).

Conclusions

Most patients selected for IORT based on clinical features were indeed low risk based on RS. Given the limited long-term clinical outcome and safety data of this technique, additional investigation is needed.

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.

Impacts of Early Guideline-Directed 21-Gene Recurrence Score Testing on Adjuvant Therapy Decision Making

PURPOSE

The 21-gene recurrence score (RS) assay is used to help formulate adjuvant chemotherapy recommendations for patients with estrogen receptor-positive, early-stage breast cancer. Most frequently, medical oncologists order RS after surgery. Results take an additional 2 weeks to return, which can delay decision making. We conducted a prospective quality-improvement project to assess the impact of early guideline-directed RS ordering by surgeons before the first visit with a medical oncologist on adjuvant therapy decision making.

MATERIALS AND METHODS

Surgical oncologists ordered RS testing following National Comprehensive Cancer Network guidelines at time of diagnosis or at time of surgery between July 1, 2015 and December 31, 2015. We measured the testing rate of patients eligible for RS, time to chemotherapy decisions, rates of chemotherapy use, accrual to RS-based clinical trials, cost, and physician acceptance of the policy and compared the results to patients who met eligibility criteria for early guideline-directed testing during the 6 months before the project.

RESULTS

Ninety patients met eligibility criteria during the testing period. RS was ordered for 91% of patients in the early testing group compared with 76% of historical controls ( P < .001). Median time to chemotherapy decision was significantly shorter in the early testing group (20 days; 95% CI, 17 to 23 days) compared with historical controls (32 days; 95% CI, 29 to 35 days; P < .001). There were no significant differences in time to chemotherapy initiation, chemotherapy use, RS-based trial enrollment, or calculated costs between the groups.

CONCLUSION

Early guideline-directed RS testing in selected patients is an effective way to shorten time to treatment decisions.

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.

Towards decision-making using individualized risk estimates for personalized medicine: A systematic review of genomic classifiers of solid tumors

Recent advances in the understanding of the genetic underpinnings of cancer offer the promise to customize cancer treatments to the individual through the use of genomic classifiers (GCs). At present, routine clinical utilization of GCs is uncommon and their current scope and status, in a broad sense, are unknown. As part of a registered review (PROSPERO 2014:CRD42014013371), we systematically reviewed the literature evaluating the utility of commercially available GCs by searching Ovid Medline (PubMed), EMBASE, the Cochrane Database of Systematic Reviews, and CINAHL on September 2, 2014. We excluded articles involving pediatric malignancies, non-solid or non-invasive cancers, hereditary risk of cancer, non-validated GCs, and GCs involving fewer than 3 biomarkers. A total of 3,625 studies were screened, but only 37 met the pre-specified inclusion criteria. Of these, 15 studies evaluated outcomes and clinical utility of GCs through clinical trials, and the remainder through the use of mathematical models. Most studies (29 of 37) were specific to hormone-receptor positive breast cancer, whereas only 4 studies evaluated GCs in non-breast cancer (prostate, colon, and lung cancers). GCs have spurred excitement across disciplines in recent decades. While there are several GCs that have been validated, the general quality of the data are weak. Further research, including prospective validation is needed, particularly in the non-breast cancer GCs.

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.

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.

Endocrine therapy initiation, discontinuation and adherence and breast imaging among 21-gene recurrence score assay-eligible women under age 65

BACKGROUND

Aside from chemotherapy utilization, limited data are available on the relationship between gene expression profiling (GEP) testing and breast cancer care. We assessed the relationship between GEP testing and additional variables and the outcomes of endocrine therapy initiation, discontinuation and adherence, and breast imaging exams in women under age 65 years.

METHODS

Data from five state cancer registries were linked with claims data and GEP results. We assessed variables associated with survivorship care outcomes in an incident cohort of 5014 commercially insured women under age 65 years, newly diagnosed with stage I or II hormone-receptor-positive, human epidermal growth factor receptor 2 (HER2) non-positive breast cancer from 2006 to 2010.

RESULTS

Among tested women, those with high Oncotype DX® Breast Recurrence Score® (RS) were significantly less likely to initiate endocrine therapy than women with low RS tumors (OR 0.40 (95% CI 0.20 to 0.81); P = 0.01). Among all test-eligible women, receipt of Oncotype DX testing was associated with a greater likelihood of endocrine therapy initiation (OR 2.48 (95% CI 2.03 to 3.04); P <0.0001). The odds of initiation were also significantly higher for tested vs. untested women among women who did not initiate chemotherapy within six months of diagnosis (OR 3.25 (95% CI 2.53 to 4.16)), with no effect in women who received chemotherapy. Discontinuation and adherence and breast imaging exams were unrelated to tested status or RS.

CONCLUSIONS

Lower endocrine therapy initiation rates among women with high RS tumors and among untested women not receiving chemotherapy are concerning, given its established efficacy. Additional research is needed to suggest mechanisms to close this gap.

Second Opinions From Medical Oncologists for Early-Stage Breast Cancer: Prevalence, Correlates, and Consequences

IMPORTANCE

Advances in the evaluation and treatment of breast cancer have made the clinical decision-making context much more complex. A second opinion from a medical oncologist may facilitate decision making for women with breast cancer, yet little is known about second opinion use.

OBJECTIVE

To investigate the patterns and correlates of second opinion use and the effect on chemotherapy decisions.

DESIGN, SETTING, AND PARTICIPANTS

A total of 1901 women newly diagnosed with stages 0 to II breast cancer between July 2013 and September 2014 (response rate, 71.0%) were accrued through 2 population-based Surveillance, Epidemiology, and End Results registries (Georgia and Los Angeles County, California) and surveyed about their experiences with medical oncologists, decision making, and chemotherapy use.

MAIN OUTCOMES AND MEASURES

Factors associated with second opinion use were evaluated using logistic regression. Also assessed was the association between second opinion and chemotherapy use, adjusting for chemotherapy indication and propensity for receiving a second opinion. Multiple imputation and weighting were used to account for missing data.

RESULTS

A total of 1901 patients with stage I to II breast cancer (mean [SD] age, 61.6 [11.0] years; 1071 [56.3%] non-Hispanic white) saw any medical oncologist. Analysis of multiply imputed, weighted data (mean n = 1866) showed that 168 (9.8%) (SE, 0.74%) received a second opinion and 54 (3.2%) (SE, 0.47%) received chemotherapy from the second oncologist. Satisfaction with chemotherapy decisions was high and did not differ between those who did (mean [SD], 4.3 [0.08] on a 1- to 5-point scale) or did not (4.4 [0.03]) obtain a second opinion (P = .29). Predictors of second opinion use included college education vs less education (odds ratio [OR], 1.85; 95% CI, 1.24-2.75), frequent use of internet-based support groups (OR, 2.15; 95% CI, 1.12-4.11), an intermediate result on the 21-gene recurrence score assay (OR, 1.85; 95% CI, 1.11-3.09), and a variant of uncertain significance on hereditary cancer genetic testing (OR, 3.24; 95% CI, 1.09-9.59). After controlling for patient and tumor characteristics, second opinion use was not associated with chemotherapy receipt (OR, 1.04; 95% CI, 0.71-1.52).

CONCLUSIONS AND RELEVANCE

Second opinion use was low (<10%) among patients with early-stage breast cancer, and high decision satisfaction regardless of second opinion use suggests little unmet demand. Along with educational level and use of internet support groups, uncertain results on genomic testing predicted second opinion use. Patient demand for second opinions may increase as more complex genomic tests are disseminated.

Oncologist and organizational factors associated with variation in breast cancer multigene testing

PURPOSE

Multigene testing for breast cancer recurrence risk became available in 2007, yet many eligible patients remain untested. This study evaluated variation in testing rates, and oncologist and organizational factors associated with variation, in a setting without financial influences on testing.

METHODS

We conducted a retrospective cohort study using electronic data and oncologist surveys within Kaiser Permanente Northern California, a large integrated health care system. Analyses included all 2974 test eligible patients from 2013 to 2015, 113 oncologists, and 15 practice groups. Receipt of multigene testing was evaluated with generalized linear mixed models.

RESULTS

Overall, 39% of eligible patients had multigene testing, but rates varied widely among practice groups, ranging from 24 to 48% after case mix adjustment. This 24% difference among practices was greater than the variation associated with most patient characteristics, including comorbidities and race/ethnicity, and similar to that associated with tumor size. Practice group and oncologist factors were statistically significant contributors to the variation in testing after adjusting for patient factors. Patients were more likely to be tested if they had a female oncologist (aOR 1.60, 95% CI 1.21-2.12) or were in a practice whose chief had a high testing rate (aOR 1.20, 95% CI 1.12-1.29 per 10% increase in the percent tested).

CONCLUSIONS

Oncologist and leadership practices play a key role in the variation in genomic test use for cancer recurrence risk even in a healthcare system without financial barriers to testing and could be a leverage point for implementing desired practice changes for new genomic advances.