Adjuvant Chemotherapy Guided by a 21-Gene Expression Assay in Breast Cancer

21-gene recurrence score and adjuvant chemotherapy decisions in patients with invasive lobular breast cancer

Aim: To determine the effect of the 21-gene recurrence score (RS) on outcome and chemotherapy decision in breast invasive lobular carcinoma (ILC). Materials & methods: We included 6467 patients with early stage and estrogen receptor–positive ILC from the Surveillance, epidemiology, and end results database. Results: A total of 9.1, 31.4, and 70.1% of patients with low-, intermediate-, and high-risk RS groups received chemotherapy, respectively. A higher RS was independently associated with poor breast cancer-specific survival, and receipt of chemotherapy was not related to better breast cancer-specific survival in low-, intermediate-, or high-risk RS groups. Conclusion: The 21-gene RS could impact chemotherapy decision making in early-stage ILC. However, adjuvant chemotherapy does not appear to improve outcome in high-risk RS cohort.

EarlyR signature predicts response to neoadjuvant chemotherapy in breast cancer

BACKGROUND

EarlyR gene signature uses ESPL1, SPAG5, MKI67, PLK1 and PGR to classify ER+ breast cancer (ER+ BC) into EarlyR-Low, EarlyR-Int, and EarlyR-High risk strata and is prognostic in patients treated with adjuvant chemotherapy. The ability of EarlyR to predict pathological complete response (pCR) and long-term survival following neoadjuvant chemotherapy (NACT) is evaluated herein.

MATERIALS

The ability of EarlyR gene signature to predict pCR was assessed in publicly available Affymetrix microarray datasets (Cohort A; n = 659; 74 pCR events) derived from NACT-treated ER+ BC patients. Distant relapse-free survival (DRFS) results were analyzed in patients treated with NACT and adjuvant hormone therapy (AHT) (n = 281) and compared with patients treated with AHT alone (n = 455) (Cohort B; n = 736; 142 events).

RESULTS

In cohort A, EarlyR was a significant predictor of pCR (p = 5.8 × 10-11) (EarlyR-Low, n = 400, pCR = 40, 5%; EarlyR-Int, n = 69, pCR = 7, 15% and EarlyR-High, n = 190, pCR = 47, 24%). In EarlyR-Low of Cohort B, the 5-year DRFS was not significantly (p = 0.55) different between NACT + AHT [0.81 (95%CI 0.73-0.90)] and AHT-only [0.85 (95%CI 0.81-0.90)]. In contrast, in EarlyR-High, the 5-year DRFS was higher (p = 0.019) in NACT + AHT [0.81 (95%CI 0.70-0.93)] as compared to AHT-only [0.60 (95%CI 0.51-0.71)].

CONCLUSIONS

High EarlyR is strongly associated with pCR in patients treated with neoadjuvant chemotherapy. EarlyR also predicts poor DRFS outcomes for patients in EarlyR-High not receiving NACT, and improved survival in NACT-treated EarlyR-High patients. EarlyR is not only a prognostic assay but also a predictive assay that identifies patients, who are also likely to respond to chemotherapy.

Insights into Molecular Classifications of Triple-Negative Breast Cancer: Improving Patient Selection for Treatment

Triple-negative breast cancer (TNBC) remains the most challenging breast cancer subtype to treat. To date, therapies directed to specific molecular targets have rarely achieved clinically meaningful improvements in outcomes of patients with TNBC, and chemotherapy remains the standard of care. Here, we seek to review the most recent efforts to classify TNBC based on the comprehensive profiling of tumors for cellular composition and molecular features. Technologic advances allow for tumor characterization at ever-increasing depth, generating data that, if integrated with clinical-pathologic features, may help improve risk stratification of patients, guide treatment decisions and surveillance, and help identify new targets for drug development. SIGNIFICANCE: TNBC is characterized by higher rates of relapse, greater metastatic potential, and shorter overall survival compared with other major breast cancer subtypes. The identification of biomarkers that can help guide treatment decisions in TNBC remains a clinically unmet need. Understanding the mechanisms that drive resistance is key to the design of novel therapeutic strategies to help prevent the development of metastatic disease and, ultimately, to improve survival in this patient population.

Clinical validation of Ki67 by quantitative reverse transcription-polymerase chain reaction (RT-PCR) in HR+/HER2- early breast cancer

Objective: To evaluate the clinical value of Ki67 by RT-PCR, we investigated the concordance of Ki67 expression by IHC and by RT-PCR, and assessed their prognostic value in HR+/HER2- early breast cancer.

Methods: 1259 HR+/HER2- early breast cancer patients treated at Ruijin Hospital with recurrence score were retrospectively recruited. RT-PCR assay measurement of Ki67 was conducted by 21-gene expression assay and compared with IHC measurement of Ki67 using chi-square tests. X-tile program was used to determine the optimal cutoff point for Ki67 by RT-PCR. Survival analyses were performed by Kaplan-Meier analysis and log-rank tests, and hazard ratios were derived from the Cox proportional hazards model.

Results: Ki67 by RT-PCR had a weak positive correlation with Ki67 by IHC. Pathology, grade and Ki67 expression by IHC were significantly related to the concordance between two assays, and most discordance cases were seen in patients with Ki67 ranging from 10 to 29. The estimated 3-year DFS was 96.0% in low, and 92.5% in high expression group of Ki67 by IHC, 97.0% in low and 90.4% in high expression group of Ki67 by RT-PCR. Univariate and multivariate analysis in the whole population indicated that only Ki67 by RT-PCR—but not intrinsic subtype or recurrence score—was an independent factor for DFS.

Conclusions: Ki67 assessed by RT-PCR assay was weakly correlated to Ki67 by IHC. Using 5.68 as cutoff point, Ki67 by RT-PCR had shown potential as a prognostic biomarker in HR+/HER2- early breast cancer.

Whole genome sequencing of breast cancer

Breast cancer was the first to take advantage of targeted therapy using endocrine therapy, and for up to 20% of all breast cancer patients a further significant improvement has been obtained by HER2‐targeted therapy. Greater insight in precision medicine is to some extent driven by technical and computational progress, with the first wave of a true technical advancement being the application of transcriptomic analysis. Molecular subtyping further improved our understanding of breast cancer biology and has through a new tumor classification enabled allocation of personalized treatment regimens. The next wave in technical progression must be next‐generation‐sequencing which is currently providing new and exciting results. Large‐scale sequencing data unravel novel somatic and potential targetable mutations as well as allowing the identification of new candidate genes predisposing for familial breast cancer. So far, around 15% of all breast cancer patients are genetically predisposed with most genes being factors in pathways implicated in genome maintenance. This review focuses on whole‐genome sequencing and the new possibilities that this technique, together with other high‐throughput analytic approaches, provides for a more individualized treatment course of breast cancer patients.

Molecular and epigenetic profiles of BRCA1-like hormone-receptor-positive breast tumors identified with development and application of a copy-number-based classifier

Background

BRCA1-mutated cancers exhibit deficient homologous recombination (HR) DNA repair, resulting in extensive copy number alterations and genome instability. HR deficiency can also arise in tumors without a BRCA1 mutation. Compared with other breast tumors, HR-deficient, BRCA1-like tumors exhibit worse prognosis but selective chemotherapeutic sensitivity. Presently, patients with triple negative breast cancer (TNBC) who do not respond to hormone endocrine-targeting therapy are given cytotoxic chemotherapy. However, more recent evidence showed a similar genomic profile between BRCA1-deficient TNBCs and hormone-receptor-positive tumors. Characterization of the somatic alterations of BRCA1-like hormone-receptor-positive breast tumors as a group, which is currently lacking, can potentially help develop biomarkers for identifying additional patients who might respond to chemotherapy.

Methods

We retrained and validated a copy-number-based support vector machine (SVM) classifier to identify HR-deficient, BRCA1-like breast tumors. We applied this classifier to The Cancer Genome Atlas (TCGA) and Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) breast tumors. We assessed mutational profiles and proliferative capacity by covariate-adjusted linear models and identified differentially methylated regions using DMRcate in BRCA1-like hormone-receptor-positive tumors.

Results

Of the breast tumors in TCGA and METABRIC, 22% (651/2925) were BRCA1-like. Stratifying on hormone-receptor status, 13% (302/2405) receptor-positive and 69% (288/417) triple-negative tumors were BRCA1-like. Among the hormone-receptor-positive subgroup, BRCA1-like tumors showed significantly increased mutational burden and proliferative capacity (both P < 0.05). Genome-scale DNA methylation analysis of BRCA1-like tumors identified 202 differentially methylated gene regions, including hypermethylated BRCA1. Individually significant CpGs were enriched for enhancer regions (P < 0.05). The hypermethylated gene sets were enriched for DNA and chromatin conformation (all Bonferroni P < 0.05).

Conclusions

To provide insights into alternative classification and potential therapeutic targeting strategies of BRCA1-like hormone-receptor-positive tumors we developed and applied a novel copy number classifier to identify BRCA1-like hormone-receptor-positive tumors and their characteristic somatic alteration profiles.

Electronic supplementary material

The online version of this article (10.1186/s13058-018-1090-z) contains supplementary material, which is available to authorized users.

Breast Cancer Treatment: A Review

IMPORTANCE

Breast cancer will be diagnosed in 12% of women in the United States over the course of their lifetimes and more than 250 000 new cases of breast cancer were diagnosed in the United States in 2017. This review focuses on current approaches and evolving strategies for local and systemic therapy of breast cancer.

OBSERVATIONS

Breast cancer is categorized into 3 major subtypes based on the presence or absence of molecular markers for estrogen or progesterone receptors and human epidermal growth factor 2 (ERBB2; formerly HER2): hormone receptor positive/ERBB2 negative (70% of patients), ERBB2 positive (15%-20%), and triple-negative (tumors lacking all 3 standard molecular markers; 15%). More than 90% of breast cancers are not metastatic at the time of diagnosis. For people presenting without metastatic disease, therapeutic goals are tumor eradication and preventing recurrence. Triple-negative breast cancer is more likely to recur than the other 2 subtypes, with 85% 5-year breast cancer-specific survival for stage I triple-negative tumors vs 94% to 99% for hormone receptor positive and ERBB2 positive. Systemic therapy for nonmetastatic breast cancer is determined by subtype: patients with hormone receptor-positive tumors receive endocrine therapy, and a minority receive chemotherapy as well; patients with ERBB2-positive tumors receive ERBB2-targeted antibody or small-molecule inhibitor therapy combined with chemotherapy; and patients with triple-negative tumors receive chemotherapy alone. Local therapy for all patients with nonmetastatic breast cancer consists of surgical resection, with consideration of postoperative radiation if lumpectomy is performed. Increasingly, some systemic therapy is delivered before surgery. Tailoring postoperative treatment based on preoperative treatment response is under investigation. Metastatic breast cancer is treated according to subtype, with goals of prolonging life and palliating symptoms. Median overall survival for metastatic triple-negative breast cancer is approximately 1 year vs approximately 5 years for the other 2 subtypes.

CONCLUSIONS AND RELEVANCE

Breast cancer consists of 3 major tumor subtypes categorized according to estrogen or progesterone receptor expression and ERBB2 gene amplification. The 3 subtypes have distinct risk profiles and treatment strategies. Optimal therapy for each patient depends on tumor subtype, anatomic cancer stage, and patient preferences.

Development of a Precise, Clinically Relevant, Digital Classification Schema for Cancer

PURPOSE

Health care transactions depend on the efficiency of digital codes. The International Classification of Diseases and Related Health Problems (ICD) coding system, which is the most commonly used digital system, fails to capture the complexity of oncologic diseases. Because important prognostic information such as cancer stage and genomic markers are missing, the potential for ICD codes to define and compare patient cohorts is severely limited. A more precise, clinically relevant, digital classification schema that incorporates prognostic elements would address these needs.

METHODS

Working with cancer disease-specific experts, a new digital classification scheme, known as the Cota Nodal Address (CNA) system, was developed. The CNA has six components that define the disease of interest and incorporate all standard-of-care prognostic and predictive markers related to the particular cancer, including patient features.

RESULTS

Properly sorted into homogeneous groupings of patients with similar prognostic characteristics, the CNA system facilitated big data analytic approaches, such as evaluations of population health, identification of variation in treatment decisions, and the enablement of value-based payment models. The schema has been applied to patients with breast cancer at a large tertiary cancer care hospital and a regional community cancer care network and has facilitated the creation and application of value-based payment models.

CONCLUSION

The development and potential uses of a prognosis-based classification system are reviewed herein. Compared with ICD coding, the greater precision of the schema permits improved analyses of variance in treatment, outcomes, and costs in cancer care management.

Use and Impact of the 21-Gene Recurrence Score in Relation to the Clinical Risk of Developing Metastases in Early Breast Cancer Patients in the Netherlands

BACKGROUND

The nationwide use of the 21-gene recurrence score (21-RS) and implications regarding chemotherapy administration in relation to clinical risk in early breast cancer patients are investigated.

METHODS

Breast cancer patients surgically treated between 2014 and 2016 were selected from the Netherlands Cancer Registry and categorized as having a clinical low, intermediate, or high risk of developing metastases. Deployment of the 21-RS is advocated in patients with an intermediate risk of developing metastases. The use and impact of the 21-RS test result on chemotherapy administration were assessed in relation to the clinical risk as well as patient and tumor characteristics; χ2 tests were used for analysis.

RESULTS

Of all patients, 20,488 were considered as clinical low-, 4,309 as intermediate-, and 15,266 as high-risk patients. The 21-RS was deployed in 0.1% (n = 23), 3.2% (n = 137), and 0.6% (n = 90) of these categories, respectively. In the clinical intermediate-risk group, the 21-RS assigned 73.7, 13.1, and 13.1% of patients to the genomic low-, intermediate-, and high-risk category, respectively. Adherence to the 21-RS was 95.6% in these patients.

CONCLUSION

In the Netherlands, the 21-RS test is applied both inside and outside the guideline-directed area. In case of discordance between the genomic and clinical risk, patients were treated in line with the result of the 21-RS.

Recent advances in breast cancer research impacting clinical diagnostic practice

During the last decade, the genomics revolution has driven critical advances in molecular oncology and pathology, and a deeper appreciation of heterogeneity that is beginning to reshape our thinking around diagnostic classification. Recent developments have seen existing classification systems modified and improved where possible, gene-based diagnostics implemented and tumour-immune interactions modulated. We present a detailed discussion of this progress, including advances in the understanding of breast tumour classification, e.g. mixed ductal-lobular tumours and the spectrum of triple-negative breast cancer. The latest information on clinical trials and the implementation of gene-based diagnostics, including MammaPrint and Oncotype Dx and others, is synthesised, and emerging targeted therapies, as well as the burgeoning immuno-oncology field, and their relevance in breast cancer, are discussed. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Genomic Risk Predicts Molecular Imaging-detected Metastatic Nodal Disease in Prostate Cancer

BACKGROUND

The Decipher genomic classifier (GC) is increasingly being used to determine metastasis risk in men with localized prostate cancer (PCa). Whether GCs predict for the presence of occult metastatic disease at presentation or subsequent metastatic progression is unknown.

OBJECTIVE

To determine if GC scores predict extraprostatic ⁶⁸Ga prostate-specific membrane antigen (⁶⁸Ga-PSMA-11) positron emission tomography (PET) positivity at presentation.

DESIGN, SETTING, AND PARTICIPANTS

Between December 2015 and September 2018, 91 PCa patients with both GC scores and pretreatment ⁶⁸Ga-PSMA-11 PET scans were identified. Risk stratification was performed using the National Comprehensive Cancer Network (NCCN), Cancer of the Prostate Risk Assessment (CAPRA), and GC scores.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Logistic regression was used to identify factors correlated with PSMA-positive disease.

RESULTS AND LIMITATIONS

The NCCN criteria identified 23 (25.3%) and 68 patients (74.7%) as intermediate and high risk, while CAPRA scores revealed 28 (30.8%) and 63 (69.2%) as low/intermediate and high risk, respectively. By contrast, only 45 patients (49.4%) had high-risk GC scores. PSMA-avid pelvic nodal involvement was identified in 27 patients (29.7%). Higher GC score was significantly associated with pelvic nodal involvement (odds ratio [OR] 1.38 per 0.1 units; p=0.009) and any PSMA-avid nodal involvement (pelvic or distant; OR 1.40 per 0.1 units; p=0.007). However, higher GC score was not significantly associated with PSMA-avid osseous metastases (OR 1.11 per 0.1 units; p=0.50). Limitations include selection bias for patients able to receive both tests and the sample size.

CONCLUSIONS

Each 0.1-unit increase in GC score was associated with an approximate 40% increase in the odds of PSMA-avid lymph node involvement. These data suggest that patients with GC high risk might benefit from more nodal imaging and treatment intensification, potentially via pelvic nodal dissection, pelvic nodal irradiation, and/or the addition of chemohormonal agents.

PATIENT SUMMARY

Patients with higher genomic classifier scores were found to have more metastatic lymph node involvement on prostate-specific membrane antigen imaging.

PIWI-interacting RNA-36712 restrains breast cancer progression and chemoresistance by interaction with SEPW1 pseudogene SEPW1P RNA

Background

Breast cancer is one of the most common malignancies and the major cause of cancer-related death in women. Although the importance of PIWI-interacting RNAs (piRNAs) in cancer has been increasingly recognized, few studies have been explored the functional mechanism of piRNAs in breast cancer development and progression.

Methods

We examined the top 20 highly expressed piRNAs based on the analysis of TCGA breast cancer data in two patient cohorts to test the roles of piRNAs in breast cancer. The effects of piRNA-36,712 on the malignant phenotypes and chemosensitivity of breast cancer cells were detected in vitro and in vivo. MS2-RIP and reporter gene assays were conducted to identify the interaction and regulation among piRNA-36,712, miRNAs and SEPW1P. Kaplan-Meier estimate with log-rank test was used to compare patient survival by different piRNA-36,712 expression levels.

Results

We found piRNA-36,712 level was significantly lower in breast cancer than in normal breast tissues and low level was correlated with poor clinical outcome in patients. Functional studies demonstrated that piRNA-36,712 interacts with RNAs produced by SEPW1P, a retroprocessed pseudogene of SEPW1, and subsequently inhibits SEPW1 expression through competition of SEPW1 mRNA with SEPW1P RNA for microRNA-7 and microRNA-324. We also found that higher SEPW1 expression due to downregulation of piRNA-36,712 in breast cancer may suppress P53, leading to the upregulated Slug but decreased P21 and E-cadherin levels, thus promoting cancer cell proliferation, invasion and migration. Furthermore, we found that piRNA-36,712 had synergistic anticancer effects with the paclitaxel and doxorubicin, two chemotherapeutic agents for breast cancer.

Conclusions

These findings suggest that piRNA-36,712 is a novel tumor suppressor and may serve as a potential predictor for the prognosis of breast cancer patients.

Electronic supplementary material

The online version of this article (10.1186/s12943-019-0940-3) contains supplementary material, which is available to authorized users.

Evaluation of the Incidence of Hematologic Malignant Neoplasms Among Breast Cancer Survivors in France

IMPORTANCE

Breast cancer survivors are at an increased risk of developing certain types of hematologic malignant neoplasm after diagnosis.

OBJECTIVE

To estimate the incidence of various types of hematologic malignant neoplasm in breast cancer survivors, both in absolute terms and in association with the general population.

DESIGN, SETTING, AND PARTICIPANTS

This nationwide cohort study conducted in France used data from the French National Health Data System, a database that contains all of French residents' health-related expenses. All French women aged 20 to 85 years with an incident breast cancer diagnosis between July 1, 2006, and December 31, 2015, were included (n = 439 704) and followed up until hematologic malignant neoplasm occurrence, death, loss of follow-up, or December 31, 2016, whichever came first. Comparisons were made with all French women in the general population who were registered in the French general health insurance program each year from January 1, 2007, and December 31, 2016. Data analysis was performed from January 23, 2018, to May 25, 2018.

MAIN OUTCOMES AND MEASURES

Main outcomes were incident hematologic malignant neoplasm cases occurring at least 6 months after breast cancer diagnosis. The various types of hematologic malignant neoplasm considered were acute myeloid leukemia (AML), myelodysplastic syndrome (MDS), myeloproliferative neoplasms (MPNs), multiple myeloma (MM), Hodgkin lymphoma or non-Hodgkin lymphoma (HL/NHL), and acute lymphoblastic leukemia or lymphocytic lymphoma (ALL/LL). Incidence of these various types was estimated among breast cancer survivors and compared with the incidence in women in the general population.

RESULTS

The 439 704 women in the study had a median (interquartile range [IQR]) age of 59 (50-69) years and were followed up for a median (IQR) duration of 5 (2.8-7.5) years. Overall, 3046 cases of hematologic malignant neoplasm occurred: 509 cases (16.7%) of AML (crude incidence rate [CIR] per 100 000 person-years, 24.5; 95% CI, 22.4-26.8), 832 cases (27.3%) of MDS (CIR, 40.1; 95% CI, 37.4-42.9), and 267 cases (8.8%) of MPN (CIR, 12.8; 95% CI, 11.4-14.5). Lymphoid neoplasm cases included 420 cases (13.8%) of MM (CIR, 20.3; 95% CI, 18.4-22.3), 912 cases (29.9%) of HL/NHL (CIR, 44.4; 95% CI, 41.1-50.0), and 106 cases (3.5%) of ALL/LL (CIR, 5.1; 95% CI, 4.2-6.2). Compared with the general population, breast cancer survivors had statistically significantly higher incidence of AML (standardized incidence rate ratio [SIRR], 2.8; 95% CI, 2.5-3.2) and MDS (SIRR, 5.0; 95% CI, 4.4-5.7) and, to a lesser extent, MM (SIRR, 1.5; 95% CI, 1.3-1.7]) and ALL/LL (SIRR, 2.0; 95% CI, 1.3-3.0).

CONCLUSIONS AND RELEVANCE

The finding that AML and MDS still occur among breast cancer survivors today, and that ALL/LL and MM may also be of concern, merits the continuous monitoring of hematologic malignant neoplasms and the thorough investigations into their underlying mechanisms.

Patient-centered simulations to assess the usefulness of the 70-gene signature for adjuvant chemotherapy administration in early-stage breast cancer

PURPOSE

From the MINDACT trial, Cardoso et al. did not demonstrate a significant efficacy for adjuvant chemotherapy (CT) for women with early-stage breast cancer presenting high clinical and low genomic risks. Our objective was to assess the usefulness of the 70-gene signature in this population by using an alternative endpoint: the number of Quality-Adjusted Life-Years (QALYs), i.e., a synthetic measure of quantity and quality of life.

METHODS

Based on the results of the MINDACT trial, we simulated a randomized clinical trial consisting of 1497 women with early-stage breast cancer presenting high clinical and low genomic risks. The individual preferences for the different health states and corresponding decrements were obtained from the literature.

RESULTS

The gain in terms of 5-year disease-free survival was 2.8% (95% CI from - 0.1 to 5.7%, from 90.4% for women without CT to 93.3% for women with CT). In contrast, due to the associated side effects, CT significantly reduced the number of QALYs by 62 days (95% CI from 55 to 70 days, from 4.13 years for women without CT to 3.96 years for women with CT).

CONCLUSION

Our results support the conclusions published by Cardoso et al. by providing additional evidence that the 70-gene signature can be used to avoid overtreatment by CT for women with high clinical risk but low genomic risk.

SEOM clinical guidelines in early stage breast cancer (2018)

Breast cancer is the most common cancer in women in our country and it is usually diagnosed in the early and potentially curable stages. Nevertheless, around 20-30% of patients will relapse despite appropriate locoregional and systemic therapies. A better knowledge of this disease is improving our ability to select the most appropriate therapy for each patient with a recent diagnosis of an early stage breast cancer, minimizing unnecessary toxicities and improving long-term efficacy.

Risk stratification in early breast cancer in premenopausal and postmenopausal women: integrating genomic assays with clinicopathological features

PURPOSE OF REVIEW

There is growing consensus that genomic assays provide useful complementary information to clinicopathological features in oestrogen receptor-positive breast cancers. Here, ongoing research with multigene tests used for postmenopausal breast cancer and new emerging prognostic and predictive markers for pre and postmenopausal women are summarised.

RECENT FINDINGS

Results of the TAILORx trial have shown that women with an intermediate risk score do not benefit from adjuvant chemotherapy. Prosgina has been further investigated in a contemporary patient population in postmenopausal women and its use has been extended for premenopausal women. The EndoPredict was extensively used in decision-impact studies showing that its use can potentially reduce the need for adjuvant chemotherapy. Several new genomic assays have been developed, with some of them showing promising use for women with early oestrogen receptor-positive breast cancer.

SUMMARY

New areas of research for prediction of recurrence and risk stratification involve the development of immune gene signatures that carry modest but significant prognostic value. The recent expansion of high-throughput technology platforms including circulating tumour DNA/RNA and microRNA offer new opportunities to improve prediction models, particularly in women with oestrogen receptor-negative disease and premenopausal women. Genomic assays have clearly improved prognostication of early oestrogen receptor-positive breast cancer but it is clear that standard clinicopathological parameters are still very important when identifying patient for adjuvant chemotherapy.

The association of socioeconomic status with receipt of neoadjuvant chemotherapy

BACKGROUND

There are advantages to neoadjuvant chemotherapy in operable breast cancer, particularly for those with higher-risk cancers, but little is known about factors that are associated with the use of neoadjuvant chemotherapy outside of clinical trials. We examined whether use of neoadjuvant chemotherapy instead of adjuvant chemotherapy varies by nonclinical factors such as patient socioeconomic status or rural residence.

METHODS

Women diagnosed with breast cancer in 2013-2014 at eight medical institutions were surveyed by mail regarding their experiences with breast cancer treatment, and this information was linked to hospital-based cancer registries. We examined the use of neoadjuvant chemotherapy among women with histologically confirmed invasive stage I-III breast cancer and used regression models to examine the association of socioeconomic status with chemotherapy timing. We also explored potential mechanisms for those differences.

RESULTS

Over 29% of the chemotherapy sample overall received neoadjuvant chemotherapy. Neoadjuvant receipt was lower for those with income < $100,000 (AOR 0.56, 95% CI 0.2-0.9) even with adjustment for other demographics, stage, and biomarker status, and findings for education and a variable for both lowest education and income < $100,000 were similar. Rural/urban residence was not associated with neoadjuvant receipt. Differences by income in perceptions of the importance of neoadjuvant chemotherapy advantages and disadvantages did not appear to explain the differences in use by income.

CONCLUSIONS

In a multicenter sample of breast cancer patients, lower income was strongly associated with less receipt of neoadjuvant chemotherapy. Since patients with lower socioeconomic status are more likely to present with later-stage disease, this pattern has the potential to contribute to breast cancer outcome disparities.

Identification of risk in cutaneous melanoma patients: Prognostic and predictive markers

New therapeutic modalities for melanoma promise benefit in selected individuals. Efficacy appears greater in patients with lower tumor burden, suggesting an important role for risk-stratified surveillance. Robust predictive markers might permit optimization of agent to patient, while low-risk prognostic markers might guide more conservative management. This review evaluates protein, gene, and multiplexed marker panels that may contribute to better risk assessment and improved management of patients with cutaneous melanoma.

21-Gene Recurrence Score Testing in HER2-positive Patients

INTRODUCTION

The 21-gene recurrence score (RS) has been extensively studied and validated in patients with estrogen receptor-positive (ER⁺), human epidermal growth factor 2 (HER2)-negative breast cancer; however, RS testing is not routinely performed in patients with HER2-positive (HER2⁺) disease. We sought to determine patterns of RS testing, to characterize RS distributions, and to determine the impact of RS results on clinical decision-making for patients with ER⁺, HER2⁺ breast cancer.

MATERIALS AND METHODS

Using the Surveillance and Epidemiology End Results program database, we identified women with ER⁺, HER2⁺ breast cancer. We stratified patients using TAILORx RS cutoffs and evaluated treatment characteristics across patients. Multivariable logistic regression was performed to determine factors associated with RS testing and receipt of a high-risk RS.

RESULTS

Overall, 5% of patients with ER⁺, HER2⁺, early stage breast cancer underwent RS testing. The distribution of RS testing by TAILORx cutoffs were: high-risk, 17%; intermediate-risk, 49%; and low-risk, 34%. Chemotherapy utilization among those not tested was 66%. Among those tested, utilization was significantly associated with RS results: 67% of high-risk, 30% of intermediate-risk, and 19% of low-risk patients received chemotherapy. Progesterone receptor-negative status, larger tumor size, and high tumor grade were significantly associated with high-risk RS.

CONCLUSIONS

RS testing is used sparingly among patients with HER2⁺ early-stage breast cancer; however, test results appear to impact clinician's decision-making on chemotherapy use.

Postmastectomy radiation therapy for triple negative, node-negative breast cancer

PURPOSE

The use of post-mastectomy radiation therapy (PMRT) for patients with node-negative, triple negative breast cancer (TNBC) is controversial. This study of a large, contemporary US database described national practice patterns and addressed the impact of PMRT on survival for patients with node-negative TNBC.

METHODS

The National Cancer Data Base was queried (2004-2014) for women with non-metastatic TNBC with pT1-4N0M0 disease undergoing mastectomy. Use of PMRT was assessed. Multivariable logistic regression ascertained factors associated with PMRT use. The Kaplan-Meier analysis evaluated overall survival (OS) between patients managed with either PMRT or observation following mastectomy when stratifying by pT stage. Cox proportional hazards modeling determined variables associated with OS.

RESULTS

A total of 14,464 patients met the selection criteria; of these, 1,569 (10.8%) received PMRT, whereas 12,895 (89.2%) did not receive PMRT. Use of PMRT varied significantly with pT stage, with only 5.7% of T1 patients undergoing PMRT, while 51.6% of patients with T3 disease underwent PMRT. Use of PMRT was associated with superior OS for patients with pT3 disease but not for patients with other T stages. Greater age was associated with decreased likelihood of PMRT use, while increased T stage and positive surgical margins were associated with use of PMRT. On multivariate analysis, increased age, T stage, and positive surgical margins were associated with worse OS.

CONCLUSIONS

In the largest study to date evaluating the use of PMRT in patients with node-negative TNBC, the use of PMRT was low in patients with T1 and T2 disease. Additionally, while an OS benefit was observed with the use of PMRT in patients with T3 disease, there was no benefit with the use of PMRT in other T stage groups. Further prospective studies are recommended to further elucidate the benefit on PMRT in patients with node-negative TNBC.

BCL-2 expression aids in the immunohistochemical prediction of the Oncotype DX breast cancer recurrence score

Background

The development of molecular techniques to estimate the risk of breast cancer recurrence has been a significant addition to the suite of tools available to pathologists and breast oncologists. It has previously been shown that immunohistochemistry can provide a surrogate measure of tumor recurrence risk, effectively providing a less expensive and more rapid estimate of risk without the need for send-out. However, concordance between gene expression-based and immunohistochemistry-based approaches has been modest, making it difficult to determine when one approach can serve as an adequate substitute for the other. We investigated whether immunohistochemistry-based methods can be augmented to provide a useful therapeutic indicator of risk.

Methods

We studied whether the Oncotype DX breast cancer recurrence score can be predicted from routinely acquired immunohistochemistry of breast tumor histology. We examined the effects of two modifications to conventional scoring measures based on ER, PR, Ki-67, and Her2 expression. First, we tested a mathematical transformation that produces a more diagnostic-relevant representation of the staining attributes of these markers. Second, we considered the expression of BCL-2, a complex involved in regulating apoptosis, as an additional prognostic marker.

Results

We found that the mathematical transformation improved concordance rates over the conventional scoring model. By establishing a measure of prediction certainty, we discovered that the difference in concordance between methods was even greater among the most certain cases in the sample, demonstrating the utility of an accompanying measure of prediction certainty. Including BCL-2 expression in the scoring model increased the number of breast cancer cases in the cohort that were considered high certainty, effectively expanding the applicability of this technique to a greater proportion of patients.

Conclusions

Our results demonstrate an improvement in concordance between immunohistochemistry-based and gene expression-based methods to predict breast cancer recurrence risk following two simple modifications to the conventional scoring model.

OncotypeDX Recurrence Score Does Not Predict Nodal Burden in Clinically Node Negative Breast Cancer Patients

BACKGROUND

OncotypeDX recurrence score (RS)^® has been found to predict recurrence and disease-free survival in patients with node negative breast cancer. Whether RS is useful in guiding locoregional therapy decisions is unclear. We sought to evaluate the relationship between RS and lymph node burden.

METHODS

Patients with invasive breast cancer who underwent sentinel lymph node dissection from 2010 to 2015 were identified from a prospectively maintained database. Patients were excluded if they were clinically node positive or if they received neoadjuvant chemotherapy. RS was classified as low (< 18), intermediate (18-30), or high (> 30). The association between RS, lymph node burden, and disease recurrence was evaluated. Statistical analyses were performed in R version 3.4.0; p < 0.05 was considered significant.

RESULTS

A positive SLN was found in 168 (15%) of 1121 patients. Completion axillary lymph node dissection was performed in 84 (50%) of SLN-positive patients. The remaining 84 (50%) patients had one to two positive SLNs and did not undergo further axillary surgery. RS was low in 58.5%, intermediate in 32.6%, and high in 8.9%. RS was not associated with a positive SLN, number of positive nodes, maximum node metastasis size, or extranodal extension. The median follow-up was 23 months. High RS was not associated with locoregional recurrence (p = 0.07) but was significantly associated with distant recurrence (p = 0.0015).

CONCLUSIONS

OncotypeDX RS is not associated with nodal burden in women with clinically node-negative breast cancer, suggesting that RS is not useful to guide decisions regarding extent of axillary surgery for these patients.

The Distribution and Outcomes of the 21-Gene Recurrence Score in T1-T2N0 Estrogen Receptor-Positive Breast Cancer With Different Histologic Subtypes

Background: The clinical value of 21-gene recurrence score (RS) in various breast cancer histologic subtypes is not well established.

Aims: To assess the distribution and outcomes of the 21-gene RS among various T1-T2N0 estrogen receptor-positive breast cancer histologic subtypes.

Methods: Using the Surveillance, Epidemiology and End Results database, we investigated the distribution and outcomes of the 21-gene RS among various breast cancer histologic subtypes between 2004 and 2015. The histologic subtypes with 200 or more cases were further analyzed.

Results: We identified 83,665 patients including eight histologic subtypes. The most common subtype was invasive ductal carcinoma not otherwise specified (IDC NOS) (77.9%), followed by lobular carcinoma NOS, mixed infiltrating duct and lobular carcinoma (IDC-L), mucinous adenocarcinoma, tubular adenocarcinoma, micropapillary ductal carcinoma, cribriform carcinoma NOS, and intraductal papillary adenocarcinoma with invasion with 10.8, 7.7, 2.1, 0.6, 0.3, 0.2, and 0.2%, respectively. The 5-years breast cancer specific survival (BCSS) was 98.8, 98.8, 98.9, 99.6, 100, 100, 100, and 100%, respectively (P = 0.011). Patients with IDC NOS (8.9%), micropapillary ductal carcinoma (8.8%), and intraductal papillary adenocarcinoma with invasion (8.2%) had significantly higher percentage of high-risk RS compared to other histologic subtypes (1.0–3.8%) (P < 0.001). The mean RS was higher in IDC NOS, lobular carcinoma NOS, and IDC-L compared to other subtypes. In multivariate analysis, 21-gene RS was the independent prognostic factor in patients with IDC NOS (P < 0.001), lobular carcinoma NOS (P < 0.001), and IDC-L (P < 0.001), patients with a higher RS was associated with poor BCSS.

Conclusion: Our results demonstrate that there is a significant difference in distribution of 21-gene RS in T1-T2N0 estrogen receptor-positive breast cancer with different histologic subtypes. Long-term studies with larger series are needed to confirm the role of the 21-gene RS array in prognosis assessment and chemotherapy decision-making in special histologic subtypes with favorable prognosis.

Update Breast Cancer 2018 (Part 3) - Genomics, Individualized Medicine and Immune Therapies - in the Middle of a New Era: Prevention and Treatment Strategies for Early Breast Cancer

In primary early breast cancer, the aim of treatment planning is to obtain an increasingly better understanding of the disease. The identification of patients with an excellent prognosis could help this group avoid unnecessary treatments. Furthermore, the planning of treatment is becoming increasingly patient-focussed. There is a growing understanding of those patients who benefit particularly from chemotherapy, as well as of those who could benefit from immunotherapy. Studies conducted on immunotherapies will be published shortly. Smaller individual studies offer an initial insight into the efficacy of checkpoint inhibitors (anti-PD1/PDL1 therapies). Not least, one of the largest breast cancer studies of all times has recently come to an end. The use of a multigene test has shown that it is sufficient to identify patients with such a good prognosis that chemotherapy is unnecessary. This review article is intended to summarise the current studies and give an outlook on current developments.

Anthracycline and taxane-based chemotherapy versus docetaxel and cyclophosphamide in the adjuvant treatment of HER2-negative breast cancer patients: a systematic review and meta-analysis of randomized controlled trials

PURPOSE

Standard adjuvant chemotherapy for HER2-negative breast cancer consists generally in an anthracycline and taxane-based regimen (A+T). The TC (docetaxel and cyclophosphamide) regimen arises as a potential alternative, although individual randomized controlled trials (RCTs) could not demonstrate the non-inferiority of TC over A+T. This is a systematic review and meta-analysis of RCTs comparing 6 cycles of TC versus sequential A+T in the adjuvant treatment of HER2-negative breast cancer.

METHODS

A systematic literature search was performed to identify RCTs comparing TC versus A+T. Disease-free survival (DFS) and overall survival (OS) were assessed. Subgroup analyses of DFS according to hormone receptor status, lymph node involvement, and menopausal status were performed. Hazard ratios (HRs) and 95% confidence intervals (CI) for DFS and OS were extracted from each trial, and a pooled analysis was conducted using the random-effect model. The Higgins' I-Squared Test was used to quantify heterogeneity.

RESULTS

Seven RCTs were included (12,741 patients). Overall, no difference was observed between TC and A+T in DFS (HR 1.08, 95% CI 0.96-1.20) and OS (HR 1.05; 95% CI 0.90-1.22). A trend favoring A+T was observed in hormone receptor-negative (HR 1.12, 95% CI 0.93-1.34) and N2 patients (HR 1.25; 95% CI 0.82-1.90). Emesis/vomiting, mucositis, thrombocytopenia and sensory neuropathy were significantly more frequent with A+T.

CONCLUSION

As adjuvant treatment of HER2-negative breast cancer, sequential A+T regimen was associated with increased risk of toxicities and no clear survival benefit as compared to 6 cycles of TC. Higher-risk patients may benefit the most from A+T, whilst TC may be an efficacious and less toxic alternative for lower-risk patients.

Gene expression profiling in melanoma: past results and future potential

The field of melanoma oncology is rapidly evolving with advances in detection, staging and treatment. There is heterogeneity in all stages of melanoma where some patients fare better than others for reasons currently unknown and it is sometimes unclear which patients warrant closer surveillance, multidisciplinary care, increased imaging, more aggressive surgery or adjuvant therapy. Early studies have shown the predictive ability of gene expression profiling (GEP) and institutions that have adopted GEP for melanoma treatment have demonstrated changes in practice patterns and patient management. The goal of this paper is to review the clinical evidence for a new diagnostic test, DecisionDx-Melanoma, the only GEP test for cutaneous melanoma with prospective studies analyzing its utility.

Moving Breast Cancer Therapy up a Notch

Breast cancer is the second most common malignancy, worldwide. Treatment decisions are based on tumor stage, histological subtype, and receptor expression and include combinations of surgery, radiotherapy, and systemic treatment. These, together with earlier diagnosis, have resulted in increased survival. However, initial treatment efficacy cannot be guaranteed upfront, and these treatments may come with (long-term) serious adverse effects, negatively affecting a patient's quality of life. Gene expression-based tests can accurately estimate the risk of recurrence in early stage breast cancers. Disease recurrence correlates with treatment resistance, creating a major need to resensitize tumors to treatment. Notch signaling is frequently deregulated in cancer and is involved in treatment resistance. Preclinical research has already identified many combinatory therapeutic options where Notch involvement enhances the effectiveness of radiotherapy, chemotherapy or targeted therapies for breast cancer. However, the benefit of targeting Notch has remained clinically inconclusive. In this review, we summarize the current knowledge on targeting the Notch pathway to enhance current treatments for breast cancer and to combat treatment resistance. Furthermore, we propose mechanisms to further exploit Notch-based therapeutics in the treatment of breast cancer.

The Prognostic Significance of the Oncotype DX Recurrence Score in T1-2N1M0 Estrogen Receptor-Positive HER2-Negative Breast Cancer Based on the Prognostic Stage in the Updated AJCC 8th Edition

BACKGROUND

This study aimed to evaluate the prognostic significance of the Oncotype DX recurrence score (RS) in T_1-2N₁M₀ estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-negative breast cancer based on the prognostic stage in the updated American Joint Commission on Cancer, 8th edition.

METHODS

The Surveillance, Epidemiology, and End Results database was searched to identify ER-positive invasive ductal breast cancer in T_1-2N₁M₀ with RS results diagnosed between 2004 and 2012. Patients with RS were categorized into low-risk (RS < 11), intermediate-risk (RS 11-25), and high-risk (RS > 25) groups. The distributions of clinical-pathological characteristics were compared among the RS risk groups using Pearson's Chi square. Breast cancer-specific survival (BCSS) and overall survival (OS) were estimated using the Kaplan-Meier method and compared across RS groups using the log-rank statistic. Cox models were fitted to assess the factors independently associated with survival.

RESULTS

The study enrolled 4059 cases categorized into prognostic stages IA to IIB. The RS risk groups were positively correlated with pathological prognostic stages (P < 0.001). The RS risk groups differed significantly in terms of BCSS and OS (P < 0.001). According to the multivariate analysis, RS risk group was an independent prognostic factor for BCSS and OS together with the pathological prognostic stage. The subgroup analysis showed similar survival rates across pathological prognostic stages in the RS low-risk group but significant differences in survival rates among pathological prognostic stages in the RS intermediate-risk group. The survival rates among the RS risk groups also differed significantly in pathological prognostic stage IA.

CONCLUSIONS

Oncotype DX RS provided independent prognostic significance to complement the prognostic staging system.

21-Gene assay as predictor of chemotherapy benefit in HER2-negative breast cancer

The NSABP B-20 prospective-retrospective study of the 21-gene Oncotype DX Breast Cancer Recurrence Score® test predicted benefit from addition of chemotherapy to tamoxifen in node-negative, estrogen-receptor positive breast cancer when recurrence score (RS) was ≥31. HER2 is a component of the RS algorithm with a positive coefficient and contributes to higher RS values. Accrual to B-20 occurred prior to routine testing for HER2, so questions have arisen regarding assay performance if HER2-positive patients were identified and excluded. We report an exploratory reanalysis of the B-20, 21-gene study following exclusion of such patients. Patients were considered HER2 positive if quantitative RT-PCR for HER2 was ≥11.5 units, and excluded from re-analyses performed using the original cutoffs: <18, 18–30, ≥31, and the TAILORx cutoffs: <11, 11–25, >25. The endpoint remained distant recurrence-free interval (DRFI) as in the original study. Distribution was estimated via the Kaplan–Meier method and compared via log-rank test. Multivariate Cox proportional hazards models estimated chemotherapy benefit in each group. In the RS < 18 and 18–30 groups, 1.7 and 6.7% were HER2 positive. In the RS ≥ 31 group, 41% were HER2 positive. Exclusion resulted in fewer events, with loss of significance for benefit from chemotherapy in the overall HER2-negative cohort (log-rank P = 0.06), but substantial benefit from chemotherapy remained in the RS ≥ 31 cohort (HR = 0.18; 95% CI: 0.07–0.47) and the RS > 25 cohort (HR = 0.28; 95% CI: 0.12–0.64). No benefit from chemotherapy was evident in the other RS groups. Following exclusion of HER2-positive patients based on RT-PCR expression, substantial benefit of chemotherapy remained for RS ≥ 31 as originally employed, and with RS > 25 employed in TAILORx.

A commonly used genetic test helps to predict whether patients with estrogen-receptor positive, node-negative breast cancer stand to gain from chemotherapy. Charles Geyer from NRG Oncology/NSABP and Virginia Commonwealth University and colleagues reanalyzed data from a decades-old study that helped establish a 21-gene panel as a tool for determining whether to add chemotherapy to endocrine therapy for women with estrogen-receptor positive, node-negative breast cancer. The researchers excluded patients with HER2-positive disease because HER2 gene expression is part of the diagnostic test and questions have persisted regarding the performance of the assay, if HER2-positive patients were excluded. This new analysis demonstrated that although chemotherapy did not extend disease-free survival overall among the cohort of patients with HER2-negative disease, it still proved beneficial for those with high recurrence scores on the genetic test. The findings thus validate the clinical utility of the test for patients with estrogen-receptor positive, HER2-negative, node negative breast cancers.

Management of young women with early breast cancer

Breast cancer is still the most frequent cancer diagnosed in women aged ≤40 years and the primary cause of death in this age group. The management of these patients needs a dedicated approach involving a multidisciplinary team that takes into account their treatment and survivorship issues. The present review aims to provide a perspective on the many challenges associated with treatment of young women with early breast cancer. We will focus on the standard (neo)adjuvant treatment, highlighting the paucity of age-specific results about the available genomic signatures, the groundbreaking landscape of adjuvant endocrine therapy and the relevant issue of the fertility preservation.

Optimizing multi-modal cancer treatment under 3D spatio-temporal tumor growth

In this paper we introduce a new mixed-integer linear programming (MIP) model that explicitly integrates the spread of cancer cells into a spatio-temporal reaction-diffusion (RD) model of cancer growth, while taking into account treatment effects. This linear but non-convex model appears to be the first of its kind by determining the optimal sequence of the typically prescribed cancer treatment methods-surgery (S), chemotherapy (C), and radiotherapy (R)-while minimizing the newly generated tumor cells for early-stage breast cancer in a unique three-dimensional (3D) spatio-temporal system. The quadratically-constrained cancer growth dynamics and treatment impact formulations are linearized by using linearization as well as approximation techniques. Under the supervision of medical oncologists and utilizing several literature resources for the parameter values, the effectiveness of treatment combinations for breast cancer specified with different sequences (i.e., SRC, SCR, CR, RC) are compared by tracking the number of cancer cells at the end of each treatment modality. Our results provide the optimal dosages for chemotherapy and radiation treatments, while minimizing the growth of new cancer cells.

Community clinical practice patterns and mortality in patients with intermediate oncotype DX recurrence scores: Who benefits from chemotherapy?

BACKGROUND

The Oncotype DX recurrence score (RS) is used as a tool for making decisions about chemotherapy for patients who have hormone receptor (estrogen receptor or progesterone receptor)-positive, HER2-negative breast cancer. There is no benefit from chemotherapy among patients aged ≥50 years who have lymph node-negative disease and an RS from 11 to 25, but the benefit of chemotherapy in the lymph node-positive group remains unknown.

METHODS

On the basis of data from the National Cancer Data Base between 2010 and 2014, a nationwide, retrospective cohort study included 73,185 women who had stage I through IIIA breast cancer and an RS between 11 and 30.

RESULTS

Receipt of chemotherapy was associated with a reduced risk of death among patients who had lymph node-positive breast cancer (hazard ratio [HR] 0.58; 95% confidence interval [CI], 0.45-0.74; P < .001) after adjusting for other prognostic factors in a multivariable Cox model. The 5-year survival gain ranged from 1.3% (RS 11-17 subgroup), to 3.3% (RS 18-25 subgroup), and to 6.7% (RS 26-30 subgroup). Among patients who had lymph node-negative disease, chemotherapy was associated with a reduced risk of death for those with an RS from 25 to 30 (HR, 0.68; 95% CI, 0.48-0.96; P = .03; 5-year survival gain, 1.8%), but there was no benefit from chemotherapy for patients who had an RS from 11 to 17 (HR, 0.97; 95% CI, 0.61-1.55; P = .90), and there was a marginally significant benefit for women who had an RS from 18 to 25 (HR, 0.79; 95% CI, 0.62-1.00; P = .05). Similar results were observed using propensity score-matching method.

CONCLUSIONS

The benefit of chemotherapy for patients with breast cancer who have an intermediate RS is driven in a nonlinear fashion by RS: the higher the RS, the larger the absolute benefit. Findings from this study underscore the utility of real-world data to inform joint decision making in practice.

Online accounts of gene expression profiling in early-stage breast cancer: Interpreting genomic testing for chemotherapy decision making

Background

Genomic techniques are being developed within oncology and beginning to be experienced within routine cancer care. Little is known about how these tools feature in patients’ experiences of treatment decision making.

Objective

This research explores the ways in which women interpret and discuss gene expression profiling for breast cancer treatment decision making, as articulated within online accounts.

Design

This study used a qualitative approach to analyse written exchanges focusing on gene expression profiling in the UK (Oncotype DX test). Accounts are taken from online forums hosted by two UK cancer charity websites, comprising 132 discussion threads from a total of seven forums. Authors qualitatively analysed the data and developed key themes drawing on existing literature from medical sociology.

Findings

Women used online spaces to share and discuss results of gene expression profiling. Women interpreted results in the context of indirect experience of cancer treatment, and sociocultural depictions of cancer and chemotherapy. Users largely represented the test positively, emphasizing its ability to “personalize” treatment pathways, though many also pointed to inherent uncertainties with regards the possibility of cancer recurrence.

Discussion and Conclusions

We highlight the complex contexts in which genomic techniques are experienced, with these shaped by personal biographies, online environments and pervasive cultural narratives of cancer and its treatment. We highlight tensions between the claims of genomic testing to aid treatment decision making and patient reflections on the capability of these techniques to resolve uncertainties surrounding treatment decisions.

Impact of 21-Gene Expression Assay on Staging Estrogen Receptor-Positive HER2-Negative Breast Cancer

PURPOSE

The 8th edition of the American Joint Committee on Cancer (AJCC) breast cancer staging system requires histologic grade (GR), estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), and stage (assessed by the tumor, node, metastasis classification system). For T1-2 N0, ER⁺/HER2- tumors, if the 21-gene expression assay is ordered and Oncotype DX (ODX) recurrence score (RS) is 0 to 10, the stage is IA. The purpose of this study was to determine the impact of the ODXRS on staging ER⁺/HER2- tumors.

MATERIALS AND METHODS

This is a retrospective review of ER⁺/HER2- invasive breast cancer (BC) with ODXRS results from 2 institutions (n = 816) between 2006 and 2018. Stage based on the AJCC 7th and 8th editions, and stage using the 8th edition with and without ODXRS were compared. Significant associations among pathologic parameters and ODX risk groups were determined. Clinical histories were reviewed.

RESULTS

Nearly half of the patients (43%) had a change in BC stage using the new staging system. Only 4 patients changed stage as a direct result of ODXRS. Influence of ODXRS on staging is limited to T2N0 tumors that are either GR 3 and strongly ER⁺ and PR⁺ or GR 1-2 and ER⁺/PR-. Sixty-one percent of cases of recurrence (11/18) were downstaged using the new staging system.

CONCLUSION

ODXRS has little influence on staging, thus supporting the view of the AJCC 8th edition expert panel that ODX is not required for staging. Downstaging of more than half of cases of recurrence suggests that continued refinement of the staging system, as proposed by the expert panel, could be beneficial in this subgroup of patients.

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.

Multifocal/Multicentric Ipsilateral Invasive Breast Carcinomas with Similar Histology: Is Multigene Testing of All Individual Foci Necessary?

BACKGROUND

Multiple synchronous ipsilateral invasive breast carcinomas (BCs) with similar histology usually have concordant receptor status. It is unknown whether individual foci with similar histology also share molecular and biological similarities or are heterogenous. This study examined the concordance of the 21-gene recurrence score (RS) in multiple synchronous morphologically similar ipsilateral BCs.

PATIENTS AND METHODS

We identified patients with multiple ipsilateral BCs and available RS treated at our institution from 1/2014 to 6/2018. BCs were divided into three groups based on RS: (1) RS in same risk category, (2) RS in different risk categories but within 2-unit difference (e.g., RS 17 and RS 19), and (3) RS in different risk categories and a change of > 2 units. BCs in groups 1 and 2 were considered as concordant (no significant clinical impact) and BCs in group 3 as discordant (variation affects management).

RESULTS

A total of 53 patients met the study criteria. RS was concordant in 46 (87%) cases. Seven (13%) cases were discordant (group 3). Of these, three (43%, 3/7) had biopsy cavity changes (BXC) adjacent to the BC with highest RS. In two cases the focus with higher RS had a lower percentage of progesterone receptor-positive tumor cells. In two cases, extensive ductal carcinoma in situ was associated with the BC focus with lower RS.

CONCLUSIONS

Morphologically similar multifocal ipsilateral BCs have concordant RS in 87% (46/53) of cases. Our results suggest that, in cases of morphologically similar multifocal BCs, testing of a single focus provides accurate prognostic and predictive information.