Clinical Outcomes, Treatment Patterns, and Health Resource Utilization Among Metastatic Breast Cancer Patients with Germline BRCA1/2 Mutation: A Real-World Retrospective Study

Efficacy of front-line treatment for hormone receptor-positive HER2-negative metastatic breast cancer with germline BRCA1/2 mutation

BACKGROUND

Efficacy of endocrine therapy in HR+/HER2- metastatic breast cancer could differ depending on the presence of BRCA1/2 germline mutation.

METHODS

The ESME metastatic breast cancer platform (NCT03275311) is a French real world database. Multivariable models including a time-varying approach and landmark analyses assessed the association between time-dependent gBRCA status (categorised as gBRCAm, gBRCAwt (wild type), and untested), overall survival (OS), and first-line progression-free survival (PFS1).

RESULTS

A total of 170 patients were gBRCAm carriers, 676 gBRCAwt, and 12,930 were untested at baseline. In the multivariable analysis, gBRCAm carriers overall had a lower OS compared to gBRCAwt (adjusted HR [95% CI] 1.26 [1.03-1.55]). gBRCAm patients treated with front-line endocrine therapy had lower adjusted OS (adjusted HR [95% CI] = 1.54 [1.03-2.32]) and PFS1 (adjusted HR [95% CI] 1.58 [1.17-2.12]) compared to gBRCAwt patients. However, for patients who received frontline chemotherapy, neither OS nor PFS1 differed between gBRCAm carriers and the other groups (HR versus gBRCAwt for OS: 1.12 [0.88-1.41], p = 0.350; PFS1: 1.09 [0.90-1.31], p = 0.379).

CONCLUSION

In this large cohort of HR+/HER2- MBC patients treated in a pre-CDK4/6 inhibitors era, gBRCAm status was associated with a lower OS and lower PFS following first-line endocrine therapy, but not following first-line chemotherapy.

Germline BRCA-Mutated HER2-Negative Advanced Breast Cancer: Overcoming Challenges in Genetic Testing and Clinical Considerations When Using Talazoparib

Genetic testing is essential to the diagnosis and management of patients with breast cancer. For example, women who carry mutations in BRCA1/2 genes have an increased lifetime risk of breast cancer and the presence of these mutations may sensitize the patient to treatment with poly(ADP-ribose) polymerase (PARP) inhibitors. Two PARP inhibitors are approved by the US Food and Drug Administration for patients with germline BRCA-mutated advanced breast cancer (olaparib and talazoparib). The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Breast Cancer (Version 2.2023) recommend that all patients with recurrent or metastatic breast cancer (mBC) be assessed for the presence of germline BRCA1/2 mutations. However, many women eligible for genetic testing do not receive it. Here, we provide our perspectives on both the importance of genetic testing and the challenges patients and community clinicians may face when trying to access genetic testing. We also present a hypothetical case study involving a female patient with germline BRCA-mutated human epidermal growth factor receptor 2 (HER2)-negative mBC to highlight potential clinical considerations on the use of talazoparib, including the decision to initiate therapy, dosing considerations, potential drug-drug interactions, and managing side effects. This case illustrates the benefits of a multidisciplinary approach to managing patients with mBC and involving the patient in the decision-making process. This patient case is fictional and does not represent events or a response from an actual patient; this fictional case is for educational purposes only.

Real-world clinical outcomes of patients with BRCA-mutated, human epidermal growth factor receptor 2 (HER2)-negative metastatic breast cancer: a CancerLinQ® study

Purpose

To investigate real-world clinical outcomes in patients with BRCA-mutated (BRCAm), HER2-negative metastatic breast cancer (mBC) according to BRCA and hormone receptor (HR) status.

Methods

Patients diagnosed with HER2-negative mBC between 01 January 2010 and 31 December 2018 were retrospectively identified from the American Society of Clinical Oncology’s CancerLinQ Discovery® database. Time to first subsequent therapy or death (TFST) from date of mBC diagnosis and start of first-line treatment for mBC and overall survival (OS) from date of mBC diagnosis were investigated according to BRCA status (BRCAm, BRCA wild type [BRCAwt] or unknown BRCA [BRCAu]) and HR status (positive/triple negative breast cancer [TNBC]). Follow-up continued until 31 August 2019 (i.e. minimum of 8 months).

Results

3744 patients with HER2-negative mBC were identified (BRCAwt, n = 460; BRCAm, n = 83; BRCAu, n = 3201) (HR-positive, n = 2738). Median (Q1, Q3) age was 63.0 (54.0, 73.0) years. Median (95% confidence interval [CI]) TFST (months) from mBC diagnosis was as follows: HR-positive, 7.7 (5.0, 11.2), 8.3 (6.6, 10.2) and 9.4 (8.7, 10.1); TNBC, 5.4 (3.9, 12.4), 5.6 (4.7, 6.6) and 5.4 (5.0, 6.2) for BRCAm, BRCAwt and BRCAu, respectively. Median (95% CI) OS (months) was as follows: HR-positive, 41.1 (31.5, not calculable), 55.1 (43.5, 65.5) and 33.0 (31.3, 34.8); TNBC, 13.7 (11.1, not calculable), 14.4 (10.7, 17.0) and 11.7 (10.3, 12.8) for BRCAm, BRCAwt and BRCAu, respectively.

Conclusion

When stratified by HR status, TFST and OS were broadly similar for patients with HER2-negative mBC, irrespective of BRCA status. Further global real-world studies are needed to study outcomes of this patient population.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10549-022-06541-3.

Real-world multi-country study of BRCA1/2 mutation testing among adult women with HER2-negative advanced breast cancer

Aim: We assessed real-world patient demographics and BRCA1/2 mutation testing rates among adult women with HER2-negative advanced breast cancer (ABC). Methods: Oncologists across the USA and in France, Germany, Italy, Spain and the UK provided medical chart data in 2015 and 2017. Results: Overall, 28% of patients received BRCA1/2 mutation testing. Untested patients were more likely to be aged ≥45 years, have hormone receptor-positive/HER2-negative ABC and have no known family history of breast/ovarian cancer. BRCA1/2 mutation testing rates were significantly lower in the European countries, women aged ≥45 years, women without a known family history of breast/ovarian cancer, and women with hormone receptor-positive/HER2-negative ABC versus advanced triple-negative breast cancer. Conclusion: BRCA1/2 mutation testing rates were low, and disparities were observed in patient characteristics among BRCA1/2 mutation-tested versus untested patients.

Trends in Use of Next-Generation Sequencing in Patients With Solid Tumors by Race and Ethnicity After Implementation of the Medicare National Coverage Determination

Importance

In March 2018, Medicare issued a national coverage determination (NCD) for next-generation sequencing (NGS) to facilitate access to NGS testing among Medicare beneficiaries. It is unknown whether the NCD affected health equity issues for Medicare beneficiaries and the overall population.

Objective

To examine the association between the Medicare NCD and NGS use by insurance types and race and ethnicity.

Design, Setting, and Participants

A retrospective cohort analysis was conducted using electronic health record data derived from a real-world database. Data originated from approximately 280 cancer clinics (approximately 800 sites of care) in the US. Patients with advanced non-small cell lung cancer (aNSCLC), metastatic colorectal cancer (mCRC), metastatic breast cancer (mBC), or advanced melanoma diagnosed from January 1, 2011, through March 31, 2020, were included.

Exposure

Pre- vs post-NCD period.

Main Outcomes and Measures

Patients were classified by insurance type and race and ethnicity to examine patterns in NGS testing less than or equal to 60 days after diagnosis. Difference-in-differences models examined changes in average NGS testing in the pre- and post-NCD periods by race and ethnicity, and interrupted time-series analysis examined whether trends over time varied by insurance type and race and ethnicity.

Results

Among 92 687 patients with aNSCLC, mCRC, mBC, or advanced melanoma, mean (SD) age was 66.6 (11.2) years, 51 582 (55.7%) were women, and 63 864 (68.9%) were Medicare beneficiaries. The largest racial and ethnic categories according to the database used and further classification were Black or African American (8605 [9.3%]) and non-Hispanic White (59 806 [64.5%]). Compared with Medicare beneficiaries, changes in pre- to post-NCD NGS testing trends were similar in commercially insured patients (odds ratio [OR], 1.03; 95% CI, 0.98-1.08; P = .25). Pre- to post-NCD NGS testing trends increased at a slower rate among patients in assistance programs (OR, 0.93; 95% CI, 0.87-0.99; P = .03) compared with Medicare beneficiaries. The rate of increase for patients receiving Medicaid was not statistically significantly different compared with those receiving Medicare (OR, 0.92; 95% CI, 0.84-1.01; P = .07). The NCD was not associated with statistically significant changes in NGS use trends by racial and ethnic groups within Medicare beneficiaries alone or across all insurance types. Compared with non-Hispanic White individuals, increases in average NGS use from the pre-NCD to post-NCD period were 14% lower (OR, 0.86; 95% CI, 0.74-0.99; P = .04) among African American and 23% lower (OR, 0.77; 95% CI, 0.62-0.96; P = .02) among Hispanic/Latino individuals; increases among Asian individuals and those with other races and ethnicities were similar.

Conclusions and Relevance

The findings of this study suggest that expansion of Medicare-covered benefits may not occur equally across insurance types, thereby further widening or maintaining disparities in NGS testing. Additional efforts beyond coverage policies are needed to ensure equitable access to the benefits of precision medicine.

Real-world Evidence of Diagnostic Testing and Treatment Patterns in US Patients With Breast Cancer With Implications for Treatment Biomarkers From RNA Sequencing Data

OBJECTIVE/BACKGROUND

We performed a retrospective analysis of longitudinal real-world data (RWD) from patients with breast cancer to replicate results from clinical studies and demonstrate the feasibility of generating real-world evidence. We also assessed the value of transcriptome profiling as a complementary tool for determining molecular subtypes.

METHODS

De-identified, longitudinal data were analyzed after abstraction from records of patients with breast cancer in the United States (US) structured and stored in the Tempus database. Demographics, clinical characteristics, molecular subtype, treatment history, and survival outcomes were assessed according to strict qualitative criteria. RNA sequencing and clinical data were used to predict molecular subtypes and signaling pathway enrichment.

RESULTS

The clinical abstraction cohort (n = 4000) mirrored the demographics and clinical characteristics of patients with breast cancer in the US, indicating feasibility for RWE generation. Among patients who were human epidermal growth factor receptor 2-positive (HER2+), 74.2% received anti-HER2 therapy, with ∼70% starting within 3 months of a positive test result. Most non-treated patients were early stage. In this RWD set, 31.7% of patients with HER2+ immunohistochemistry (IHC) had discordant fluorescence in situ hybridization results recorded. Among patients with multiple HER2 IHC results at diagnosis, 18.6% exhibited intra-test discordance. Through development of a whole-transcriptome model to predict IHC receptor status in the molecular sequenced cohort (n = 400), molecular subtypes were resolved for all patients (n = 36) with equivocal HER2 statuses from abstracted test results. Receptor-related signaling pathways were differentially enriched between clinical molecular subtypes.

CONCLUSIONS

RWD in the Tempus database mirrors the overall population of patients with breast cancer in the US. These results suggest that real-time, RWD analyses are feasible in a large, highly heterogeneous database. Furthermore, molecular data may aid deficiencies and discrepancies observed from breast cancer RWD.

A Real-World Evidence Study of CDK4/6 Inhibitor Treatment Patterns and Outcomes in Metastatic Breast Cancer by Germline BRCA Mutation Status

Introduction

Limited data exist on real-world treatment patterns and the effectiveness of cyclin-dependent kinase (CDK) 4/6 inhibitors in germline BRCA (gBRCA)-mutated breast cancer.

Methods

Adults with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2−) metastatic breast cancer (mBC) treated with CDK4/6 inhibitor therapy between 2013 and 2018 were retrospectively selected from the Flatiron Health database. Patients with known gBRCA status were classified as mutated (gBRCAm) or wild type (gBRCAwt). Time-to-first subsequent therapy or death (TFST) and overall survival (OS) were calculated from the earliest line of therapy with a CDK4/6 inhibitor.

Results

Of 2968 patients with HR+/HER2− mBC receiving a CDK4/6 inhibitor, 859 (28.9%) had known gBRCA status, of whom 9.9% were gBRCAm and 90.1% gBRCAwt. Median (95% confidence interval [CI]) TFST was 10 (7–11) months in the gBRCAm group, 10 (9–11) months in the gBRCAwt group, and 11 (10–12) months in the combined gBRCAwt and unknown gBRCA group; median (95% CI) OS was 26 (21–not estimated), 37 (31–51), and 33 (31–35) months, respectively. Cox models indicated the gBRCAm group had shorter TFST (stratified hazard ratio [sHR] 1.24; 95% CI 0.96–1.59) and OS (sHR 1.50; 95% CI 1.06–2.14) than the gBRCAwt group. The gBRCAm group had shorter TFST (sHR 1.38; 95% CI 1.08–1.75) and OS (sHR 1.22; 95% CI 0.88–1.71) than the combined group.

Conclusion

The results of this real-world study suggest that treatment outcomes with CDK4/6 inhibitors may be worse in patients with gBRCAm mBC than in their counterparts with gBRCAwt and unknown gBRCA status, suggesting potential differences in tumor biology. This result highlights the unmet need in patients with gBRCAm requiring optimized treatment selection and sequencing. Future exploration in larger samples of patients who have had biomarker testing is warranted.

Challenges and Opportunities for Real-World Evidence in Metastatic Luminal Breast Cancer

Background

The therapeutic armamentarium for patients with metastatic breast cancer is becoming more and more specific. Recommendations from clinical trials are not available for all treatment situations and patient subgroups, and it is therefore important to collect real-world data.

Summary

To develop recommendations for up-to-date treatments and participation in clinical trials for patients with metastatic breast cancer, the Prospective Academic Translational Research PRAEGNANT Network was established to optimize the quality of oncological care in the advanced therapeutic setting. The main aim of PRAEGNANT is to systematically record medical care for patients with metastatic breast cancer in the real-life setting, including the outcome and side effects of different treatment strategies, to monitor quality-of-life changes during therapy, to identify patients eligible for participation in clinical studies, and to allow targeted therapies based on the molecular structures of breast carcinomas.

Key Messages

This article describes the PRAEGNANT network and sheds light on the question of whether the various end points from clinical trials can be transferred to the real-world treatment situation.

Treatment patterns, health care resource use and outcomes in metastatic triple-negative breast cancer in Germany: retrospective chart review study (OBTAIN)

Background: There is limited data on the real-life situation and outcomes of patients with metastatic triple-negative breast cancer (mTNBC) in Germany. The aim of this chart review was to describe the current treatment patterns, resource use and outcomes in this patient group. Methods: Retrospective data collection in 30 gyneco-oncological sites (hospitals and office-based) across Germany between January and April 2017. Index date was defined as initiation of treatment with gemcitabine, vinorelbin, capecitabine or eribulin therapy following discontinuation of taxane and/or anthracycline therapy. Results: In the 91 evaluable patients, median time between primary diagnosis and index date was 20.9 months (range 0-187 months). Ten percent of patients had no distant metastases, while 57% had newly diagnosed metastases. Cancer stage at index date was mostly IV (82 patients). A number of 135 different regimens (monotherapy or combination therapy) were used. For first-line chemo treatment, 29 patients received monotherapy and 54 patients combination therapy. Bevacizumab and paclitaxel were also the most frequently used single substances among all therapy lines together and for first-line therapy. While taxanes were at least occasionally administered for second-line therapy, no patient received taxanes for third-line therapy. Chemotherapy modifications in terms of dose reduction or treatment interruption were rare. However, the therapy was terminated in more than two thirds of all cases. Fifty-nine patients were hospitalized at least once. For first-, second- and third-line therapy, median overall survival was 19.1/10.8/14.6 months, and median progression-free survival was 7.7/2.5/5.6 months. Conclusion: In clinical routine, a wide variety of treatment approaches is applied, while outcomes in terms of survival are poor. New treatment options are needed for this challenging tumor type.