Race, Gene Expression Signatures, and Clinical Outcomes of Patients With High-Risk Early Breast Cancer

Importance

There has been little consideration of genomic risk of recurrence by breast cancer subtype despite evidence of racial disparities in breast cancer outcomes.

Objective

To evaluate associations between clinical trial end points, namely pathologic complete response (pCR) and distant recurrence-free survival (DRFS), and race and examine whether gene expression signatures are associated with outcomes by race.

Design, Setting, and Participants

This retrospective cohort study used data from the Investigation of Serial Studies to Predict Your Therapeutic Response With Imaging and Molecular Analysis 2 (I-SPY 2) multicenter clinical trial of neoadjuvant chemotherapy with novel agents and combinations for patients with previously untreated stage II/III breast cancer. Analyses were conducted of associations between race and short- and long-term outcomes, overall and by receptor subtypes, and their association with 28 expression biomarkers. The trial enrolled 990 female patients between March 30, 2010, and November 5, 2016, with a primary tumor size of 2.5 cm or greater and clinical or molecular high risk based on MammaPrint or hormone receptor (HR)-negative/ERBB2 (formerly HER2 or HER2/neu)-positive subtyping across 9 arms. This data analysis was performed between June 10, 2021, and October 20, 2022.

Exposure

Race, tumor receptor subtypes, and genomic biomarker expression of early breast cancer.

Main Outcomes and Measures

The primary outcomes were pCR and DRFS assessed by race, overall, and by tumor subtype using logistic regression and Cox proportional hazards regression models. The interaction between 28 expression biomarkers and race, considering pCR and DRFS overall and within subtypes, was also evaluated.

Results

The analytic sample included 974 participants (excluding 16 self-reporting as American Indian or Alaska Native, Native Hawaiian or Other Pacific Islander, or multiple races due to small sample sizes), including 68 Asian (7%), 120 Black (12%), and 786 White (81%) patients. Median (range) age at diagnosis was 47 (25-71) years for Asian, 49 (25-77) for Black, and 49 (23-73) years for White patients. The pCR rates were 32% (n = 22) for Asian, 30% for Black (n = 36), and 32% for White (n = 255) patients (P = .87). Black patients with HR-positive/ERBB2-negative tumors not achieving pCR had significantly worse DRFS than their White counterparts (hazard ratio, 2.28; 95% CI, 1.24-4.21; P = .01), with 5-year DRFS rates of 55% (n = 32) and 77% (n = 247), respectively. Black patients with HR-positive/ERBB2-negative tumors, compared with White patients, had higher expression of an interferon signature (mean [SD], 0.39 [0.87] and -0.10 [0.99]; P = .007) and, compared with Asian patients, had a higher mitotic score (mean [SD], 0.07 [1.08] and -0.69 [1.06]; P = .01) and lower estrogen receptor/progesterone receptor signature (mean [SD], 0.31 [0.90] and 1.08 [0.95]; P = .008). A transforming growth factor β signature had a significant association with race relative to pCR and DRFS, with a higher signature associated with lower pCR and worse DRFS outcomes among Black patients only.

Conclusions and Relevance

The findings show that women with early high-risk breast cancer who achieve pCR have similarly good outcomes regardless of race, but Black women with HR-positive/ERBB2-negative tumors without pCR may have worse DRFS than White women, highlighting the need to develop and test novel biomarker-informed therapies in diverse populations.

Evaluation of Alisertib Alone or Combined With Fulvestrant in Patients With Endocrine-Resistant Advanced Breast Cancer: The Phase 2 TBCRC041 Randomized Clinical Trial

Importance

Aurora A kinase (AURKA) activation, related in part to AURKA amplification and variants, is associated with downregulation of estrogen receptor (ER) α expression, endocrine resistance, and implicated in cyclin-dependent kinase 4/6 inhibitor (CDK 4/6i) resistance. Alisertib, a selective AURKA inhibitor, upregulates ERα and restores endocrine sensitivity in preclinical metastatic breast cancer (MBC) models. The safety and preliminary efficacy of alisertib was demonstrated in early-phase trials; however, its activity in CDK 4/6i-resistant MBC is unknown.

Objective

To assess the effect of adding fulvestrant to alisertib on objective tumor response rates (ORRs) in endocrine-resistant MBC.

Design, Setting, and Participants

This phase 2 randomized clinical trial was conducted through the Translational Breast Cancer Research Consortium, which enrolled participants from July 2017 to November 2019. Postmenopausal women with endocrine-resistant, ERBB2 (formerly HER2)-negative MBC who were previously treated with fulvestrant were eligible. Stratification factors included prior treatment with CDK 4/6i, baseline metastatic tumor ERα level measurement (<10%, ≥10%), and primary or secondary endocrine resistance. Among 114 preregistered patients, 96 (84.2%) registered and 91 (79.8%) were evaluable for the primary end point. Data analysis began after January 10, 2022.

Interventions

Alisertib, 50 mg, oral, daily on days 1 to 3, 8 to 10, and 15 to 17 of a 28-day cycle (arm 1) or alisertib same dose/schedule with standard-dose fulvestrant (arm 2).

Main Outcomes and Measures

Improvement in ORR in arm 2 of at least 20% greater than arm 1 when the expected ORR for arm 1 was 20%.

Results

All 91 evaluable patients (mean [SD] age, 58.5 [11.3] years; 1 American Indian/Alaskan Native [1.1%], 2 Asian [2.2%], 6 Black/African American [6.6%], 5 Hispanic [5.5%], and 79 [86.8%] White individuals; arm 1, 46 [50.5%]; arm 2, 45 [49.5%]) had received prior treatment with CDK 4/6i. The ORR was 19.6%; (90% CI, 10.6%-31.7%) for arm 1 and 20.0% (90% CI, 10.9%-32.3%) for arm 2. In arm 1, the 24-week clinical benefit rate and median progression-free survival time were 41.3% (90% CI, 29.0%-54.5%) and 5.6 months (95% CI, 3.9-10.0), respectively, and in arm 2 they were 28.9% (90% CI, 18.0%-42.0%) and 5.4 months (95% CI, 3.9-7.8), respectively. The most common grade 3 or higher adverse events attributed to alisertib were neutropenia (41.8%) and anemia (13.2%). Reasons for discontinuing treatment were disease progression (arm 1, 38 [82.6%]; arm 2, 31 [68.9%]) and toxic effects or refusal (arm 1, 5 [10.9%]; arm 2, 12 [26.7%]).

Conclusions and Relevance

This randomized clinical trial found that adding fulvestrant to treatment with alisertib did not increase ORR or PFS; however, promising clinical activity was observed with alisertib monotherapy among patients with endocrine-resistant and CDK 4/6i-resistant MBC. The overall safety profile was tolerable.

Trial Registration

ClinicalTrials.gov Identifier: NCT02860000.

Use of 18F-FDG PET/CT as an Initial Staging Procedure for Stage II-III Breast Cancer: A Multicenter Value Analysis

BACKGROUND

Metastatic staging imaging is not recommended for asymptomatic patients with stage I-II breast cancer. Greater distant metastatic disease risk may warrant baseline imaging in patients with stage II-III with high-risk biologic subtypes. NCCN Guidelines recommend considering CT of the chest, abdomen, and pelvis (CT CAP) and bone scan in appropriate patients. CT CAP and bone scan are considered standard of care (SoC), although PET/CT is a patient-centered alternative.

METHODS

Data were available for 799 high-risk patients with clinical stage II-III disease who initiated screening for the I-SPY2 trial at 4 institutions. A total of 564 complete records were reviewed to compare PET/CT versus SoC. Costs were determined from the payer perspective using the national 2018 Medicare Physician Fee Schedule and representative reimbursements to the University of California, San Francisco (UCSF). Incremental cost-effectiveness ratio (ICER) measured cost of using PET/CT per percent of patients who avoided a false-positive (FP).

RESULTS

The de novo metastatic disease rate was 4.6%. Imaging varied across the 4 institutions (P<.0001). The FP rate was higher using SoC versus PET/CT (22.1% vs 11.1%; P=.0009). Mean time between incidental finding on baseline imaging to FP determination was 10.8 days. Mean time from diagnosis to chemotherapy initiation was 44.3 days with SoC versus 37.5 days with PET/CT (P=.0001). Mean cost per patient was $1,132 (SoC) versus $1,477 (PET/CT) using the Medicare Physician Fee Schedule, with an ICER of $31. Using representative reimbursements to UCSF, mean cost per patient was $1,236 (SoC) versus $1,073 (PET/CT) for Medicare, and $3,083 (SoC) versus $1,656 (PET/CT) for a private payer, with ICERs of -$15 and -$130, respectively.

CONCLUSIONS

Considerable variation exists in metastatic staging practices. PET/CT reduced FP risk by half and decreased workup of incidental findings, allowing for earlier treatment start. PET/CT may be cost-effective, and at one institution was shown to be cost-saving. Better alignment is needed between hospital pricing strategies and payer coverage policies to deliver high-value care.

Management of Hereditary Breast Cancer: American Society of Clinical Oncology, American Society for Radiation Oncology, and Society of Surgical Oncology Guideline

PURPOSE

To develop recommendations for management of patients with breast cancer (BC) with germline mutations in BC susceptibility genes.

METHODS

The American Society of Clinical Oncology, American Society for Radiation Oncology, and Society of Surgical Oncology convened an Expert Panel to develop recommendations based on a systematic review of the literature and a formal consensus process.

RESULTS

Fifty-eight articles met eligibility criteria and formed the evidentiary basis for the local therapy recommendations; six randomized controlled trials of systemic therapy met eligibility criteria.

RECOMMENDATIONS

Patients with newly diagnosed BC and BRCA1/2 mutations may be considered for breast-conserving therapy (BCT), with local control of the index cancer similar to that of noncarriers. The significant risk of a contralateral BC (CBC), especially in young women, and the higher risk of new cancers in the ipsilateral breast warrant discussion of bilateral mastectomy. Patients with mutations in moderate-risk genes should be offered BCT. For women with mutations in BRCA1/2 or moderate-penetrance genes who are eligible for mastectomy, nipple-sparing mastectomy is a reasonable approach. There is no evidence of increased toxicity or CBC events from radiation exposure in BRCA1/2 carriers. Radiation therapy should not be withheld in ATM carriers. For patients with germline TP53 mutations, mastectomy is advised; radiation therapy is contraindicated except in those with significant risk of locoregional recurrence. Platinum agents are recommended versus taxanes to treat advanced BC in BRCA carriers. In the adjuvant/neoadjuvant setting, data do not support the routine addition of platinum to anthracycline- and taxane-based chemotherapy. Poly (ADP-ribose) polymerase (PARP) inhibitors (olaparib and talazoparib) are preferable to nonplatinum single-agent chemotherapy for treatment of advanced BC in BRCA1/2 carriers. Data are insufficient to recommend PARP inhibitor use in the early setting or in moderate-penetrance carriers. Additional information available at www.asco.org/breast-cancer-guidelines.

Abstract P5-10-06: Race associated disparities in an urban population of adolescent and young adult (AYA) women with breast cancer

Introduction: Although only about 5-7% of breast cancers occur in women under 40 years of age, multiple studies have shown that these cancers are more aggressive. In addition issues related to genetic testing and fertility preservation are of particular importance for AYA patients with breast cancer. This retrospective analysis aims to describe various biologic and treatment related factors of an urban AYA population with breast cancer and the differences amongst these factors stratified by African American (AA) versus non-AA race. We will look at factors including stage at diagnosis, hormone receptor status, prevalence of BRCA1/2 mutations, time from diagnosis to treatment, enrollment in clinical trials, and fertility preservation.

Methods: A retrospective study of a population of AYA women with breast cancer seen at two hospitals in Washington D.C. from 2006 to 2015 was performed. Data was collected on age, BRCA1/2 test results, stage at diagnosis, hormone receptor status, time from diagnosis to treatment, enrollment in clinical trial, fertility preservation, and pregnant or breastfeeding status at time of diagnosis. Fisher exact test was used to test the association between two categorical variables. Wilcoxon rank sum test was used to compare time to treatment and stage at presentation between AA and non-AA patients.

Results: A total of 161 AYA patients were evaluated. 54 were identified as AA and 107 as non-AA (88 Caucasians, 13 Asian, 6 Hispanics). Median age was 32 years (20-39) overall; 32 years (23-39) for AA and 33 years (20-39) for non-AA. While the rate of genetic testing was high, significantly fewer AA AYA underwent testing compared to non-AA (74% versus 87% respectively, (p=0.050)) and 10% of AA versus 22% of non-AA were found to have a BRCA1/2 deleterious mutation (p=NS). Clinical trial participation was lower for AA compared to non-AA (57% vs. 76%, p=NS) for those where clinical trials were discussed/offered. Fertility preservation was pursued by 10% of AA vs. 35% of non-AA (p=0.001). Of note, 61% of AA and 34% of non-AA had children at the time of diagnosis (p=0.001). While AA (31%) presented more often with advanced stages of cancer compared to non-AA (19%) this was not statistically significant. Triple negativity was similar in AA AYA (25%) vs. non-AA (22%). The median time to treatment initiation did not vary between AA and non-AA (37 days vs. 36 days, p=NS).

Conclusion: In this retrospective study of an urban population of AYA women with breast cancer, there were no delays in treatment initiation or significant differences between AA and non-AA. When compared to non-AA, AA had a statistically significant lower rate of genetic testing and fertility preservation, although the latest could have been affected by a higher number of nulliparous in non-AA. . Encouragingly, the clinical trial participation of AYA who had previously discussed clinical trials with their physician was very high.

Citation Format: Chitalia AA, Aqbal D, Yin R, Cai L, Isaacs CJ, Lynce FC. Race associated disparities in an urban population of adolescent and young adult (AYA) women with breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P5-10-06.

Prediagnostic Sex Steroid Hormones in Relation to Male Breast Cancer Risk

PURPOSE

Although previous studies have implicated a variety of hormone-related risk factors in the etiology of male breast cancers, no previous studies have examined the effects of endogenous hormones.

PATIENTS AND METHODS

Within the Male Breast Cancer Pooling Project, an international consortium comprising 21 case-control and cohort investigations, a subset of seven prospective cohort studies were able to contribute prediagnostic serum or plasma samples for hormone quantitation. Using a nested case-control design, multivariable unconditional logistic regression analyses estimated odds ratios and 95% CIs for associations between male breast cancer risk and 11 individual estrogens and androgens, as well as selected ratios of these analytes.

RESULTS

Data from 101 cases and 217 matched controls were analyzed. After adjustment for age and date of blood draw, race, and body mass index, androgens were found to be largely unrelated to risk, but circulating estradiol levels showed a significant association. Men in the highest quartile had an odds ratio of 2.47 (95% CI, 1.10 to 5.58) compared with those in the lowest quartile (trend P = .06). Assessment of estradiol as a ratio to various individual androgens or sum of androgens showed no further enhancement of risk. These relations were not significantly modified by either age or body mass index, although estradiol was slightly more strongly related to breast cancers occurring among younger (age < 67 years) than older men.

CONCLUSION

Our results support the notion of an important role for estradiol in the etiology of male breast cancers, similar to female breast cancers.

Association of Rad51 polymorphism with DNA repair in BRCA1 mutation carriers and sporadic breast cancer risk

BACKGROUND

Inter-individual variation in DNA repair capacity is thought to modulate breast cancer risk. The phenotypic mutagen sensitivity assay (MSA) measures DNA strand breaks in lymphocytes; women with familial and sporadic breast cancers have a higher mean number of breaks per cell (MBPC) than women without breast cancer. Here, we explore the relationships between the MSA and the Rad51 gene, which encodes a DNA repair enzyme that interacts with BRCA1 and BRCA2, in BRCA1 mutation carriers and women with sporadic breast cancer.

METHODS

Peripheral blood lymphoblasts from women with known BRCA1 mutations underwent the MSA (n = 138 among 20 families). BRCA1 and Rad51 genotyping and sequencing were performed to identify SNPs and haplotypes associated with the MSA. Positive associations from the study in high-risk families were subsequently examined in a population-based case-control study of breast cancer (n = 1170 cases and 2115 controls).

RESULTS

Breast cancer diagnosis was significantly associated with the MSA among women from BRCA1 families (OR = 3.2 95%CI: 1.5-6.7; p = 0.004). The Rad51 5'UTR 135 C>G genotype (OR = 3.64; 95% CI: 1.38, 9.54; p = 0.02), one BRCA1 haplotype (p = 0.03) and in a polygenic model, the E1038G and Q356R BRCA1 SNPs were significantly associated with MBPC (p = 0.009 and 0.002, respectively). The Rad51 5'UTR 135C genotype was not associated with breast cancer risk in the population-based study.

CONCLUSIONS

Mutagen sensitivity might be a useful biomarker of penetrance among women with BRCA1 mutations because the MSA phenotype is partially explained by genetic variants in BRCA1 and Rad51.

Hormone replacement therapy in women with a history of breast carcinoma

Hormone replacement therapy in women with a history of successfully treated breast cancer is felt to be contraindicated. Very little direct information is available regarding the effect of such therapy in this patient population. This article reviews the evidence both supporting and refuting a causative role for estrogen and progesterone in breast cancer. The majority of evidence supports such a role. The use of tamoxifen as an alternative treatment modality is examined.