The PARTNER trial of neoadjuvant olaparib in triple-negative breast cancer

PARTNER is a prospective, phase II-III, randomised controlled clinical trial, which recruited patients with Triple Negative Breast Cancer (TNBC)1,2, who were gBRCA wild type (gBRCAwt)3. Patients (n=559) were randomised on a 1:1 basis to neoadjuvant carboplatin with paclitaxel +/- olaparib 150mg twice daily, days 3 to 14, for 4 cycles (gap schedule olaparib, research arm) followed by 3 cycles of anthracycline chemotherapy before surgery. The primary endpoint was pathological complete response (pCR)4, and secondary endpoints included event-free survival (EFS), and overall survival (OS)5. pCR was achieved in 51% in the research arm and 52% in the control arm (p=0.753). Estimated EFS at 36 months in research and control arms were 80% and 79% (log-rank p>0.9); OS were 90% and 87.2% (log-rank p=0.8) respectively. In patients with pCR, estimated EFS at 36 months was 90%, and with non-pCR was 70% (log-rank p < 0.001) and OS was 96% and 83% (log-rank p < 0.001) respectively. Neo-adjuvant olaparib did not improve pCR rates, EFS or OS when added to carboplatin/paclitaxel and anthracycline chemotherapy in patients with TNBC (gBRCAwt). This is in marked contrast to the major benefit of olaparib (gap schedule) in those with gBRCA pathogenic variants (gBRCAm) which is reported separately (gBRCAm article). ClinicalTrials.gov ID NCT03150576.

Genomic analysis of early-stage lung cancer reveals a role for TP53 mutations in distant metastasis

Patients with non-small cell lung cancer (NSCLC) who have distant metastases have a poor prognosis. To determine which genomic factors of the primary tumor are associated with metastasis, we analyzed data from 759 patients originally diagnosed with stage I-III NSCLC as part of the AACR Project GENIE Biopharma Collaborative consortium. We found that TP53 mutations were significantly associated with the development of new distant metastases. TP53 mutations were also more prevalent in patients with a history of smoking, suggesting that these patients may be at increased risk for distant metastasis. Our results suggest that additional investigation of the optimal management of patients with early-stage NSCLC harboring TP53 mutations at diagnosis is warranted in light of their higher likelihood of developing new distant metastases.

Precision Breast Cancer Medicine: Early Stage Triple Negative Breast Cancer-A Review of Molecular Characterisation, Therapeutic Targets and Future Trends

Personalised approaches to the management of all solid tumours are increasing rapidly, along with wider accessibility for clinicians. Advances in tumour characterisation and targeted therapies have placed triple-negative breast cancers (TNBC) at the forefront of this approach. TNBC is a highly heterogeneous disease with various histopathological features and is driven by distinct molecular alterations. The ability to tailor individualised and effective treatments for each patient is of particular importance in this group due to the high risk of distant recurrence and death. The mainstay of treatment across all subtypes of TNBC has historically been cytotoxic chemotherapy, which is often associated with off-target tissue toxicity and drug resistance. Neoadjuvant chemotherapy is commonly used as it allows close monitoring of early treatment response and provides valuable prognostic information. Patients who achieve a complete pathological response after neoadjuvant chemotherapy are known to have significantly improved long-term outcomes. Conversely, poor responders face a higher risk of relapse and death. The identification of those subgroups that are more likely to benefit from breakthroughs in the personalised approach is a challenge of the current era where several targeted therapies are available. This review presents an overview of contemporary practice, and promising future trends in the management of early TNBC. Platinum chemotherapy, DNA damage response (DDR) inhibitors, immune checkpoint inhibitors, inhibitors of the PI3K-AKT-mTOR, and androgen receptor (AR) pathways are some of the increasingly studied therapies which will be reviewed. We will also discuss the growing evidence for less-developed agents and predictive biomarkers that are likely to contribute to the forthcoming advances in this field. Finally, we will propose a framework for the personalised management of TNBC based upon the integration of clinico-pathological and molecular features to ensure that long-term outcomes are optimised.

Association Between ABCB1 Genetic Variants and Persistent Chemotherapy-Induced Alopecia in Women With Breast Cancer

Importance

Persistent chemotherapy-induced alopecia (pCIA) has been recently described in patients with breast cancer and in its most severe form occurs in up to 10% of these patients. Genetic risk factors associated with pCIA have not been adequately explored.

Objective

To identify genetic variants associated with pCIA.

Design, Setting, and Participants

In this genetic association study, 215 women with breast cancer treated with docetaxel-based chemotherapy with a follow-up of 1.5 to 10 years after the end of the treatment were recruited retrospectively through 3 hospital oncology units across Spain between 2005 and 2018. Severe pCIA was defined as lack of scalp hair recovery (Common Terminology Criteria for Adverse Events, version 3.0, grade 2) 18 months or more after the end of treatment. Patients with grade 2 pCIA were selected as cases, and those with no sign of residual alopecia 12 months after the end of docetaxel treatment were selected as controls. A genome-wide association study in a discovery phase was conducted, and logistic regression was used to identify variants associated with the risk to develop this adverse effect. The validity of the association was addressed through a replication phase.

Exposures

Docetaxel-based chemotherapy.

Main Outcomes and Measures

Genotypes of single-nucleotide variants associated with pCIA.

Results

In total, 215 women with breast cancer (median age, 51.6 years; interquartile range, 44-60 years) were recruited (173 patients for the discovery phase and 42 patients for the replication phase). In the discovery phase, ABCB1 genetic variants were associated with risk to develop pCIA. In particular, single-nucleotide variation rs1202179, a regulatory variant located in an enhancer element that interacts with the ABCB1 promoter, was associated with the occurrence of pCIA. This finding was validated in the replication cohort (combined odds ratio, 4.05; 95% CI, 2.46-6.67; P = 3.946 × 10-8). This variant is associated with ABCB1 mRNA expression, and the risk allele was associated with decreased ABCB1 expression levels (P = 1.64 × 10-20).

Conclusions and Relevance

This is the first study, to our knowledge, that identifies an association between a regulatory variant in the ABCB1 gene and the occurrence of pCIA in patients with breast cancer who were treated with docetaxel-based therapies. This finding suggests an important insight into the biological mechanisms underlying pCIA and opens the opportunity to explore personalized treatment of these patients.

Abstract OT3-01-02: PARTNERING / PARTNER : Phase II sub-study to establish if the addition of combinations of new agents (olaparib, cell cycle and immune checkpoint inhibitors) can improve the rate of pathological complete response (pCR) and minimal residual disease (MRD) in triple negative breast cancer (TNBC) and / or germline BRCA mutated (gBRCAm) patients with evidence of residual disease after PARTNER therapy

Background:

In patients with TNBC, following standard neoadjuvant chemotherapy, residual disease (RD) is correlated with poor prognosis and 50% relapse within 5 years [1]. PARTNER is a neoadjuvant clinical trial which randomises TNBC and gBRCAm patients to carboplatin and paclitaxel +/- olaparib followed by anthracycline-based chemotherapy. Patients with RD after neoadjuvant treatment in this trial also face poorer survival outcomes, due to the paucity of treatment options. PARTNERING, develops a new strategy using novel agent combinations as an alternative pathway for patients with RD within the PARTNER trial.

Methods: PARTNERING is a phase II open label, sub-study with a two-stage Simon design with biomarker guided treatment cohorts open only to patients in the PARTNER trial. A maximum of 15 patients will be included in each cohort. Patients with RD &gt; 10% tumour cellularity (TC) on biopsy after neoadjuvant therapy will be eligible. Patients who have no tumour cells or &lt; 10% TC, and those with progressive disease will be excluded. Allocation of patients into the cohorts will be based on tumour infiltrating lymphocytes (TILs) expression either on diagnostic or post treatment biopsy. Patients with tumours with TILs score ≤20% are considered “non-immunogenic” They will be stratified according to HRD status and allocated to receive a cell cycle checkpoint inhibitor + olaparib. Patients with a TILs score &gt;20% are considered “immunogenic” and will be allocated to receive an immune checkpoint inhibitor with olaparib or a cell cycle checkpoint inhibitor.

Primary outcome measure is pCR / MRD rate at surgery after the administration of 2 cycles / 8 weeks of a combination of new agents. The rate of conversion to pCR/MRD will be correlated with TC, TILs, BRCA and homologous recombination deficiency (HRD) status, Ki67% and previous olaparib treatment.

Progress: The PARTNERING pathway in the PARTNER trial will be open late 2018.

Citation Format: Abraham JE, Vallier A-L, Qian W, Machin A, Grybowicz L, Thomas S, Weiss M, Harvey C, McAdam K, Hughes-Davies L, Roberts A, Provenzano E, Pinilla K, Roylance R, Copson E, Armstrong A, McMurtry E, Tischkowitz M, Earl HM. PARTNERING / PARTNER : Phase II sub-study to establish if the addition of combinations of new agents (olaparib, cell cycle and immune checkpoint inhibitors) can improve the rate of pathological complete response (pCR) and minimal residual disease (MRD) in triple negative breast cancer (TNBC) and / or germline BRCA mutated (gBRCAm) patients with evidence of residual disease after PARTNER therapy [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT3-01-02.

Abstract OT3-03-03: PARTNER: Randomised, phase II/III trial to evaluate the safety and efficacy of the addition of olaparib to platinum-based neoadjuvant chemotherapy in triple negative and/or germline BRCA mutated breast cancer patients

Background: No specific targeted therapies are available for Triple Negative Breast Cancers (TNBC), an aggressive and diverse subgroup. The basal TNBC sub-group share some phenotypic and molecular similarities with germline BRCA (gBRCA) tumours. In gBRCA patients, and potentially other homologous recombination deficiencies, these already compromised pathways may allow drugs called PARP inhibitors (Olaparib) to work more effectively. Aims: To establish if the addition of olaparib to neoadjuvant platinum based chemotherapy for basal TNBC and/or gBRCA breast cancer is safe and improves efficacy (pathological complete response (pCR)).

Methods: Trial design: 3-stage open label randomised phase II/III trial of neoadjuvant paclitaxel and carboplatin +/- olaparib, followed by clinicians' choice of anthracycline regimen. Stage 1 and 2: Randomisation (1:1:1) to either control (3 weekly carboplatin AUC5/weekly paclitaxel 80mg/m2 for 4 cycles) or one of two research arms with the same chemotherapy regimen but with two different schedules of olaparib 150mg BD for 12 days. Stage 3: Patients are randomised (1:1) to either control arm or to the research arm selected in stage 2. End-points: Stage 1: Safety; Stage 2: Schedule selection using pCR rate and completion rate of olaparib using a “pick-the-winner” design. Stage 3: pCR rate. Enrichment design is applied with an overall significance level 0.05(α) and 80% power. A total of 527 patients will be included to detect an absolute improvement of 15% (all patients) and 20% (gBRCA patients) by adding olaparib to platinum based chemotherapy.

Trial Progress: PARTNER has been recruiting in UK since 27th May 2016. IDSMC recommended to continue the trial without change after reviewing the Stage 1 safety data. The recruitment of stage 2 was completed in April 2018 and results to be reviewed by the IDSMC in early 2019. The trial is open and enrolling patients to national and international sites.

Citation Format: Abraham J, Vallier A-L, Qian W, Machin A, Grybowicz L, Thomas S, Weiss M, Harvey C, McAdam K, Hughes-Davies L, Roberts A, Roylance R, Copson E, Pinilla K, Armstrong A, Provenzano E, Tischkowitz M, McMurty E, Earl H. PARTNER: Randomised, phase II/III trial to evaluate the safety and efficacy of the addition of olaparib to platinum-based neoadjuvant chemotherapy in triple negative and/or germline BRCA mutated breast cancer patients [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT3-03-03.

Persistent major alopecia following adjuvant docetaxel for breast cancer: incidence, characteristics, and prevention with scalp cooling

Background

Persistent alopecia (PA) after docetaxel has been recently described. The aim of our study is to establish the incidence and characteristics of PA following adjuvant docetaxel for breast cancer (BC) and to test the ability of scalp cooling in prevention.

Patients and methods

BC patients receiving adjuvant chemotherapy followed or not by endocrine therapy (and a control group receiving only endocrine therapy) were interviewed in a single institution at 1.5 to 5 years following primary diagnosis searching for PA. A confirmatory prevalence study was later performed in other two institutions. Finally, a prevention study using prophylactic scalp cooling (PSC) with ELASTO-GEL hypothermia caps in patients receiving adjuvant docetaxel was performed.

Results

In the initial prevalence study (492 patients), minor forms of PA (grade 1) were recorded with all chemotherapy regimens and aromatase inhibitors. Patients receiving docetaxel regimens at cumulative dose (CD) ≥ 400 mmg/m² presented a significantly higher prevalence of grades 1 PA (33–52%) and 2 PA (5–12%). Prevalence of grade 2 PA with docetaxel CD ≥ 400 mmg/m² was confirmed in two other institutions. Overall, grade 2 PA was seen in 10.06% (95% CI 7.36–13.61) of 358 patients with docetaxel regimens reaching CD ≥ 400 mmg/m², but not in patients with lower docetaxel CD, other chemotherapy regimens, or endocrine therapy alone. In prevention trial, no grade 2 PA occurred among 116 patients receiving adjuvant docetaxel (≥ 400 mmg/m²) and PSC followed-up after a 96 months median time. PSC was well tolerated. No scalp relapses were seen among 30 patients (22% of all inclusions) having disease relapse.

Conclusion

Adjuvant treatment with docetaxel (CD ≥ 400 mmg/m²) is associated with a significant rate of grade 2 PA, leading to wearing a wig, in around 10% of patients. This toxicity was completely prevented with scalp cooling. Clinical Trial Reference: NCT00515762.

Electronic supplementary material

The online version of this article (10.1007/s10549-018-4855-2) contains supplementary material, which is available to authorized users.

Abstract P1-14-12: Validation of residual cancer burden index (RCB) as a prognostic tool in patients with early breast cancer (EBC) treated with neoadjuvant chemotherapy (NAC): Comparison of RCB and Miller & Payne system (M&P)

Pathological evaluation of response after NAC is a controversial issue. M&P has been for years the most widely employed score. Recently RCB index, a new system including axillary evaluation, seems to improve prognostic discrimination.

PURPOSE: The aim of this study was to validate the RCB index as a method to define prognosis in a reallife cohort of EBC patients treated with NAC and compare it to M&P system.

METHODS: We performed a retrospective analysis of our database. Patients with stage I-III considered candidate for NAC between January 2003 and August 2011 were included. RCB and M&P were calculated as previously published. Hormone receptor expression (RH), and Her2 were assessed following international guidelines. The Harell c-index and Roc curves were used to compare the prognostic value of RCB and M&P. Clinical, therapeutic and pathological data were obtained from medical records. A correlation with disease-free survival (DFS) and overall survival (OS) was done using the Kaplan-Meier method and Cox regression model.

RESULTS: 333 patients were included in this study. Distribution of breast cancer subtypes was: luminal 50.9%, Her2+ 31% and triple negative 18.1%. Mean tumour size was 42.3 mm. The majority of the patients had histhological grade II-III tumours (87.3%), with N stage 0-1 (97.3%). 87.4% received anthracycline and taxane-based NAC, associated to trastuzumab in her 2+ patients. Pathological complete response was 14% for the global population, being 30% for TN and 21.3% Her2+ subtypes. With a median follow-up of 56.3 months, DFS and OS at 5 years were as follows: RCB-0 93.6% and 97.9%, RCB-I 84.2% and 98.2%, RCB-II 79.1% and 89.5%, RCB-III 38.3% and 63.6%. Harell c-index value of RCB was statistically superior to M&P in both DFS (0.80 vs 0.68, p= 0.001) and OS (0.87 vs 0.69, p&lt;0.001 ). This superiority value of RCB was consistent among all breast cancer subtypes.

CONCLUSION: RCB index is as more accurated prognostic score to predict DFS and OS compared to M&P.

Citation Format: Pons V, BurguÉs O, PÉrez-Fidalgo JA, MartÍnez MT, Pinilla K, Bermejo B, Lluch A. Validation of residual cancer burden index (RCB) as a prognostic tool in patients with early breast cancer (EBC) treated with neoadjuvant chemotherapy (NAC): Comparison of RCB and Miller & Payne system (M&P). [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P1-14-12.