Anthracycline-containing and taxane-containing chemotherapy for early-stage operable breast cancer: a patient-level meta-analysis of 100 000 women from 86 randomised trials

BACKGROUND

Anthracycline-taxane chemotherapy for early-stage breast cancer substantially improves survival compared with no chemotherapy. However, concerns about short-term and long-term side-effects of anthracyclines have led to increased use of taxane chemotherapy without anthracycline, which could compromise efficacy. We aimed to better characterise the benefits and risks of including anthracycline, and the comparative benefits of different anthracycline-taxane regimens.

METHODS

We did an individual patient-level meta-analysis of randomised trials comparing taxane regimens with versus without anthracycline, and updated our previous meta-analysis of anthracycline regimens with versus without taxane, as well as analysing 44 trials in six related comparisons. We searched databases, including MEDLINE, Embase, the Cochrane Library, and meeting abstracts to identify trials assessing anthracycline and taxane chemotherapy. Adjuvant or neoadjuvant trials were eligible if they began before Jan 1, 2012. Primary outcomes were breast cancer recurrence and cause-specific mortality. Log-rank analyses yielded first-event rate ratios (RRs) and CIs.

FINDINGS

28 trials of taxane regimens with or without anthracycline were identified, of which 23 were deemed eligible, and 15 provided data on 18 103 women. Across all 15 trials that provided individual data, recurrence rates were 14% lower on average (RR 0·86, 95% CI 0·79-0·93; p=0·0004) with taxane regimens including anthracycline than those without. Non-breast cancer deaths were not increased but there was one additional acute myeloid leukaemia case per 700 women treated. The clearest reductions in recurrence were found when anthracycline was added concurrently to docetaxel plus cyclophosphamide versus the same dose of docetaxel plus cyclophosphamide (10-year recurrence risk 12·3% vs 21·0%; risk difference 8·7%, 95% CI 4·5-12·9; RR 0·58, 0·47-0·73; p<0·0001). 10-year breast cancer mortality in this group was reduced by 4·2% (0·4-8·1; p=0·0034). No significant reduction in recurrence risk was found for sequential schedules of taxane plus anthracycline when compared with docetaxel plus cyclophosphamide (RR 0·94, 0·83-1·06; p=0·30). For the analysis of anthracycline regimens with versus without taxane, 35 trials (n=52 976) provided individual patient data. Larger recurrence reductions were seen from adding taxane to anthracycline regimens when the cumulative dose of anthracycline was the same in each group (RR 0·87, 0·82-0·93; p<0·0001; n=11 167) than in trials with two-fold higher cumulative doses of non-taxane (mostly anthracycline) in the control group than in the taxane group (RR 0·96, 0·90-1·03; p=0·27; n=14 620). Direct comparisons between anthracycline and taxane regimens showed that a higher cumulative dose and more dose-intense schedules were more efficacious. The proportional reductions in recurrence for taxane plus anthracycline were similar in oestrogen receptor-positive and oestrogen receptor-negative disease, and did not differ by age, nodal status, or tumour size or grade.

INTERPRETATION

Anthracycline plus taxane regimens are most efficacious at reducing breast cancer recurrence and death. Regimens with higher cumulative doses of anthracycline plus taxane provide the greatest benefits, challenging the current trend in clinical practice and guidelines towards non-anthracycline chemotherapy, particularly shorter regimens, such as four cycles of docetaxel-cyclophosphamide. By bringing together data from almost all relevant trials, this meta-analysis provides a reliable evidence base to inform individual treatment decisions, clinical guidelines, and the design of future clinical trials.

FUNDING

Cancer Research UK, UK Medical Research Council.

Model-Based Quantification of Impact of Genetic Polymorphisms and Co-Medications on Pharmacokinetics of Tamoxifen and Six Metabolites in Breast Cancer

Variations in clinical response to tamoxifen (TAM) may be related to polymorphic cytochromes P450 (CYPs) involved in forming its active metabolite endoxifen (ENDO). We developed a population pharmacokinetic (PopPK) model for tamoxifen and six metabolites to determine clinically relevant factors of ENDO exposure. Concentration-time data for TAM and 6 metabolites come from a prospective, multicenter, 3-year follow-up study of adjuvant TAM (20 mg/day) in patients with breast cancer, with plasma samples drawn every 6 months, and genotypes for 63 genetic polymorphisms (PHACS study, NCT01127295). Concentration data for TAM and 6 metabolites from 928 patients (n = 27,433 concentrations) were analyzed simultaneously with a 7-compartment PopPK model. CYP2D6 phenotype (poor metabolizer (PM), intermediate metabolizer (IM), normal metabolizer (NM), and ultra-rapid metabolizer (UM)), CYP3A4*22, CYP2C19*2, and CYP2B6*6 genotypes, concomitant CYP2D6 inhibitors, age, and body weight had a significant impact on TAM metabolism. Formation of ENDO from N-desmethyltamoxifen was decreased by 84% (relative standard error (RSE) = 14%) in PM patients and by 47% (RSE = 9%) in IM patients and increased in UM patients by 27% (RSE = 12%) compared with NM patients. Dose-adjustment simulations support an increase from 20 mg/day to 40 and 80 mg/day in IM patients and PM patients, respectively, to reach ENDO levels similar to those in NM patients. However, when considering Antiestrogenic Activity Score (AAS), a dose increase to 60 mg/day in PM patients seems sufficient. This PopPK model can be used as a tool to predict ENDO levels or AAS according to the patient's CYP2D6 phenotype for TAM dose adaptation.

Talazoparib versus chemotherapy in patients with germline BRCA1/2-mutated HER2-negative advanced breast cancer: final overall survival results from the EMBRACA trial

BACKGROUND

In EMBRACA, talazoparib prolonged progression-free survival versus chemotherapy (hazard ratio [HR] 0.542 [95% confidence interval (CI) 0.413-0.711]; P < 0.0001) and improved patient-reported outcomes (PRO) in germline BRCA1/2 (gBRCA1/2)-mutated advanced breast cancer (ABC). We report final overall survival (OS).

PATIENTS AND METHODS

This randomized phase III trial enrolled patients with gBRCA1/2-mutated HER2-negative ABC. Patients received talazoparib or physician's choice of chemotherapy. OS was analyzed using stratified HR and log-rank test and prespecified rank-preserving structural failure time model to account for subsequent treatments.

RESULTS

A total of 431 patients were entered in a randomized study (287 talazoparib/144 chemotherapy) with 412 patients treated (286 talazoparib/126 chemotherapy). By 30 September 2019, 216 deaths (75.3%) occurred for talazoparib and 108 (75.0%) chemotherapy; median follow-up was 44.9 and 36.8 months, respectively. HR for OS with talazoparib versus chemotherapy was 0.848 (95% CI 0.670-1.073; P = 0.17); median (95% CI) 19.3 months (16.6-22.5 months) versus 19.5 months (17.4-22.4 months). Kaplan-Meier survival percentages (95% CI) for talazoparib versus chemotherapy: month 12, 71% (66% to 76%)/74% (66% to 81%); month 24, 42% (36% to 47%)/38% (30% to 47%); month 36, 27% (22% to 33%)/21% (14% to 29%). Most patients received subsequent treatments: for talazoparib and chemotherapy, 46.3%/41.7% received platinum and 4.5%/32.6% received a poly(ADP-ribose) polymerase (PARP) inhibitor, respectively. Adjusting for subsequent PARP and/or platinum use, HR for OS was 0.756 (95% bootstrap CI 0.503-1.029). Grade 3-4 adverse events occurred in 69.6% (talazoparib) and 64.3% (chemotherapy) patients, consistent with previous reports. Extended follow-up showed significant overall improvement and delay in time to definitive clinically meaningful deterioration in global health status/quality of life and breast symptoms favoring talazoparib versus chemotherapy (P < 0.01 for all), consistent with initial analyses.

CONCLUSIONS

In gBRCA1/2-mutated HER2-negative ABC, talazoparib did not significantly improve OS over chemotherapy; subsequent treatments may have impacted analysis. Safety was consistent with previous observations. PRO continued to favor talazoparib.

Abstract CT072: Exploration of impact of tumor BRCA zygosity and genomic loss-of-heterozygosity (gLOH) on efficacy in Phase 3 EMBRACA study of talazoparib in patients (pts) with HER2-negative (HER2−) advanced breast cancer (ABC) and a germline BRCA1/2 (gBRCA1/2) mutation

Background: Loss-of-function mutations in genes encoding components of the homologous recombination machinery, notably BRCA1/2, are associated with tumor sensitivity to poly(ADP-ribose) polymerase (PARP) inhibitors. In EMBRACA, the PARP inhibitor talazoparib (TALA) demonstrated a significant improvement in the primary endpoint of progression-free survival (PFS) (HR [95% CI] 0.54 [0.41-0.71], P &lt; 0.001) vs physician's choice of chemotherapy (PCT) in pts with HER2− ABC and a gBRCA1/2 mutation.

Methods: Baseline tumor tissue (primary or metastatic sites) from 308 pts (71%) in the intent-to-treat population was sequenced using the FoundationOne CDx NGS panel. Mutations summarized below were known/likely pathogenic single-nucleotide variants, insertions, deletions, or rearrangements. Additional exploratory computational analyses pertinent to homologous recombination deficiency were performed, including somatic-germline-zygosity (SGZ) and gLOH assessments.

Results: 296/308 (96%) of evaluable pts exhibited ≥1 tumor BRCA mutation, with BRCA1 and BRCA2 mutations mainly mutually exclusive (4/308 [1%] pts had both BRCA1 and BRCA2 mutations). Of 12 pts with no apparent BRCA mutations, 7 exhibited tumor BRCA copy number alterations deemed pathogenic and 2 had BRCA single-nucleotide variants deemed of unknown pathogenicity. 195/236 (83%) BRCA-mutant (BRCAm) pts evaluable for BRCA LOH status were predicted to exhibit BRCA LOH by SGZ analysis. The potential impact of tumor BRCA mutational zygosity on PFS was explored in the TALA arm calculating HR by Cox proportional hazards model, comparing 122 pts with BRCA LOH with 27 pts without BRCA LOH. This analysis demonstrated no difference in PFS [HR (95% CI): 1.152 (0.680-1.951); P = 0.597)]. gLOH scores were variable, but mostly high: median (range), 21.8% (0.0, 52.7) and 20.5% (0.2, 40.5) for TALA and PCT arms, respectively. The potential association of gLOH scores with selected measures of efficacy was explored. Within both arms gLOH was similar in those pts achieving vs pts not achieving clinical benefit as defined by complete response, partial response, or stable disease ≥24 wks per RECIST v.1.1 as determined by investigator (P = 0.976 and 0.492, respectively, using 2-tailed t-test). In both arms, pts with gLOH ≥ median vs gLOH &lt; median exhibited similar PFS: HR (95% CI) 1.247 (0.828-1.879) for TALA; 1.238 (0.693-2.211) for PCT, with HR &lt;1 favoring gLOH ≥ median.

Conclusions: Selection based on gBRCA mutational status is appropriate to identify HER2− ABC pts with potential for clinical benefit with PARP inhibitors, with tumor BRCA zygosity and gLOH not impacting outcome (within the gBRCAm subset). Additional exploratory correlative analyses are ongoing and will be reported.

Citation Format: Jennifer K. Litton, A. Douglas Laird, Hope S. Rugo, Johannes Ettl, Sara A. Hurvitz, Miguel Martin, Henri Roché, Young-Hyuck Im, Annabel Goodwin, Joanne L. Blum, Wolfgang Eiermann, Ying Chen, Silvana Lanzalone, Jijumon Chelliserry, Akos Czibere, Lee A. Albacker, Garrett M. Frampton, Lida A. Mina. Exploration of impact of tumor BRCA zygosity and genomic loss-of-heterozygosity (gLOH) on efficacy in Phase 3 EMBRACA study of talazoparib in patients (pts) with HER2-negative (HER2−) advanced breast cancer (ABC) and a germline BRCA1/2 (gBRCA1/2) mutation [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr CT072.

Abstract P1-19-29: An integrated safety analysis of talazoparib monotherapy from five clinical trials (phase 1-3) in advanced cancers

Background: Talazoparib is a potent oral inhibitor of poly(ADP-ribose) polymerase (PARP) 1 and 2, which significantly improved progression-free survival versus standard-of-care chemotherapy in patients with HER2-negative advanced breast cancer (ABC; locally advanced/metastatic breast cancer) and a germline BRCA1/2 mutation (gBRCA1/2mut) in the Phase 3 EMBRACA trial (Litton J, et al. N Engl J Med. 2018;379:753-763). An integrated analysis of five clinical trials (Phase 1-3) in multiple tumor types was performed to evaluate the safety of talazoparib administered at 1 mg/day (d). Methods: Data were pooled from the ongoing Phase 3 randomized EMBRACA trial in HER2-negative gBRCA1/2mut ABC (NCT01945775), the Phase 2 non-randomized ABRAZO trial in gBRCA1/2mut ABC (NCT02034916), the Phase 1 trial in advanced/recurrent solid tumors (NCT01286987), the Phase 1 cardiac repolarization trial in advanced solid tumors (NCT03042910), and an ongoing open-label extension trial (NCT02921919). Results: 494 patients who received talazoparib 1 mg/d were included (Table). The most common all-grade adverse drug reactions (≥20%) with talazoparib were ANEMIA (includes preferred terms: anemia, decreased hemoglobin, decreased hematocrit; 49.6%), fatigue (47.6%), nausea (44.3%), NEUTROPENIA (neutropenia, decreased neutrophil count; 30.2%), THROMBOCYTOPENIA (thrombocytopenia, decreased platelet count; 29.6%), headache (26.5%), diarrhea (22.7%), alopecia (22.3%; Grade 1, 20.6%; Grade 2, 1.6%), vomiting (22.3%), and decreased appetite (20.2%). Grade 3/4 toxicities (≥10%) with talazoparib were ANEMIA (35.2%), NEUTROPENIA (17.4%), and THROMBOCYTOPENIA (16.8%). Overall 24 patients (4.9%) died within 30 days after the last dose of study drug; the most common cause of death was disease progression (13 patients; 2.6%). Other causes of death were reported in 1 patient each (cerebral hemorrhage, dyspnea, lung infection, lung metastases, respiratory failure, suspected veno-occlusive liver disease, and worsening of neurological symptoms); cause of death was not reported for 4 patients. The most common treatment-related serious adverse event was anemia (4.3%). Median duration of talazoparib exposure was 5.4 months (range, 0.0-61.1). Median relative dose intensity (defined as actual-dose intensity/planned-dose intensity) was 92.8%. Dosing interruptions due to TEAEs were reported for 48.6% of patients receiving talazoparib; median duration of dosing interruption due to TEAEs was 8.0 days (range, 1.0-121.0). Hematologic TEAEs (≥5%) associated with dose modification (interruption or reduction) included anemia (33.0%), neutropenia (15.8%), thrombocytopenia (13.4%), and decreased platelet count (5.9%); non-hematologic TEAEs (≥2%) associated with dose modification included fatigue (4.3%), vomiting (2.6%), and nausea (2.0%). Only 18 patients (3.6%) permanently discontinued due to a TEAE (anemia, 3 patients [0.6%]; other events, 1 patient each [0.2%]). Conclusions: Talazoparib monotherapy at 1 mg/d was generally well tolerated with few patients permanently discontinuing talazoparib due to AEs. Common toxicities were primarily hematologic and were manageable through dosing modifications and/or standard supportive care. Funding: Pfizer Inc.

Table Summary of TEAEsPhase 3 EMBRACA trialOpen-label trialsTalazoparibTalazoparib mg/dTalazoparib 1 mg/d1 mg/d populationbTalazoparibPCTABRAZONCT01286987NCT03042910OLEaTotalN=286N=126N=83N=77N=37N=46N=494Any TEAE282 (98.6)123 (97.6)81 (97.6)75 (97.4)28 (75.7)39 (84.8)484 (98.0)Grade 3 or 4 TEAE193 (67.5)80 (63.5)54 (65.1)52 (67.5)9 (24.3)21 (45.7)326 (66.0)Treatment-related Grade 3 or 4 TEAE159 (55.6)61 (48.4)48 (57.8)36 (46.8)3 (8.1)14 (30.4)260 (52.6)SAE91 (31.8)37 (29.4)23 (27.7)27 (35.1)3 (8.1)14 (30.4)156 (31.6)Treatment-related SAE26 (9.1)11 (8.7)11 (13.3)3 (3.9)1 (2.7)1 (2.2)42 (8.5)TEAE primary reason for permanent discontinuation13 (4.5)7 (5.6)3 (3.6)002 (4.3)18 (3.6)TEAE associated with dose modification190 (66.4)75 (59.5)55 (66.3)46 (59.7)4 (10.8)15 (32.6)308 (62.3)All data are number (%) of patients; d, day; OLE, open-label extension; PCT, physician’s choice of chemotherapy; SAE, serious adverse event; TEAE, treatment-emergent adverse event;aInitiated treatment with talazoparib; monotherapy (1 mg/d) in either the originating or the extension trial;b35 patients who initiated talazoparib 1 mg/d in two of the trials and continued in the OLE are counted only once in the total number of patients

Citation Format: Joannes Ettl, Jennifer Litton, Hope S. Rugo, Lida Mina, Miguel Martin, Nicholas Turner, Henri Roché, Zev Wainberg, Johann de Bono, Tiziana Usari, Mohamed Elmeliegy, Silvana Lanzalone, Akos Czibere, Liza DeAnnuntis, Sara A. Hurvitz. An integrated safety analysis of talazoparib monotherapy from five clinical trials (phase 1-3) in advanced cancers [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P1-19-29.

The importance of jointly analyzing treatment administration and toxicity associated with targeted therapies: a case study of regorafenib in soft tissue sarcoma patients

Background

Different methods have been proposed to analyze adverse events (AEs) associated with targeted therapies. While these AEs lead to dose adjustments for many patients, conventional reporting methods do not take drug administration into consideration. This paper underlines the importance of jointly reporting AEs and drug administration using prevalence, and proposes a complementary approach to reporting.

Patients and methods

The prevalence method estimates the probability of progression-free patients being in a particular health state (state 1: AEs with full dose; state 2: AEs with reduced dose; state 3: no AEs with reduced dose) at different time points. To take into account the impact of dose adjustments on efficacy, the weighted prevalence method can be used by assigning utility weights to the different health states. The benefit of these methods was illustrated using data from a phase II trial of regorafenib.

Results

Only 4.6% of progression-free patients developed mucositis/stomatitis (grade ≥2) at 3 months. The prevalence of patients not experiencing this AE but whose dose was reduced or treatment interrupted was 58.1%. The weighted prevalence of the regorafenib toxicity profile and dose reduction was higher in the control arm.

Conclusion

This case study confirms the importance of jointly analyzing AEs and drug administration. The weighted prevalence approach is an average score that incorporates the dimension of drug administration into AE assessment. This can be helpful for regulatory agencies as well as for clinicians to evaluate the benefit-risk ratio of therapies in their treatment choice.

Clinical trial

NCT01900743.

UCBG 2-04: Long-term results of the PACS 04 trial evaluating adjuvant epirubicin plus docetaxel in node-positive breast cancer and trastuzumab in the human epidermal growth factor receptor 2-positive subgroup

PURPOSE

We conducted a double-randomised phase III trial to evaluate a concomitant taxane-anthracycline regimen in node-positive breast cancer and the efficacy of trastuzumab in the human epidermal growth factor receptor 2 (HER2)-positive subpopulation.

METHODS

A total of 3010 patients with node-positive breast cancer were randomly assigned to receive 6 cycles of 500 mg/m² of fluorouracil, 100 mg/m² of epirubicin and 500 mg/m² of cyclophosphamide (FEC) or 75 mg/m² of epirubicin and 75 mg/m² of docetaxel (ED). Patients with HER2-positive tumours were secondary randomly assigned to either trastuzumab or observation. The primary end-point was disease-free survival (DFS) in the two chemotherapy arms.

RESULTS

After a 115-month median follow-up, DFS was not significantly better in the ED arm (DFS: 70%, 95% confidence interval [CI]: 67-72) than in the FEC arm (DFS: 68%, 95% CI: 65-70; hazard ratio [HR] = 0.88, 95% CI: 0.77-1.01; p = 0.064). The OS was not different between FEC (OS: 80%, 95% CI: 78-83) and ED (OS: 81%, 95% CI: 79-83); HR = 0.97, 95% CI: 0.81-1.16; p = 0.729). ED appeared more toxic. In the 528 HER2-positive subset, there was trend for a higher DFS, in the intention-to-treat population, in the trastuzumab arm (DFS: 68%, 95% CI: 61-74) than in the observation arm (DFS: 60%, 95% CI: 54-66; HR = 0.77, 95% CI: 0.57-1.03; p = 0.079). In the per-protocol population, DFS was significantly higher in the trastuzumab arm (DFS: 70%, 95% CI: 63-76) than in the observation arm (DFS: 59%, 95% CI: 53-65; HR = 0.69, 95% CI: 0.51-0.94; p = 0.0156). The OS was not different between these 2 arms.

CONCLUSION

This study did not show superiority of the concomitant anthracycline-taxane arm which was more toxic in high-risk node-positive breast cancer patients. Long-term results of the HER2-positive subpopulation are in line with those of the other adjuvant trastuzumab trials but quantitatively less pronounced mostly because of lack of power.

Factors Affecting Tamoxifen Metabolism in Patients With Breast Cancer: Preliminary Results of the French PHACS Study

In addition to the effect of cytochrome P450 (CYP) 2D6 genetic polymorphisms, the metabolism of tamoxifen may be impacted by other factors with possible consequences on therapeutic outcome (efficacy and toxicity). This analysis focused on the pharmacokinetic (PK)-pharmacogenetic evaluation of tamoxifen in 730 patients with adjuvant breast cancer included in a prospective multicenter study. Plasma concentrations of tamoxifen and six major metabolites, the genotype for 63 single-nucleotide polymorphisms, and comedications were obtained 6 months after treatment initiation. Plasma concentrations of endoxifen were significantly associated with CYP2D6 diplotype (P < 0.0001), CYP3A4*22 genotype (P = 0.0003), and concomitant intake of potent CYP2D6 inhibitors (P < 0.001). Comparison of endoxifen levels showed that the CYP2D6 phenotype classification could be improved by grouping intermediate metabolizer (IM)/IM and IM/poor metabolizer diplotype into IM phenotype for future use in tamoxifen therapy optimization. Finally, the multivariable regression analysis showed that formation of tamoxifen metabolites was independently impacted by CYP2D6 diplotype and CYP3A4*22, CYP2C19*2, and CYP2B6*6 genetic polymorphisms.

Biosimilar filgrastim treatment patterns and prevention of febrile neutropenia: a prospective multicentre study in France in patients with solid tumours (the ZOHé study)

Background

The ZOHé study was a prospective, non-interventional, multicentre study in France to assess the use of biosimilar filgrastim Zarzio® (Sandoz filgrastim) in routine clinical practice in patients at risk of neutropenia-inducing chemotherapy (CT).

Methods

Patients ≥ 18 years undergoing CT for a malignant disease and with a first prescription for Zarzio® were enrolled in two cohorts according to tumour type: solid tumour or haematological malignancy; results from the solid tumour cohort are reported here. Analyses primarily described the prescription and use of Zarzio® in current practice, and also included identification of factors linked to prescription for primary prophylaxis and comparison of Zarzio® use in relation to European Organisation for Research and Treatment of Cancer (EORTC) guidelines.

Results

Responses were obtained from 125 physicians and 1179 patients with solid tumours, allowing robust statistical analysis of the data. Use of Zarzio® in clinical practice was relatively standardised and followed label indication. The patient profile was in line with EORTC guidelines for granulocyte colony-stimulating factor (G-CSF) febrile neutropenia (FN) prophylaxis, and the majority of patients had ≥ 1 EORTC factor(s) for increased risk of febrile neutropenia. Some patients (10.8%) received Zarzio® despite receiving CT regimens categorised in guidelines as low (< 10%) FN risk (‘over prophylaxis’). Nearly half of patients’ CT regimens did not have a recommended FN risk category. Zarzio® was commonly initiated as primary prophylaxis; initiation in Cycle ≥ 2 of the current line of CT was associated more with a history of neutropenia. The safety profile of Zarzio® was confirmed.

Conclusions

Use of Zarzio® in routine clinical practice is generally in line with EORTC guidelines for prophylaxis of CT-induced neutropenia. Patient-related risk factors appear to be a stronger driver of clinicians’ decision to initiate Zarzio® than CT risk category for FN. The intrinsic risk of FN associated with a specific CT protocol is often miscategorised by physicians. In contrast to earlier reports of underuse of G-CSF prophylaxis, over prophylaxis is observed in a small subgroup of patients with FN risk of < 10%.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4986-1) contains supplementary material, which is available to authorized users.

UCBG 2-08: 5-year efficacy results from the UNICANCER-PACS08 randomised phase III trial of adjuvant treatment with FEC100 and then either docetaxel or ixabepilone in patients with early-stage, poor prognosis breast cancer

PURPOSE

UNICANCER-PACS08 compared adjuvant FEC (5-FU; epirubicin; cyclophosphamide) then docetaxel to FEC then ixabepilone in poor prognosis early breast cancer (BC). We evaluated whether replacing docetaxel with ixabepilone would increase 5-year disease-free survival (DFS).

PATIENTS AND METHODS

Triple-negative breast cancer (TNBC) or oestrogen receptor (ER)+/progesterone receptor (PR)-/HER2- BC patients were randomised to receive standard FEC (3 cycles) followed by 3 cycles of either docetaxel (100 mg/m²) or ixabepilone (40 mg/m²). Radiotherapy was mandatory after conservative surgery; ER+ patients received endocrine therapy.

RESULTS

Seven hundred sixty-two patients were enrolled between October 2007 and September 2010. Baseline characteristics were balanced between arms. Median follow-up was 66.7 months. Median DFS was not reached; 5-year DFS rate was 76% with docetaxel and 79% with ixabepilone (hazard ratio [HR] = 0.80; 95% confidence interval [CI] = 0.58-1.10; p = 0.175). Median overall survival (OS) was not reached; 5-year OS rate was 86% versus 84% (HR = 0.97; 95% CI = 0.66-1.42; p = 0.897). TNBC patients treated with ixabepilone had a 23% lower risk of relapse compared to docetaxel (HR for DFS = 0.77; 95% CI = 0.53-1.11; p = 0.168). DFS was longer with ixabepilone than docetaxel in patients with grade II-III lymphocytic infiltration (HR = 0.55; 95% CI = 0.29-1.05; p = 0.063). All patients experienced ≥1 adverse events (AEs): 75% reported grade III-IV AEs and two (<1%) had grade V AEs (both with neutropenia and infection receiving ixabepilone).

CONCLUSION

After adjuvant FEC, ixabepilone was comparable to docetaxel for treating poor prognosis early BC patients. The benefit of ixabepilone in subgroups (patients with TNBC and grade II-III lymphocytic infiltration) requires further evaluation.

Talazoparib in Patients with Advanced Breast Cancer and a Germline BRCA Mutation

BACKGROUND

The poly(adenosine diphosphate-ribose) inhibitor talazoparib has shown antitumor activity in patients with advanced breast cancer and germline mutations in BRCA1 and BRCA2 ( BRCA1/2).

METHODS

We conducted a randomized, open-label, phase 3 trial in which patients with advanced breast cancer and a germline BRCA1/2 mutation were assigned, in a 2:1 ratio, to receive talazoparib (1 mg once daily) or standard single-agent therapy of the physician's choice (capecitabine, eribulin, gemcitabine, or vinorelbine in continuous 21-day cycles). The primary end point was progression-free survival, which was assessed by blinded independent central review.

RESULTS

Of the 431 patients who underwent randomization, 287 were assigned to receive talazoparib and 144 were assigned to receive standard therapy. Median progression-free survival was significantly longer in the talazoparib group than in the standard-therapy group (8.6 months vs. 5.6 months; hazard ratio for disease progression or death, 0.54; 95% confidence interval [CI], 0.41 to 0.71; P<0.001). The interim median hazard ratio for death was 0.76 (95% CI, 0.55 to 1.06; P=0.11 [57% of projected events]). The objective response rate was higher in the talazoparib group than in the standard-therapy group (62.6% vs. 27.2%; odds ratio, 5.0; 95% CI, 2.9 to 8.8; P<0.001). Hematologic grade 3-4 adverse events (primarily anemia) occurred in 55% of the patients who received talazoparib and in 38% of the patients who received standard therapy; nonhematologic grade 3 adverse events occurred in 32% and 38% of the patients, respectively. Patient-reported outcomes favored talazoparib; significant overall improvements and significant delays in the time to clinically meaningful deterioration according to both the global health status-quality-of-life and breast symptoms scales were observed.

CONCLUSIONS

Among patients with advanced breast cancer and a germline BRCA1/2 mutation, single-agent talazoparib provided a significant benefit over standard chemotherapy with respect to progression-free survival. Patient-reported outcomes were superior with talazoparib. (Funded by Medivation [Pfizer]; EMBRACA ClinicalTrials.gov number, NCT01945775 .).

The 21-gene Recurrence Score® assay predicts distant recurrence in lymph node-positive, hormone receptor-positive, breast cancer patients treated with adjuvant sequential epirubicin- and docetaxel-based or epirubicin-based chemotherapy (PACS-01 trial)

Background

The 21-gene Recurrence Score (RS) result predicts outcome and chemotherapy benefit in node-negative and node-positive (N+), estrogen receptor-positive (ER+) patients treated with endocrine therapy. The purpose of this study was to evaluate the prognostic impact of RS results in N+, hormone receptor-positive (HR+) patients treated with adjuvant chemotherapy (6 cycles of FEC100 vs. 3 cycles of FEC100 followed by 3 cycles of docetaxel 100 mg/m²) plus endocrine therapy (ET) in the PACS-01 trial (J Clin Oncol 2006;24:5664-5671).

Methods

The current study included 530 HR+/N+ patients from the PACS-01 parent trial for whom specimens were available. The primary objective was to evaluate the relationship between the RS result and distant recurrence (DR).

Results

There were 209 (39.4%) patients with low RS (< 18), 159 (30%) with intermediate RS (18-30) and 162 (30.6%) with high RS (≥ 31). The continuous RS result was associated with DR (hazard ratio = 4.14; 95% confidence interval: 2.67-6.43; p <  0.001), adjusting for treatment. In multivariable analysis, the RS result remained a significant predictor of DR (p <  0.001) after adjustment for number of positive nodes, tumor size, tumor grade, Ki-67 (immunohistochemical status), and chemotherapy regimen. There was no statistically significant interaction between RS result and treatment in predicting DR (p = 0.79).

Conclusions

After adjustment for clinical covariates, the 21-gene RS result is a significant prognostic factor in N+/HR+ patients receiving adjuvant chemoendocrine therapy.

Trial registration

Not applicable.

Evaluation of the Theoretical Teaching of Postgraduate Radiation Oncology Medical Residents in France: a Cross-Sectional Study

This study's purpose was to have residents evaluate Radiation Oncology (RO) theoretical teaching practices in France. An anonymous electronically cross-functional survey on theoretical teaching practices in the RO residents was conducted by (i) collecting data from residents in the medical faculties in France, (ii) comparing the data across practices when possible and (iii) suggesting means of improvement. A total of 103 out of 140 RO residents responded to the survey (73.5% response rate). National, inter-university, university and internships courses do not exist in 0% (0), 16.5% (17), 53.4% (55) and 40.8% (42) of residents, respectively. Residents need additional training due to the shortage of specialised postgraduate degree training (49.5% (51)), CV enhancement to obtain a post-internship position (49.5% (51)) or as part of a career plan (47.6% (49)). The topics covered in teaching to be improved were the following: basic concept 61.2% (63), advanced concept 61.2 (63) and discussion of frequent clinical cases 50.5% (52). The topics not covered in teaching to be improved were the following: the development of career (66.0% (68)), medical English (56.3% (58)), the organisation of RO speciality (49.5% (51)) and the hospital management of RO department (38.8% (40)). This is the first national assessment of theoretical teaching of RO residents in France.

Abstract P3-12-03: Impact of genetic polymorphisms on plasma levels of tamoxifen and its metabolites and toxicity: 6-months results of the adjuvant breast cancer longitudinal PHACS study (NCT01127295)

Supported by a PHRC grant (#09-18-005)

Background: The role of CYP2D6 genetic polymorphisms and plasma levels of active metabolites of tamoxifen (TAM) on clinical response and occurrence of side effects remains controversial. We conducted a prospective, adjuvant, multicentre, 3-year follow-up study of breast cancer patients in order to evaluate the relationships between pharmacogenetics, pharmacokinetics and toxicity of TAM and its metabolites (n=879) or aromatase inhibitors (AI, n=1098). The present report focuses on the evaluation at 6 months after inclusion of 864 patients treated with 20 mg/day TAM.The clinical results and the AI PG/PK analyses are described elsewhere (abstracts #851544 and #851525).

Methods: Residual plasma concentrations for tamoxifen and its 6 major metabolites (endoxifen ENDO, 4-hydroxy-tamoxifen 4-OH-TAM, N-desmethyl TAM, TAM-N-oxyde, 4'-OH-TAM and Z'ENDO) at 6 months after start of treatment were measured by UPLC-MS/MS in 789 patients. Nine patients with TAM concentrations below the limit of quantification were excluded for non-compliance. SNP genotyping of 95 selected SNPs was performed on the Biomark (Fluidigm) in a microfluidic multiplex 96 dynamic array chip with Taqman assays and was available for 857 patients. Patients were classified according to their CYP2D6 metaboliser status (MS) (PM, IM, EM and UM) based on presence of functional, decreased function or no functional alleles (*4, *6, *7, *9, *10, *17, *41) and number of CYP2D6 copies (*5 or duplication). Metabolic ratios (MR) were calculated for TAM/4-OH-TAM, TAM/N-desmethyl tamoxifen (NDT), NDT/ENDO and 4-OH-TAM/ENDO. Anti-estrogenic activity score (AAS) was calculated according to a recently proposed algorithm (De Vries Schultink et al.,Breast Cancer Res Treat. 2017).Toxicity was measured as a binary outcome (first occurrence or worsening of hot flushes, fatigue, depression, pain, arthralgia, vaginal dryness). All genetic associations were adjusted for multiple testing.

Results: ENDO concentration and AAS increased significantly with CYP2D6 MS (p&lt;0.001). The presence of a CYP3A4*22 allele was significantly associated with endoxifen concentrations; this association remained significant after adjusting for CYP2D6 MS. TAM/4-OH-TAM MR was significantly influenced by the presence of CYP3A4*22, CYP2C19*2 and *17, and CYP2D6 status. The percentage of patients having an AAS&gt;=1798 (i.e., threshold previously associated with recurrence-free survival RFS by De Vries et al. 2017) was 6%, 50%, 84% and 91% of patients respectively classified as PM, IM, EM and UM. Side effects were not significantly associated with higher levels of TAM metabolites concentrations. After correction for multiple testing, SNPs or CYP2D6 MS were not significantly associated with occurrence or worsening of adverse events, premature treatment discontinuations or switch due to toxicity within the first 6 months.

Conclusions: In this large prospective study, we quantified the impact of PG on TAM PK and AAS, previously shown to predict RFS. Although the toxicity observed after 6 months of TAM does not seem correlated with PK or PG, these relationships need to be re-evaluated during the 3-year follow-up.

Citation Format: White-Koning M, Arellano C, Le Morvan V, Evrard A, Puzskiel A, Vachoux C, Dauba J, Houyau P, Poublanc M, Robert J, Boyer J-C, Roché H, Thomas F, Chatelut E. Impact of genetic polymorphisms on plasma levels of tamoxifen and its metabolites and toxicity: 6-months results of the adjuvant breast cancer longitudinal PHACS study (NCT01127295) [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-12-03.

Abstract P1-07-07: Overtime distribution and predictors of local recurrences (LRs) in patients with hormone receptor positive (HR+) and node positive (N+) breast cancers (BCs): 10 -year follow-up analysis of UNICANCER-PACS 01 and PACS04 trials

Purpose:Incidence of LRs in patients (pts) treated for HR+ HER2- localized BC and distribution overtime have not been described in recent years after introduction of new generation of adjuvant therapies and more extensive use of radiotherapy. We evaluated the incidence and distribution overtime of LRs in pts with HR+ HER2- N+ BCs who entered PACS 01 and PACS04 trials.

Patients and Methods: Data were analyzed from 2909 pts with HR+/HER2- BC out of 5008 included in both trials. Pts underwent mastectomy or lumpectomy plus axillary dissection for a localized N+ BC and, according to study design, were randomized to: 6 cycles of FE100C (standard arm) versus FE100C x 3 cycles followed by docetaxel 100 mg/m2 x 3 cycles (FEC-D) (PACS01) or 6 cycles of Epirubicin 75mg/m2 and Docetaxel 75 mg/m2 (ED75)(PACS04). Loco-regional radiotherapy was mandatory after lumpectomy and recommended in other cases. All pts received 5 years of hormone therapy (HT). A competing risk multivariate analysis was conduct using Fine and Gray model to identify risk factors associated to isolated LRs. Competing events were nodal recurrence, contralateral BC, distant metastasis and death. Cumulative incidence associated to each event was estimated by a Kablfleish-Prentice estimator.

Results: Pts' median age was 50 (22-65); 67.2% underwent lumpectomy, 32.8% mastectomy; 67.6% had 1 to 3 N+, 32.4% more than 3 N+; 45.7% had lymphovascular invasion; 49.5% received FE100C, 35.8% ET75, 14.7% had FEC-D; while radiotherapy was given to 97.3% and HT to 92.2%, of whom 90.5% received tamoxifen. At a median follow-up of 9.1 years, 60 pts (2.1%) experienced LR as first event. The 5-year and 10-year cumulative incidence of LRs were 1.04% and 2.53%, respectively. The cumulative incidence of LRs increased from the 5th year, and the annual risk tended to remain constant over time. Multivariate analysis of competing risk showed that younger age, conservative surgery and omission of HT (not prescribed or non-adherence) were independently associated with risk of developing LRs.

Table 1. Multivariate analysis on competing risk of predictors of LRsVariablesHR 95%CIP valueAge at entry (&lt;35 years, ≥ 35)*0.95 [0.92; 0.99]0.009Mastectomy, lumpectomy0.39 [0.17; 0.86]0.020&gt; 20mm, ≤20 mm0.68 [0.37; 1.24]0.203N+ &gt;3, 1-31.73 [0.99; 3.02]0.055Grade II/III, I1.06 [0.50; 2.24]0.885PR+,PR-1.78 [0.70; 4.53]0.223Type of chemotherapy 3FEC-3D, 6FEC/6ET1.32 [0.65; 2.69]0.446Number of cycles 6, &lt;60.71 [0.17; 0.75]0.630Hormone therapy Yes,No0.36 [0.17; 0.75]0.006*treated as continuous variable

Conclusion: Our analysis showed that incidence of LRs in pts with HR+ N+ BCs treated within PACS trials were considerably lower as compared to earlier studies. These findings may reflect differences in treatment era, as the more extensive use of radiotherapy and new generation of adjuvant chemotherapy. Despite current adjuvant strategies, young age at diagnosis and omission of HT remain independent risk factors of LRs.

Citation Format: Pistilli B, Filleron T, Mazouni C, Zingarello A, Lacroix-Triki M, Rivera S, Coudert B, Serin D, Canon J-L, Campone M, Bachelot T, Goncalves A, Levy C, Cottu P, Petit T, Eymard J-C, Tunon De Lara C, Roché H, Roca L, Lemonnier J, Delaloge S. Overtime distribution and predictors of local recurrences (LRs) in patients with hormone receptor positive (HR+) and node positive (N+) breast cancers (BCs): 10 -year follow-up analysis of UNICANCER-PACS 01 and PACS04 trials [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P1-07-07.

Abstract P3-12-10: First 6-month report of the longitudinal PHACS study (Pharmacology and Hormonotherapy (HT) for Adjuvant breast Cancer (BC) Study, NCT01127295)

Background: BC is a hormone-dependent disease for 75% of pts. HT is used in both adjuvant and metastatic settings for hormone–receptor (HR) positive tumors. In adjuvant situation, a 5-year HT period at least is recommended. Side-effects (SE) frequently alter quality of life and compliance, reducing the well-known benefits in risks of relapses and specific deaths. Underlying mechanisms are well understood for estrogen deprivation-induced events such as hot flashes, but little is known on arthralgia under aromatase inhibitors (AI). So, pharmacogenomics (PG), pharmacokinetics (PK), potential medications interactions are of value to explain individual drugs exposures, possible related side-effects and compliance to treatment.

Methods: We performed a prospective, multicenter, longitudinal study registering early clinical outcomes and SE during the first 3 years of adjuvant HT with tamoxifen (T) or AI. All tumors expressed at least one HR (&gt;10%). The choice of HT molecule and one-drug or sequential treatment were left to the investigator. Pts were followed every 6 months with clinical examination by the referent oncologist and PK sampling each time. Biologic research consisted in PG investigations of different genes involved in the PK and pharmacodynamics of T and AI (95 SNPs) at baseline. SE, concurrent medications and compliance were registered by both the pts on a diary card and the physician. Evaluation was done only on new occurrence or increased grade of symptoms.

Results: This first report focuses on characteristics of the population and the results after the 6 first months of treatment. Between June 2010 and October 2014, 23 centers recruited 2000 pts. 23 were excluded leaving 1977 fully evaluable women; 879 (44%) started with T, 1098 (55%) with AI (554 letrozole (L), 390 anastrozole (A), 154 exemestane (E)). 56% of them had previously received chemotherapy, 96% radiotherapy and 8% trastuzumab.

Main characteristics were well balanced between the 2 classes of drugs; T was given mainly for pre- or perimenopausal pts. Most frequent co-morbidities were hypertension (8% T, 31% AI) and dyslipidemia or diabetes (T 11%, AI 26%). To note, almost 30% of pts described arthralgias at entrance and 37% had hot flashes.

At 6 months, 122 pts (6%; 43 T, 79 AI) had stopped treatment mainly for toxicity (11 T; 12 AI), progression or death (7 T; 4 IA), personal reasons (15 T; 37AI); 4 asked for changing T and 52 AI (equally for the 3 drugs). All these events were significantly more frequent for AI pts (p=0.042) and with E within the AI class (p&lt;0.001).

Main changes in onset or increased intensity of symptoms concerned hot flushes with all drugs (30%), asthenia (20%), insomnia (20%), weight gain (17%), arthralgias (15% for T, 30% for AI), thrombotic events (24 of which 11 with T). 3 grade3 SAE HT-related were reported.

Biological data are reported in 2 other abst. (M. White-Koning. abst.#850248, F. Thomas, abst.#851525).

Conclusions: These preliminary data on the first 6-months exposure to HT on adjuvant setting in the real-life confirm early rates of withdraws and toxicities. Longer follow-up and subsequent PK analysis should help to understand persistent side-effects and reasons for non-compliance to adjuvant HT.

Citation Format: Roché H, Venat-Bouvet L, Debled M, Jacot W, Suc E, Dalenc F, Molnar-Stanciu D, Dohollou N, Franck D, Ferrer C, Laharie-Mineur H, Lavau-Denes S, Massabeau C, Mauries V, Robert J, Pinguet F, Marquet P, Evrard A, Chatelut E, Filleron T. First 6-month report of the longitudinal PHACS study (Pharmacology and Hormonotherapy (HT) for Adjuvant breast Cancer (BC) Study, NCT01127295) [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-12-10.

Abstract PD7-06: MAAT: Menses after adjuvant treatment. Prediction of menses recovery after chemotherapy for early breast cancer (BC) by using a nomogram model in UNICANCER PACS04 and PACS05 trials

Purpose:The likelihood of menses recovery (MR) is largely variable in premenopausal patients (pts) receiving adjuvant chemotherapy for BC. Quantifying this probability for each single patient could impact discussion of chemotherapy side effects and better individualize fertility counseling.We performed a pooled analysis from PACS04 and PACS05 randomized trials aiming to develop a nomogram to estimate the probability of menses recovery at 6 and 18 months (mos) after the end of adjuvant chemotherapy (CT) for premenopausal pts with early BC.

Patients and Methods: The analyzed population consisted of 1683 pts who were premenopausal and ≤ 50 (out of 4524 enrolled in both trials). In PACS05 node-negative BC pts were randomized to 4 or 6 cycles of FE100C (standard arm); in PACS04 node-positive pts were randomized to 6 cycles of FE100C or 6 cycles of Epirubicin 75mg/m2 and Docetaxel 75 mg/m2 (ED75). Endocrine therapy (ET) (Tamoxifen) x 5 years was mandatory for ER+ BC. Variables significantly associated with MR in the univariate analysis (P&lt;0.20) were included in the multivariate analysis. Using this data set, a logistic regression-based nomogram was developed to predict MR at 6 and 18 mos.

Results: Pts' characteristics were: median age 43 (22-50), median body mass index (BMI) at baseline 22.6 (15.6-54.7), at the end of chemotherapy 22.8 (15.8-58.6). ED75 was administrated to 517 (30.7%), while 802 (47.7%) received 6FE100C, 364 (21.6) 4FE100C. Trastuzumab was given to 122 (7.2%), ET to 1229 (73%) pts. CT-induced amenorrhea was observed in 1407 (83.6%) pts. Factors associated to MR were assessed on 1210 pts (excluding pts who recovered menses during CT or of whom date of recovery was not specified). At a median follow-up of 90 mos, 28.2% (342/1210) of pts had recovered menstrual cycles: 11% (133/1210) at 6 mos and 24.3% (294/1210) at 18 mos. Multivariate analysis showed that younger age, higher BMI at the end of CT, non-alkylating agents and absence of ET were independently associated to MR.

Table 1 Multivariate Cox regression analysis of menses recoveryVariablesHR (95%CI)P valueAge1.49 (1.16-1.93)&lt; 0.002Age2*0.99 [0.98-0.99]&lt;0.0001BMI after CT1.02 (0.99-1.04)0.07Alkylating agents0.72 (0.57-0.90)0.004Endocrine Therapy0.50 (0.40-0.62)&lt;0.001* The quadratic term in the age variable accounts for the non-linearity of the relation between the age and the probability of recovering menses. Overall this probability tend to decrease when age increase with a greater decrease for the older patients.

Nomogram concordance-index was 0.749 and 0.750 for predicting MR at 6 and 18 mos respectively. A better calibration was observed at 18 mos, comparing nomogram predictions with the actual probability of MR in the 1210 women.

Conclusion:Our analysis confirmed the possibility of developing a user-friendly nomogram for predicting menses recovery after adjuvant chemotherapy. As next step, we will externally validate our nomogram on CANTO premenopausal population, one of the biggest national cohorts aiming to assess the long-term impact of cancer treatments toxicities (UNICANCER NCT01993498 - http://etudecanto.org/).

Citation Format: Pistilli B, Mazouni C, Zingarello A, Faron M, Saghatchian M, Grynberg M, Spielmann M, Kerbrat P, Roché H, Lorgis V, Bachelot T, Campone M, Levy C, Goncalves A, Lesur A, Veyrat C, Vanlemmens L, Lemonnier J, Delaloge S. MAAT: Menses after adjuvant treatment. Prediction of menses recovery after chemotherapy for early breast cancer (BC) by using a nomogram model in UNICANCER PACS04 and PACS05 trials [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr PD7-06.

Abstract P3-12-07: Pharmacogenetic determinants of aromatase inhibitors pharmacokinetics and side effects: 6-month results of the adjuvant breast cancer longitudinal PHACS study (NCT01127295)

Supported by a PHRC grant (#09-18-005)

Background: Recent literature has suggested that germline genetic variants of drug-metabolizing enzymes or CYP19A1 (coding for aromatase) may be involved in the systemic aromatase inhibitors (AI) concentrations or the occurrence of side effects (Hertz et al. Pharmacogenomics 2017). A prospective multicentre 3-year follow-up study was carried out to investigate the relationships between pharmacogenetics (PG), pharmacokinetics (PK) and toxicity in breast cancer patients treated with adjuvant AI (n=1098) or tamoxifen (n=879). The clinical results and the tamoxifen PG/PK analyses are described elsewhere (abstracts #851544 and #850248).

Methods: SNP genotyping of 95 SNPs was performed on the Biomark (Fluidigm) with Taqman assays and was available for 373, 515 and 151 patients treated with anastrozole (ANA), letrozole (LETRO) and exemestane (EXE) respectively. CYP2A6 metaboliser status (MS) (poor, intermediate or normal) was determined based on alleles function (*1, *9, *2) and number of CYP2A6 copies. Trough plasma concentrations of each drug were determined 6 months after the start of the study by UPLC-MS/MS and were available for 342, 463 and 130 patients of the ANA, LETRO and EXE arms. Patients with AI concentrations below the limit of quantification were excluded for non-compliance (9 patients for ANA, 8 patients for LETRO and 7 patients for EXE). Toxicity was measured as a binary outcome (occurrence or worsening of hot flushes, fatigue, pain, arthralgia, vaginal dryness). All genetic associations were adjusted for multiple testing.

Results: ANA concentration was significantly higher in patients experiencing pain (p=0.025) and was associated with rs28365063 (UGT2B7 g.372A&gt;G).

LETRO concentrations were strongly associated with CYP2A6 metabolizer status (p=0.0001) but did not differ in patients with or without toxicity.

In the EXE arm, patients with hot flushes or arthralgia had a significantly lower level of exemestane (p= 0.0002 and p=0.023 respectively) but since the metabolism of EXE leads to active 17-hydroexemestane, we can hypothesize that the lower EXE concentration is an indirect reflection of the metabolite formation. A SNP (rs2307424) in NR1I3 gene (coding for the constitutive androstane receptor CAR) was associated with EXE concentrations. CAR has been shown to regulate CYP2B6, which is involved in the formation of 6-hydroxy-methyl-exemestane (inactive metabolite).

Regarding the relationships between PG and toxicity, in the ANA arm, 3 SNPs of CYP19A1 gene tended to be associated with hot flushes worsening (rs934635) and arthralgia (rs10046 and rs2304463) but did not remain significant after multiple tests correction. In the EXE arm, several SNPs in NR1I3 gene were associated with fatigue.

In the LETRO arm, patients with a poor CYP2A6 MS had a higher risk of experiencing depression.

Conclusions: Our study confirms the predominant role of CYP2A6 in LETRO PK. To our knowledge, this is the first study to report on the role of UGT2B7 rs28365063 in ANA and NR1I3 in EXE PK and side effects. These relationships need to be re-evaluated with the drug concentrations obtained during the 3-year follow-up.

Citation Format: Thomas F, Marquet P, Pinguet F, White-Koning M, Robert J, Tafzi N, Solassol I, Despax R, Levasseur N, Ellis S, Massoubre A, Mbatchi L, Le Morvan V, Roché H, Chatelut E, Evrard A. Pharmacogenetic determinants of aromatase inhibitors pharmacokinetics and side effects: 6-month results of the adjuvant breast cancer longitudinal PHACS study (NCT01127295) [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-12-07.

Abstract P2-02-05: Persistence of PIK3CA mutations detection in cell free tumor DNA as surrogate markers for hormonosensibility in patients with hormone receptor-positive breast cancer. The miRho clinical study

Background: HT resistance occurs in nearly all patients with mBC. The identification of early predictive biomarkers of HT failure could help tailoring monitoring or an early change in HT. Circulating biomarkers would allow, a global evaluation of all the metastatic sites without the need of invasive biopsies. Mutation in the phosphatidylinositol 3 phosphate kinase gene (PIK3CA) is one of the most frequent events in ER+ BC and has been involved in HT resistance. We evaluated the early predictive value of cell free DNA (cfDNA) PIK3CA detection in a population of first line HT BC patients.

Material and methods: 39 patients treated for an ER+/HER2- metastatic BC by first line HT in 2 French Comprehensive Cancer Centers were prospectively included in a dedicated clinical trial (NCT01612871) between June 2012 and January 2014. Serial blood sampling was performed before the initiation of HT (T0), 4 weeks (T1), 3 months (T3), 6 months (T6) and at tumor progression. Patients were followed until progression or end of the study (2 years follow-up). cfDNA was isolated from plasma using the QiaAmp circulating nucleic acid isolation kit (Qiagen). Mutation detection was performed using droplet digital PCR on a QX100TM system (Bio-Rad). The assay targeted wild type PIK3CA and mutations p.E542K, p.E545K in exon 9 and p.H1047R in exon 20. Target concentration was calculated as copies/reaction and cfDNA concentrations were reported as number of copies/mL of plasma. To assess the limit of detection of the three assays, isogenic reference DNA with known mutant allele frequency was used (Horizon Diagnostics). Based on confidence interval for Poisson parameter, a sample was considered positive if the average mutant copies detected was 4 copies and above per reaction.

Results: Median age of the population was 63 (range 40-86). HT was as follow: letrozole 32, tamoxifen 5, anastrozole 1 and exemestane 1 patients, respectively. Most patients (28, 71.8%) presented with non-measurable disease, precluding a relevant evaluation of predictive factors for response. Progression-free survival (PFS) was used instead as primary endpoint. Serum samples results were available for 37 and 35 patients at T0 and T1 respectively. PIK3CA mutations were present in 10 (27.8%) and 5 (14.3%) cases at T0 and T1 respectively. While presence of a cfDNA PIK3CA mutation in the T0 sample was not associated with PFS, the persistence of a detectable circulating mutation at T1 was highly significant of a worse PFS (40% vs. 76.7% at 1 year; p=0.0053).

Conclusions: In this dedicated clinical trial, 4-weeks persistence of cfDNA PIK3CA mutation appears highly correlated with PFS. Early identification of this mutated population could allow the evaluation of therapies targeting the PI3K/AKT/mTOR pathway in a selected population affected with an unfavorable prognosis. Dedicated studies and ancillary studies of such targeted therapies are warranted.

Citation Format: Jacot W, Dalenc F, Lopez-Crapez E, Chaltiel L, Durigova A, Gros N, Lacaze J-L, Pouderoux S, Gladieff L, Romieu G, Roché H, Filleron T, Lamy P-J. Persistence of PIK3CA mutations detection in cell free tumor DNA as surrogate markers for hormonosensibility in patients with hormone receptor-positive breast cancer. The miRho clinical study [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P2-02-05.

Choosing a career in oncology: results of a nationwide cross-sectional study

BACKGROUND

Little information is currently available concerning young medical students desire to pursue a career in oncology, or their career expectations.

METHODS

This project is a cross-sectional epidemiological study. A voluntary and anonymous questionnaire was distributed to all young oncologists studying in France between the 2nd of October 2013 and the 23rd of February 2014.

RESULTS

The overall response rate was 75.6%. A total of 505 young oncologists completed the questionnaire. The main determining factors in the decision to practice oncology were the cross-sectional nature of the field (70.8%), the depth and variety of human relations (56.3%) and the multi-disciplinary field of work (50.2%). Most residents would like to complete a rotation outside of their assigned region (59.2%) or abroad (70.2%) in order to acquire additional expertise (67.7%). In addition, most interns would like to undertake a fellowship involving care, teaching and research in order to hone their skills (85.7%) and forge a career in public hospitals (46.4%). Career prospects mainly involve salaried positions in public hospitals. Many young oncologists are concerned about their professional future, due to the shortage of openings (40.8%), the workload (52.8%) and the lack of work-life balance (33.4%).

CONCLUSIONS

This investigation provides a comprehensive profile of the reasons young oncologists chose to pursue a career in oncology, and their career prospects.

Safety Results and Analysis of Eribulin Efficacy according to Previous Microtubules-Inhibitors Sensitivity in the French Prospective Expanded Access Program for Heavily Pre-treated Metastatic Breast Cancer

Purpose

Eribulin is approved for advanced breast cancers refractory to anthracyclines and taxanes. Efficacy according to sensitivity to previous therapies has been poorly explored.

Materials and Methods

Safety data were collected prospectively and we retrospectively collected efficacy data from the five French centres that participated in the Eribulin E7389-G000-398 expanded access program. Our main objectives were exploration of safety and analysis of eribulin efficacy (progression-free survival [PFS] and overall survival [OS]) according to sensitivity to the last microtubule-inhibiting agent administered.

Results

Median eribulin treatment duration was 3.3 months for the 250 patients included in this prospective single-arm study. Two hundreds and thirty-nine patients (95.6%) experienced an adverse event (AE) related to treatment including 129 (51.6%) with grade ≥ 3 AEs. The most frequently observed toxicities were cytopenias (59.6% of included patients), gastro-intestinal disorders (59.2%), and asthenia (56.4%). The most frequent grade 3-4 AE was neutropenia (37.2% with 4.8% febrile neutropenia). Median PFS and OS were 4.6 and 11.8 months, respectively. Patients classified as responders to the last microtubule-inhibiting therapy had a longer OS (hazard ratio [HR], 0.69; 95% confidence interval [CI], 0.51 to 0.94; p=0.017), and tended to display a better PFS (HR, 0.78; 95% CI, 0.58 to 1.04; p=0.086). OS improvement was still significant in multivariate analysis (adjusted HR, 0.53; 95% CI, 0.35 to 0.79; p=0.002).

Conclusion

This work based on a prospective study suggests that identification of patients likely to be more sensitive to eribulin could be based on their previous response to microtubules inhibitors.

hnRNP A1-mediated translational regulation of the G quadruplex-containing RON receptor tyrosine kinase mRNA linked to tumor progression

The expression and role of RNA binding proteins (RBPs) controlling mRNA translation during tumor progression remains largely uncharacterized. Analysis by immunohistochemistry of the expression of hnRNP A1, hnRNPH, RBM9/FOX2, SRSF1/ASF/SF2, SRSF2/SC35, SRSF3/SRp20, SRSF7/9G8 in breast tumors shows that the expression of hnRNP A1, but not the other tested RBPs, is associated with metastatic relapse. Strikingly, hnRNP A1, a nuclear splicing regulator, is also present in the cytoplasm of tumor cells of a subset of patients displaying exceedingly worse prognosis. Expression of a cytoplasmic mutant of hnRNP A1 leads to increased translation of the mRNA encoding the tyrosine kinase receptor RON/MTS1R, known for its function in tumor dissemination, and increases cell migration in vitro. hnRNP A1 directly binds to the 5′ untranslated region of the RON mRNA and activates its translation through G-quadruplex RNA secondary structures. The correlation between hnRNP A1 and RON tumoral expression suggests that these findings hold clinical relevance.