Nab-paclitaxel weekly versus dose-dense solvent-based paclitaxel followed by dose-dense epirubicin plus cyclophosphamide in high-risk HR+/HER2- early breast cancer: results from the neoadjuvant part of the WSG-ADAPT-HR+/HER2- trial

BACKGROUND

In high-risk hormone receptor-positive/human epidermal growth factor receptor 2-negative (HR+/HER2-) early breast cancer (EBC), nanoparticle albumin-bound (nab)-paclitaxel showed promising efficacy versus solvent-based (sb)-paclitaxel in neoadjuvant trials; however, optimal patient and therapy selection remains a topic of ongoing research. Here, we investigate the potential of Oncotype DX® recurrence score (RS) and endocrine therapy (ET) response (low post-endocrine Ki67) for therapy selection.

PATIENTS AND METHODS

Within the WSG-ADAPT trial (NCT01779206), high-risk HR+/HER2- EBC patients were randomized to (neo)adjuvant 4× sb-paclitaxel 175 mg/m2 q2w or 8× nab-paclitaxel 125 mg/m2 q1w, followed by 4× epirubicin + cyclophosphamide (90 mg + 600 mg) q2w; inclusion criteria: (i) cN0-1, RS 12-25, and post-ET Ki67 >10%; (ii) cN0-1 with RS >25. Patients with cN2-3 or (G3, baseline Ki67 ≥40%, and tumor size >1 cm) were allowed to be included without RS and/or ET response testing. Associations of key factors with pathological complete response (pCR) (primary) and survival (secondary) endpoints were analyzed using statistical mediation and moderation models.

RESULTS

Eight hundred and sixty-four patients received neoadjuvant nab-paclitaxel (n= 437) or sb-paclitaxel (n = 427); nab-paclitaxel was superior for pCR (20.8% versus 12.9%, P = 0.002). pCR was higher for RS >25 versus RS ≤25 (16.0% versus 8.4%, P = 0.021) and for ET non-response versus ET response (15.1% versus 6.0%, P = 0.027); no factors were predictive for the relative efficacy of nab-paclitaxel versus sb-paclitaxel. Patients with pCR had longer distant disease-free survival [dDFS; hazard ratio 0.42, 95% confidence interval (CI) 0.20-0.91, P = 0.024]. Despite favorable prognostic association of RS >25 versus RS ≤25 with pCR (odds ratio 3.11, 95% CI 1.71-5.63, P ≤ 0.001), higher RS was unfavorably associated with dDFS (hazard ratio 1.03, 95% CI 1.01-1.05, P = 0.010).

CONCLUSIONS

In high-risk HR+/HER2- EBC, neoadjuvant nab-paclitaxel q1w appears superior to sb-paclitaxel q2w regarding pCR. Combining RS and ET response assessment appears to select patients with highest pCR rates. The disadvantage of higher RS for dDFS is reduced in patients with pCR. These are the first results from a large neoadjuvant randomized trial supporting the use of RS to help select patients for neoadjuvant chemotherapy in high-risk HR+/HER2- EBC.

Significantly longer time to deterioration of quality of life due to CANKADO PRO-React eHealth support in HR+ HER2- metastatic breast cancer patients receiving palbociclib and endocrine therapy: Primary outcome analysis of the multicenter randomized AGO-B WSG PreCycle trial

BACKGROUND

The multicenter, randomized phase IV intergroup AGO-B WSG PreCycle trial (NCT03220178) evaluated the impact of CANKADO-based ePRO (electronic patient-reported outcomes) assessment on quality of life (QoL) in HR+ HER2- locally advanced or metastatic breast cancer (MBC) patients receiving palbociclib (P) and an aromatase inhibitor or P+fulvestrant. CANKADO PRO-React, an EU-registered medical device, is an interactive autonomous application reacting to patient self-reported observations.

PATIENTS AND METHODS

Between 2017 and 2021, 499 patients (median age 59 years) from 71 centers were randomized (2:1, stratified by therapy line) between an active version of CANKADO PRO-React (CANKADO-active arm) or a version with limited functionality (CANKADO-inform arm). 412 patients (271 CANKADO-active; 141 CANKADO-inform) were available for analysis of the primary endpoint, time to deterioration (TTD) of QoL (10-point drop on FACT-G), using an Aalen-Johansen estimator for cumulative incidence function of TTD DQoL with 95% pointwise confidence intervals (CI). Secondary endpoints included PFS, OS, and DQoL (QoL deterioration).

RESULTS

In all pts (ITT-ePRO), cumulative incidence of DQoL was significantly more favorable (lower) in the CANKADO-active arm (HR=0.698, 95%CI [0.506 - 0.963]). Among 1^stL patients (n=295), the corresponding HR was 0.716 (0.484-1.060; p=0.09), and in 2^ndL patients (n=117) it was 0.661 (0.374-1.168; p=0.2). Absolute patient numbers declined in later visits; FACT-G completion rates were 80% and higher until about visit 30; mean FACT-G scores showed steady decline from baseline and an offset in favor of CANKADO-active. No significant differences in clinical outcome were observed between arms: Median PFS (ITT population) was 21.4 (95%CI 19.4-23.7) (CANKADO-active) and 18.7 (15.1-23.5) months (CANKADO-inform); median OS was not reached (CANKADO-active) and 42.6 months (CANKADO-inform).

CONCLUSIONS

PreCycle is the first multicenter randomized eHealth trial demonstrating a significant benefit for MBC patients receiving oral tumor therapy when using an interactive autonomous patient empowerment application.

Strong impact of MammaPrint and BluePrint on treatment decisions in luminal early breast cancer: results of the WSG-PRIMe study

PURPOSE

The WSG-PRIMe Study prospectively evaluated the impact of the 70-gene signature MammaPrint® (MP) and the 80-gene molecular subtyping assay BluePrint® on clinical therapy decisions in luminal early breast cancer.

METHODS

452 hormone receptor (HR)-positive and HER2-negative patients were recruited (N0, N1). Physicians provided initial therapy recommendations based on clinicopathological factors. After prospective risk classification by MammaPrint/BluePrint was revealed, post-test treatment recommendations and actual treatment were recorded. Decisional Conflict and anxiety were measured by questionnaires.

RESULTS

Post-test switch (in chemotherapy (CT) recommendation) occurred in 29.1% of cases. Overall, physician adherence to MP risk assessment was 92.3% for low-risk and 94.3% for high-risk MP scores. Adherence was remarkably high in "discordant" groups: 74.7% of physicians initially recommending CT switched to CT omission following low-risk MP scores; conversely, 88.9% of physicians initially recommending CT omission switched to CT recommendations following high-risk MP scores. Most patients (99.2%) recommended to forgo CT post-test and 21.3% of patients with post-test CT recommendations did not undergo CT; among MP low-risk patients with pre-test and post-test CT recommendations, 40% did not actually undergo CT. Luminal subtype assessment by BluePrint was discordant with IHC assessment in 34% of patients. Patients' State Anxiety scores improved significantly overall, particularly in MP low-risk patients. Trait Anxiety scores increased slightly in MP high risk and decreased slightly in MP low-risk patients.

CONCLUSIONS

MammaPrint and BluePrint test results strongly impacted physicians' therapy decisions in luminal EBC with up to three involved lymph nodes. The high adherence to genetically determined risk assessment represents a key prerequisite for achieving a personalized cost-effective approach to disease management of early breast cancer.

Abstract GS5-06: No survival benefit of chemotherapy escalation in patients with pCR and “high-immune” triple-negative early breast cancer in the neoadjuvant WSG-ADAPT-TN trial

Background:Immune markers such as tumor infiltrating lymphocytes (TILs), CD8, PDL1, PD1 and other protein or mRNA-based genomic markers have been identified as prognostic / predictive in TNBC regarding survival / chemotherapy (CTx) efficacy.

In the adjuvant WSG-PlanB trial, patients with high TILs and/or CD8 by mRNA had excellent outcome, irrespective of anthracycline use; in the neoadjuvant ADAPT-TN trial, high PDL1, PD1 and CD8 and/or TILs were predictive for pCR. Still, optimal markers for potential treatment de-escalation have yet to be determined. Here, we analyse for the first time impact of immune mRNA-based markers and TIL's as prognostic and predictive survival markers.

Methods: TNBC patients (ER/PR<1%, HER2-,) were randomized to neoadjuvant 4x nab-paclitaxel 125 mg/m2/gemcitabine 1000 mg/m2 d1/8 q3w (gem arm) or 4x nab-paclitaxel 125 mg/m2/carboplatin AUC2 day 1/8 3-weekly (q3w) (carbo arm). Primary endpoint of WSG-ADAPT-TN was pCR (ypT0/is/ypN0); secondary endpoints included translational analyses, e.g., TILs or expression of 119 genes by nCounter platform. Standard adjuvant chemotherapy (4xEC) was optional (not randomized) in patients achieving pCR after 12 weeks. According to protocol, 1st safety survival analysis was performed after 3y median follow-up.

Results: Present translational analysis included 306 of 336 TNBC patients (36 months median FU). pCR was associated with significantly better survival (3y EFS: 92% vs. 71%, p<.001), but despite substantially higher pCR in the carbo arm (46% vs. 29%), no significant EFS advantage was seen (p=.6) (gem: 78%; carbo: 80%; 3y-EFS).

Bivariate Spearman correlations among CD8, PD1, and PDL1 were strongly positive; their correlations with TILs were moderately positive.

Preliminary Cox analysis of EFS was performed with clinical variables (cN, cT, menopausal status); neoadjuvant study arm; pCR; TILs; proliferation markers (baseline Ki67 by IHC, scores derived from PAM50); baseline immune markers; risk scores; and individual gene expression scores previously identified as prognostic for pCR in one or both neoadjuvant arms. Independent prognostic factors included pCR, cN, Ki67, PD1, and CD8; these were entered into (prognostic) interaction analysis. The resulting model contained cN, high Ki67 and low TILs as (unfavorable) main effects and the interaction of (higher) PD1*pCR (favorable).

Among pCR patients, the groups with/without additional adjuvant CTX were similar with respect to explanatory factors. Baseline TILs, Ki67, cN, and PD1 were entered into exploratory predictive analysis; the model retained only the interaction [adjuvant CTx * (fractionally ranked) PD1]. In patients with pCR, those with low PD1 benefited from standard anthracycline-containing adjuvant CTx, whereas patients high PD1 did not with an 98% 3y-EFS.

Conclusions: Our exploratory results suggest independent prognostic impact of mRNA markers and TIL's in early TNBC. Patients with both pCR (after 12 weeks) and “high-immune” signature (defined here by PD1) had excellent 3y-EFS and may be candidates for treatment de-escalation (e.g. omission of anthracyclines), whereas “low-immune” pCR patients may benefit from standard adjuvant poly-chemotherapy.

Citation Format: Gluz O, Nitz U, Liedtke C, Prat A, Christgen M, Feuerhake F, Garke M, Grischke E-M, Forstbauer H, Braun M, Warm M, Hackmann J, Uleer C, Aktas B, Schumacher C, Kuemmel S, Pelz E, Gebauer D, Paré L, Kates R, Wuerstlein R, Kreipe HH, Harbeck N. No survival benefit of chemotherapy escalation in patients with pCR and “high-immune” triple-negative early breast cancer in the neoadjuvant WSG-ADAPT-TN trial [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 GS5-06.

Neural Network Analysis of Follow-Up Data in Primary Breast Cancer

This paper reports on the performance of a recently developed neural network environment incorporating likelihood-based optimization and complexity reduction techniques in the analysis of breast cancer follow-up data with the goal of building up a clinical decision support system. The inputs to the neural network include classical factors such as grading, age, tumor size, estrogen and progesterone receptor measurements, as well as tumor biological markers such as PAI-1 and uPA. The network learns the structural relationship between these factors and the follow-up data. Examples of neural models for relapse-free survival are presented, which are based on data from 784 breast cancer patients who received their primary therapy at the Department of Obstetrics and Gynecology, Technische Universität München, Germany. The performance of the neural analysis as quantified by various indicators (likelihood, Kaplan-Meier curves, log-rank tests) was very high. For example, dividing the patients into two equally sized groups based on the neural score (i.e., cutoff = median score) leads to an estimated difference in relapse-free survival of 40% or better (80% vs. 40%) after 10 years in Kaplan-Meier analysis. Evidence for factor interactions as well as for time-varying impacts is presented. The neural network weights included in the models are significant at the 5% level. The use of neural network analysis and scoring in combination with strong tumor biological factors such as uPA and PAI-1 appears to result in a very effective risk group discrimination. Considerable additional comparison of data from different patient series will be required to establish the generalization capability more firmly. Nonetheless, the improvement of risk group discrimination represents an important step toward the use of neural networks for decision support in a clinical framework and in making the most of biological markers.

Long-Term Follow-Up Confirms Prognostic Impact of Pai-1 and Cathepsin D and L in Primary Breast Cancer

After long-term follow-up, the prognostic impact of the following proteolytic factors associated with tumor invasion and metastasis was evaluated in 276 primary breast cancer patients: uPA (urokinase-type plasminogen activator), PAI-1 (uPA inhibitor type 1), and cathepsins B, D and L. The median follow-up of patients still alive at the time of analysis was 109 months. To date 119 patients (43%) have relapsed and 117 (42%) have died. Antigen levels of uPA and PAI-1 were determined by ELISA in detergent extracts; cathepsin B, D, and L content was determined in cytosol fractions of the primary tumor: cathepsin D by ELSA and cathepsin B and L by ELISA.

In multivariate analysis (Cox model) for disease-free survival (DFS), lymph node status (p<0.001; RR=3.8), cathepsin L (p<0.001; RR=2.6) and PAI-1 (p=0.027; RR=1.7) were significant factors in all patients. In addition to these factors, grading was significant for overall survival (OS). In another multivariate approach, CART (Classification And Regression Trees) analysis, lymph node status (p<0.001) turned out to be the strongest discriminator for patients at high risk of relapse. In the node-negative patient subset, PAI-1 was the strongest risk group discriminator (p<0.001): in this subset, patients with low levels of both PAI-1 and cathepsin D had a very low relapse rate of only 3.2% compared to 39% in the remaining node-negative patients. In node-positive patients cathepsin L gave the best risk group assessment (p=0.001).

In conclusion, tumor-associated PAI-1 and cathepsins D and L provide significant, statistically independent prognostic information for DFS and OS in primary breast cancer, even after a median follow-up period of almost 10 years.

Abstract P6-13-01: Withdrawn

This abstract was withdrawn by the authors.

Abstract P2-10-03: Genomic markers but not molecular subtypes provide prognostic impact and predict anthracycline efficacy in early triple-negative breast cancer: Results from the prospective WSG PlanB trial

Background: Optimal treatment, particularly use of anthracyclines in aggressive triple-negative breast cancer (TNBC), is still a controversial issue in early BC management. However, TNBC exhibits substantial molecular heterogeneity: for example, the immune phenotype seems to be associated with better outcome. An important clinical issue in early TNBC is to quantify the impact of subtypes as well as individual genes on survival and especially on anthracycline benefit.

Methods: In PlanB, patients with ER and PR&lt;1% (local or central lab), HER2- EBC were treated by TC (6 cycles Docetaxel/Cyclophosphamide) or EC-Doc (4xEpirubicin/Cyclophosphamideà4xDocetaxel) (overall n=2449, HER2-). RNA isolation was successfully performed in n=402/449 patients with available follow-up. Gene (n=119) expression data by Nanostring® platform were entered into univariate and multivariate Cox models for disease-free survival (DFS) to identify genes (and combinations) with potential prognostic and/or predictive impact. Median follow-up was 60 months.

Results: RNA expression results were available in n=394 (203 TC vs. 191 EC-Doc): PAM-50 subtype: basal-like 82%; HER2-enriched 7%; luminal (A or B) 3.5%; normal-like 7.4%. Median age was 54; 78% were node-negative. In patients with “discordant” tumors (HR positive by local or central assessment), 76% were still basal-like, compared to 86% in “concordant” TNBC. Of 27 patients with HER2-enriched subtype, HER2 status was positive by central assessment in only five cases (18%).

Within this TN cohort, 5y DFS was similar in TC (83%) and EC-Doc (79%) arms; positive nodal status and tumor size &gt;2 cm were (unfavorable) clinical-pathological prognostic markers. Prognostic or predictive impacts of molecular subtype, risk of recurrence subgroups, or proliferation indices were not seen.

Twelve genes (incl. CD8, EGFR, GPR160, SPINT2) showed potential multivariate prognostic impact by entering the “forwards stepwise” multivariate Cox model for DFS. The upper half of patients according to the resulting “twelve-gene signature” had well over 90% 5y-DFS, whereas the lowest quartile had under 60% 5-y DFS. Several genes (incl. ERBB2, FOXC1) showed potential for a predictive impact regarding TC vs. EC-Doc by interaction analysis. Further details and perspectives for testing the robustness of these potential impacts will be presented at the meeting.

Conclusions

To our knowledge, these are the first results from a prospective, adjuvant taxane-based trial regarding molecular predictors of anthracycline efficacy and PAM-50-based prognostic factors in early TNBC. ERBB2 expression, but not HER2-enriched subtype, was predictive for A-benefit in HER2-negative BC. Molecular heterogeneity of TNBC beyond basal-like vs. non-basal-like subtype is clinically relevant and should be considered for patient stratification in ongoing trials with combination therapy. The identified prognostic gene signature should be validated in the WSG-ADAPT-TN and other TNBC trials.

Citation Format: Gluz O, Liedtke C, Prat A, Christgen M, Gebauer D, Kates R, Pelz E, Clemens M, Warm M, Aktas B, Kuemmel S, Pare L, Krabisch P, Kreipe HH, Wuerstlein R, Nitz U, Harbeck N. Genomic markers but not molecular subtypes provide prognostic impact and predict anthracycline efficacy in early triple-negative breast cancer: Results from the prospective WSG PlanB trial [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 P2-10-03.

Abstract P1-06-06: No age-related outcome disparities according to 21-gene recurrence score groups in early breast cancer patients treated by adjuvant chemotherapy in the prospective WSG PlanB trial

Background: Elderly breast cancer (BC) patients (pts) have been reported to have worse BC-related outcome than younger pts, even within clinical trials such as TEAM. Shak et al. recently showed in a large SEER data analysis that in the high 21-gene recurrence score (RS) group, older pts (&gt;70y) receive less chemotherapy (CT) and have a worse BC-specific mortality than younger pts. Here, we therefore aimed to see whether there are age-related outcome disparities according to RS groups in pts receiving state-of-the-art CT in the prospective WSG PlanB trial.

Material and Methods: PlanB compared 6 cycles of anthracycline-free TC vs. standard anthracycline-taxane based CT (4xECà4xDoc) in patients with high risk pN0 (T2-4, G2-3, &lt;35 years, or high uPA/PAI-1) or pN+ HER2- early BC. 21-gene assay was performed in all HR+ tumors and omission of chemotherapy (CT) recommended in RS≤11 HR+ pN0-1 BC. Final analysis for the CT randomization for RS 12-25 after 60 months median follow-up revealed similar 5-year DFS and OS outcomes for both CT arms (ASCO 2017).

Results: In all pts with luminal cancer and RS results (n=2577), there was an age-related significant difference in RS risk group assignment (p&lt;0.0001): in young pts (&lt;40y), 9.1% had RS≤11, 52.7% RS 12-25, and 38.2% RS&gt;25; in pts 40-69 years, 18.3% had RS≤11, 61% RS 12-25, and 20.7%% RS&gt;25; in elderly pts (&gt;70y), 19.5% had RS≤11, 55.3% RS 12-25, and 25.2% RS&gt;25. Among patients receiving chemotherapy, RS&gt;25 vs. RS&lt;25 was associated with significantly poorer DFS separately within the elderly subgroup (HR=3.03, 95%-CI [1.15-7.96]) and in those aged 40-69 years (HR=3.14, 95%-CI [2.18-4.52]); there were only nine events among patients &lt;40y. In particular, among pts receiving CT with RS&gt;25, there were no significant differences in DFS between any two of these three age groups.

Conclusion: A substantial percentage of elderly patients (&gt; 70y) presents with high-risk luminal disease; these patients are candidates for CT. In PlanB, about 25% of elderly luminal BC patients had high-risk (RS&gt;25) tumors. Nevertheless, after receiving modern adjuvant CT, their DFS was comparable to that of non-elderly pts with high-risk RS tumors. Consequently, older BC pts with high-risk luminal tumors who are fit enough to receive adjuvant CT should be treated according to guidelines in order to overcome age-dependent survival disparities which have been observed in registries for high-RS tumors.

Citation Format: Harbeck N, Gluz O, Wuerstlein R, Clemens M, Malter W, Reimer T, Nuding B, Stefek A, Pollmanns A, Augustin D, Uleer C, Lorenz-Salehi F, Shak S, Chao C, Christgen M, Kates R, Kreipe H, Nitz U. No age-related outcome disparities according to 21-gene recurrence score groups in early breast cancer patients treated by adjuvant chemotherapy in the prospective WSG PlanB trial [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 P1-06-06.

De-escalation strategies in HER2-positive early breast cancer (EBC): final analysis of the WSG-ADAPT HER2+/HR- phase II trial: efficacy, safety, and predictive markers for 12 weeks of neoadjuvant dual blockade with trastuzumab and pertuzumab ± weekly paclitaxel

BACKGROUND

Response rates in HER2-overexpressing EBC treated with neoadjuvant chemotherapy and trastuzumab (T) have been improved by addition of pertuzumab (P). The prospective, phase II, neoadjuvant WSG-ADAPT HER2+/HR- trial assessed whether patients with strong early response to dual blockade alone might achieve pathological complete response (pCR) comparable to that of patients receiving dual blockade and chemotherapy.

PATIENTS AND METHODS

Female patients with HER2+/HR- EBC (M0) were randomized (5:2) to 12 weeks of T + P ± weekly paclitaxel (pac) at 80 mg/m2. Early response was defined as proliferation decrease ≥30% of Ki-67 (versus baseline) or low cellularity (<500 invasive tumor cells) in the 3-week biopsy. The trial was designed to test non-inferiority for pCR in early responding patients of the T + P arm versus all chemotherapy-treated patients.

RESULTS

From February 2014 to December 2015, 160 patients were screened, 92 were randomized to T + P and 42 to T + P+pac. Baseline characteristics were well balanced (median age 54 versus 51.5 years, cT2 51.1 versus 52.4%, cN0 54.3 versus 61.9%); 91.3% of patients completed T + P per protocol and 92.9% T + P+pac. The pCR rate in the T + P+pac arm was 90.5%, compared with 36.3% in the T + P arm as a whole. In the T + P arm, 24/92 were classified as non-responders, and their pCR rate was only 8.3% compared with 44.7% in responders (38/92) and 42.9% in patients with unclassified early response (30/92). No new safety signals were observed in the study population.

CONCLUSION

Addition of taxane monotherapy to dual HER2 blockade in a 12-week neoadjuvant setting substantially increases pCR rates in HER2+/HR- EBC compared with dual blockade alone, even within early responders to dual blockade. Early non-response under dual blockade strongly predicts failure to achieve pCR.

Abstract P1-09-05: The role of immune and apoptosis markers for prediction of pCR in the WSG-ADAPT HER2+/HR+ phase II trial evaluating 12-weeks of neoadjuvant TDM1 ± endocrine therapy (ET) versus T + ET in HER2-positive hormone-receptor-positive early breast cancer (EBC)

Background: Immune and apoptosis biomarkers are potential prognostic/predictive markers in HER2+ EBC. High PD-L1 expression was shown to be predictive for lower pCR after chemotherapy+trastuzumab+/-pertuzumab, particularly in HER2+, ER- disease. Yet, HER2+ EBC co-expressing hormone receptors is a distinct entity.

The ADAPT HER2+/HR+ phase II trial (n=376) compared 12 weeks of neoadjuvant T-DM1 + ET vs. trastuzumab (T)+ET and demonstrated pCR rates of about 41% in both (well tolerated) T-DM1 arms.

Methods: In order to identify potential early predictors for pCR (i.e. no invasive tumor in breast and lymph nodes), immune markers (PDL1 on infiltrating immune cells (IIC) and on tumor cells (TC); CD8 in invasive margin and in tumor center) and apoptosis markers (bcl-2; mcl-2) were determined by immunohistochemistry (IHC; H-scores) in core biopsy sections obtained at primary diagnosis and at cycle 2. For multivariate logistic regression, each biomarker (separately), clinical factors (Ki-67, cT, cN) and therapy were entered. All analyses were exploratory.

Results:Biomarkers were available in up to 326 patients (pts) at baseline and up to 170 pts at 3 weeks (due to low tumor content in 2nd core biopsy).

Baseline IIC-PDL1 was associated with pCR in the T-DM1 arm (OR 2.89; 95%CI: 1.11-7.51); IIC-PDL1 at cycle 2 was not associated with pCR.

PD-L1 expression in TC was rare (2%); cycle-2 TC-PD-L1 was associated with pCR in all pts and in the pooled TDM-1 arms.

High baseline CD8 in tumor center was associated with pCR in the whole cohort (OR 2.4; CI: 1.04 – 5.5) and in the T+ET arm (OR=10.1; CI: 1.12 - 91.6) and at cycle 2 in all pts (OR=9.52; CI: 2.17 – 41), in pooled TDM-1 arms (OR=15.7; CI: 2.49 – 99), and in TDM-1+ET (OR=25.05; CI: 2.12 – 295). Increases in this marker also predicted pCR in all pts, pooled TDM-1, and in TDM-1+ET. Association of cycle-2 CD8 in tumor center with pCR persisted in multivariate models.

Lower baseline CD8 in invasive margin was associated with pCR in the T-DM1 arm (OR=0.09; CI: 0.01-0.69), but at cycle 2 in all pts (OR=18.1; CI: 1.60 – 204) and in pooled TDM-1 arms (OR=23.5; CI: 1.1 - 500). This positive impact persisted in multivariate models.

Bcl-2 expression at baseline was associated with non-pCR in all pts (OR=0.28, CI: 0.12 - 0.66), in the pooled T-DM1 arms (OR=0.216, CI: 0.08 - 0.61), and particularly in the T-DM1+ET arm (OR=0.14; CI: 0.03 - 0.71). This association persisted in multivariate analysis. At cycle 2, lower bcl-2 had OR=0.16 (CI: 0.03 - 0.96) in the pooled T-DM1 arms. No association with efficacy was seen for mcl-1.

Conclusions: The WSG-ADAPT HER2+/HR+ phase II trial is the first international trial to focus on HER2+/HR+ EBC alone and the first to show substantial pCR rates of &gt; 40% after only 12 weeks of T-DM1 -- without standard chemotherapy.

Expression of bcl-2 may affect resistance to T-DM1. High immune activity at baseline and/or cycle 2 seems to be associated with pCR. The association of CD8 expression and its changes with therapy efficacy is complex and could depend on ET.

Further biomarker analyses are ongoing and will be presented at the meeting.

Citation Format: Harbeck N, Nitz UA, Matthias C, Kates R, Braun M, Kümmel S, Schumacher C, Potenberg J, Kraemer S, Kleine-Tebbe A, Augustin D, Aktas B, Forstbauer H, Tio J, Liedtke C, Grischke E-M, de Haas SL, Deurloo R, Schumacher J, Wuerstlein R, Kreipe HH, Gluz O. The role of immune and apoptosis markers for prediction of pCR in the WSG-ADAPT HER2+/HR+ phase II trial evaluating 12-weeks of neoadjuvant TDM1 ± endocrine therapy (ET) versus T + ET in HER2-positive hormone-receptor-positive early breast cancer (EBC) [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 P1-09-05.

The West German Study Group Breast Cancer Intrinsic Subtype study: a prospective multicenter decision impact study utilizing the Prosigna assay for adjuvant treatment decision-making in estrogen-receptor-positive, HER2-negative early-stage breast cancer

PURPOSE

The West German Study Group (WSG) Breast Cancer Intrinsic Subtype (BCIST) study was designed to assess the influence of Prosigna gene signature assay results on physicians' adjuvant treatment recommendations by determining the extent of change in pre-test treatment recommendations following assay results. Secondary objectives were to assess the influence of Prosigna results on physicians' confidence in their therapeutic recommendations and on patients' decisional conflict status, anxiety levels, and functional status.

METHODS

This prospective, observational, decision impact study enrolled consecutive postmenopausal patients with estrogen-receptor (ER)-positive, HER2-negative, lymph-node-negative early-stage breast cancer in 11 centers in Germany. Physicians based their pre-test adjuvant treatment recommendations on standard clinico-pathological parameters. Tumor specimens were assayed using the Prosigna test in a WSG central pathology laboratory following manufacturer's guidelines. An independent pathology laboratory performed subsequent Prosigna assays on tumor sections to assess assay result concordance with the central laboratory. Physicians completed treatment confidence questionnaires prior to and after receiving Prosigna test results. Patients completed standardized questionnaires on decisional conflict, anxiety, and health status both before and after Prosigna testing.

RESULTS

The present study population consisted predominantly of low-to-intermediate risk patients (N = 198). Prosigna had 29.3% discordance in intrinsic subtyping with local immunohistochemistry test results. After Prosigna test results, a change in the adjuvant therapy recommendation occurred in 36 (18.2%) patients; 22 (11.1%) patients switched from no chemotherapy to chemotherapy. After Prosigna test results, physicians expressed increased confidence in their prognostic assessment in 87.9% of patients, and increased confidence in their treatment recommendation in 89.4%. Patients reported improved anxiety and emotional/functional well-being after receiving Prosigna test results.

CONCLUSIONS

Use of the Prosigna assay led to a change in 18.2% of adjuvant treatment decisions. Prosigna testing was associated with increased patient and physician confidence in treatment decisions, and with decreased patient anxiety and improved well-being. Any comparison of the therapeutic decision-making impacts of different genomic assays must account for potential confounding factors.

Comparison of prognostic and predictive impact of genomic or central grade and immunohistochemical subtypes or IHC4 in HR+/HER2- early breast cancer: WSG-AGO EC-Doc Trial

INTRODUCTION

Potential prognostic and predictive markers in early, intermediate-risk breast cancer (BC) include histological grade, Ki-67, genomic signatures, e.g. genomic grade index (GGI), and intrinsic subtypes. Their prognostic/predictive impact in hormone receptor (HR: ER and/or PR) positive/HER2- BC is controversial. WSG-AGO EC-Doc demonstrated superior event-free survival (EFS) in patients with 1-3 positive lymph node receiving epirubicin/cyclophosphamide-docetaxel (EC-Doc) versus 5-fluoruracil/epirubicin/cyclophosphamide (FEC).

METHODS

In a representative trial subset, we quantify concordance among factors used for clinical chemotherapy indication. We investigate the impact of central histology (n = 772), immunohistochemistry for intrinsic subtyping and IHC4, and dichotomous (GG) or continuous (GGI) genomic grade (n = 472) on patient outcome and benefit from taxane chemotherapy, focusing on HR+/HER2- patients (n = 459).

RESULTS

Concordance of local grade (LG) with central (CG) or genomic grade was modest. In HR+/HER2- patients, low (GG-1: 16%), equivocal (GG-EQ: 17%), and high (GG-3: 67%) GG were associated with respective 5-year EFS of 100%, 93%, and 85%. GGI was prognostic for EFS within all LG subgroups and within CG3, whereas IHC4 was prognostic only in CG3 tumors.In unselected and HR+/HER2- patients, CG3 and luminal-A-like subtype entered the multivariate EFS model, but not IHC4 or GG. In the whole population, continuous GGI entered the model [hazard ratio (H.R.) of 75th versus 25th = 2.79; P = 0.01], displacing luminal-A-like subtype; within HR+/HER2- (H.R. = 5.36; P < 0.001), GGI was the only remaining prognostic factor.In multivariate interaction analysis (including central and genomic grade), luminal-B-like subtype [HR+ and (Ki-67 ≥20% or HER2+)] was predictive for benefit of EC-Doc versus FEC in unselected but not in HR+/HER2- patients.

CONCLUSION

In the WSG-AGO EC-Doc trial for intermediate-risk BC, CG, intrinsic subtype (by IHC), and GG provide prognostic information. Continuous GGI (but not IHC4) adds prognostic information even when IHC subtype and CG are available. Finally, the high interobserver variability for histological grade and the still missing validation of Ki-67 preclude indicating or omitting adjuvant chemotherapy based on these single factors alone.

TRIAL REGISTRATION

The WSG-AGO/EC-Doc is registered at ClinicalTrials.gov, NCT02115204.

Abstract P2-07-01: Association of TILs with clinical parameters, recurrence score, and prognosis in patients with early HER2-negative breast cancer (BC) – A translational analysis of the prospective WSG planB trial

Introduction:

Tumor-infiltrating lymphocytes (TILs) have been associated with prognosis and with chemotherapy response among patients with BC, particularly in presence of high-risk features. The WSG planB trial randomized 2448 patients with HER2- N0/1 BC for comparison of anthracycline-free (6xTC) vs. standard anthracycline-taxane chemotherapy (4xEC-4xDoc). Recurrence Score® (RS) was incorporated for risk stratification in hormone receptor positive (HR+) BC. The present analysis focuses on the correlation of TILs with clinical/pathological parameters and their prognostic impact among planB patients.

Methods:

Stromal TILs were evaluated using a pathologist and two-observer approach. Three independent observers evaluated digital sections on H&E staining as previously suggested (Salgado et al., Ann Oncol. 2014); the median of the three values (TILmed) was used for statistical analysis. Spearman correlations of TILmed with clinical/pathological parameters (including central KI67 expression, quantitative ER measurements, nodal involvement, and RS) and univariate impact on event-free survival (EFS) were analyzed.

Results:

Our analysis included 300 patients with HR- and 1124 patients with HR+ HER2- BC. Both in HR- and HR+ BC, a significant association between TILmed and (i) central grading (correlation coefficient r=0.147, p=0.012 and r=0.195, p&lt;0.001, respectively) and (ii) central Ki67 expression (r=0.202, p=0.001 and r=0.152 and p&lt;0.001) was observed. Among HR+ cases, a significant association between TILmed and quantitative ER measurements (r=-0.412, p=0.041) and RS (r=0.190, p&lt;0.001) was found. Furthermore, univariate Cox analysis revealed a significant association between TILmed (coded as fractional rank) and event-free survival (EFS). The hazard ratio of 75th to 25th percentile was 1.58 (95%CI: 1.06-2.36, p=0.025). This impact was not separately significant in HR subgroups due to lack of events

Conclusion:

In this dataset, presence of stromal TILs was moderately associated with clinical features of high-risk breast cancer (including RS) and decreased EFS. TILs will be evaluated as a prognostic or predictive factor (in multivariate and subgroup analyses) when the outcome results are evaluated after prolonged follow up. Furthermore, an updated analysis including the complete planB dataset will be presented.

Citation Format: Liedtke C, Gluz O, Heinisch F, Feuerhake F, Kreipe HH, Clemens M, Nuding B, Kraemer S, Reimer T, Svedman C, Shak S, Nitz U, Kates RE, Harbeck N, Christgen M. Association of TILs with clinical parameters, recurrence score, and prognosis in patients with early HER2-negative breast cancer (BC) – A translational analysis of the prospective WSG planB trial. [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 P2-07-01.

Abstract P1-13-01: Comparison of 12 weeks neoadjuvant Nab-paclitaxel combined with carboplatinum vs. gemcitabine in triple- negative breast cancer: WSG-ADAPT TN randomized phase II trial

Background: Pathological complete response (pCR) is associated with improved prognosis in TNBC, but optimal chemotherapy remains unclear. Use of weekly nab- paclitaxel (Nab-Pac) vs. conventional paclitaxel and also addition of carboplatinum(Carbo) to anthracycline-taxane(A/T) containing chemotherapy results in significantly higher pCR rates in TNBC with unclear impact on survival and increased toxicity.

The ADAPT study seeks to compare Carbo vs. gemcitabine(Gem) added to nab- paclitaxel as a short 12-week A-free regimen. It also assesses efficacy in early responders vs. non-responders by 3-week proliferation and/or imaging response.

Methods: ADAPT TN compares 12-week neoadjuvant regimens: Carbo vs. Gem combined with Nab-Pac and aims to identify early-response markers for pCR (yPN0 and ypT0/is). TNBC patients (centrally confirmed ER/PR &lt;1%, HER2 neg.), cT1c- cT4c, cN0/+ were randomized to arm A (Nab-Pac 125/Gem 1000 d1,8 q3w) vs. B (Nab-Pac 125/Carbo AUC2 d1,8 q3w). Randomization was stratified by center and nodal status. The trial is powered for pCR comparison by therapy arm and by presence vs. absence of early response markers. Pre-planned interim analysis aimed to identify a dynamic biomarker, e.g. drop of 3-week Ki-67, and to validate trial assumptions.

Results: 336 patients were enrolled from 47 centers between 06/13-02/15 (n=182 ArmA: Nab-Pac/Gem and n=154 ArmB: Nab-Pac/Carbo). 90% and 95% completed therapy according to protocol respectively (n.s.). Median age was 50y. At baseline: A/B: 73% and 74%% had G3 tumors, median Ki-67 of 70% and 75%; 62.6% and 62.9%% had cT2-4c tumors, pN0 status prior to chemotherapy was confirmed in 50.5% and 50%, respectively.

pCR (ypT0/is/ypN0) was A: 28.7% and B: 45.9% (p&lt;0.001). Total pCR (ypT0/ypN0) was A: 25.8% and B: 45.2% respectively (p &lt;0.001).

Nab/Gem arm was associated with significantly higher frequency of dose reductions (20.6% vs. 11.9% (p=0.03), treatment related SAE's (13% vs. 5%, p=0.02), grade 3-4 infections (6.1% vs. 1.3%, p=0.04) and ALAT elevations (11.7 vs. 3.3%, p=0.01) compared to the Nab-Carbo arm.

Within the planned interim analysis (n=130: A/B: 69/61), baseline Ki-67 (Nab- Pac/Carbo arm), age&gt;50 years, and low cellularity (&lt;500 tumor cells and/or Ki-67≤10% in the 3-week biopsy) (Nab-Pac/Gem arm) were positively associated with pCR by logistic regression analysis (separately by therapy arm). In all patients, therapy arm itself was significant for pCR.

Validation of responder definitions for the whole study will be presented at the meeting.

Conclusions:

This is the first large randomized study comparing two short 12-week anthracycline- free regimens in unselected TNBC. Our results suggest superior efficacy and excellent toxicity of Nab-Pac/Carbo vs. Gem. Longer A/T-Carbo containing regimens render quite comparable pCR rates, thus overtreatment by 4xEC in unselected TNBC may be present in some patients. Early response criteria seem to differ according to regimen; their assessment may be impaired by substantial tumor necrosis already after the first therapy cycle.

Citation Format: Gluz O, Nitz U, Liedtke C, Christgen M, Sotlar K, Grischke EM, Forstbauer H, Braun M, Warm M, Hackmann J, Uleer C, Aktas B, Schumacher C, Bangemann N, Lindner C, Kuemmel S, Clemens M, Potenberg J, Staib P, Kohls A, Pelz E, Kates RE, Wuerstlein R, Kreipe HH, Harbeck N. Comparison of 12 weeks neoadjuvant Nab-paclitaxel combined with carboplatinum vs. gemcitabine in triple- negative breast cancer: WSG-ADAPT TN randomized phase II trial. [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 P1-13-01.

Final results from the prospective phase III WSG-ARA trial: impact of adjuvant darbepoetin alfa on event-free survival in early breast cancer

BACKGROUND

WSG-ARA plus trial evaluated the effect of adjuvant darbepoetin alfa (DA) on outcome in node positive primary breast cancer (BC).

PATIENTS AND METHODS

One thousand two hundred thirty-four patients were randomized to chemotherapy either with DA (DA+; n = 615) or without DA (DA-; n = 619). DA (500 µg q3w) was started at hemoglobin (Hb) levels <13.0 g/dl (<12 g/dl after DA label amendment) and stopped at Hb levels ≥14.0 g/dl (12 g/dl after label amendment). Primary efficacy end point was event-free survival (EFS); secondary end points were toxicity, quality of life (QoL) and overall survival (OS).

RESULTS

Venous thrombosis (DA+: 3.0%, DA-: 1.0%; P = 0.013) was significantly higher for DA+, but not pulmonary embolism (0.3% in both arms). Median Hb levels were stable in DA+ (12.6 g/dl) and decreased in DA- (11.7 g/dl). Hb levels >15 g/dl were reported in 0.8% of cycles. QoL parameters did not significantly differ between arms. At 39 months, DA had no significant impact on EFS (DA+: 89.3%, DA-: 87.5%; Plog-rank = 0.55) or OS (DA+: 95.5%, DA-: 95.4%; Plog-rank = 0.77).

CONCLUSIONS

DA treatment did not impact EFS or OS in routine adjuvant BC treatment.

Abstract P5-04-02: Biopsy of metastases impacts treatment choice and patient outcome in breast cancer – Final results of the WSG/DETECT PRIMET study

Background: Changes in tumor biology (e.g., hormone receptor (HR) / HER2 status or grading) between primary tumor (PT) and metastatic tissue (MT) could impact outcome and treatment choice following first recurrence in breast cancer (BC).

Methods: PRIMET is a prospectively planned, retrospective multicenter quality assurance study comparing BC phenotype in tissue from PT, involved lymph nodes (LN) of primary disease, and disease recurrence (DR). PRIMET comprises 635 patients from WSG and DETECT trial groups (11 centers), whose BC was diagnosed between 1980 and 2010; follow-up continued until mid-2012. Patients with unilateral primary BC suffering subsequent local-regional and / or distant DR (LDR / DDR) were included. Clinical data including ER, PR, HER2, and grade were obtained from a systematic chart review in PT and DR; in two centers, these factors were also measured in LN by central pathology. Dependence of post-recurrence survival (PRS) on changes in tumor biological factors was analyzed.

Results: Data from 635 patients (including 592 cM0, of whom 46% had LDR only) were available for analysis. Median follow-up in patients alive at analysis was 101 months. Considering cM0 patients, median overall survival (OS) was 176 months; median recurrence-free survival (RFS) was 48 months (DDR present: 45 months; LDR only: 50 months). Median PRS was 59 months (DDR present: 45 months; LDR only: 127 months). In patients with first DR within 18 months, median PRS was 29 months, in others 79 months. HR status in PT/MT was: 61.5% (+/+), 13.2% (+/-), 5.5% (-/+) 19.8% (-/-). Of the HR “switches” in either direction with LN biopsy available, about half already occurred in lymph nodes. HER2 status in PT/MT was: 14.6% (+/+), 6.7% (+/-), 14.9% (-/+) 63.8% (-/-). With LN biopsy available, most losses of HER2 overexpression were already observed in LN tissue, whereas acquired HER2 overexpression was observed in about half of LN biopsies. Triple negative (TN: HR-, HER2-) percentages were 74.4% (non-TN/non-TN), 9.0% (non-TN/TN), 6.1% (TN/non-TN), 10.5% (TN/TN).

Compared to HR+/+, loss of HR+ status (HR+/-) was significantly associated with poorer PRS (hazard ratio: 1.62; p = 0.01). Significantly better PRS was associated with a switch from G3 to G1/2 (hazard ratio: 0.47; p = 0.02). Tumors that switched to TN or that lost HER2 overexpression showed trends toward poorer PRS. Persistent TN was associated with poorer PRS than other combinations.

Among patients with DDR, metastasis in bone only was associated with better PRS than primary or visceral (CNS, lung, liver, etc.) metastasis. Among patients with visceral metastasis, negative HR status in metastasis was associated with poorer survival than in HR+/+ not only for HR-/- (p = 0.02), but also for HR+/- (p = 0.04).

Conclusions:

Tumor biology of primary and metastatic tissue differed in a substantial fraction of patients (HR: 19%; HER2: 22%, TN: 18%); more than half of all changes occurred already in LN. Status changes particularly loss of HR+ status, had significant prognostic impact. We can expect a switch in HR or HER2 status (or both) in about 38% of metastatic tissue biopsies, with presumably important clinical therapeutic consequences, in particular regarding targeted therapies.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-04-02.

Abstract P6-05-11: Run-in phase of prospective WSG-ADAPT HR+/HER2- trial demonstrates feasibility of early endocrine sensitivity prediction by recurrence score and conventional parameters in clinical routine

Background: Despite promising evidence regarding outcome prediction, endocrine sensitivity, as determined by proliferation response to short-term preoperative endocrine therapy, is currently not included in adjuvant chemotherapy decisions in early HR+/HER2- breast cancer (BC).

Methods: The prospective WSG-ADAPT HR+/HER2- trial includes early BC patients with 0-3 positive LN who are candidates for adjuvant chemotherapy based on clinical-pathological criteria alone; it aims to spare chemotherapy in a substantial proportion utilizing a combination of genomic assessment by Oncotype DX and endocrine sensitivity testing. All patients received 3-week preoperative endocrine induction therapy (ET): aromatase inhibitors (AI) if postmenopausal, tamoxifen if premenopausal. Patients with low (0-11) Recurrence Score (RS) or intermediate RS (12-25) and ET response (centrally tested, post-therapy Ki-67 &lt;10%) are recommended to forego adjuvant chemotherapy (“low-risk” patients). Distribution of RS, responder percentages in each group, and impacts of RS, ET regimen, and initial Ki-67 on post-therapy Ki-67 are reported here.

Results: As of 6/2013, 380 patients from 30 study centers had been enrolled in the ADAPT HR+/HER2- trial. Median age was 54 years. At first pre-planned analysis (5/2013), paired Ki-67 measurements (pre-/post-therapy) were available in 241 patients; RS was available in 208 cases (201 with paired Ki-67). RS was low in 21.6%, intermediate in 57.7%, and high in 20.7%; the respective risk group responder percentages (post-treatment Ki 67 &lt;10%) were 84.1%, 73.9%, and 40.0% (p&lt;0.001 when comparing low/intermediate vs. high, chi-square). In particular, these percentages support the pre-trial estimate of &gt;70% endocrine responders in the intermediate genomic risk group, who could potentially be spared adjuvant chemotherapy. Median Ki 67 level decreases (as percentage of pre-treatment value) were 25% in premenopausal patients (tamoxifen, n = 101) vs. 75% in postmenopausal patients (AI, n = 115) (p&lt;0.001, Mann-Whitney); median decreases by RS group were similar, 61% (low), 53% (intermediate) and 56% (high), respectively (p = 0.81, Kruskal-Wallis). In linear regression, pre-treatment Ki-67, endocrine regimen/menopausal status, and RS were all independent predictors for post-treatment Ki 67. Final run-in-phase analysis and validation will be presented after completion of endocrine induction therapy in 400 patients.

Conclusions: The Run-In Phase of the WSG ADAPT HR+/HER2- trial confirms trial design estimates of RS and proliferation response to induction ET. It indicates that the multicenter prospective ADAPT concept combining static and dynamic biomarker assessment for individualized therapy decisions in early BC is feasible. Proliferation response was strongly associated with therapy group (AI/post-menopausal vs. tamoxifen/pre-menopausal). Survival non-inferiority of intermediate Recurrence Score proliferation responders vs. low Recurrence Score patients (active control) will be tested in the ADAPT main phase to determine if adjuvant chemotherapy can be spared in 70% of patients with 0-3 positive LN classified as “intermediate risk” by conventional factors.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-05-11.

P1-06-03: Predictive Value of HER2, Topoisomerase-II (Topo-II) and Tissue Inhibitor of Metalloproteinases (TIMP-1) for Efficacy of Taxane-Based Chemotherapy in Intermediate Risk Breast Cancer – Results from the EC-Doc Trial

Background: Despite extensive research, there is still no consensus on optimal predictors for use of taxane-based chemotherapy (cht) in early breast cancer. Some studies have revealed HER2 as a significant predictive marker for efficacy of taxanes and anthracyclines. TIMP-1 and Topo-II are reported to be predictive for anthracycline efficacy. In our previous reports, both Ki-67≥20% and central G3 status emerged as significant predictors for taxane benefit. We have now compared HER2 and Topo-II (as protein expression and gene amplification) and TIMP-1 immunoreactivity as well as factor combinations (HT (HER2/TIMP-1) and 2T (Topo-II/TIMP-1) regarding their predictive value for benefit from taxane-based cht.

Methods: The EC-Doc trial randomized 1950 patients with 1–3 positive LN to 6x CEF/CMF vs. 4xEC-4xDoc. Significantly better DFS and OS favoring EC-Doc have been previously reported (Nitz et al., SABCS 2008). Protein expression and gene amplification data as well central histology/grade were available for 772 patients. Survival analysis was performed using Cox proportional hazards and Kaplan-Meier statistics. Analysis of HER2 survival impact status was prospectively planned.

Results: The entire and the investigated study populations did not differ regarding baseline characteristics. After median follow up of 64 months, both DFS (5y 90% vs. 80%, p=0.006) and OS (5y 95% vs. 92%, p=0.022) rates significantly favored EC-Doc vs. CEF in this cohort as well. HER2 over-expression (3+ and/or FISH≥2.0) was reported in 158 tumors (20%), Topo-II aberration (deletion or amplification) was reported in 78 (49.4%) HER2+ and in 83 (13.6%) HER2−negative tumors; 496 tumors were classified as TIMP-1 immunoreactive (65.2%). None of these factors were significantly prognostic for EFS in this collective. Regarding DFS, EC-Doc was strongly superior to FEC in HER2+ tumors (HR=0.29, 95%CI: 0.12−0.7, p=0.006) but not in HER2− tumors (p=0.18). In Topo-II aberrated tumors, the benefit of EC-Doc was remarkably strong (HR=0.28, 95% CI: 0.11−0.69, p=0.006), whereas the benefit was not significant in Topo-II normal tumors (p=0.16), which comprise more than ¾ of the total. In contrast, Topo-II protein overexpression (&gt;10%) was not associated with a stronger benefit in either subgroup. The superiority of EC-Doc to FEC was significant in the larger group of TIMP-1 immunoreactive tumors (HR=0.57, p=0.025) but not in TIMP-1 negative tumors (p=0.14), similar behavior was seen in “HT” and “2T” subgroups (significance with HR about 0.5 in the “+” subgroups). In a multivariate model for DFS including age, tumor size, Ki-67, central grade, HR, HER2, TOPO_II aberration, TIMP-1 status, therapy and interactions of all these factors with therapy arm, the only significant therapy interaction was that of (high) Ki-67 (HR=0.76, 95% CI: 0.59−0.98, p=0.03); significant main effects in this model were age, central grade, and Ki-67.

Conclusions: These data suggest predictive significance for Topo-II aberration, TIMP immunoreactivity and HER2 over-expression as well as a multivariate predictive significance of high Ki-67 for enhanced benefit of taxane-based cht.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-06-03.

Abstract P2-09-14: Evidence for Predictive and Prognostic Impact of Molecular Classification in Taxane-Based Chemotherapy in Intermediate Risk Breast Cancer — An Analysis of the WSG EC-Doc Trial

Background: Patients with hormone receptor positive breast cancer (BC) and 1-3 positive lymph nodes (LN) belong to the intermediate risk-group. Among these patients chemoendocrine therapy may be considered. The prognostic role of molecular breast cancer subgroups and their predictive impact regarding taxane-and anthracycline based chemotherapy is unclear. This analysis evaluated the ability of molecular subtypes to predict outcome after standard FEC or EC-Doc chemotherapy in pts with 1-3 positive LN.

Methods: The EC-Doc trial randomized 2012 patients with 1-3 positive LN to 6x FEC/CMF vs. 4x EC followed by 4 x docetaxel (Doc). Significantly better DFS and OS in favor of EC-Doc was reported previously (Nitz et al., SABCS 2008). Protein expression data and central histology/grade (G) were available for 772 patients (Control n=390; EC-Doc n=382). Protein expression was measured on tissue micro arrays for ER, PR, Her2 (both IHC/FISH), Ki-67, Ck 5/6, and EGFR. Molecular subgroups were classified using ki-67 cutt-off of 13.25 % (Cheang et al. JNCI 2009). Results: There was no difference in baseline characteristics (age, LN, grade, tumor size, HR) between the entire ITT-study population and the investigated cohort of 772 pts. There were significantly more G 3 tumors in the basal and Her2 group and more G 1/2 tumors in the luminal A cohort. Distribution of molecular subtypes is as follows:

- Luminal A: HR+ (ER and/or PR+), low KI-67 and Her2-: 26.1%

- Luminal B: HR+ and either Ki-67 high or Her2+: 44.8%

- Her2: HR-and Her2+: 10.9%

- Triple negative (TN) basal-like ER/PR/Her2- ; Ck 5/6+ and/or EGFR+: 11.8%

- TN non-basal-like: TNBC; both Ck 5/6 and EGFR-: 6.4%

After median follow up of 64 months, both DFS (5y 90% vs. 80%, p=0.006) and OS (5y 95% vs. 92%, p=0.022) rates also significantly favored EC-Doc vs. FEC in this cohort. DFS rates were highest in luminal A and lowest in TN basal-like tumors.

In univariate analysis a significant benefit of EC-DOC vs. FEC for DFS is seen in luminal B patients (p=0.004; HR=0.41; (0.22-0.77)). EC-Doc was also better than FEC in HR-patients who were not “basal-like (p=.057; HR=0.385 (0.14 — 1.07).

In multivariate analysis including age, nodal status, tumor size, molecular subtypes, and chemotherapy regimen age, luminal A subtype, and interaction of EC-Doc and luminal B subtype (HR=0.44) influenced significantly DFS survival. Conclusions: These data provide evidence that molecular subtypes are associated with both different levels of benefit from EC-Doc and different DFS within each treatment group. These retrospective results will be validated within the prospective WSG PlanB trial.

Table/Figure 1: multivariate model for DFS

Tabid Parameters bssdciated with benefitfrctm EC-Dgccompared to CEF in a multivariate tnofiel tor DFS

Abstract P4-06-22: Persistent Triple-Negative Phenotype Is Associated with Poorest Outcome among Patients with Metastatic Breast Cancer (BC) - Results of the Retrospective Multicenter PriMet Study Comparing Molecular BC Phenotypes in Primary Tumors and Corresponding Recurrences

Background: Patients with triple negative (TN) breast cancer (BC), defined by lack of both ER/PR expression and HER2 overexpression, have an unfavorable prognosis. Although phenotype changes between primary tumor (PT) and disease recurrence (DR) have been described, their clinical significance is still unclear.

Methods: We conducted PriMet, a retrospective multicenter (n=11) study to compare BC phenotype in PT and corresponding DR. Inclusion criteria comprised (1) unilateral BC with subsequent/synchronous local/regional/distant DR and (2) immunohistochemical confirmation of DR. Our aim was to (a) evaluate discordance rates between PT/DR, (b) find predictors for discordance, and (c) analyze the impact of discordance on patient outcome.

Results: 436 patients were entered into PriMet; 414 had no evidence of primary metastatic disease (M0). Median follow-up in patients alive at time of analysis was 73. 1 (4.4-293.6) months. Triple receptor status for PT and DR was available in 377 patients; 68 patients (18.0 %) showed TNBC in PT, 40 patients (10.6 %) had TNBC in both PT and DR (i.e. TNBC persistence); 28 patients (7.4 %) changed from TNBC to non-TNBC (15 became HER2 positive (4.0 %)). Status changes for ER and PR were significantly positively associated (P&lt;0.001). Patients with either persistent TNBC or non-TNBC had a median age at diagnosis of 52.0 compared to 55.5 yrs for patients with discordant TN status (p=0.04). Compared to differing constellations, persistent TNBC was associated with higher tumor grade (p=0.018) as well as with both decreased disease-free survival (DFS) (see figure) and post-recurrence survival (PRS) in M0 patients. In multivariate analysis containing pT stage, nodal stage, tumor grade in PT, TNBC in PT and TNBC persistence, TNBC persistence remained significantly associated with decreased DFS and PRS.

Conclusion: PriMet provides substantial evidence regarding potential phenotype changes in PT vs. DR and underlines the importance of immunohistochemical DR verification even in initially TN disease. TNBC persistence was significantly associated with adverse patient outcome.

Impact of expression differences of kallikrein-related peptidases and of uPA and PAI-1 between primary tumor and omentum metastasis in advanced ovarian cancer

BACKGROUND

Primary tumor levels of serine proteases of the kallikrein-related peptidases (KLK) family as well as urokinase-type plasminogen activator (uPA) and its inhibitor PAI-1 impact disease course in ovarian cancer. The changes in levels of these factors from primary tumor to omentum metastasis ('level differentials') could thus be associated with metastastic processes.

PATIENTS AND METHODS

Protein levels of seven tissue KLK (KLK5-8, 10, 11, 13), uPA, and PAI-1 were determined in extracts of primary tumor tissue and corresponding omentum metastasis of 54 ovarian cancer patients.

RESULTS

Higher level differentials of KLK5-8, 10-11, and uPA were associated with residual tumor >10 mm. Residual tumor and larger level differentials of KLK5-7, 10, and uPA were associated with disease progression in the whole cohort. Remarkably, level differentials of KLK5-8 and 10-11 strongly impacted disease progression even in patients with residual tumor mass ≤10 mm; hence, the observed impact of level differentials in KLK5-7 and 10 on disease progression was not simply attributable to their association with surgical success.

CONCLUSION

Since they impact both surgical outcome and survival in advanced ovarian cancer, measurement of level differentials could support clinical decisions on surgical and systemic therapy or help in patient selection for novel targeted therapies.

Impact of tumor biology, particularly triple-negative status, on response to pre-operative sequential, dose-dense epirubicin, cyclophosphamide followed by docetaxel in breast cancer

BACKGROUND

The central objective of this study was to determine the predictive impact of several established tumor biological factors (PgR, ER, HER2 and Ki-67) on response to pre-operative chemotherapy in primary breast cancer.

PATIENTS AND METHODS

59 primary M0 breast cancer patients received pre-operative sequential dose-dense epirubicin and cyclophosphamide followed by docetaxel (19 patients at dosage 100 mg/m(2), 40 patients at 75 mg/m(2)).

RESULTS

Pathological complete remission (pCR) occurred in 17 patients (29%) and at least partial remission in 42 (71%). Higher proliferation (Ki-67) and lack of hormone receptors (either or both) were significant predictive factors for pCR; moreover, 8/11 (73%) patients with triple-negative tumors (HER2(-)/ER(-)/PgR(-)) had pCR (p=0.001). Breast conserving surgery was achieved in 46/59 patients (78%). Hand-foot syndrome occurred in 12/19 patients treated at the higher docetaxel dosage but only 1/40 of the remaining patients. Higher docetaxel dosage was associated with improved pCR in the non-triple-negative subgroup.

CONCLUSION

The tumor biology of hormone receptor-negative, especially triple-negative, and highly proliferating breast cancer is associated with strongly positive response to dose-dense, pre-operative epirubicin/cyclophosphamide/docetaxel chemotherapy.

Outcome Prediction in Node-Negative Breast Cancer Based on ASCO-Recommended Biomarkers uPA/PAI-1 Using the Final 10-Year Analysis of the Randomized Multicenter Chemo N0 Trial Compared to Adjuvant Online™

Background: Based on interim analysis of Chemo N0, the first prospective multicenter randomized clinical trial using biomarkers uPA/PAI-1 for risk stratification and chemotherapy selection in N0 breast cancer, uPA/PAI-1 are now recommended for routine use by ASCO and AGO guidelines. Final 10-year follow-up of Chemo N0 has validated the clinically relevant long-term prognostic and predictive impact of uPA/PAI-1 in N0 breast cancer. To quantify the clinical utility of this impact, outcomes in subgroups defined by these biomarkers were compared to predictions of Adjuvant Online™, the leading validated tool based on established clinical factors. Methods: In Chemo N0, patients (n=647, 1993-98) were prospectively stratified according to uPA/PAI-1: High-risk patients were randomized (6x CMF vs. observation), low-risk patients observed. Retrospectively, we divided recruited patients into two groups (chemotherapy vs. no adjuvant therapy) and stratified using uPA/PAI-1 (low vs. high). Individual 10-year OS was calculated by www.adjuvantonline.org (Version 7.0); these estimated values were compared to the observed Chemo N0 10-year OS. Results: 383/647 patients have complete 10-year follow-up data. Median 10-year OS estimated by Adjuvant Online™ was 80.5% taking into account administered adjuvant therapy; 10-year Chemo N0 follow-up revealed observed 10-year OS of 74.7% (97/383 died). 77.8% (298/383) did not receive chemotherapy: In high-risk, untreated patients (n=137), 10-year OS was 72.3% vs. estimated 81.1%. In CMF-treated patients (all high-risk, n=85), observed OS was 61.2% vs. estimated 76.4%. Conclusions: For the first time, risk assessment by novel biomarkers is compared to that by Adjuvant Online™ in final data from a randomized prospective clinical trial. In patients with high uPA/PAI-1, the individual 10-year risk calculated by Adjuvant Online™ seems to be underestimated compared to observed patient outcome. Tumor-biological information provided by validated biomarkers thus has the potential of enhancing epidemiology-based risk estimation using only established factors.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 4038.

Interim analysis of the multicenter phase II HEDON trial evaluating pathological response to pre-operative docetaxel and docetaxel+trastuzumab (T) in locally advanced breast cancer (BR) stratified by HER2-status

e11512

Background: Docetaxel is the most effective mono-substance in metastatic BC and highly effective in adjuvant chemotherapy. Early docetaxel-monotherapy data in primary systemic therapy (PST) showed a pCR of 18% (Amat et al; 2003), comparable with pCR-rates of standard PST combination chemotherapy. HEDON was conducted to evaluate efficacy of docetaxel ± T with regard to pCR (defined as absence of invasive and non-invasive BC in breast and lymph nodes) as primary endpoint; secondary endpoints were safety, breast conservation rate and 5-yr DFS. Additionally Trans-HEDON includes a translational research program to identify molecular RNA and methylation (DNA) based markers of response to docetaxel-monotherapy. Methods: From 2006 until 2008, the multicenter phase II HEDON trial fully recruited 93 pts, with therapy still ongoing; tumor stages: T2 (23), T3 (11), T4 (5); nodal status: N0 (16), N1–2 (23). Arm A: Docetaxel (100 mg/m2x6) in HER2-negative (n=60) and Arm B: Docetaxel (100 mg/m2x6) in combination with T (18x2mg/kg KG) preoperatively in HER2-overexpressed BC (n=33), followed by surgery and then by adjuvant epirubicin/cyclophosphamide (E90Cx4), radiotherapy if indicated, T for altogether one year, and endocrine therapy in ER+ and/or PgR+ BC. Pre-planned interim analysis (safety and efficacy) was performed after recruitment of 39 pts (Arm A 26, Arm B 13). Results: In Arm A, 7 pts. (26.9%) achieved pCR and 9 pts. (34.6%) pPR. In Arm B, 7 pts. (53.8%) achieved pCR and all 6 others (46.2%) pPR. Neutropenia occurred in 11 pts. (8 with grade 3). Moderate (25%) dose reduction was necessary in 13 pts., and 50% dose reduction in one patient. Conclusion: According to interim analysis of the HEDON trial, docetaxel-monotherapy of 6 cycles at 100mg/m2 q21 (plus T in HER2-positive BC) is an effective and safely administrable PST. There were no unexpected toxicities, and preliminary pCR rates in HER2-neg (26.9%) and HER2-pos (53.8%) pts. were comparable to those of combination chemotherapy. These interim results will be completed by final analysis on the full collective, with molecular predictors from TransHEDON hopefully identifying patients who derive extensive benefit.

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Results of the German fulvestrant in practice evaluation programme to evaluate the efficacy, safety, tolerability and acceptance of fulvestrant under daily routine conditions

Abstract #6132

Material and Methods: Fulvestrant is an estrogen receptor (ER) antagonist with a distinct mode of action used in the treatment of postmenopausal women with advanced breast cancer progressing or recurring on an antiestrogen. 848 postmenopausal women with ER+ advanced mamma carcinoma, relapsed during or after adjuvant anti-estrogene treatment, or with a disease progression under an anti-estrogene therapy, were enrolled in this Fulvestrant In Practice Evaluation Programme (IPEP). Under daily routine conditions and without intervention by the sponsor regarding selection of subjects, diagnostic procedures or therapeutic decisions relevant data of the fulvestrant therapy was documented over a period of 9 months. Results: The median patient age was 64 years, 52 % of patients had a co-morbidity, 78 % one or more prior palliative therapies. Efficacy: Clinical benefit was observed in 627/848 patients, including 62 complete and 177 partial remissions. Best response was delayed in 115 patients (not seen at 3 months but at 6 months). Estimated 9-month overall survival (OS) was 89%; 9-month event-free survival (EFS) was 71%. Safety: 244 non-serious adverse events by patient were recorded, most commonly General disorders and administration site conditions, gastrointestinal and musculo-sceletal symptoms. Excluding deaths, 7 serious adverse events were recorded (none attributed to fulvestrant); no new or unexpected safety issues arose. 20 patients died during observation. Tolerability: Tolerability was judged as good to very good by the majority of both specialists and patients with stable values at 3, 6 and 9 months. Acceptance of injection: The vast majority of both doctors and patients found the application via injection to be acceptable or very acceptable, the handling was judged by the doctors as mostly good to very good. Conclusion: Fulvestrant treatment was well tolerated and well accepted in this palliative patient collective, no new safety findings occurred. The treatment showed good efficacy with any patient, who had achieved disease stabilization or better after three months being likely to gain survival benefit from prolonged Fulvestrant therapy. Best response often occured delayed.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 6132.

YB-1 expression and effectiveness of different dose-intensification strategies in high-risk breast cancer: Five-year follow-up results of prospective randomized WSG-AM-01 trial

563

Background: Y-box binding protein (YB-1), known as oncogenic transcription factor, is associated with up-regulation of MDR1, alters p53 function, and induces growth of an aggressive phenotype. In high-risk breast cancer, the prospective randomized WSG-AM-01 trial has reported significantly better event-free (EFS) and overall survival (OS) for tandem high-dose (HD) vs. dose-dense (DD) chemotherapy, especially in basal-like und HER2 subgroups. The present study examines the interaction of a drug resistant phenotype induced by YB-1 within the WSG-AM-01 collective at 5-year follow-up. Methods: 236 tumors (116 HD/120 DD) of 403 randomized patients (60%) were available for construction of tissue microarrays and determination of molecular classification by k-clustering of expression of 34 protein markers. Immunostaining of YB-1 by specific peptide antibody was scored semiquatitatively by intensity. Associations of YB-1 staining with other protein expression factors were studied by Pearson correlations. Univariate survival was estimated by Kaplan-Meier analysis and tested by log rank statistics. Multivariate survival modeling was performed by a generalized Cox model, with linear proportional hazards terms in the first block and time-varying interactions in the second block. Results: At a median follow-up of 61.7 months, the WSG-AM-01 confirms a significant EFS and OS benefit for HD in HRBC. In 60% of tumors, there was strong YB-1 expression. YB-1 was significantly associated with several proliferation and drug resistance markers, such as p53, EGFR, S6 and with basal-like/Her2 subtypes.YB-1 expression was highly predictive for response to HD: both EFS (HR=0.29, p=0.001) and OS (HR=0.16, p=0.0001) were significantly improved by HD compared to DD for YB-1 positive tumors; these favorable time-varying hazard ratios signify decreases in early (≤3 years) relapses and deaths, respectively. Conclusions: Among all investigated markers, only YB-1 expression was significantly associated by time- varying interaction analysis with efficacy of HD. The results suggest YB-1 as a potential stratification criterion for future trials as well as a target for treatment of drug resistant HRBC.

No significant financial relationships to disclose.

FGFR4 Arg388 allele is associated with resistance to adjuvant therapy in primary breast cancer

625

Background: Bange et al. recently found that a single-nucleotide polymorphism (SNP) at codon 388 of fibroblast growth factor receptor 4 (FGFR4) gene, causing a transmembrane domain missense mutation (Gly388Arg), is associated with outcome in node-positive breast cancer. Methods: This study addresses clinical relevance of this SNP, FGFR4 genotype, phenotype, and HER2 regarding patient outcome and influence of adjuvant systemic therapy in a substantial primary breast cancer collective (n=372; 1987–2002), median follow-up 94.5 months. Treatment was administered according to consensus recommendations at the time: 73 patients (all N0) received no adjuvant systemic therapy; 114 received adjuvant chemotherapy (87% CMF-based), 164 tamoxifen, 10 combined chemo-endocrine therapy, 11 unknown. 128 (36%) patients experienced disease recurrence, 104 (81%) distant relapses; 140 (38%) died. PCR-RFLP-analysis of germ-line polymorphism was performed in uninvolved lymph nodes; FGFR4 and HER2 expression were assessed immunohistochemically in tumor tissue arrays. Primary endpoint was DFS, since it best reflects impact of adjuvant systemic therapy. Results: In 51% of patients, homo- or heterozygous Arg388 allele was present. No correlation existed between FGFR4 genotype and expression or HER2 status. In N0 patients, FGFR4 genotype was not correlated with disease outcome. In N+ patients, however, FGFR4 Arg388 was significantly associated with poor DFS (p=0.02) and OS (p=0.04). Notably, this association seems to be attributable to relatively poor therapy response in Arg388 carriers, reflected in their significantly shorter DFS (p=0.02) and OS (p=0.045) among patients receiving adjuvant systemic therapy. It is also seen as a significant interaction term in a multivariate proportional hazards model with Arg388 carriers having only about half as much benefit from adjuvant systemic therapy as wild-type carriers. Conclusions: Our results show that the previously found association of FGFR4 Arg388 genotype with breast cancer progression is strongest in patients with adjuvant systemic therapy, particularly chemotherapy, and thus may reflect therapy resistance.

No significant financial relationships to disclose.