De-Escalation Strategies in Human Epidermal Growth Factor Receptor 2 (HER2)–Positive Early Breast Cancer (BC): Final Analysis of the West German Study Group Adjuvant Dynamic Marker-Adjusted Personalized Therapy Trial Optimizing Risk Assessment and Therapy Response Prediction in Early BC HER2- and Hormone Receptor–Positive Phase II Randomized Trial—Efficacy, Safety, and Predictive Markers for 12 Weeks of Neoadjuvant Trastuzumab Emtansine With or Without Endocrine Therapy (ET) Versus Trastuzumab Plus ET

Purpose

Human epidermal growth factor receptor 2 (HER2)–positive/hormone receptor (HR)–positive breast cancer is a distinct subgroup associated with lower chemotherapy sensitivity and slightly better outcome than HER2-positive/HR-negative disease. Little is known about the efficacy of the combination of endocrine therapy (ET) with trastuzumab or with the potent antibody-cytotoxic, anti-HER2 compound trastuzumab emtansine (T-DM1) with or without ET for this subgroup. The West German Study Group trial, ADAPT (Adjuvant Dynamic Marker-Adjusted Personalized Therapy Trial Optimizing Risk Assessment and Therapy Response Prediction in Early Breast Cancer) compares pathologic complete response (pCR) rates of T-DM1 versus trastuzumab with ET in early HER2-positive/HR-positive breast cancer.

Patients and Methods

In this prospective, neoadjuvant, phase II trial, 375 patients with early breast cancer with HER2-positive and HR-positive status (n = 463 screened) were randomly assigned to 12 weeks of T-DM1 with or without ET or to trastuzumab with ET. The primary end point was pCR (ypT0/is/ypN0). Early response was assessed in 3-week post-therapeutic core biopsies (proliferation decrease ≥ 30% Ki-67 or cellularity response). Secondary end points included safety and predictive impact of early response on pCR. Adjuvant therapy followed national standards.

Results

Baseline characteristics were well balanced among the arms. More than 90% of patients completed the therapy per protocol. pCR was observed in 41.0% of patients treated with T-DM1, 41.5% of patients treated with T-DM1 and ET, and 15.1% with trastuzumab and ET ( P < .001). Early responders (67% of patients with assessable response) achieved pCR in 35.7% compared with 19.8% in nonresponders (odds ratio, 2.2; 95% CI, 1.24 to 4.19). T-DM1 was associated with a significantly higher prevalence of grade 1 to 2 toxicities, especially thrombocytopenia, nausea, and elevation of liver enzymes. Overall toxicity was low; seventeen therapy-related severe adverse events (T-DM1 arms v trastuzumab plus ET; 5.3% v 3.1%, respectively) were reported.

Conclusion

The ADAPT HER2-positive/HR-positive trial demonstrates that neoadjuvant T-DM1 (with or without ET) given for only 12 weeks results in a clinically meaningful pCR rate. Thus, a substantial number of patients are spared the adverse effects of systemic chemotherapy.

Prospective WSG phase III PlanB trial: Final analysis of adjuvant 4xEC→4x doc vs. 6x docetaxel/cyclophosphamide in patients with high clinical risk and intermediate-to-high genomic risk HER2-negative, early breast cancer

504

Background: Optimal chemotherapy in HER2-negative, particularly HR-positive, early breast cancer (EBC), especially the survival impact of anthracyclines, is still a matter of debate. Retrospective analyses saw most benefit of 6xCEF vs. 6xCMF in HER2+ EBC. Prospective trials have shown conflicting results; no predictive molecular factors have been validated so far, particularly for HR+ EBC. The WSG PlanB trial is the first trial that randomized only patients with high clinical risk or with Recurrence Score >11 in the HR+/HER2- subgroup (pN0-1). Patients with RS<11 (pN0-1) had an excellent prognosis (five-year DFS of 94%) with endocrine therapy alone (Gluz et al. ASCO 2016). Methods: The WSG PlanB trial was originally planned as a non-inferiority study for comparison of 6 cycles of anthracycline-free TC (Arm A) vs. standard anthracycline-taxane based chemotherapy (4xEC→4xDoc) (Arm B) in patients with high-risk pN0 (T2-4, G2-3, <35 years, or high uPA/PAI-1) or pN+ HER2- EBC. Following an early amendment, Oncotype DX was performed in all HR+ tumors, and omission of chemotherapy (CT) was recommended in RS≤11 HR+ pN0-1 disease. Primary endpoint was DFS, defined as time to any recurrence, secondary cancer or death. Final analysis for the CT randomization was planned after completed 5-year follow-up in all patients. Results: From 2009 to 2011, PlanB enrolled 3198 patients (n=3073 with central pathology review). In 348 patients (15.3%), CT was omitted based on RS≤11. 2449 patients were randomized to 6xTC (n=1222) and 4xEC→4xDoc (n=1227). Within this cohort, 41% were pN+, 42% had G3 tumors and 18% HR-negative tumors by central pathology. After median follow-up of 61 months, very similar five-year DFS of 89.9% [88.1%-91.7%] vs. 90.2% [88.4%-92.0%] and five-year OS of 94.7% [93.4%-96.1%] vs. 94.6% [93.2%-96.0%] were observed in Arms A vs. B. Five treatment-related deaths were observed in Arm A (TC) vs. one in Arm B (EC-Doc) (0.4% vs. 0.1%), despite a trend to more SAE’s in Arm B vs. Arm A (n=397 vs. 358). Although recurrence score is a strong prognostic factor, it was not predictive for anthracycline efficacy; no efficacy differences between the study arms were observed in (locally) triple-negative patients or in those with >4 involved lymph nodes, despite the prognostic impact of these factors. Conclusion: In the WSG PlanB trial, patients with early HER2-negative BC seem to be sufficiently treated by six cycles of docetaxel/cyclophosphamide compared to four cycles of EC followed by four cycles of docetaxel -- no efficacy differences are evident in high-risk subgroups defined by triple-negative status, nodal status, or high Recurrence Score. Further prospective studies are urgently needed before final conclusions for impact of anthracyclines in HER2-negative BC can be drawn. Clinical trial information: NCT01049425.

Association of molecular subtype, proliferation, and immune genes with efficacy of carboplatin versus gemcitabine addition to taxane-based, anthracycline-free neoadjuvant chemotherapy in early triple-negative breast cancer (TNBC): Results of the randomized WSG ADAPT-TN trial

573

Background: In the ADAPT-TN neoadjuvant trial, 12-week nab-paclitaxel (nab- pac)+carboplatin (carbo) was highly effective and superior to nab-pac+gemcitabine (gem). However, within TNBC, reliable predictive markers for carbo use have yet to be identified. Methods: Patients with early TNBC (centrally confirmed) were treated by nab-pac 125 mg/m2 with either carbo AUC2 or gem 1000 mg/m2 d 1,8 q21 given for 4 cycles. Genomic data (80 genes) and Prosigna (PAM-50) scores were available in 306 pre-therapeutic samples of 331 treated patients. Fisher’s exact test was performed for pCR differences; associations of continuous measurements or scores with pCR were analyzed by the Mann-Whitney statistic. Results: pCR was 44.5% to 28.4% (p=.004) in favor of nab-pac - carbo. Specifically within the carbo- containing arm, immunological (CD8, PD1, PFDL1) genes and proliferation markers (proliferation score and ROR scores, MKI67, CDC20, NUF2, KIF2C, CENPF, EMP3, TYMS) were positively associated with pCR (p<.05 for all). Specifically within the gem-arm, angiogenesis genes were negatively associated with pCR (ANGPTL4: p=.05; FGFR4: p=.02; VEGFA: p=.03). In the whole collective, basal-like (83.3%) was favorable for pCR (38% vs. 20%, p=.015) compared to other subtypes (HER: 6.4%; luminal-A: 1.7%; normal: 8.7%), as was lower HER-2 score (p<.001). Proliferation was positively associated with pCR: i.e., Pam50 proliferation score, ROR scores (all p<.004), and higher Ki67 by central IHC (p<.001) -- though not MKI67 RNA expression, despite their moderate correlation. Conclusions: In early TNBC, basal-like subtype, higher Ki67 (by IHC), and lower HER-2 score were associated with chemo-sensitivity for both neoadjuvant arms. Chemo-resistance pathways differed between the two taxane-based combinations (low proliferation and immune marker gene expression for carbo, high angiogenesis for gem). The positive predictive impact of immunological genes in the nab-pac - carbo arm could influence optimal patient selection for immune-modulative therapy. Clinical trial information: NCT01815242.

Results of multicenter phase II WSG Neo-Predict trial: Predictive markers for evaluation of response to neoadjuvant paclitaxel+trastuzumab+lapatinib in HER2-positive early breast cancer

582

Background: Trastuzumab (T) and Lapatinib (L) containing neoadjuvant chemotherapy (NACT) increases pathological complete response (pCR) (vs. T or nihil) in HER2+ early breast cancer (EBC). Early clinical response markers (e.g. Ki67) in a 3-week biopsy or in residual tumor correlate with therapy efficacy and risk of relapse. This WSG Neo-Predict trial aimed to define early predictive markers for therapy response in a dual blockade (T+L) NACT setting. Methods: Patients with cT1c-cT4c HER2+ EBC were treated by paclitaxel (P) (80 mg/m2weekly) with L (750 mg p.o. daily) + T (2 mg/kg) weekly for 12 weeks. Adjuvant treatment with 4 cycles of Epirubicin/Cyclophosphamide (omission allowed in patients with pCR) and T for an additional 40 weeks was recommended. Primary objectives were pCR (ypT0/is/ypN0) and identification of a dynamic predictive test for pCR using a re-biopsy after three weeks of NACT (early response defined as central Ki67 decrease >30% (vs. baseline) and/or low cellularity (<500 invasive tumor cells)). Results: From 2013-2015, 64 patients (n=80 planned) were recruited. Overall pCR was 41% (41% for HER2+/HR+ (n=34) and 45.5% for HER2+//HR- (n=22)). A 0% pCR in the “non-responder” (n=7) group (vs. 50% in the “responder” (n=34) and 42% in the “missing response” (n=20) groups) is intriguing despite methodological limitations. Missing data for early response assessment in a substantial number of patients and negative DFS data from the ALTTO trial did not justify trial continuation. 27% of patients experienced severe adverse events (AE). 11.5% had > grade 3 AEs (including diarrhea, septic shock, leukopenia, and pneumonia). Conclusions: We observed a clinically meaningful pCR with moderate toxicity with only 12 weeks of paclitaxel weekly with dual HER2 blockade (T+L). Effect of additional chemotherapy in patients with pCR after 12 weeks of monochemotherapy remains questionable due to a strong prognostic effect of pCR in HER2+ EBC. In view of 0% pCR (by hypothesis-generating explorative analysis), a different treatment approach should be investigated in patients without “early response” by further prospective trials. Clinical trial information: 2012-003679-21.

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.

HER2 testing in gastric cancer diagnosis: Insights on variables influencing HER2-positivity from a large, multicenter, observational study in Germany

15

Background: HER2 testing is routine for metastatic gastric or gastroesophageal junction cancer (mGC/GEJC). Differing HER2-positivity rates are considered to be potential indicators of inter- and intra-laboratory deviations in testing quality. The influence of patient-, sample-, or method-related factors on HER2-positivity has not been assessed systematically. Methods: This observational, prospective study collected routine HER2 test result, patient- and tumor-related factors, sample source, and testing method data to identify factors influencing HER2-positivity rates in mGC/GEJC. Influencing factors were identified using stepwise multiple logistic regression and a statistical model was developed to predict probability of HER2-positivity. Institutes with deviations in HER2-positivity rates were identified by comparing 95% confidence intervals (CI) of documented and predicted rates. Results: From Jan 2013 to Dec 2015, data were collected from 2761 mGC/mGEJC routine diagnostic specimens at 50 pathology institutes in Germany. Final analyses included 2033 specimens with HER2 test results (1554 mGC and 479 mGEJC cases). Overall HER2-positivity rates across centers was 19.8% for mGC and 30.5% for mGEJC. Lauren classification showed the highest correlation with HER2-positivity, followed by HER2 testing rate, tumor location, type of sample (resection vs biopsy), and testing method (immunohistochemistry vs fluorescence in situ hybridization) (all P < .05). Four institutes were identified with predicted HER2-positivity rates outside the 95% CI of the documented rate. Conclusions: This is the first study to report on multifactorial parameters that impact HER2-positivity rates in routine mGC/GEJC diagnostics. Results suggest that effective assessment of HER2 testing quality based on positivity rates should consider tumor characteristics, testing rate, type of specimen, and testing method, as they affect HER2-positivity. As therapy options for HER2-positive mGC/GEJC continue to evolve, reliably identifying the right patients is key.

[HER2 testing in gastric cancer - results of a German expert meeting]

Valid HER2 testing is essential for optimal therapy of patients with HER2 positive gastric cancer and the correct use of first-line treatment. While each breast cancer is routinely being tested for the HER2 status, HER2 testing in gastric cancer has still not become part of the routine and is often only done upon request by the therapist. An interdisciplinary German expert group took the challenges of HER2 testing in gastric cancer as an opportunity to address essential aspects and questions for the practical use of HER2 testing in this indication from the perspective of pathologists and therapists. The recommendations made in this manuscript reflect the consensus of all participants and correspond to their opinions and long-term experience.

[Necrotizing funisitis : Histopathological indicator of occult congenital syphilis]

Congenital syphilis is a rare disease in central Europe. Placental changes may be non-specific but a typical finding is necrotizing funisitis of the umbilical cord. In a case report we describe how the histopathological incidental finding of B lymphocyte-rich, necrotizing funisitis led to the diagnosis of a previously unknown Treponema pallidum infection in parents and their newborn child. The pathological suspicion of congenital syphilis, although rare, has implications for the clinical management (serological evaluation of parents and child as well as the social environment, evaluation of viral coinfection and treatment decision) and is a notifiable disease.

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.

[Cytopathology in the diagnostics of hematological diseases]

Whereas in many fields of surgical pathology examination of cytological smears and analysis of histological tissue sections provide alternative methods which are chosen according to the clinical requirements, in hematopathology both types of morphological investigation are routinely applied in parallel and simultaneously. This procedure improves the diagnostic precision and safety. Unlike other European countries in Germany both procedures are performed by different specialties. Cytology is the responsibility of hematologists whereas histology is carried out by pathologists, which interferes with an integrative diagnostic approach unless intense communication takes place. Ideally, in the diagnosis of hematological disorders histology of bone marrow trephines should be studied in conjunction with smears of peripheral blood and bone marrow. In many instances, further complementary investigations, such as flow cytometry, cytogenetics and increasingly molecular pathological studies are necessary to guarantee an adequate modern state of diagnostics in hematopathology.

Comprehensive Molecular Profiling of Archival Bone Marrow Trephines Using a Commercially Available Leukemia Panel and Semiconductor-Based Targeted Resequencing

Comprehensive mutation profiling becomes more and more important in hematopathology complementing morphological and immunohistochemical evaluation of fixed, decalcified and embedded bone marrow biopsies for diagnostic, prognostic and also predictive purposes. However, the number and the size of relevant genes leave conventional Sanger sequencing impracticable in terms of costs, required input DNA, and turnaround time. Since most published protocols and commercially available reagents for targeted resequencing of gene panels are established and validated for the analysis of fresh bone marrow aspirate or peripheral blood it remains to be proven whether the available technology can be transferred to the analysis of archival trephines. Therefore, the performance of the recently available Ion AmpliSeq AML Research panel (LifeTechnologies) was evaluated for the analysis of fragmented DNA extracted from archival bone marrow trephines. Taking fresh aspirate as gold standard all clinically relevant mutations (n = 17) as well as 25 well-annotated SNPs could be identified reliably with high quality in the corresponding archival trephines of the training set (n = 10). Pre-treatment of the extracted DNA with Uracil-DNA-Glycosylase reduced the number of low level artificial sequence variants by more than 60%, vastly reducing time required for proper evaluation of the sequencing results. Subsequently, randomly picked FFPE samples (n = 41) were analyzed to evaluate sequencing performance under routine conditions. Thereby all known mutations (n = 43) could be verified and 36 additional mutations in genes not yet covered by the routine work-up (e.g., TET2, ASXL1, DNMT3A), demonstrating the feasibility of this approach and the gain of diagnostically relevant information. The dramatically reduced amount of input DNA, the increase in sensitivity as well as calculated cost-effectiveness, low hands on , and turn-around-time, necessary for the analysis of 237 amplicons strongly argue for replacing Sanger sequencing by this semiconductor-based targeted resequencing approach.