Efficacy of Endocrine Therapy Plus Trastuzumab and Pertuzumab vs De-escalated Chemotherapy in Patients with Hormone Receptor-Positive/ERBB2-Positive Early Breast Cancer: The Neoadjuvant WSG-TP-II Randomized Clinical Trial

Importance

Combination of chemotherapy with (dual) ERBB2 blockade is considered standard in hormone receptor (HR)-positive/ERBB2-positive early breast cancer (EBC). Despite some promising data on endocrine therapy (ET) combination with dual ERBB2 blockade in HR-positive/ERBB2-positive BC, to our knowledge, no prospective comparison of neoadjuvant chemotherapy vs ET plus ERBB2 blockade in particular with focus on molecular markers has yet been performed.

Objective

To determine whether neoadjuvant de-escalated chemotherapy is superior to endocrine therapy, both in combination with pertuzumab and trastuzumab, in a highly heterogeneous HR-positive/ERBB2-positive EBC.

Design, Setting, and Participants

This prospective, multicenter, neoadjuvant randomized clinical trial allocated 207 patients with centrally confirmed estrogen receptor-positive and/or progesterone receptor-positive (>1%) HR-positive/ERBB2-positive EBC to 12 weeks of standard ET (n = 100) vs paclitaxel (n = 107) plus trastuzumab and pertuzumab. A total of 186 patients were required to detect a statistically significant difference in pathological complete response (pCR) (assumptions: 19% absolute difference in pCR; power, ≥80%; 1-sided Fisher exact test, 2.5% significance level).

Interventions

Standard ET (aromatase inhibitor or tamoxifen) or paclitaxel, 80 mg/m2, weekly plus trastuzumab and pertuzumab every 21 days.

Main Outcomes and Measures

The primary end point was pCR (ypT0/is, ypN0). Secondary end points included safety, translational research, and health-related quality of life. Omission of further chemotherapy was allowed in patients with pCR. PAM50 analysis was performed on baseline tumor biopsies.

Results

Of the 207 patients included (median [range] age, 53 [25-83] years), 121 (58%) had cT2 to cT4 tumors, and 58 (28%) had clinically node-positive EBC. The pCR rate in the ET plus trastuzumab and pertuzumab arm was 23.7% (95% CI, 15.7%-33.4%) vs 56.4% (95% CI, 46.2%-66.3%) in the paclitaxel plus trastuzumab and pertuzumab arm (odds ratio, 0.24; 95% CI, 0.12-0.46; P < .001). Both immunohistochemical ERBB2 score of 3 or higher and ERBB2-enriched subtype were independent predictors for pCR in both arms. Paclitaxel was superior to ET only in the first through third quartiles but not in the highest ERBB2 quartile by messenger RNA. In contrast with the paclitaxel plus trastuzumab and pertuzumab arm, no decrease in health-related quality of life after 12 weeks was observed in the ET plus trastuzumab and pertuzumab arm.

Conclusions and Relevance

The WSG-TP-II randomized clinical trial is, to our knowledge, the first prospective trial comparing 2 neoadjuvant de-escalation treatments in HR-positive/ERBB2-positive EBC and demonstrated an excellent pCR rate after 12 weeks of paclitaxel plus trastuzumab and pertuzumab that was clearly superior to the pCR rate after ET plus trastuzumab and pertuzumab.

Trial Registration

ClinicalTrials.gov Identifier: NCT03272477.

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.

De-Escalated Neoadjuvant Trastuzumab-Emtansine With or Without Endocrine Therapy Versus Trastuzumab With Endocrine Therapy in HR+/HER2+ Early Breast Cancer: 5-Year Survival in the WSG-ADAPT-TP Trial

PURPOSE

Neoadjuvant chemotherapy is standard of care in human epidermal growth factor receptor 2-positive (HER2+) early breast cancer (EBC), irrespective of the hormone receptor status. Trastuzumab-emtansine (T-DM1), antibody-drug conjugate, is highly effective in HER2+ EBC; however, no survival data are available for de-escalated antibody-drug conjugate-based neoadjuvant therapy without conventional chemotherapy.

PATIENTS AND METHODS

In the WSG-ADAPT-TP (ClinicalTrials.gov identifier: NCT01779206) phase II trial, 375 centrally reviewed patients with hormone receptor-positive (HR+)/HER2+ EBC (clinical stage I-III) were randomly assigned to 12 weeks of T-DM1 with or without endocrine therapy (ET) or trastuzumab + ET once every 3 weeks (ratio 1:1:1). Adjuvant chemotherapy (ACT) omission was allowed in patients with pathologic complete response (pCR). In this study, we report the secondary survival end points and biomarker analysis. Patients who received at least one dose of study treatment were analyzed. Survival was analyzed using the Kaplan-Meier method, two-sided log-rank statistics, and Cox regression models stratified for nodal and menopausal status. P values < .05 were considered statistically significant.

RESULTS

T-DM1, T-DM1 + ET, and trastuzumab + ET induced similar 5-year invasive disease-free survival (iDFS; 88.9%, 85.3%, 84.6%; P_log-rank = .608) and overall survival rates (97.2%, 96.4%, 96.3%; P_log-rank = .534). Patients with pCR versus non-pCR had improved 5-year iDFS rates (92.7% v 82.7%; hazard ratio, 0.40; 95% CI, 0.18 to 0.85). Among the 117 patients with pCR, 41 did not receive ACT; 5-year iDFS rates were similar in those with (93.0%; 95% CI, 84.0 to 97.0) and without ACT (92.1%; 95% CI, 77.5 to 97.4; P_log-rank = .848). Translational research revealed that tumors with PIK3CA wild type, high immune marker expression, and luminal-A tumors (by PAM50) had an excellent prognosis with de-escalated anti-HER2 therapy.

CONCLUSION

The WSG-ADAPT-TP trial demonstrated that pCR after 12 weeks of chemotherapy-free de-escalated neoadjuvant therapy was associated with excellent survival in HR+/HER2+ EBC without further ACT. Despite higher pCR rates for T-DM1 ± ET versus trastuzumab + ET, all trial arms had similar outcomes because of mandatory standard chemotherapy after non-pCR. WSG-ADAPT-TP demonstrated that such de-escalation trials in HER2+ EBC are feasible and safe for patients. Patient selection on the basis of biomarkers or molecular subtypes may increase the efficacy of systemic chemotherapy-free HER2-targeted approaches.

Impact of RNA Signatures on pCR and Survival after 12-Week Neoadjuvant Pertuzumab plus Trastuzumab with or without Paclitaxel in the WSG-ADAPT HER2+/HR- Trial

PURPOSE

To identify associations of biological signatures and stromal tumor-infiltrating lymphocytes (sTIL) with pathological complete response (pCR; ypT0 ypN0) and survival in the Phase II WSG-ADAPT HER2+/HR- trial (NCT01817452).

EXPERIMENTAL DESIGN

Patients with cT1-cT4c, cN0-3 HER2+/HR- early breast cancer (EBC) were randomized to pertuzumab+trastuzumab (P+T, n = 92) or P+T+paclitaxel (n = 42). Gene expression signatures were analyzed in baseline biopsies using NanoString Breast Cancer 360 panel (n = 117); baseline and on-treatment (week 3) sTIL levels were available in 119 and 76 patients, respectively. Impacts of standardized gene expression signatures on pCR and invasive disease-free survival (iDFS) were estimated by logistic and Cox regression.

RESULTS

In all patients, ERBB2 [OR, 1.70; 95% confidence interval (CI), 1.08-2.67] and estrogen receptor (ER) signaling (OR, 1.72; 95% CI, 1.13-2.61) were favorable, whereas PTEN (OR, 0.57; 95% CI, 0.38-0.87) was unfavorable for pCR. After 60 months median follow-up, 13 invasive events occurred (P+T: n = 11, P+T+paclitaxel: n = 2), none following pCR. Gene signatures related to immune response (IR) and ER signaling were favorable for iDFS, all with similar HR about 0.43-0.55. These patterns were even more prominent in the neoadjuvant chemotherapy-free group, where additionally BRCAness signature was unfavorable (HR, 2.00; 95% CI, 1.04-3.84). IR signatures were strongly intercorrelated. sTILs (baseline/week 3/change) were not associated with pCR or iDFS, though baseline sTILs correlated positively with IR signatures.

CONCLUSIONS

Distinct gene signatures were associated with pCR versus iDFS in HER2+/HR- EBC. The potential role of IR in preventing recurrence suggests that patients with upregulated IR signatures could be candidates for de-escalation concepts in HER2+ EBC.

Perioperative ramucirumab in combination with FLOT versus FLOT alone for resectable esophagogastric adenocarcinoma (RAMSES/FLOT7) with high rate of signet cell component: Final results of the multicenter, randomized phase II/III trial of the German AIO and Italian GOIM

4042

Background: Periop. FLOT has become SOC for resectable, esophagogastric adenocarcinoma. However, patient’s outcome is still poor. This trial evaluates the addition of the VEGF-R2 inhibitor ramucirumab (RAM) to FLOT for resectable patients (pts). Methods: This is a prospective, international, randomized, investigator-initiated phase II/III trial. Pts with resectable, Her2-negative, adenocarcinoma of the stomach and GEJ type II and III (≥ cT2 or cN+) were enrolled. Pts were randomized to 4 pre-and post-operative cycles of FLOT (docetaxel 50 mg/m²; oxaliplatin 85 mg/m²; leucovorin 200 mg/m²; 5-FU 2600 mg/m², q2w) alone (Arm A) or the same regimen with RAM 8mg/kg q2w, followed by 16 cycles RAM (Arm B, FLOT-RAM). Important endpoints of phase II (exploratory) were major pathological (complete and nearly complete) response, centrally assessed acc. to Becker criteria, R0-resection rate, overall survival (OS), disease-free survival (DFS) and safety. GEJ type I tumors and pts requiring trans-thoracic esophagectomy were excluded for safety reasons during the conduct of the study. Results: In total, 152 pts were analyzed within the intention to treat population. Baseline characteristics were similar between arms (male, 70%; median age, 60y; cT3/T4, 82%; cN+, 77%; GEJ, 45%). The rate of cancers with signet-ring cell component was at 45%. The FLOT-RAM arm included more unfavorable pts with T4 (8% vs. 5%), impaired ECOG PS of 1 (32% vs. 20%), and concomitant disease (86% vs. 76%). 92% of pts with FLOT as well as with FLOT-RAM completed the 4 pre- cycles. R0-resection could be achieved in 82% of pts with FLOT and 96% of pts with FLOT-RAM (p = 0.0093). The rate of major path response was similar in both arms and was 29% for FLOT and 26% for FLOT-RAM. Median DFS was slightly improved in pts with FLOT-RAM (32 months vs. 21 months), while median OS was similar in both treatment arms (FLOT 45 months, FLOT-RAM 46 months). Surgical morbidity was observed in 32% of pts with FLOT and 41% of pts with FLOT-RAM. Mortality at 60 days after surgery was 4.1% with FLOT and 2.8% with FLOT-RAM. There were bit more G≥3 adverse events with FLOT-RAM (76% vs. 92%). Conclusions: In this phase II trial, the addition of ramucirumab to perioperative FLOT significantly improved R0-resection rates and slightly prolonged DFS without an impact on path response or overall survival. FLOT-RAM is feasible and safe, when type I tumors are excluded. Clinical trial information: NCT02661971.

Endocrine Therapy Response and 21-Gene Expression Assay for Therapy Guidance in HR+/HER2- Early Breast Cancer

PURPOSE

To our knowledge, WSG-ADAPT-HR+/HER2- (NCT01779206; n = 5,625 registered) is the first trial combining the 21-gene expression assay (recurrence score [RS]) and response to 3-week preoperative endocrine therapy (ET) to guide systemic therapy in early breast cancer.

MATERIALS AND METHODS

Baseline and postendocrine Ki67 (Ki67_post) were evaluated centrally. In the endocrine trial, all patients received exclusively ET: patients with pathologic regional lymph node status (pN) 0-1 (ie, 0-3 involved lymph nodes) entered control arm if RS ≤ 11 and experimental arm if RS12-25 with ET response (Ki67_post ≤ 10%). All other patients (including N0-1 RS12-25 without ET response) received dose-dense chemotherapy (CT) followed by ET in the CT trial. Primary end point of the endocrine trial was noninferiority of 5-year invasive disease-free survival (5y-iDFS) in experimental (v control) arm; secondary end points included distant DFS, overall survival, and translational research.

RESULTS

Intention-to-treat population comprised 2,290 patients (n = 1,422 experimental v n = 868 control): 26.3% versus 34.6% premenopausal and 27.4% versus 24.0% pN1. One-sided 95% lower confidence limit of the 5y-iDFS difference was -3.3%, establishing prespecified noninferiority (P = .05). 5y-iDFS was 92.6% (95% CI, 90.8 to 94.0) in experimental versus 93.9% (95% CI, 91.8 to 95.4) in control arm; 5-year distant DFS was 95.6% versus 96.3%, and 5-year overall survival 97.3% versus 98.0%, respectively. Differences were similar in age and nodal subgroups. In N0-1 RS12-25, outcome of ET responders (ET alone) was comparable with that of ET nonresponders (CT) for age > 50 years and superior for age ≤ 50 years. ET response was more likely with aromatase inhibitors (mostly postmenopausal) than with tamoxifen (mostly premenopausal): 78.1% versus 41.1% (P < .001). ET response was 78.8% in RS0-11, 62.2% in RS12-25, and 32.7% in RS > 25 (n = 4,203, P < .001).

CONCLUSION

WSG-ADAPT-HR+/HER2- demonstrates that guiding systemic treatment by both RS and ET response is feasible in clinical routine and spares CT in pre- and postmenopausal patients with ≤ 3 involved lymph nodes.

Immune Markers and Tumor-Related Processes Predict Neoadjuvant Therapy Response in the WSG-ADAPT HER2-Positive/Hormone Receptor-Positive Trial in Early Breast Cancer

Prognostic or predictive biomarkers in HER2-positive early breast cancer (EBC) may inform treatment optimization. The ADAPT HER2-positive/hormone receptor-positive phase II trial (NCT01779206) demonstrated pathological complete response (pCR) rates of ~40% following de-escalated treatment with 12 weeks neoadjuvant ado-trastuzumab emtansine (T-DM1) ± endocrine therapy. In this exploratory analysis, we evaluated potential early predictors of response to neoadjuvant therapy. The effects of PIK3CA mutations and immune (CD8 and PD-L1) and apoptotic markers (BCL2 and MCL1) on pCR rates were assessed, along with intrinsic BC subtypes. Immune response and pCR were lower in PIK3CA-mutated tumors compared with wildtype. Increased BCL2 at baseline in all patients and at Cycle 2 in the T-DM1 arms was associated with lower pCR. In the T-DM1 arms only, the HER2-enriched subtype was associated with increased pCR rate (54% vs. 28%). These findings support further prospective pCR-driven de-escalation studies in patients with HER2-positive EBC.

Prognostic impact of recurrence score, endocrine response and clinical-pathological factors in high-risk luminal breast cancer: Results from the WSG-ADAPT HR+/HER2- chemotherapy trial

504

Background: In HR+/HER2- N0-1 early BC, postmenopausal patients (pts) with RS™ > 25 and a substantial proportion of premenopausal pts seem to benefit from addition of adjuvant chemotherapy (CT) to endocrine therapy (ET). However, the magnitude of absolute benefit from this treatment intensification seems to depend on clinical-pathological and biological prognostic factors. For the first time, we present outcome from the CT part of the prospective phase III WSG-ADAPT HR+/HER- trial combining both static (RS in baseline core biopsy (CB) and dynamic (Ki67 response) biomarkers to optimize adjuvant therapy in luminal EBC. Methods: Pts with clinically high-risk HR+/HER2- EBC (cT2-4 OR clinically N+ OR G3 OR Ki67>15%) were initially treated by 3 (+/-1) weeks of standard ET (postmenopausal: mostly AI; premenopausal: TAM) before surgery or sequential CB. Pts with cN2-3 or G3/Ki67>40% were randomized directly to the CT trial. pN0-1 pts with RS0-11 OR RS12-25/ET-response (central Ki67postendocrine<10%) received ET alone; the remaining high-risk cohort was randomized to the CT trial: (neo)adjuvant dose-dense CT (4xPaclitaxelà4xEC q2w vs. 8xNab-Paclitaxel q1wà4xEC q2w) followed by ET. Primary endpoint is efficacy comparison of CT schedules for survival; secondary endpoints reported here involve impacts of key prognostic factors on survival. Kaplan-Meier and Cox proportional hazard models were used to estimate survival curves and hazard ratios. For this analysis, subgroups free of selection bias by RS/ET-response were defined. Results: 5625 pts were screened and 4621 (ITT) entered the trial. After 4.9y median follow-up, higher baseline and post-endocrine Ki-67 levels were associated with poorer iDFS (both p < 0.001). In the CT cohort (n = 2331), higher RS, nodal status, and tumor size were generally associated with poorer iDFS. However, iDFS differed between N1 and N0 status only among younger pts (<50 years). In pts with >4 positive LN (n = 390), lower RS was associated with improved iDFS (RS0-11 vs RS > 25: plog-rank= 0.016, 5y-iDFS 90% vs. 64%). In pts with RS > 25 (n = 965), low Ki67postendocrine, N0 status, and c/pT1 status were associated with improved iDFS. In particular, ET-responders had higher 5y-iDFS (84%) than ET-non-responders (77%; plog-rank= 0.040). Younger patients (<50 years old) with N0-1 RS 12-25/ ET-non-responders treated by CT had non-significantly poorer 5-year iDFS (89%) compared to those with ET-response treated by ET only (92%) (plog-rank= 0.249). Conclusion: First results from the prospective high risk cohort from a large prospective phase III ADAPT trial provide evidence for good prognosis in some pts with >4 positive LN and e.g. low RS. Moreover combination of lower post-endocrine Ki-67 and limited tumor burden may be a promising criterion for CT de-escalation strategies even in patients with high RS. Clinical trial information: NCT01779206.

De-escalated neoadjuvant pertuzumab+trastuzumab with or without paclitaxel weekly in HR-/HER2+ early breast cancer: ADAPT-HR-/HER2+ biomarker and survival results

503

Background: Optimal use of de-escalated, particularly chemotherapy(CT)-free, neoadjuvant regimens in HER2+ early breast cancer (EBC) is currently unclear as there are limited survival data so far. In ADAPT-HR-/HER2+, we previously showed an excellent pCR rate of 90% after 12-week neoadjuvant paclitaxel (Pac) +pertuzumab (P) +trastuzumab (T) and a substantial and clinically meaningful pCR rate of 34% after P+T alone in HR-/HER2+ EBC. Here, we present first survival data. Methods: The prospective multicenter WSG-ADAPT-HR-/HER2+ phase II-trial is part of the ADAPT-umbrella protocol. Patients with cT1-cT4c, cN0-3 HR-/HER2+ EBC (n = 134) were randomized to 4 cycles of P+T +/- pac d1,8,15 q3w. All tumors were HR-negative (ER and PR < 1%) and HER2-positive (central lab, i.e., 2+ FISH positive or 3+ by immunohistochemistry. Primary endpoint was pCR (ypT0/is/ypN0); omission of further CT was allowed in pts with pCR. Trial objective was to compare pCR in P+T+pac arm vs. early responders in P+T arm (defined as low cellularity and/or Ki67 decrease >30% after 3 weeks). The trial was stopped early due to the observed pCR superiority in the P+T+pac arm. Secondary endpoints included safety, 5-y (distant)-DFS, OS and translational research. Cox-regression analysis was applied. PAM50 subtype was assessed using the BC360 panel. Results: 134 patients were randomized to P+T (n = 92) or P+T+pac (n = 42). 60% of tumors were cT2-4, 42% clinically node-positive. After a median follow-up of 5 years, no significant differences between study arms were observed regarding DFS, dDFS, and OS; only 13 iDFS events (7 dDFS) were observed in the whole ITT population. pCR (vs. non-pCR) after the 12-week study treatment (irrespective of study arm) was strongly associated with improved iDFS (5y DFS 98.5% vs. 82%, HR = 0.14, 95% CI 0.03-0.64). Of the 69 patients with pCR, 39 (56.5%) received no further CT (P+T arm: n = 9, 29% vs. (P+T+pac arm n = 30, 79%); only 1 distant relapse (1.4%) was observed in these patients. In the CT-free P+T arm, no pCR was observed in patients with low HER2 expression (IHC 1+/2+ and FISH positive) and/or basal-like subtype by PAM50 (n = 17, 19%). In the total study population, low HER2 expression and/or no early response was strongly associated with worse dDFS (p =.029) and iDFS (p =.068). No new safety signals were observed. Conclusions: For the first time, we have shown both excellent pCR and survival in patients treated by de-escalated neoadjuvant CT+P+T irrespective of further CT use in a prospective multicenter study. Investigation of CT-free regimens may need to be focussed on selected patients only (e.g. with high HER2 expression/non-basal-like tumors). In ADAPT HR-/HER2+, early pCR after only 12 weeks of neoadjuvant P+T+pac was strongly associated with improved outcome and may thus serve as a predictive clinical marker for further treatment (de)-escalation. Clinical trial information: NCT01779206.

The PLATON pilot-study “Platform for analyzing targetable tumor mutations”: A PLATON network study

TPS6598

Background: PLATON Network is designed as a platform to improve personalized therapy based on genomic profiles in gastrointestinal cancer patients. PLATON’s study-design focuses on patient’s molecular profiling and will provide a network web application for interlinking PLATON investigators which integrates information of the participating centers, their patients, the molecular profiles and available clinical trials at PLATON`s study-sites. Methods: The PLATON Network is designed as a permanent open, multicenter, prospective, cohort study with biobanking, with a shared platform infrastructure for associated sub-studies. In a first approach the PLATON Network enrolls within its pilot-study 200 patients in Germany of both sexes and ages over 18 at 40 study sites (NCT04484636) with signed informed consent. All patients of the pilot-study are diagnosed with hepatocellular cancer (HCC), intra- and extrahepatic cholangiocellular carcinoma (CCA), gallbladder carcinoma (GBCA), pancreatic cancer (PDCA) or esophagogastric cancer (EC/GC). At the time of enrolment, patients are within their first-line therapy and no local curative therapy is available. Molecular profiling will be performed with the Foundation Medicine Assays FoundationOne CDx and FoundationOne Liquid CDx. Investigators may use the platform for searching clinical trials matching the individual molecular profile of their patients or may identify a patient, who may be eligible for a study or other treatment options available at the corresponding centers of the PLATON network. The interactive network web application will comprise a dashboard and a moderated chat room to interact for example in a virtual Molecular Tumor Board. The first patient was included on the 25th of November 2020. Up to 12th of February 2021, a total of 36 patients HCC (N = 1), CCA (N = 6), PDCA (N = 12), GBCA (N = 0) and EC/GC (N = 16) were enrolled at 11 study-sites and the results of 29 genetic analyses were completed. All cohorts of the pilot-study are open for recruitments up to a maximum of 40 individuals per diagnostic group. Clinical trial information: NCT04484636.

Early response by MR imaging and ultrasound as predictor of pathologic complete response to 12-week neoadjuvant therapy for different early breast cancer subtypes: Combined analysis from the WSG ADAPT subtrials

We evaluated the role of early response after 3 weeks of neoadjuvant treatment (NAT) assessed by ultrasound (US), magnetic resonance imaging (MRI) and Ki-67 dynamics for prediction of pathologic complete response (pCR) in different early breast cancer subtypes. Patients with HR+/HER2+, HR-/HER2- and HR-/HER2+ tumors enrolled into three neoadjuvant WSG ADAPT subtrials underwent US, MRI and Ki-67 assessment at diagnosis and after 3 weeks of NAT. Early response was defined as complete or partial response (US, MRI) and ≥30% proliferation decrease or <500 invasive tumor cells (Ki-67). Predictive values and area under the receiver operating characteristic (AUC) curves for prediction of pCR (ypT0/is ypN0) after 12-week NAT were calculated. Two hundred twenty-six had MRI and 401 US; 107 underwent both MRI and US. All three methods yielded a similar AUC in HR+/HER2+ (0.66-0.67) and HR-/HER2- tumors (0.53-0.63), while MRI and Ki-67 performed better than US in HR-/HER2+ tumors (0.83 and 0.79 vs 0.56). Adding MRI+/-Ki-67 increased AUC of US in HR-/HER2+ tumors to 0.64 to 0.75. MRI and Ki-67 demonstrated highest sensitivity in HR-/HER2- (0.8-1) and HR-/HER2+ tumors (1, both). Negative predictive value was similar for all methods in HR+/HER2+ (0.71-0.74) and HR-/HER2- tumors (0.85-1), while it was higher for MRI and Ki-67 compared to US in HR-/HER2+ subtype (1 vs 0.5). Early response assessed by US, MRI and Ki-67 is a strong predictor for pCR after 12-week NAT. Strength of pCR prediction varies according to tumor subtype. Adding MRI+/-Ki-67 to US did not improve pCR prediction in majority of our patients.

Magnetic resonance imaging and ultrasound for prediction of residual tumor size in early breast cancer within the ADAPT subtrials

Background

Prediction of histological tumor size by post-neoadjuvant therapy (NAT) ultrasound and magnetic resonance imaging (MRI) was evaluated in different breast cancer subtypes.

Methods

Imaging was performed after 12-week NAT in patients enrolled into three neoadjuvant WSG ADAPT subtrials. Imaging performance was analyzed for prediction of residual tumor measuring ≤10 mm and summarized using positive (PPV) and negative (NPV) predictive values.

Results

A total of 248 and 588 patients had MRI and ultrasound, respectively. Tumor size was over- or underestimated by < 10 mm in 4.4% and 21.8% of patients by MRI and in 10.2% and 15.8% by ultrasound. Overall, NPV (proportion of correctly predicted tumor size ≤10 mm) of MRI and ultrasound was 0.92 and 0.83; PPV (correctly predicted tumor size > 10 mm) was 0.52 and 0.61. MRI demonstrated a higher NPV and lower PPV than ultrasound in hormone receptor (HR)-positive/human epidermal growth factor receptor 2 (HER2)-positive and in HR−/HER2+ tumors. Both methods had a comparable NPV and PPV in HR−/HER2− tumors.

Conclusions

In HR+/HER2+ and HR−/HER2+ breast cancer, MRI is less likely than ultrasound to underestimate while ultrasound is associated with a lower risk to overestimate tumor size. These findings may help to select the most optimal imaging approach for planning surgery after NAT.

Trial registration

Clinicaltrials.gov, NCT01815242 (registered on March 21, 2013), NCT01817452 (registered on March 25, 2013), and NCT01779206 (registered on January 30, 2013).

Supplementary Information

The online version contains supplementary material available at 10.1186/s13058-021-01413-y.

Abstract GS4-03: Neoadjuvant nab-paclitaxel weekly versus dose-dense paclitaxel followed by dose-dense EC in high risk HR+/HER2- early BC by: Results from the neoadjuvant part of ADAPT HR+/HER2- trial

Background: Pathological complete response (pCR) is associated with improved outcome in patients with high-risk HR+/HER2- breast cancer (BC) but the use of (neo)adjuvant chemotherapy in early HR+/HER2- BC remains controversial. Oncotype DX / Recurrence Score (RS) and dynamic Ki67 response after short preoperative endocrine therapy are potentially predictive for pCR. Still, no prospective data are available so far to predict chemotherapy efficacy in this key patient group. Use of dose-dense chemotherapy is associated with improved outcome in meta-analysis, but its use in the neoadjuvant setting is less studied. Furthermore, use of nab-paclitaxel instead of solvent-based paclitaxel has shown promising results in some studies. Here, we present for the first time data from a randomized prospective trial comparing these risk-selection strategies according to RS and Ki67 decrease in high-risk HR+/HER2- BC. Methods: High-risk BC patients [cN0-1 with RS&gt;25 or (RS 12-25 AND (centrally measured) post-endocrine Ki67 &gt;10%] OR [cN2-3 status] OR [G3 AND Ki67&gt;40%] were randomized to (neo)adjuvant 4x paclitaxel175 q2w or 8xnab-paclitaxel 125 mg/m2q1w followed by 4x E90C600 q2w. pCR was defined as no invasive tumor in breast and lymph nodes. Results: 858 patients with available surgery data randomized to neoadjuvant Pac-EC (N=423) or nab-Pac-EC (N=435) were analyzed. Median age was 51 years; median RS was 30 (N=572); 34% had node-positive; 46% (locally) G3 tumors. Baseline characteristics were well balanced between study arms. Patients receiving nab-Pac-EC had higher pCR than those with Pac-EC (20.3% vs. 12.3%, p=.002); patients with RS&lt;25 (about 27%) had a lower pCR rate than those with RS&gt;25 (6.5% vs. 15.8%, p=.003). The association of RS with pCR appeared more pronounced in premenopausal women, but a test of interaction was not significant; RS was about 3 points higher (mean 32.9 vs. 29.8, p&lt;.001) in postmenopausal cases (p=.001). Clinical tumor stage cT2-4 was reported in 65%, with a lower pCR rate than in cT1 tumors (14% vs. 20%, p=.02). RS was moderately correlated (R=.45) with baseline Ki67. In multivariable analysis with tumor stage, RS, Ki67, menopausal status, and ER and PR positivity, higher RS and cT1 stage were favorable for pCR. Excluding RS, higher Ki67 and lower ER (as well as cT1) were favorable. In patients with RS&lt;25, there was no pCR with Pac-EC (0/72 pCR); pCR was almost 20% with RS&gt;25 and nab-Pac-EC. Further details and data including impacts of Ki67 dynamics and additional markers on pCR will be presented at the meeting. Conclusions: Use of neoadjuvant nab-paclitaxel instead of solvent-based paclitaxel appears promising within a short (16-weeks) dose-dense chemotherapy schedule in high-risk HR+/HER2- BC. For the first time, data from a large neoadjuvant randomized trial confirm RS could help to select patients for neoadjuvant chemotherapy in high-risk HR+/HER2- breast cancer (BC).

Citation Format: Sherko Kuemmel, Oleg Gluz, Ulrike Nitz, Michael Braun, Matthias Christgen, Kerstin Luedtke-Heckenkamp, Raquel von Schumann, Maren Darsow, Helmut Forstbauer, Jochem Potenberg, Eva-Maria Grischke, Bahriye Aktas, Claudia Schumacher, Ronald Kates, Monika Graeser, Rachel Wuerstlein, Christoph Uleer, Michael Hauptmann, Steve Shak, Rick Baehner, Hans Kreipe, Nadia Harbeck, West German Study Group. Neoadjuvant nab-paclitaxel weekly versus dose-dense paclitaxel followed by dose-dense EC in high risk HR+/HER2- early BC by: Results from the neoadjuvant part of ADAPT HR+/HER2- trial [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr GS4-03.

Randomized multicenter phase II/III study with adjuvant gemcitabine versus neoadjuvant/adjuvant FOLFIRINOX in resectable pancreatic cancer: The NEPAFOX trial

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Background: The outcome of pancreatic cancer remains poor. Few patients (pts) can be assigned to surgery and 80% of resected pts experience a relapse. Currently, adjuvant ctx is standard, but prognosis remains poor. FOLFIRINOX (FFX) is a SOC in metastatic and meanwhile in the adjuvant setting and may represent a valuable neoadjuvant option in resectable and borderline resectable stages. We initiated the NEPAFOX– trial in Germany to explore the efficacy of perioperative FFX. Methods: This is a multicenter randomized phase II/III trial. Recruitment of the trial was stopped after 40 patients (pts) due to poor accrual. Pts with resectable or borderline resectable adenocarcinoma of the pancreas without metastases were eligible. Eligible pts were randomized to (arm A) upfront surgery followed by adjuvant gemcitabine (1000 mg/m2) for 6 months or (arm B) perioperative FFX (irinotecan 180 mg/m2, oxaliplatin 85 mg/m2, 5-FU 400mg/m² bolus, 5-FU 2400 mg/m², sodium folinate 400 mg/m2) 4-6 cycles (8-12 weeks) pre and further 4-6 cycles post surgery. The primary endpoint is OS. Secondary endpoints include PFS, perioperative morbidity, mortality, and others. Results: 40 pts (42.5% female) were randomized over 3 years (05.03.2015 FPI - 23.03.2018 LPI), 21 in arm A, 19 in arm B. Age range was 46-84y, median age 64y.Before randomization, 76.2% of the pts in Arm A and 78.9% in Arm B were classified as primarily resectable the remaining pts as borderline resectable. Patients received in median 3 cycles in Arm A (range: 0-6) and 6 in Arm B (range: 1-12). Surgery was performed in 18 pts (85.7%) in Arm A and 11 (57.9%) in Arm B. Reasons for not conducting surgery were for Arm A patient´s wish (1 pt) and inoperability (2 pts), for Arm B early progressive disease (4 pts), death (1 pt), pneumonia (1 pt), and toxicities (1 pt). 13 (Arm A) and 5 (Arm B) pts had a R0-Resection. Perioperative morbidity occurred in 72.2% of operated pts in Arm A and 45.5% in Arm B. Median OS was 25.68 months in Arm A (6 events of death) and 10.03 months in Arm B (14 events) with HR 0.366 and p = 0.0337. Median PFS was 9.8 months in Arm A (12 events) and 6.64 months in Arm B (16 events) with HR 0.722 and p = 0.4099. Conclusions: Due to low pt numbers, the analyses for primary and secondary endpoints are not robust and only descriptive. Median OS for Gemcitabine- arm was in the line with literature data and better than for FFX, but pt/event numbers are too for conclusion. Only 11 out of 19 FFX pts underwent surgery, only 9 pts had pancreatic resection, indicating that pts should be extremely good selected before starting a neoadjuvant approach. According to CT or MRI pts of arm B were not more advanced regarding tumor staging. Nevertheless, there were no safety issues in the FFX arm regarding surgical complications, so neoadjuvant/ perioperative treatment approach seems to be feasible, subjected to the small number of pts in the study. Clinical trial information: NCT02172976.

De-escalated chemotherapy versus endocrine therapy plus pertuzumab+ trastuzumab for HR+/HER2+ early breast cancer (BC): First efficacy results from the neoadjuvant WSG-TP-II study

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Background: HR+/HER2+ breast cancer (BC) is a distinct entity associated with better prognosis compared to HR-/HER2+ BC. However, combination of chemotherapy (CT) with (dual) anti-HER2 blockade is standard in HER2+ early BC (EBC), irrespective of HR-status. Despite of some promising data on combination of endocrine therapy (ET) with dual anti-HER2 blockade in EBC and metastatic HR+/HER2+ BC, no prospective comparison of neoadjuvant CT vs. ET + dual HER2-blockade has yet been performed. Methods: In the prospective WSG TP-II phase II-trial (NCT03272477; Sponsor: Palleos GmbH, Wiesbaden, Germany), 207 patients (pts) (257 screened; 40 centers) with centrally confirmed HR+/HER2+ EBC were randomized to 12 weeks of standard ET (n=100) vs. paclitaxel 80 mg/m2 weekly (n=107) +trastuzumab+pertuzumab q3w for all pts. Primary endpoint was pCR (ypT0/is/ypN0). Secondary endpoints include safety, disease-free and overall survival, translational research, and quality of life (QoL). Omission of further CT was allowed in all pts with pCR; dual HER2-blockade was administered in the adjuvant setting in all pts. Results: Baseline characteristics were well balanced between the arms. Median age was 53 years; 58% had cT2-4, 28% had cN+; 43% had G3 tumors. pCR data were available in 198 pts (ET: n=96; Pac: n=102). pCR was observed in 24% (95% CI: 16-34%) with ET+T+P vs. 57% (95% CI:47-67%) with Pac+T+P (OR 0.24, 95% CI: 0-0.46, p<0.001). In multivariable logistic regression analysis and corresponding sensitivity analysis (bootstrap/subsample inclusion frequencies and lasso regression) including study arm, BMI, menopausal, cT, and cN status, histological grade, HER2-status, Ki67, ER, PR as continuous variables, only study arm and HER2 3+ status were significantly associated with pCR. Neoadjuvant treatment was well tolerated in both study arms and completed per protocol in 93/92 (ET+P+T/Pac+P+T) patients. Only 9/13 SAEs (ET+P+T/Pac+P+T) were reported during neoadjuvant therapy. PAM50 and QoL analysis are ongoing. Conclusions: WSG TP-II is the first randomized prospective trial comparing two neoadjuvant de-escalation treatments in HR+/HER2+ EBC. The excellent pCR rate of 57% after only 12 weeks of Pac+P+T was clearly superior to the still promising 24% pCR rate in pts treated by ET+P+T. In both arms, treatment efficacy was most pronounced in HER2 3+ tumors. Survival results need to be awaited before definite recommendations for a de-escalated regimen in HR+/HER2+ EBC can be made. Clinical trial information: 2016-005157-21 .

Perioperative ramucirumab in combination with FLOT versus FLOT alone for resectable esophagogastric adenocarcinoma (RAMSES/FLOT7): Results of the phase II-portion—A multicenter, randomized phase II/III trial of the German AIO and Italian GOIM

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Background: Periop. FLOT has become SOC for resectable, esophagogastric adenocarcinoma. However, patient’s outcome is still poor. This trial evaluates the addition of the VEGF-R2 inhibitor ramucirumab (RAM) to FLOT for resectable patients (pts). Methods: This is a prospective, international, randomized, investigator-initiated phase II/III trial. Pts with resectable, Her2-negative, adenocarcinoma of the stomach and GEJ (≥ cT2 or cN+) were enrolled. Pts were randomized to 4 pre-and post-operative cycles of FLOT (docetaxel 50 mg/m²; oxaliplatin 85 mg/m²; leucovorin 200 mg/m²; 5-FU 2600 mg/m², q2w) alone (Arm A) or the same regimen with RAM 8mg/kg q2w, followed by 16 cycles RAM (Arm B, FLOT-RAM). Important endpoints of phase II (exploratory) were major pathological (complete and nearly complete) response, centrally assessed acc. to Becker criteria, R0-resection rate, and safety. GEJ type I tumors and pts requiring trans-thoracic esophagectomy were excluded for safety reasons during the conduct of the study. Results: In total, 180 pts were randomized. Baseline characteristics were similar between arms (male, 73%; median age, 60y; cT3/T4, 83%; cN+, 78%; GEJ, 54%; signet-ring cells, 40%). However, the FLOT-RAM arm included more unfavorable pts with T4 (9% vs. 4%), Siewert type I tumors (18% vs. 13%), impaired ECOG PS of 1 (34% vs. 20%), and concomitant disease (87% vs. 79%). 91% of pts with FLOT and 92% with FLOT-RAM completed the 4 pre- cycles. R0-resection (in the full set) could be achieved in 83% of pts with FLOT and 97% of pts with FLOT-RAM (p = 0.0049). The rate of major path response was similar in both arms and was 30% for FLOT and 27% for FLOT-RAM. Surgical morbidity was observed in 37% of pts with FLOT and 44% of pts with FLOT-RAM. Mortality was 2.5% with FLOT and 5.9% with FLOT-RAM including GEJ type I tumors and dropped to 2.9% in both arms after excluding type I tumors per amendment. There was bit more G≥3 adverse events with FLOT-RAM (78% vs. 89%). Conclusions: In this phase II trial, the addition of ramucirumab to perioperative FLOT significantly improved R0-resection rates without an impact on path response, mainly because more patients could proceed to operation. The FLOT-RAM is safe, when type I tumors are excluded. Clinical trial information: NCT02661971 .

Abstract P2-16-05: Efficacy of response- and toxicity-guided neoadjuvant chemotherapy in elderly early breast cancer patients: Results of WSG ADAPT elderly sub-trial

Introduction: More than 1/3 of early breast cancers (EBC) are diagnosed in women ≥ 70 years. Although polychemotherapy has been shown to be more effective than monochemotherapy also in these patients, only limited prospective data on efficacy of neoadjuvant therapy are available so far. Here, we present results of the prospective ADAPT Elderly sub-study from the WSG ADAPT umbrella protocol.

Methods: Patients ≥70 years with high-risk HR+/HER2- EBC (i.e. Recurrence Score (RS)&gt;25 or RS 12-25 with post-endocrine Ki67 of &gt;10% or ≥cN2) or HR-/HER2- EBC were treated by 2 cycles of liposomal doxorubicin (Myocet® 60 mg/m2)/cyclophosphamide 600 mg/m2 (MC). In case of clinical response by ultrasound (&gt;50% reduction in the sum of two largest diameters) and no AE grade 3-4, patients received an additional 2 cycles MC, otherwise they were switched to 6 cycles of paclitaxel (80 mg/m2) weekly. A sample size of n=150 was planned to demonstrate non-inferiority of the response- and toxicity-guided regimen vs. 4 cycles MC in responding patients (25% assumed pCR). The study was stopped early due to slow recruitment.

Results: Between 09/2014 and 10/2015, 83 EBC patients from 31 centers were registered; 78 started with therapy (40 HR+/HER2-; 38 HR-/HER2-). Median age was 74 years. 64% had G3 tumors, 66% cT24, and 34% cN+. Median Ki67 was 40%. 75/78 pts underwent stratification after 2 cycles; 1 pt withdrew consent: 45(61%) were responders with no severe toxicities, 29 (39%) non-responders or suffered toxicity grade 3-4. Surgical information is available in 72 patients (43 responder/no toxicity, 29 no response/toxicity groups respectively). pCR was observed in 7 patients in the responder/no toxicity group (i.e. 16% irrespective of HR status) and in n=3 patients in the no response/toxicity group (10%). Updated efficacy and safety data will be presented at the meeting.

Discussion: In one of the largest neoadjuvant chemotherapy-studies specifically for elderly pts with HER2- EBC, we observed a lower than expected pCR rate after 4 cycles of anthracycline-containing neoadjuvant chemotherapy. Taxane-based standard chemotherapy may thus be preferable in this population. Nevertheless, neoadjuvant chemotherapy seems feasible in elderly pts with high-risk HER2- EBC and should further be explored in the context of potential pCR-based (de)escalation strategies.

Citation Format: Sherko Kuemmel, Oleg Gluz, Matthias Christgen, Jochem Potenberg, John Hackmann, Raquel von Schumann, Monika Graeser, Marina Mangold, Rachel Wuerstlein, Ronald Kates, Hans H. Kreipe, Ulrike Nitz, Nadia Harbeck, West German Study Group. Efficacy of response- and toxicity-guided neoadjuvant chemotherapy in elderly early breast cancer patients: Results of WSG ADAPT elderly sub-trial [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P2-16-05.

Abstract P4-10-05: Predictive value of HER2 expression, early response and tumor infiltrating lymphocytes (TILs) on efficacy of de-escalated pertuzumab+trastuzumab in the neoadjuvant WSG-ADAPT-HER2+/HR- trial

Purpose: Only limited data are available on predictive markers for use of chemotherapy-free, anti-HER2 combinations in HER2-positive early breast cancer (eBC), in particular within the molecularly distinct HER2+/HR- subgroup.

Background: In the ADAPT HER2+/HR- trial, a promising pCR of about 43-45% was found in patients treated by 4 cycles of pertuzumab and trastuzumab with either defined early response (low tumor cellularity or relative Ki-67 decrease ≥30%) or indeterminate early response (e.g. no visible tumor by ultrasound), compared to under 10% in early non-responders. In addition to early response, HER2 protein expression and stromal TIL (s-TIL) dynamics after one cycle of therapy are promising tools for identification of patients with high likelihood of pathological complete response (pCR) after therapy with double anti-HER2 blockade (e.g. by lapatinib+trastuzumab) or T-DM1.

Methods: Patients with cT1-cT4c, cN0-3 early HER2+/HR- BC (n=134) were treated with 4 cycles of P+T +/- paclitaxel d1,8,15 q3w. Primary endpoint of the study was pCR (ypT0/is, ypN0). All tumors were HR-negative (ER and PR&lt;1%) and locally HER2 positive, i.e., 2+ with positive FISH or 3+ by immunohistochemistry (IHC). HR and HER2 status were confirmed by central pathology prior to randomization.

Tumors were classified as “HER2-low” if HER2-1+ or HER2-2+ by either local or central IHC assessment, otherwise “HER2-high”. s-TILs were measured semi-quantitively according to current international consensus in triplicate at baseline and on-treatment (at cycle 2); the median of the three measurements was taken to define the quantities TIL-0 and TIL-3, respectively. “Lymphocyte-dominant subtype” at baseline and cycle 2 were defined as TIL-0≥40% and TIL-3≥40%, respectively.

The present analysis characterizes the predictive impact of early response HER2 protein expression, and s-TILs on pCR under dual anti-HER2 therapy for the first time within a prospective neoadjuvant trial specific to the HER2+/HR- BC subtype.

Results: As previously reported, pCR was 34.4% without chemotherapy and 90.5% with chemotherapy. TIL-0 and TIL-3 were available in n=119/134 and n=103/134 patients, respectively. TIL-0 and TIL-3 were not significantly associated with pCR in the whole cohort or within the T+P arm, either modeled as a continuous variable or in terms of binary variables representing lymphocyte-dominant subtype or defined by the respective population medians.

HER2-high expression was found in 87% of patients. In the T+P arm, pCR was much higher in HER2-high than HER2-low patients (40.3% vs. 0%, p=.003).

In the T+P arm, 24 and 38 of 92 patients were classified as non- and responders, unclassified early response was observed in 30 of 92 patients. pCR in these groups were 8.3% vs. 44.7% vs. 42.9% respectively. Higher baseline TILs were positively associated with early response.

Clinically meaningful pCR of 49% after only 4 cycles of chemotherapy-free P+T was seen in those patients with early response after one cycle of therapy and HER2-high classification, compared to 11.8% in the HER2-high/non-responder group).

Conclusions: At present, a combination of baseline high HER2 expression with low cellularity after one cycle of neoadjuvant therapy – rather than s-TIL determination (at baseline or in response to therapy) – appears to be a simple and feasible tool for identification of candidates for de-escalated treatment in HER2+/HR- disease. Further research on high-precision determination of HER2-high expression (by immunohistochemistry vs. mRNA-based tools) is strongly needed for optimal patient selection for future chemotherapy de-escalation trials.

Citation Format: Oleg Gluz, Cornelia Kolberg-Liedtke, Claudia Biehl, Matthias Christgen, Sherko Kuemmel, Eva-Maria Grischke, Doris Augustin, Michael Braun, Jochem Potenberg, Monika Graeser, Ronald Kates, Rachel Wuerstlein, Friedrich Feuerhake, Ulrike Nitz, Hans Kreipe, Nadia Harbeck, West German Study Group. Predictive value of HER2 expression, early response and tumor infiltrating lymphocytes (TILs) on efficacy of de-escalated pertuzumab+trastuzumab in the neoadjuvant WSG-ADAPT-HER2+/HR- trial [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P4-10-05.

Sorafenib plus topotecan versus placebo plus topotecan for platinum-resistant ovarian cancer (TRIAS): a multicentre, randomised, double-blind, placebo-controlled, phase 2 trial

BACKGROUND

Antiangiogenic therapy has known activity in ovarian cancer. The investigator-initiated randomised phase 2 TRIAS trial assessed the multi-kinase inhibitor sorafenib combined with topotecan and continued as maintenance therapy for platinum-resistant or platinum-refractory ovarian cancer.

METHODS

We did a multicentre, double-blind, placebo-controlled, randomised, phase 2 trial at 20 sites in Germany. Patients (≥18 years) with platinum-resistant ovarian cancer previously treated with two or fewer chemotherapy lines for recurrent disease were stratified (first vs later relapse) in block sizes of four and randomly assigned (1:1) using a web-generated response system to topotecan (1·25 mg/m² on days 1-5) plus either oral sorafenib 400 mg or placebo twice daily on days 6-15, repeated every 21 days for six cycles, followed by daily maintenance sorafenib or placebo for up to 1 year in patients without progression. Investigators and patients were masked to allocation of sorafenib or placebo; topotecan treatment was open label. The primary endpoint was investigator-assessed progression-free survival, analysed in all patients who received at least one dose of study drug. This completed trial is registered with ClinicalTrials.gov, number NCT01047891.

FINDINGS

Between Jan 18, 2010, and Sept 19, 2013, 185 patients were enrolled, 174 of whom were randomly assigned: 85 to sorafenib and 89 to placebo. Two patients in the sorafenib group had serious adverse events before treatment and were excluded from analyses. 83 patients in the sorafenib group and 89 in the placebo group started treatment. Progression-free survival was significantly improved with sorafenib versus placebo (hazard ratio 0·60, 95% CI 0·43-0·83; p=0·0018). Median progression-free survival was 6·7 months (95% CI 5·8-7·6) with sorafenib versus 4·4 months (3·7-5·0) with placebo. The most common grade 3-4 adverse events were leucopenia (57 [69%] of 83 patients in the sorafenib group vs 47 [53%] of 89 in the placebo group), neutropenia (46 [55%] vs 48 [54%]), and thrombocytopenia (23 [28%] vs 20 [22%]). Serious adverse events occurred in 49 (59%) of 83 sorafenib-treated patients and 45 (51%) of 89 placebo-treated patients. Of these, events were fatal in four patients (5%) in the sorafenib group (dyspnoea and poor general condition, septic shock, ascites and dyspnoea, and sigma perforation) and seven (8%) in the placebo group (pulmonary embolism in two patients, disease progression in two patients, and one case each of sepsis with fever, pleural effusion, and tumour cachexia). Sorafenib was associated with increased incidences of grade 3 hand-foot skin reaction (three [13%] vs 0 patients) and grade 2 alopecia (24 [29%] vs 12 [13%]).

INTERPRETATION

Sorafenib, when given orally in combination with topotecan and continued as maintenance therapy, showed a statistically and clinically significant improvement in progression-free survival in women with platinum-resistant ovarian cancer. These encouraging results support the crucial role of antiangiogenesis as the treatment backbone in combination with chemotherapy, making this approach attractive for further assessment with other targeted strategies.

FUNDING

Bayer, Amgen, and GlaxoSmithKline.

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.

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.

Panitumumab in platinum-sensitive epithelial ovarian cancer patients with KRAS wild-type: The PROVE-study, a phase II randomized multicenter study of the North-Eastern German Society of Gynaecologic Oncology

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Background: For ovarian cancer (OC) patients with platinum-sensitive recurrence the addition of new biologic agents to chemotherapy may improve survival. Panitumumab is a fully human monoclonal antibody specific to the epidermal growth factor receptor (EGFR). The purpose of this trial was to investigate the therapeutic efficacy of panitumumab in the combination with carboplatin-based chemotherapy in relation to the respective standard combination in patients with a KRAS wildtype with platinum-sensitive recurrent ovarian cancer (NCT01388621). Methods: Major eligibility criteria were pretreated platinum-sensitive epithelial ovarian/ fallopian/ peritoneal cancer and no more than 2 prior treatments for this disease. Only patients with measurable disease or elevated CA125 and with KRAS wild type were eligible. Patients were treated with Carboplatin AUC4/Gemcitabine 1000 mg/m² or Carboplatin AUC5/PLD 40 mg/m² and randomized to panitumumab 6 mg/kg day 1 and day 15, every 3 or 4 weeks. Tumor assessment was performed at baseline and at every third cycle according to CT-scan and CA-125 criteria. Results: In this multi-institutional phase II trial 102 patients were randomized and 96 enrolled for the final analysis. Progression-free survival in the intention-to-treat population (N=96) was 9.5 vs. 10.7 months (HR 0.829, 95%CI of 8.5-11.6 months vs 8.5-13.1 months) for the experimental vs. standard arm, p=0.45. Data of overall survival are not jet evaluable. The most common treatment related grade 3+ toxicities included hematologic toxicity (54%), skin reactions (18%) and gastrointestinal events (16%). Conclusions: The addition of panitumumab to platinum-based chemotherapy for recurrent ovarian cancer does not influence efficacy and progression-free survival in platinum sensitive patients, while no new additional toxicity aspects for panitumumab were evaluated. Clinical trial information: NCT01388621.

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.

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.

Mapisal Versus Urea Cream as Prophylaxis for Capecitabine-Associated Hand-Foot Syndrome: A Randomized Phase III Trial of the AIO Quality of Life Working Group

Purpose

Hand-foot syndrome (HFS) is a frequently occurring adverse event associated with anticancer drugs. This study compares a newly introduced ointment containing several antioxidants and exhibiting high radical protection factor, which has been available on the German market since 2011, with urea cream for prevention of HFS in patients treated with capecitabine.

Patients and Methods

Patients with GI tumors or breast cancer treated with capecitabine were included in this randomized phase III study. The primary end point was prevention of HFS of any grade within 6 weeks of treatment as indicated by a standardized patient diary. The study had 80% power to show a 20% reduction of the incidence of HFS with the new ointment. Secondary end points included time to development of HFS greater than grade 1, evaluation of capecitabine dose intensity, and quality of life analyses.

Results

A total of 152 patients were evaluable. In total, 47 of 152 patients experienced HFS (30.9%), 39.5% with the new ointment and 22.4% in the urea arm (stratified odds ratio, 2.37; P = .02). Time to HFS greater than grade 1 was comparable, but time to any-grade HFS was significantly longer in the urea group (P = .03). Capecitabine dose intensity, time under study, and percentage of days with correct administration of study medication were identical, as were adverse events except for HFS. Skin-related quality of life was significantly worse in the group treated with the new ointment at the end of study treatment.

Conclusion

This trial demonstrated that 10% urea cream was superior to the new ointment at preventing HFS over the first 6 weeks of treatment with capecitabine.

A randomized phase 2 study comparing EC or CMF versus nab-paclitaxel plus capecitabine as adjuvant chemotherapy for nonfrail elderly patients with moderate to high-risk early breast cancer (ICE II-GBG 52)

BACKGROUND

Although greater than 40% of breast cancers occur in patients aged ≥65 years, these individuals are frequently undertreated. Taxane-based adjuvant chemotherapy is considered the treatment of choice but to the authors' knowledge has only limited evidence in elderly patients.

METHODS

Patients aged ≥65 years with a Charlson comorbidity index ≤2 and pT1/2 pN0/1 disease and either human epidermal growth factor receptor 2 (HER2)-positive, hormone receptor-negative, grade 3 (according to Common Terminology Criteria for Adverse Events [version 3.0]), high uPA/PAI-1 or any stage pT3/4 pN2/3 breast cancer were randomized to receive 4 cycles of adjuvant epirubicin and cyclophosphamide (EC) (epirubicin at a dose of 90 mg/m(2) and cyclophosphamide at a dose of 600 mg/m(2) intravenously [iv] on day 1 every 3 22 days) or 6 cycles of cyclophosphamide, methotrexate, and 5-fluorouracil (CMF) (cyclophosphamide at a dose of 500 mg/m(2), methotrexate at a dose of 40 mg/m(2), and 5-fluorouracil at a dose of 600 mg/m(2) iv on days 1 plus 8 every 29 days) versus 6 cycles of nab-paclitaxel and capecitabine (nPX) (nab-paclitaxel at a dose of 100 mg/m(2) iv on days 1, 8, and 15 every 21 days with 1 week of rest every 6 weeks plus capecitabine at a dose of 2000 mg/m(2) orally on days 1-14 every 21 days). Primary endpoints were treatment discontinuations and overall frequency of adverse events.

RESULTS

Thirteen of 198 patients (6.6%) discontinued EC/CMF and 69 of 193 patients (35.8%) discontinued nPX (P<.001) with 1 and 5 deaths observed during treatment, respectively. Grade 3 to 5 adverse events were more frequent among patients treated with EC/CMF (90.9%) than among those treated with nPX (64.8%) (P<.001), with hematological toxicities being more frequent with EC/CMF (88.4% vs 22.3%; P<.001), but nonhematological toxicities (hand-foot syndrome, diarrhea, mucositis, fatigue, sensory neuropathy, thromboembolisms, and metabolic disorders) being more frequent with nPX (58.5% vs 18.7%; P<.001). None of the geriatric scores (Charlson comorbidity index, Vulnerable Elders Survey [VES-13], Instrumental Activities of Daily Living [IADL], and G8) independently predicted grade 3 to 5 toxic events or treatment discontinuations. No differences in survival between the treatment groups were observed after 22.8 months.

CONCLUSIONS

Compared with EC/CMF, treatment with nPX led to more treatment discontinuations and nonhematological toxicities in elderly patients with moderate or high-risk breast cancer.

Abstract P4-15-01: Distinct early proliferation response to neoadjuvant anti-HER2 antibody drug conjugate +/- endocrine therapy in early breast cancer in the WSG ADAPT HER2+/HR+ trial

Background: HER2+, hormone receptor-positive (HR+) breast cancer is a distinct subtype associated with good prognosis but poor response to standard chemotherapy + anti-HER2 (single or dual blockade). Substantial overtreatment by poly-chemotherapy combined with anti-HER2 therapy is suspected in this subtype. Yet, the efficacy of combining endocrine therapy (ET) with anti-HER2 therapy or novel antibody drug conjugates like T DM1 without systemic chemotherapy remains unclear.

Methods: ADAPT HER2+/HR+ is a phase II, randomized, neoadjuvant, 3-arm trial (12 weeks) in patients with cT1c-cT3, cN0/+ HER2+, ER+ and/or PR+ early BC. Arm A: T-DM1 (3.6 mg/kg) alone; Arm B: T DM1 + ET (premenopausal: tamoxifen, postmenopausal: AI); Arm C: trastuzumab + ET. Postoperative chemotherapy is recommended together with completion of one year of trastuzumab. Initial and serial core biopsies were obtained prior to therapy and after 3 weeks. First translational analysis of the trial run-in phase (n=130) focuses on dynamics of HER2, Ki67, ER and PR.

Results: 162 tumors, HR+ and HER2+ by local pathology, were screened; n=130 were HR+ and HER2+ by central pathology and randomized at 40 trial sites in Germany between 11/2012 and 03/2014 (Arm A/B/C: 37/49/44).

Median age was 49 years; 60% were cT2-3, 32% cN+, 75% central G3; median baseline Ki67 was 30%; 49 patients were treated by TAM and 44 postmenopausal patients by AI in ET containing arms.

Three-week core biopsies were available in 117 patients (arm A/B/C: n=33/43/41), n=99 with invasive tumor tissue (61/76 (80%) in T-DM1 containing arms and 38/41(93%) in trastuzumab + ET arm). Three-week Ki67 could only be analyzed in n=73 (53% of patients in T-DM1-containing arms, 81% in the T+ET arm) due to a lacking amount of cells for counting (&lt;500).

Median fractional decrease in proliferation (Ki67) after 3 weeks of therapy was 40% in the T-DM1 + ET arm (B) as compared to 14% and 25% in the T-DM1 (A) and T+ET (C) arms, respectively. Among postmenopausal patients, the contrast (52% (B) vs. 0% (A) and 28% (B)) was significant. Mean PR expression change (absolute, measured in %) was -15 in the B Arm vs. 7 and -7 in the A and C arms, respectively (p=0.04) – particularly in postmenopausal women ( 25 vs. +13 and -10, respectively, p=0.04). Baseline ER expression was positively associated with early proliferation response (fractional Ki67 decrease), e.g., by logistic regression using 30% decrease as response criterion. Data on the impact of gene mutations and further molecular markers on proliferation response will be available for presentation at the meeting.

Conclusions: In the unique neoadjuvant ADAPT HER2+/HR+ trial, the combination of T-DM1 with ET (particularly AI) seems to be associated with a strong early proliferation response and PR expression drop in anti-HER2 antibody (drug conjugate) +/- ET, without systemic pre-operative chemotherapy. Interim analysis is scheduled after 130 completely treated patients. The high percentage of non-invasive tissue biopsied after 3 weeks in the T-DM1 arms is intriguing, as it would be consistent with higher pathological complete response rates.

Citation Format: Oleg Gluz, Ulrike Nitz, Kuemmel Sherko, Kraemer Stefan, Michael Braun, Claudia Schumacher, Bahriye Aktas, Helmut Forstbauer, Toralf Reimer, Peter Fasching, Jochem Potenberg, Daniel Hofmann, Ronald E Kates, Rachel Wuerstlein, Matthias Christgen, Hans H Kreipe, Nadia Harbeck. Distinct early proliferation response to neoadjuvant anti-HER2 antibody drug conjugate +/- endocrine therapy in early breast cancer in the WSG ADAPT HER2+/HR+ trial [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P4-15-01.

Survival after neoadjuvant chemotherapy with or without bevacizumab or everolimus for HER2-negative primary breast cancer (GBG 44-GeparQuinto)†

BACKGROUND

The GeparQuinto study showed that adding bevacizumab to 24 weeks of anthracycline-taxane-based neoadjuvant chemotherapy increases pathological complete response (pCR) rates overall and specifically in patients with triple-negative breast cancer (TNBC). No difference in pCR rate was observed for adding everolimus to paclitaxel in nonearly responding patients. Here, we present disease-free (DFS) and overall survival (OS) analyses.

PATIENTS AND METHODS

Patients (n = 1948) with HER2-negative tumors of a median tumor size of 4 cm were randomly assigned to neoadjuvant treatment with epirubicin/cyclophosphamide followed by docetaxel (EC-T) with or without eight infusions of bevacizumab every 3 weeks before surgery. Patients without clinical response to EC ± Bevacizumab were randomized to 12 weekly cycles paclitaxel with or without everolimus 5 mg/day. To detect a hazard ratio (HR) of 0.75 (α = 0.05, β = 0.8) 379 events had to be observed in the bevacizumab arms.

RESULTS

With a median follow-up of 3.8 years, 3-year DFS was 80.8% and 3-year OS was 89.7%. Outcome was not different for patients receiving bevacizumab (HR 1.03; P = 0.784 for DFS and HR 0.974; P = 0.842 for OS) compared with patients receiving chemotherapy alone. Patients with TNBC similarly showed no improvement in DFS (HR = 0.99; P = 0.941) and OS (HR = 1.02; P = 0.891) when treated with bevacizumab. No other predefined subgroup (HR+/HER2-; locally advanced (cT4 or cN3) or not; cT1-3 or cT4; pCR or not) showed a significant benefit. No difference in DFS (HR 0.997; P = 0.987) and OS (HR 1.11; P = 0.658) was observed for nonearly responding patients receiving paclitaxel with or without everolimus overall as well as in subgroups.

CONCLUSIONS

Long-term results, in opposite to the results of pCR, do not support the neoadjuvant use of bevacizumab in addition to an anthracycline-taxane-based chemotherapy or everolimus in addition to paclitaxel for nonearly responding patients.

CLINICAL TRIAL NUMBER

NCT 00567554, www.clinicaltrials.gov.

First evaluation of the Joint Clinical Registries of the Coordinating Tumor Center of Berlin

In the present study, we report the first analysis of the clinical management [corrected] of patients with primary ovarian cancer following the summarized data of the Joint Clinical Registries of the Coordinating Tumor Center of Berlin (Dachverband Tumorzentrum Berlin e.V.). All data were summarized for the period of 2005 to 2008 regarding age, histopathology, time of surgical intervention, follow-up and survival, based on 1124 provided data sets of patients with suspected ovarian tumours. We identified 946 patients with a diagnosis of primary ovarian cancer, mostly of advanced T3 tumour stage (63.7%), FIGO III and IV stage (40.6%) or grade II and III (91%) histology. The median age at time of diagnosis was 61 years (range 15 to 94 years). Most patients (n=414, 69.8%) underwent cytoreductive surgery within one month of diagnosis. The median follow-up period was 26 months; 241 patients died in the analyzed period. The calculated 3-year survival rate was 63.3%, although the median overall survival has not yet been reached. We detected positive correlation of tumour stage (p<0.001) and of FIGO stage (p<0.001) with survival, and these were evaluated as being prognostically significant. The implementation of institutional based clinical registries as part of the modern clinical management of patients with ovarian cancer is feasible and well accepted inside the gynaecological departments of Berlin.

Enhancement and inhibition of benzo[a]pyrene-induced SOS function in E. coli by synthetic antioxidants

8 antioxidants were tested in the SOS chromotest for induction of SOS function and for modulation of benzo[a]pyrene-induced SOS function. None of the antioxidants leads to increased beta-galactosidase activity by itself. Butylated hydroxytoluene at concentrations between 10(-5) M and 3 X 10(-4) M enhances benzo[a]pyrene-induced SOS function at benzo[a]pyrene concentrations between 10(-6) M and 3 X 10(-5) M. Butylated hydroxyanisole, ethoxyquin, propyl gallate and octyl gallate also slightly enhance benzo[a]pyrene-induced SOS function at concentrations up to 3 X 10(-4) M though to a lesser degree than butylated hydroxytoluene. Dodecyl gallate, vitamin C and alpha-tocopherol do not increase benzo[a]pyrene action. In concentrations exceeding 3 X 10(-4) M all synthetic antioxidants tested but not vitamin C and alpha-tocopherol decrease beta-galactosidase activity both in the absence and, more extensively, in the presence of benzo[a]pyrene. Preliminary data suggest that the apparent suppression of benzo[a]pyrene-induced SOS function is not due to an effect on the formation of benzo[a]pyrene metabolites by the metabolizing system used.

Modulation of benzo[a]pyrene-induced morphological transformation of Syrian hamster embryo cells by butylated hydroxytoluene and butylated hydroxyanisole

The Syrian hamster embryo cell transformation assay has been used to investigate the effect of two synthetic antioxidants on morphological transformation induced by the initiator benzo[a]pyrene (BP). A two-stage protocol was employed with an initiation phase of 2 days and a subsequent promotion phase of 5 days. When 10 microM butylated hydroxytoluene (BHT) were present in the promotion phase instead of the solvent the transformation frequency at 0.1 micrograms BP/ml increased from 0.27% to 0.55%; at 100 microM of BHT the transformation frequency was 0.77%. Butylated hydroxyanisole (BHA) also enhanced the percentage of transformed colonies from 0.40% (10 microM) to 0.49% (100 microM), respectively. No significant initiating activity was detected for both antioxidants when tested in the initiation phase instead of BP; when the antioxidants were applied simultaneously with BP (1 microgram/ml) during the initiation phase the transformation frequency was decreased from 0.64% to 0.15% (100 microM BHT) and to 0.17% (100 microM BHA), respectively. These results show that the dual action of phenolic antioxidants on chemical carcinogenesis, which depends on the administration schedule, can be imitated in an in vitro test system. In addition to their anti-initiation effect, BHT and BHA, while devoid of intrinsic initiator potency, exert a moderate promotional activity on hamster embryo cell cultures. Their ability to enhance tumorigenesis by various carcinogens in vivo is likely to be at least partially related to such promotion-like effects on cell growth and morphology.