Management of Trastuzumab Deruxtecan-related nausea and vomiting in real-world practice

Background

Nausea and vomiting are common side effects of Trastuzumab Deruxtecan (T-DXd), but guidelines for optimal management were not initially available. This retrospective single-center study aimed at evaluating the efficacy of two antiemetic regimens in patients receiving T-DXd.

Methods

Data from metastatic breast cancer patients receiving T-DXd were collected. Two groups were defined: patients treated with 5-HT3 receptor antagonists (RA) ± dexamethasone (5-HT3-group) and patients treated with a fixed oral combination of netupitant (NK1RA) and palonosetron ± dexamethasone (NK1 group). Physicians preferentially offered the NK1 regimen to patients at higher risk of nausea and vomiting based on internal recommendations. Only nausea and vomiting during cycles 1 and 2 were considered. Comparisons of nausea and vomiting by the antiemetic prophylaxis group were assessed using chi-square.

Results

A total of 53 patients were included in the analysis. At cycle 1, 72% and 28% of patients received the 5-HT3 and NK1 prophylaxis, respectively. Overall, 58% reported nausea, with no differences between groups (58% vs. 60%; p = 0.832), but with a trend for lower grade in the NK1 group (33.3% G1; 26.7% G2) compared to the 5-HT3 group (23.7% G1; 31.6% G2; 2.6% G3). Vomiting was reported by 21% and 0% of patients in the 5-HT3 and the NK1 group, respectively (p = 0.054). Among the 15 patients in the 5-HT3 group with nausea at cycle 1 who escalated to NK1 at cycle 2, nausea decreased from 100% to 53% (p = 0.022) and vomiting decreased from 47% to 13% (p = 0.046).

Conclusions

The NK1 regimen improved vomiting control at cycle 1 and, when introduced at cycle 2, significantly improved both nausea and vomiting. The biased NK1 selection for higher-risk patients may have dampened the differences between groups at cycle 1. These findings support enhanced control of T-DXd-related nausea and vomiting with NK1RA.

Impact of pembrolizumab versus chemotherapy on health-related quality of life in patients with metastatic triple-negative breast cancer: results from the phase 3 randomised KEYNOTE-119 study

BACKGROUND

In KEYNOTE-119 (ClinicalTrials.gov, NCT02555657), overall survival (primary end-point) was similar between pembrolizumab and chemotherapy in patients with previously treated metastatic triple-negative breast cancer (TNBC), although the pembrolizumab treatment effect increased with tumour PD-L1 expression. We report results of prespecified health-related quality of life (HRQoL) analyses from KEYNOTE-119.

METHODS

Eligible patients were randomised 1:1 to pembrolizumab 200 mg Q3W intravenously for up to 35 cycles or treatment of physician's choice per local/country guidelines. Prespecified exploratory end-points were the change from baseline in HRQoL (EORTC QLQ-C30, QLQ-BR23) and to characterise utilities (EQ-5D-3L). Time to deterioration (TTD) was the time from start of treatment to first onset of a ≥10-point worsening from baseline.

RESULTS

HRQoL analyses included 187 patients with tumour PD-L1 combined positive score (CPS) ≥10. Changes from baseline at 6 weeks (primary analysis time point) were directionally better with pembrolizumab versus chemotherapy for QLQ-C30 GHS/QoL (between-group difference in least-squares mean scores of 4.21 [95% CI, -1.38 to 9.80]), QLQ-C30 functional scales (physical, role, cognitive, social), QLQ-C30 symptom scales/items (fatigue, nausea/vomiting, dyspnoea, appetite loss), and QLQ-BR23 symptom scales/items (systemic therapy side-effects, upset by hair loss). Median TTD was directionally longer for pembrolizumab versus chemotherapy for QLQ-C30 QHS/QoL (4.3 versus 1.7 months), QLQ-C30 nausea/vomiting (7.7 versus 4.8 months), and QLQ-BR23 systemic therapy side-effects (6.1 versus 3.4 months). Minimal treatment differences were observed for other HRQoL end-points.

CONCLUSIONS

HRQoL results were consistent with clinical outcomes and appeared to be driven by results for patients with tumour PD-L1 CPS ≥10.

Spatial predictors of immunotherapy response in triple-negative breast cancer

Immune checkpoint blockade (ICB) benefits some patients with triple-negative breast cancer, but what distinguishes responders from non-responders is unclear1. Because ICB targets cell-cell interactions2, we investigated the impact of multicellular spatial organization on response, and explored how ICB remodels the tumour microenvironment. We show that cell phenotype, activation state and spatial location are intimately linked, influence ICB effect and differ in sensitive versus resistant tumours early on-treatment. We used imaging mass cytometry3 to profile the in situ expression of 43 proteins in tumours from patients in a randomized trial of neoadjuvant ICB, sampled at three timepoints (baseline, n = 243; early on-treatment, n = 207; post-treatment, n = 210). Multivariate modelling showed that the fractions of proliferating CD8+TCF1+T cells and MHCII+ cancer cells were dominant predictors of response, followed by cancer-immune interactions with B cells and granzyme B+ T cells. On-treatment, responsive tumours contained abundant granzyme B+ T cells, whereas resistant tumours were characterized by CD15+ cancer cells. Response was best predicted by combining tissue features before and on-treatment, pointing to a role for early biopsies in guiding adaptive therapy. Our findings show that multicellular spatial organization is a major determinant of ICB effect and suggest that its systematic enumeration in situ could help realize precision immuno-oncology.

Modulation of the Estrogen/erbB2 Receptors Cross-talk by CDK4/6 Inhibition Triggers Sustained Senescence in Estrogen Receptor- and ErbB2-positive Breast Cancer

PURPOSE

The interplay between estrogen receptor (ER) and erbB tyrosine-kinase receptors (RTK) impacts growth and progression of ER-positive (ER+)/HER2-positive (HER2+) breast cancer and generates mitogenic signals converging onto the Cyclin-D1/CDK4/6 complex. We probed this cross-talk combining endocrine-therapy (fulvestrant), dual HER2-blockade (trastuzumab and pertuzumab), and CDK4/6-inhibition (palbociclib; PFHPert).

EXPERIMENTAL DESIGN

Cytotoxic drug effects, interactions, and pharmacodynamics were studied after 72 hours of treatment and over 6 more days of culture after drug wash-out in three ER+/HER2+, two HER2low, and two ER-negative (ER-)/HER2+ breast cancer cell lines. We assessed gene-expression dynamic and association with Ki67 downregulation in 28 patients with ER+/HER2+ breast cancer treated with neoadjuvant PFHPert in NA-PHER2 trial (NCT02530424).

RESULTS

In vitro, palbociclib and/or fulvestrant induced a functional activation of RTKs signalling. PFHPert had additive or synergistic antiproliferative activity, interfered with resistance mechanisms linked to the RTKs/Akt/MTORC1 axis and induced sustained senescence. Unexpected synergism was found in HER2low cells. In patients, Ki67 downregulation at week 2 and surgery were significantly associated to upregulation of senescence-related genes (P = 7.7E-4 and P = 1.8E-4, respectively). Activation of MTORC1 pathway was associated with high Ki67 at surgery (P = 0.019).

CONCLUSIONS

Resistance associated with the combination of drugs targeting ER and HER2 can be bypassed by cotargeting Rb, enhancing transition from quiescence to sustained senescence. MTORC1 pathway activation is a potential mechanism of escape and RTKs functional activation may be an alternative pathway for survival also in ER+/HER2low tumor. PFHPert combination is an effective chemotherapy-free regimen for ER+/HER2+ breast cancer, and the mechanistic elucidation of sensitivity/resistance patterns may provide insights for further treatment refinement.

Dermatological and Dermoscopic Baselines in BRCA Mutation Carriers

Breast cancer-associated genes 1 and 2 (BRCA1 and BRCA2) are tumor suppressor genes encoding a large protein that is involved in many essential biological processes. BRCA mutated patients show an increased risk to develop several malignancies, including cutaneous malignancies, although inconsistently across multiple studies. We carried out an observational study on the main dermatological and dermoscopic aspects in a population of patients with BRCA 1/2 mutations, to identify the main clinical and dermoscopical features in this class of patients. A total of 52 patients with BRCA mutations were included in the current analysis. Clinical, dermoscopical, and pathological data were obtained during the dermatologic visits. Out of the entire cohort, 67.3% of patients showed brown hairs and 63.5% of patients showed brown eyes, with phototype III as the most frequent phototype (69.2%). A total of 2.017 melanocytic lesions in all patients were analyzed; specifically, 40 patients (76.9%) showed a total number of nevi > 10, while regarding the main observed dermoscopic features, a prevalence of reticular pattern in 63% of cases was observed, followed by a mixed pattern in 19.2% of cases. Regarding the cutaneous examination, eruptive angiomas (eCAs) were the main dermatologic manifestations in 46.2% of patients. Out of 52 patients and during a follow-up of 24 months one patient developed an in situ melanoma. Interestingly, none of the patients with eCAs showed a TN > 10, highlighting an inverse correlation. To date, there is insufficient evidence to warrant increased surveillance in patients with BRCA mutations or with a positive family history for BRCA mutations, in the absence of standard cutaneous risk factors. Further studies with larger samples of patients are needed to better investigate dermatological and dermatoscopic features in BRCA mutation carriers.

Pathologic complete response (pCR) to neoadjuvant treatment with or without atezolizumab in triple negative, early high-risk and locally advanced breast cancer. NeoTRIP Michelangelo randomized study

BACKGROUND

High-risk triple negative breast cancers (TNBC) are characterized by poor prognosis, rapid progression to metastatic stage and onset of resistance to chemotherapy, thus representing an area in need of new therapeutic approaches. PD-L1 expression is an adaptive mechanism of tumour resistance to tumour infiltrating lymphocytes, which in turn are needed for response to chemotherapy. Overall, available data support the concept that blockade of PD-L1/PD-1 check-point may improve efficacy of classical chemotherapy.

PATIENTS AND METHODS

Two-hundred-eighty patients with TNBC were enrolled in this multicentre study (NCT002620280) and randomized to neoadjuvant carboplatin AUC 2 and nab-paclitaxel 125 mg/m² iv on days 1 and 8, without (N = 142) or with (N = 138) atezolizumab 1200 mg iv on day 1. Both regimens were given q3 weeks for 8 cycles before surgery and 4 cycles of an adjuvant anthracycline regimen. The primary aim of the study is to compare event-free survival, an important secondary aim was the rate of pathological complete remission (pCR defined as absence of invasive cells in breast and lymph nodes). The primary population for all efficacy endpoints is the intention-to-treat population.

RESULTS

The intention-to-treat analysis revealed that pCR rate after treatment with atezolizumab (48.6%) did not reach statistical significance compared to no atezolizumab [44.4%: odds ratio (OR) 1.18; 95% CI 0.74-1.89; P = 0.48]. Treatment-related adverse events were similar with either regimen except for a significantly higher overall incidence of serious adverse events and liver transaminases abnormalities with atezolizumab.

CONCLUSIONS

The addition of atezolizumab to nab-paclitaxel and carboplatin did not significantly increase the rate of pCR in women with TNBC. In multivariate analysis the presence of PD-L1 expression was the most significant factor influencing rate of pCR (OR 2.08). Continuing follow up for the event-free survival is ongoing, and molecular studies are under way.

Abstract P1-04-02: Immune milieu associated with PD-L1 status in TNBC is dependent on time of biomarker assessment and treatment received: A secondary analysis of the NeoTRIPaPDL1 trial

Background - In the NeoTRIPaPDL1 phase III trial, triple-negative breast cancer (TNBC) patients were randomized to receive nab-paclitaxel/carboplatin for 8 cycles (CT arm) with or without atezolizumab (CT/A arm). We previously reported that the majority of patients (65%) with PD-L1- at baseline converted to PD-L1+ (the majority with IC2/IC3) after the first cycle of treatment in the atezolizumab arm. Here we studied treatment associated changes in the molecular tumour features and immune microenvironment by PD-L1 expression. Methods – A total of 158 (56.4%) of patients enrolled in the NeoTRIPaPDL1 trial (76 and 82 from CT/A and CT arm, respectively) were included in this analysis by satisfying the following criteria: i) availability of a paired core biopsy at baseline and at day 1 of the second treatment cycle (D1C2); ii) evaluation of stromal TILs (sTILs) and staining for PD-L1 (Ventana SP142); iii) successful RNA-seq gene expression profiling. PD-L1 groups were defined as IC0/IC1 (<5% PD-L1low) vs IC2/IC3 (>=5% PD-L1high). Presence of different immune cell populations was quantified by gene expression profile deconvolution using ConsensusTME R package. Cancer hallmark gene set collection and custom signature activation status were estimated in each sample using singscore R package. Differences in score distribution were evaluated by 2-sided t-test. Results At baseline, both sTILs and immune cell signatures were upregulated in PD-L1high compared to PD-L1low tumours (p<0.001). No significant differences were found between the two treatment arms in the PD-L1high subpopulation. In the PD-L1low cases, both sTILs and immune related signatures were slightly downregulated in the CT/A arm (p<0.05), suggesting a modest unbalance among treatment arms with CT arm being slightly more inflamed than CT/A arm.At D1C2, PD-L1high tumours in the CT arm systematically had high sTILs (median=70%, range=30-90%), while PD-L1low tumours receiving CT/A had low sTILs in a significant proportion of cases (median=30%, range=0-90%; p<0.001). Similarly, at D1C2 several gene expression-estimated immune cell populations and immune-related signatures were upregulated in the CT arm compared to CT/A arm in PD-L1high tumours, with the weakest association observed for M2 macrophages (p=0.058). No tumour-related signatures were differentially expressed among the two treatment arms within groups with PD-L1high, suggesting that different treatment. modulate PD-L1 by engaging a different immune mileau instead of modulating tumor related features.Considering PD-L1low groups at D1C2, in the CT arm 21 tumors had >30% sTILs (n=21/69, 30.4%), while in the CT/A arm only 2 had sTILs >30% (2/27, 7.4%) (p<0.001). Analysis of gene expression data identified IFN-related signatures as the most upregulated in the CT compared to CT/A arm in PD-L1low cases at D1C2 (p<0.05). Conclusions Integrated dynamic analysis of PD-L1 expression and gene expression data highlighted significant treatment-specific changes of the immune landscape according to PD-L1 expression, when this biomarker is assessed during treatment. This indicates that the immune milieu associated with PD-L1 status is strongly dependent on the time of assessment in relationship to treatment received. Such observation may explain why in the NeoTRIP trial, baseline PD-L1 but not on-treatment PD-L1 was predictive of pCR in CT/A arm. In addition, our findings could have implications related to the use of PD-L1 as a predictive biomarker in pre-treated patients, especially when assessed early on during treatment.

Citation Format: Maurizio Callari, Chiun-Sheng Huang, Daniel Egle, Begoña Bermejo, Claudio Zamagni, Matteo Dugo, Marc Thill, Antonio Anton, Marco Barreca, Stefania Russo, Eva Maria Ciruelos, Richard Greil, Stefania Zambelli, Balázs Gyorffy, Chanel Smart, Olivia Biasi, Pinuccia Valagussa, Giuseppe Viale, Luca Gianni, Giampaolo Bianchini. Immune milieu associated with PD-L1 status in TNBC is dependent on time of biomarker assessment and treatment received: A secondary analysis of the NeoTRIPaPDL1 trial [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P1-04-02.

Abstract GS1-00: Single-cell spatial analysis by imaging mass cytometry and immunotherapy response in triple-negative breast cancer (TNBC) in the NeoTRIPaPDL1 trial

Background Immunecheckpoint inhibitors are effective in early and advanced TNBC, however only aminority of patients benefit making precision immune-oncology a major unmetneed. Imaging mass cytometry (IMC) enables high dimensional tissue imaging atsubcellular resolution for assessment of TNBC ecosystems, providing informationon cell type composition, functional status, and spatial organisation. Methods InNeoTRIP patients with TNBC were randomized to eight cycles ofnab-paclitaxel/carbo (CT) with/without atezolizumab (CTA). Forty-four proteinsspanning cancer cells and the tumor microenvironment (TME) were assessed onpre-treatment biopsies (n=243/280; 86.8% evaluable after QC). FFPE samples werelabelled with antibodies conjugated to isotopically pure rare earth metalreporters and profiled at one micron resolution by IMC. For each sample, wehave generated three high dimensional images that encompass the tumor,tumor-stroma interface and adjacent stroma. We investigated the association ofprotein expression assessed separately for epithelial and TME cells, cellphenotypes, and spatial architectures with PD-L1 status (Ventana SP142),stromal TILs, TNBC types and pathological complete response (pCR). 237 patients(84.6%) have both IMC and RNA-seq available allowing for comparison with genesignatures derived from HALLMARK,ConsensusTME immune cell types, and Nanostring. Results Across243 samples we identify just over one million single cells. By supervised clustering,we defined 37 robust cell phenotypes. PD-L1-positive tumors, high stromal TILsand TNBC type were characterized by extreme heterogeneity and unique cell-type andspatial TME composition. Severalbiomarkers demonstrated a significant test for interaction. Considering proteinexpression, GATA3 and CD20 on TME, HLA-DR in epithelial cells and Ki67 assessedboth in epithelial and TME, had a significant test for interaction (p <0.05). For all these biomarkers, high expression (above median) was associatedwith an increase of pCR of >10% in favour of atezolizumab, whereas lowerexpression group demonstrated a similar pCR rate among arms.Two cellphenotypes, PD-L1+IDO+ antigen presenting cells (APCs) and CD56+ neuroendocrine(NE) epithelial cells, had a significant test for interaction. Higherexpression of these biomarkers was associated with higher likelihood of pCR in CTAarm, but not in CT arm. For example, PD-L1+IDO+APCs in the CTA arm wereassociated with pCR proportions of 64.6% and 24.6% for above- and below-mediangroups respectively (OR4.5 [2.01-10.1], p<0.001).Mostof these tests of interaction retained significance after adjustment by PD-L1status and stromal TILs. Notably, none among 61 gene-expression basedimmune-related pathways and 7 proliferation-related signatures demonstrated a significant test ofinteraction. Resultsof systematic multi-tiered image analysis at the levels of cell-cellinteractions and recurrent higher order multicellular complexes defining TNBC ecosystemsidentified by graph-based methods will be presented at the meeting. Conclusions Imaging mass cytometry provides a morecomprehensive overview of TNBC heterogeneity at a single-cell level withspatial resolution. Bulk protein or gene expression might deliver limitedpredictive information because it does not consider the cell compartment ofexpression. Precise cell phenotyping highlights the predictive role ofPD-L1+IDO+APCs and CD56+NE epithelial cells. Overall, we demonstrated that IMCis feasible in a large, randomized trial and provides independent predictiveinformation on immune checkpoint inhibitors benefit to PD-L1, TILs and gene-expressionprofiles.

Citation Format: Giampaolo Bianchini, Xiao Qian Wang, Esther Danenberg, Chiun-Sheng Huang, Daniel Egle, Maurizio Callari, Begoña Bermejo, Claudio Zamagni, Marc Thill, Anton Anton, Matteo Dugo, Stefania Zambelli, Stefania Russo, Eva Maria Ciruelos, Richard Greil, Vladimir Semiglazov, Marco Colleoni, Catherine Kelly, Gabriella Mariani, Lucia Del Mastro, Balázs Győrffy, Olivia Biasi, Pinuccia Valagussa, Giuseppe Viale, Luca Gianni, H Raza Ali. Single-cell spatial analysis by imaging mass cytometry and immunotherapy response in triple-negative breast cancer (TNBC) in the NeoTRIPaPDL1 trial [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr GS1-00.

Effects of neoadjuvant trastuzumab, pertuzumab and palbociclib on Ki67 in HER2 and ER-positive breast cancer

The crosstalk between estrogen and HER2 receptors and cell-cycle regulation sustains resistance to endocrine therapy of HER2- and hormone receptor-positive breast cancer. We earlier reported that women with HER2 and ER-positive breast cancer receiving neoadjuvant dual HER2-block and palbociclib in the NA-PHER2 trial had Ki67 decrease and 27% pathological complete responses (pCR). We extended NA-PHER2 to Cohort B using dual HER2-block and palbociclib without fulvestrant and report here Ki67 drops at week-2 (mean change −25.7), at surgery (after 16 weeks, mean change −9.5), high objective response (88.5%) and pCR (19.2%). In Cohort C [Ki67 > 20% and HER2_low (IHC 1+/2+ without gene amplification)], women also received fulvestrant, had dramatic Ki67 drop at week 2 (−29.5) persisting at surgery (−19.3), and objective responses in 78.3%. In view of the favorable tolerability and of the efficacy-predictive value of Ki67 drop at week-2, the chemotherapy-free approach of NA-PHER2 deserves further investigation in HER2 and ER-positive breast cancer. The trial is registered with ClinicalTrials.gov, number NCT02530424.

ER and immune-related signatures define benefit to palbociclib, trastuzumab, pertuzumab +/- fulvestrant in ER+/HER2+ breast cancer patients in the NA-PHER2 trial

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Background: In the NA-PHER2 study we assessed the association between biological pathways with pathological complete response (pCR) and Ki67 down-regulation Methods: Patients with centrally confirmed ER+ ( > 10%) HER2+ breast cancer (BC) were treated in two independent, non-randomized cohorts with neoadjuvant trastuzumab, pertuzumab, palbocilib with (Fulv, n = 30) or without (NoFulv, n = 28) fulvestrant (+/-LHRH analogues). We assessed RNA-seq on core-biopsies obtained pre-treatment [n = 53/58 (91.4%)], at day 14 [n = 49/58 (84.5%)], and on residual disease at surgery [n = 42/45 (93.3%)]. We investigated biomarker dynamics and association with pCR or Ki67 down-regulation (centrally evaluated) at day 14 and at surgery. In the overall population and in each cohort, we primarily assessed three pre-defined biomarkers (ER-metagene [from OncotypeDX], a CD8-metagene and ERBB2 expression), and secondarily we explored a pre-defined list of genesets. Continuous and categorical (median cut-point) variables were evaluated. Results: In the biomarker population, pCR rate was 22.5% (28.6% and 16.0% in Fulv and NoFulv cohorts). At baseline, continuous CD8-metagene (OR 1.85 [1.12-3.06], p = 0.016) and ER-metagene (OR 0.56 [0.34-0.90], p = 0.016) associated with higher and lower pCR rate, respectively. High ERBB2 (above median) was marginally associated with pCR (OR 3.83 [0.90-16.3], p = 0.068). Only ER- and CD8-metagenes retained significance in multivariate analysis and were similarly predictive in both cohorts. Combining categorical variables, the groups with high-CD8/low-ER and low-CD8/high-ER had 61.5% and 0% pCR rate respectively, whereas low-CD8/low-ER and high-CD8/high-ER had similar 15% pCR (p = 0.001). The association was significant in both cohorts (p = 0.019 Fulv; p = 0.028 NoFulv). Dynamic assessment of the same biomarkers at day 14 did not improve prediction. Higher ER-metagene at baseline, but not CD8 and ERBB2, was associated with robust down-regulation of Ki67 at day 14 (Ki67 < 2.7%, complete cell cycle arrest) only in Fulv cohort (p = 0.016). ER-metagene also associated with retained Ki67 down-regulation (Ki67 < 10%) at surgery (p = 0.002). Alternative ER- and immune-related signatures provided very similar results. The comprehensive landscape of complex molecular dynamics and exploratory association with outcome will be presented. Conclusions: In ER+/HER2+ BC, low expression of ER-related and high expression of immune-related genes identified patients with very high likelihood of achieving pCR with a chemo-free regimen. In the fulvestrant cohort, the group with high ER-metagene, despite a lower pCR rate, had higher Ki67 down-regulation at day 14, which has been associated with long-term benefit in luminal tumors. These findings provide a potential tool for tailored de-escalation strategies.

Pembrolizumab versus investigator-choice chemotherapy for metastatic triple-negative breast cancer (KEYNOTE-119): a randomised, open-label, phase 3 trial

BACKGROUND

Pembrolizumab showed durable antitumour activity and manageable safety in metastatic triple-negative breast cancer in the single-arm KEYNOTE-012 and KEYNOTE-086 trials. In this study, we compared pembrolizumab with chemotherapy for second-line or third-line treatment of patients with metastatic triple-negative breast cancer.

METHODS

KEYNOTE-119 was a randomised, open-label, phase 3 trial done at 150 medical centres (academic medical centres, community cancer centres, and community hospitals) in 31 countries. Patients aged 18 years or older, with centrally confirmed metastatic triple-negative breast cancer, Eastern Cooperative Oncology Group performance status of 0 or 1, who had received one or two previous systemic treatments for metastatic disease, had progression on their most recent therapy, and had previous treatment with an anthracycline or taxane were eligible. Patients were randomly assigned (1:1) using a block method (block size of four) and an interactive voice-response system with integrated web-response to receive intravenous pembrolizumab 200 mg once every 3 weeks for 35 cycles (pembrolizumab group), or to single-drug chemotherapy per investigator's choice of capecitabine, eribulin, gemcitabine, or vinorelbine (60% enrolment cap for each; chemotherapy group). Randomisation was stratified by PD-L1 tumour status (positive [combined positive score (CPS) ≥1] vs negative [CPS <1]) and history of previous neoadjuvant or adjuvant treatment versus de-novo metastatic disease at initial diagnosis. Primary endpoints were overall survival in participants with a PD-L1 combined positive score (CPS) of 10 or more, those with a CPS of 1 or more, and all participants; superiority of pembrolizumab versus chemotherapy was tested in all participants only if shown in those with a CPS of one or more. The primary endpoint was analysed in the intention-to-treat population; safety was analysed in the all-subjects-as-treated population. This Article describes the final analysis of the trial, which is now completed. This trial is registered with ClinicalTrials.gov, number NCT02555657.

FINDINGS

From Nov 25, 2015, to April 11, 2017, 1098 participants were assessed for eligibility and 622 (57%) were randomly assigned to receive either pembrolizumab (312 [50%]) or chemotherapy (310 [50%]). Median study follow-up was 31·4 months (IQR 27·8-34·4) for the pembrolizumab group and 31·5 months (27·8-34·6) for the chemotherapy group. Median overall survival in patients with a PD-L1 CPS of 10 or more was 12·7 months (95% CI 9·9-16·3) for the pembrolizumab group and 11·6 months (8·3-13·7) for the chemotherapy group (hazard ratio [HR] 0·78 [95% CI 0·57-1·06]; log-rank p=0·057). In participants with a CPS of 1 or more, median overall survival was 10·7 months (9·3-12·5) for the pembrolizumab group and 10·2 months (7·9-12·6) for the chemotherapy group (HR 0·86 [95% CI 0·69-1·06]; log-rank p=0·073). In the overall population, median overall survival was 9·9 months (95% CI 8·3-11·4) for the pembrolizumab group and 10·8 months (9·1-12·6) for the chemotherapy group (HR 0·97 [95% CI 0·82-1·15]). The most common grade 3-4 treatment-related adverse events were anaemia (three [1%] patients in the pembrolizumab group vs ten [3%] in the chemotherapy group), decreased white blood cells (one [<1%] vs 14 [5%]), decreased neutrophil count (one [<1%] vs 29 [10%]), and neutropenia (0 vs 39 [13%]). 61 (20%) patients in the pembrolizumab group and 58 (20%) patients in the chemotherapy group had serious adverse events. Three (<1%) of 601 participants had treatment-related adverse events that led to death (one [<1%] in the pembrolizumab group due to circulatory collapse; two [1%] in the chemotherapy group, one [<1%] due to pancytopenia and sepsis and one [<1%] haemothorax).

INTERPRETATION

Pembrolizumab did not significantly improve overall survival in patients with previously treated metastatic triple-negative breast cancer versus chemotherapy. These findings might inform future research of pembrolizumab monotherapy for selected subpopulations of patients, specifically those with PD-L1-enriched tumours, and inform a combinatorial approach for the treatment of patients with metastatic triple-negative breast cancer.

FUNDING

Merck Sharp & Dohme.

Abstract PS12-01: Pembrolizumab versus chemotherapy for previously treated metastatic triple-negative breast cancer (KEYNOTE-119): Efficacy in patients with lung or liver metastases

Background: KEYNOTE-119 (NCT02555657) is a randomized, open-label phase 3 study of pembrolizumab (pembro) monotherapy vs single-agent chemotherapy (chemo) in patients with previously treated metastatic triple-negative breast cancer (mTNBC). The results showed directionally favorable improvement in overall survival (OS) with pembro compared to chemo in patients with PD-L1−positive tumors, although statistical superiority was not demonstrated. The pembro treatment effect increased with PD-L1 enrichment, as measured by the combined positive score (CPS). Since treatment outcomes may vary by location of metastasis, we performed a retrospective, exploratory analysis to evaluate the efficacy of pembro vs chemo among patients with lung or liver metastasis at baseline enrolled in KEYNOTE-119.

Methods: Patients with centrally confirmed TNBC, 1-2 prior systemic treatments for metastatic disease, documented progression on most recent therapy and prior treatment with an anthracycline and/or taxane were randomized 1:1 to pembro 200 mg Q3W or single-agent chemo per investigator’s choice of capecitabine, eribulin, gemcitabine, or vinorelbine (60% enrollment cap for each). Patients were stratified by PD-L1 status (CPS &lt;1 vs ≥1) and history of prior neoadjuvant/adjuvant treatment vs de novo metastatic disease at initial diagnosis. Primary study end points were OS in patients with PD-L1 CPS ≥10, patients with CPS ≥1, and all patients.

Results: Overall, 622 patients were randomized in KEYNOTE-119 (pembro, n=312; chemo, n=310); median follow-up was 31 months at the April 11, 2019 data cutoff date. At baseline, 403 (65%) patients had lung metastasis and 173 (28%) had liver metastasis. Pembro did not improve OS vs chemo in patients with lung or liver metastases in the ITT population, although the HRs decreased as tumor PD-L1 expression increased, with the greatest benefit observed in patients with PD-L1 CPS ≥20 tumors (Table). Similar trends were observed for progression-free survival, objective response rate, and duration of response. In both treatment groups, presence of liver metastases at baseline was associated with shorter OS as compared to absence of liver metastases at baseline; this trend was not observed for lung metastases. Results should be interpreted with caution due to modest patient sample size in some subgroups.

Conclusion: Among patients with previously treated mTNBC who had lung or liver metastases for whom prognosis is typically poor, pembro monotherapy showed a benefit vs single-agent chemo in patients with increasing PD-L1 tumor enrichment. These findings are consistent with the results from the global study population.

Table. Analysis of Overall SurvivalITTCPS ≥1CPS ≥10CPS ≥20NMedian, mo (95% CI)HR (95% CI)NMedian, mo (95% CI)HR (95% CI)NMedian, mo (95% CI)HR (95% CI)NMedian, mo (95% CI)HR (95% CI)Patients With Lung MetastasesPembro2009.8 (7.4-11.7)0.99 (0.80-1.23)12710.6 (8.1-12.5)0.85 (0.65-1.10)5612.8 (9.3-17.2)0.80 (0.53-1.18)3117.0 (11.7-27.1)0.55 (0.32-0.95)Chemo20311.4 (8.7-13.1)13110.4 (7.2-12.7)6311.9 (7.3-14.9)3413.0 (7.2-15.8)Patients Without Lung MetastasesPembro11210.3 (8.3-13.6)0.92 (0.69-1.23)7610.8 (8.9-15.7)0.89 (0.63-1.26)4012.1 (8.6-16.4)0.79 (0.47-1.31)2612.8 (7.8-23.0)0.63 (0.32-1.24)Chemo10710.2 (7.2-12.7)719.9 (7.0-13.5)3511.3 (7.0-15.7)1810.5 (5.2-15.7)Patients With Liver MetastasesPembro876.5 (4.7-9.3)1.04 (0.76-1.43)577.7 (4.2-9.9)1.02 (0.69-1.51)2410.3 (6.2-16.4)0.78 (0.44-1.39)1310.7 (6.2-19.0)0.69 (0.31-1.53)Chemo866.5 (5.4-8.4)546.5 (5.4-7.8)317.2 (5.2-11.6)207.5 (2.9-14.7)Patients Without Liver MetastasesPembro22510.9 (9.2-12.6)0.95 (0.78-1.17)14612.4 (10.5-14.2)0.82 (0.64-1.05)7213.0 (10.1-17.2)0.80 (0.55-1.16)4416.0 (11.4-27.1)0.57 (0.33-0.95)Chemo22412.6 (10.6-13.9)14812.6 (9.8-13.6)6712.7 (9.8-15.8)3214.3 (8.3-16.8)

Citation Format: Eric Winer, Oleg Lipatov, Seock-Ah Im, Anthony Goncalves, Keun Seok Lee, Peter Schmid, Laura Testa, Isabell Witzel, Shoichiro Ohtani, NIcholas Turner, Stefania Zambelli, Nadia Harbeck, Fabrice Andre, Rebecca Dent, Jianxin Lin, Vassiliki Karantza, Jaime Mejia, Javier Cortes. Pembrolizumab versus chemotherapy for previously treated metastatic triple-negative breast cancer (KEYNOTE-119): Efficacy in patients with lung or liver metastases [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 PS12-01.

Personalized Risk-Benefit Ratio Adaptation of Breast Cancer Care at the Epicenter of COVID-19 Outbreak

Northern Italy has been one of the European regions reporting the highest number of COVID-19 cases and deaths. The pandemic spread has challenged the National Health System, requiring reallocation of most of the available health care resources to treat COVID-19-positive patients, generating a competition with other health care needs, including cancer. Patients with cancer are at higher risk of developing critical illness after COVID-19 infection. Thus, mitigation strategies should be adopted to reduce the likelihood of infection in all patients with cancer. At the same time, suboptimal care and treatments may result in worse cancer-related outcome. In this article, we attempt to estimate the individual risk-benefit balance to define personalized strategies for optimal breast cancer management, avoiding as much as possible a general untailored approach. We discuss and report the strategies our Breast Unit adopted from the beginning of the COVID-19 outbreak to ensure the continuum of the best possible cancer care for our patients while mitigating the risk of infection, despite limited health care resources. IMPLICATIONS FOR PRACTICE: Managing patients with breast cancer during the COVID-19 outbreak is challenging. The present work highlights the need to estimate the individual patient risk of infection, which depends on both epidemiological considerations and individual clinical characteristics. The management of patients with breast cancer should be adapted and personalized according to the balance between COVID-19-related risk and the expected benefit of treatments. This work also provides useful suggestions on the modality of patient triage, the conduct of clinical trials, the management of an oncologic team, and the approach to patients' and health workers' psychological distress.

Modulation by treatment of tumor infiltrating lymphocytes (TILs) and PDL1 expression in triple-negative breast cancer in the ETNA trial

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Background: We assessed TILs and PDL1 expression before, during and after neoadjuvant treatment in TNBC patients enrolled in the ETNA study, and investigated associations with clinical outcome. Methods: In ETNA patients randomly received paclitaxel or nab-paclitaxel followed by 4 cycles of an anthracycline regimen, including 219 centrally confirmed TNBC. We successfully measured stromal and intratumoral TILs (sTILs, iTILs) and PDL1 status (Ventana SP142, IC≥1%) on biopsies before [n = 186/213 (84.9%)], on d1 cycle 2 (d1c2) of therapy [n = 41/186 (22.0%)], and at surgery [SX, n = 65/129 (34.9%)]. We investigated the expression and modulation over time of TILs and PDL1 and their association with pCR and event-free survival (EFS). Results: Prevalence of PDL1+ was 35.5% (baseline), 20.6% (d1c2) and 30.1% (SX). At each time-point sTILs and iTILs were higher in PDL1+ cases (p≤0.01). An effect of age of the tumor blocks (5-7.5 years) or pre-analytical issues could not be ruled out for the relatively low rate of PDL1 positivity. Paired PDL1 at baseline and d1c2 showed conversion in 25.7% (pos to neg [11.4%] or neg to pos [14.3%]). Comparing PDL1 at baseline and SX, the conversion rate was 30% (pos to neg [8.3%] or neg to pos [21.6%]). sTILs and iTILs significantly increased at cycle 2, more significantly in pCR (p≤0.001) than in RD (p≤0.05) cases, and a not significant trend of decrease was observed at surgery PDL1+ tumors had a higher pCR rate (54.7% vs 32.5%, p = 0.004). PDL1 retained significance (OR 2.00 [1.04-3.88], p = 0.039) after adjustment for sTILs (OR 1.21 [1.03-1.42], p = 0.021). High iTILs and sTILs at d1c2, but not PDL1 status, were predictive of pCR. Notably, adjusting for sTILs, PDL1+ tumors at d1c2 showed a trend for association with lower pCR rate (OR 0.06 [0.01-1.15], p = 0.062). sTILs at cycle 2 was the most informative variable (OR 1.61 [1.28-1.61], p = 0.004) and provided independent information to baseline biomarkers. Baseline PDL1 and biomarkers at cycle 2 were not associated with EFS. In surgical samples with RD, higher sTILs, but not iTILs and PDL1 status, were associated with a trend for a lower risk of recurrence (HR 0.19 [0.02-1.39], p = 0.068). Conclusions: sTILs assessment on core biopsies after one cycle of taxane is a promising early biomarker of pCR. PDL1, as well as sTILs and iTILs, provided independent prediction of pCR and were strongly modulated by treatment. The modulation of PDL1 expression should be considered whenever PDL1 is assessed in view of identifying candidates to atezolizumab in 1st line advanced setting.

Abstract P3-11-10: Health-related quality of life (HRQoL) in monarcHER: Abemaciclib plus trastuzumab with or without fulvestrant versus trastuzumab plus standard-of-care chemotherapy in HR+, HER2+ advanced breast cancer

Background: Abemaciclib is an oral selective inhibitor of cyclin-dependent kinases 4 and 6 approved for hormone receptor (HR)+, human epidermal growth factor receptor 2 (HER2)- metastatic breast cancer. In the randomized, 3-arm, phase 2 study monarcHER (NCT02675231) for HR+, HER2+ advanced breast cancer (ABC), abemaciclib in combination with trastuzumab (T) and fulvestrant (F) significantly improved investigator-assessed progression-free survival (whereas abemaciclib + T did not) versus (vs) T + physician’s choice of chemotherapy and demonstrated a tolerable safety profile. Here, patient-reported HRQoL, functioning, and symptoms are reported.

Methods: In monarcHER, 237 postmenopausal (surgical, natural, or chemical ovarian suppression) women with ABC and ≥2 prior HER2+ directed therapies in the advanced setting were randomized 1:1:1 to abemaciclib (150 mg PO Q12H every 21 days) + T (IV infusion on D1 every 21 days) with F (500 mg IM on Cycle 1 D1 and D15 and Cycle 2 D8, then Q4W; Arm A) or without F (Arm B) vs T + physician’s choice of chemotherapy (per label every 21 days; Arm C). Supportive measures to manage diarrhea were permitted. Patient-reported outcomes were measured at baseline and at each cycle using the modified Brief Pain Inventory-short form (mBPI-sf) and European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30). The EuroQol 5-Dimension 5 Level (EQ-5D 5L) questionnaire was also collected. Higher scores on EORTC QLQ-C30 functional and health status/QoL scales indicate improvement whereas higher scores on EORTC QLQ-C30 symptom scales and mBPI-sf indicate worsening of symptoms/pain. The EQ-5D 5L index score was calculated from a set of item weights to derive a score of 0-1, with 1 representing the best health status. Treatment arm comparisons of change from baseline (all post-baseline visits) were conducted using a mixed model repeated measure, with .05 considered statistically significant. Clinical meaningfulness was defined as a ≥10-point score change from baseline (on a 0-100 scale) for EORTC QLQ-C30 and a 2-point score change from baseline for mBPI-sf.

Results: Patient-reported outcome compliance rates were ≥90% through Cycle 15; the range for median duration of each treatment component of each arm was 7.5-10.0 cycles. Overall, no statistically significant or clinically meaningful changes from baseline differences were observed between treatment arms for mBPI-sf pain scores or EORTC QLQ-C30 global health score, function scales, or for symptoms of fatigue, dyspnea, appetite loss, or financial difficulties. Least square (LS) mean change from baseline differences showed statistically significant improvements in Arm A vs C for EORTC QLQ-C30 symptoms of pain (-6.81; p=.026) and insomnia (-6.39; p=.041). Worsening for the symptom of nausea/vomiting was statistically significant but not clinically meaningful in Arm A vs C (4.08; p=.043). Diarrhea showed a statistically significant and clinically meaningful worsening in Arm A vs C (19.27; p&lt;.001). A by-cycle analysis showed mean nausea/vomiting and diarrhea symptom scores were generally higher during earlier visits and returned to near-baseline levels after treatment discontinuation. The EQ-5D 5L index score improved in Arm A vs C, with an LS mean change from baseline difference of .05 (p=.033).

Conclusions: Quality of life was maintained for patient-reported pain, global health, functioning, and most symptoms when abemaciclib was added to T + F compared with physician’s choice of chemotherapy in patients with HR+, HER2+ ABC. Gastrointestinal-related symptoms were transient and consistent with the manageable, reversible adverse event profile.

Citation Format: Sara M Tolaney, Andrew M Wardley, Stefania Zambelli, John F. Hilton, Tiffany A Troso-Sandoval, Francesco Ricci, Seock-Ah Im, Sung-Bae Kim, Stephen RD Johnston, Arlene Chan, Shom Goel, Kristen Catron, Zhengyu Yang, M. Corona Gianford, Gregory L Price, Fabrice André. Health-related quality of life (HRQoL) in monarcHER: Abemaciclib plus trastuzumab with or without fulvestrant versus trastuzumab plus standard-of-care chemotherapy in HR+, HER2+ advanced breast cancer [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 P3-11-10.

Abstract P4-05-09: Molecular differences between high and low tumor mutational burden (TMB) across breast cancer (BC) subtypes

Background. High-TMB (HTMB) is an emerging promising agnostic biomarker for predicting benefit from immune-checkpoint inhibitors, independently of tumor type. At ASCO 2019, the TAPUR trial reported an interesting 21% ORR in heavily pretreated metastatic BC patients with very HTMB [vHTMB, ≥9 mutations/megabase (Muts/Mb)]. We aimed to define the differential gene expression and methylation landscape between low and high TMB in each BC subtype. Methods. In TCGA, we identified 848 patients with WES data available for TMB estimation. [ER+/HER2- (LumA by PAM50)) n = 364; ER+/HER2- (LumB by PAM50), n = 147; HER2+, n = 158; and TN, n = 179]. High TMB was defined according to two different cut-offs: ≥9 (vHTMB) and≥5 Muts/Mb (HTMB). The second arbitrary cut-off was used to define a larger group allowing to better characterize the different molecular landscapes associated with high and low TMB in each BC subtype. The HTMB group was compared with an equal number of tumors with low TMB. We assessed the differential RNA expression and methylation of single genes and pathways (defined using Gene Ontology - GO). “Common” genes and pathways were defined as recurrently associated with TMB (p&lt;0.05) in all subtypes and with a combined p value ≤0.00001. Results. The overall prevalence of vHTMB (≥9) was 4.5%, with no substantial differences across subtypes (4.4%, LumA; 4.8% LumB; 5.7% HER2+; 3.3% TN). The prevalence of HTMB (≥5) was 13.7%, but it was different across BC subtypes (p=8.0E-07) (8.2%, LumA; 12.9% LumB; 13.3% HER2+; 25.7% TN). We found more “common” genes down-regulated (n=70) than up-regulated (n=3) in HTMB group. Two of these three genes (HSPE1 and FEZF1.AS1) have been associated with poor prognosis in BC. When we considered the “common” pathways, only 3 were up-regulated in HTMB, all implicated in post-transcriptional repression of gene expression (gene silencing by miRNA and mRNA binding involved in post-transcriptional gene silencing). Conversely, 66 were significantly down-regulated (including transcription coregulator and coactivator activity, protein serine/threonine kinase activity and ubiquitin-protein transferase activity and binding). Some genes and pathways were associated with TMB only in a specific BC subtype (p ≤0.00001). For instance, 16 pathways were down-regulated in the HTMB group of TNBC. These inlcuded 12 pathways implicated in immune response. Conversely, in LumB, 11 pathways were up-regulated in HTMB group and implicated in immune response. Intrestingly, these pathways were all significantly down-regulated in the HTMB group of LumA and TN. In HTMB group, we found 7 and 4 “common” genes hypermetylated and hypomethylated, respectively. Four pathways were commonly hypermethylated (chromatin silencing at rDNA, telomere organization and positive regulation of G1/S transition of mitotic cell cycle) and five were hypomethilated (including mitotic sister chromatid segregation). Considering private alterations, in TNBC, 23 of 27 significant pathways were hypermetylated in HTMB group including double-strand break repair via nonhomologous end joining, epigenetic negative regulation of gene expression, and regulation of gene silencing by miRNA. Conclusions. Very-high TMB which is considered potentially druggable (≥9 Muts/Mb) is rare in BC, and equally frequent in all subtypes. Instead, HTMB (≥5 Muts/Mb) is more frequent in TNBC. BCs with HTMB had a different molecular landscape. Overall, several genes are recurrently down-regulated in HTMB group, and this is at least partly due to miRNA regulated post-trascriptional silencing, which might rapresents a new mechanism of immune escape. The positive association between TMB and immune genes in LumB, as well as the negative association in TN and LumA, suggest that immune editing and surveillance might be dependent on the molecular context.

Citation Format: Luca Licata, Barbara Galbardi, Balázs Győrffy, Thomas Karn, Lorenzo Sica, Alessia Rognone, Patrizia Zucchinelli, Daniela Aldrighetti, Stefania Zambelli, Luca Gianni, Giampaolo Bianchini. Molecular differences between high and low tumor mutational burden (TMB) across breast cancer (BC) subtypes [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 P4-05-09.

Abstract P5-06-21: Prognostic and predictive value of PML in the ETNA study and the TCGA

Background. Although long considered a tumor suppressor gene, PML (promyelocytic leukemia) also plays tumor-promoting functions in specific contexts. In vitro and in vivo studies have demonstrated that PML is upregulated by HIF-1α transcriptional activation in triple-negative breast cancer (TNBC) cells and it is implicated in promoting metastasis downstream of HIF-1α. This pro-metastatic function of PML is inhibited by arsenic trioxide, a pharmacological compound currently in use in acute promyelocytic leukemia. However, the clinical relevance of PML expression in BC has not been extensively investigated. In this study, we evaluated the association of PML expression with clinic-pathological factors and outcome (pathological complete response -pCR- and risk of recurrence) in the ETNA trial, and risk of recurrence in the TCGA. Methods. In the ETNA study (NCT01822314) 695 patients with HER2-negative breast cancer (BC) were randomized to receive neoadjuvant paclitaxel or nab-paclitaxel followed by 4 cycles of an anthracycline regimen. In the ITT study population, the two treatments did not show significantly different rates of pCR nor different Event-Free Survival (EFS) (Gianni JAMA Oncol 2018, Gianni ASCO 2019). A central histologic assessment of ER, PgR, HER2 status and Ki67 was mandatory. We evaluated PML expression by immunohistochemistry using the continuous histoscore (H-score) on pre-treatment core biopsies. The H-score is generated from the estimation of the percentage of cells with no (0), light (1+), moderate (2+) and strong (3+) intensity staining, and the corresponding score is generated with the following algorithm: [1 × (% cells 1+) + 2 × (% cells 2+) + 3 × (% cells 3+)]. We evaluated the association of PML with clinic-pathological features and clinical outcomes (pCR and EFS) in triple negative (TN) and in LuminalB-like (ER+ and/or PgR+, Ki67≥14%) groups. We also investigated the association between PML mRNA expression (RNA-seq) and DFS in HER2-negative BC (TN, n=192; ER+/HER2-, n=702) in the TCGA dataset. Results. In the ETNA study, PML was successfully assessed and valuable in 491 pts (70.6%). The average PML expression was 126.3 (median 120, range 0-295). In the ETNA trial, TNBC showed the highest expression of PML (p&lt;1.0E-10). Within LumB-like tumors, the group with intermediate proliferation (Ki67 14-20%, LumB-int) had higher PML expression than the high proliferation group (Ki67&gt;20%, LumB-high) (p=0.0005). However, within the LumB-high group, higher proliferation (Ki67&gt;40%) showed a higher expression of PML (p=0.025), suggesting a non-linear relationship between PML and proliferation in luminal tumors. In LumB-high, PML was higher in PgR-negative tumors (p=1.0E-5). Finally, PML showed a positive association with higher stromal tumor-infiltrating lymphocytes (sTILs) both in LumB-like and TN group (p=0.019 and p=0.001, respectively). PML expression was not significantly associated with pCR and risk of recurrence in LumB-like nor in TN BC.In the TCGA dataset also PML expression was highest in the TN group (p&lt;1.0E-10). No association was found between PML expression and risk of recurrence in any molecular subgroup. Conclusions. PML expression assessed by IHC in the ETNA trial was not predictive of likelihood of pCR nor of risk of recurrence in LumB-like and TN breast cancer. PML mRNA expression was not prognostic in TN and LumB-like tumors also in the TCGA dataset. Some interesting associations with biological features emerged which warrants biological interpretation of the complex role of PML in breast cancer. Supported in part by an unrestricted grant from Celgene Sarl, Swizerland

Citation Format: Stefania Zambelli, Chanel Smart, Giampaolo Bianchini, Isabella Sassi, Mauro Mansutti, Antonio Anton, Lourdes Calvo, Giancarlo Bisagni, Begona Bermejo, Martina Uggè, Barbara Galbardi, Vladimir Semiglazov, Marc Thill, Jose Ignacio Chacon, Arlene Chan, Serafin Morales Murillo, Isabel Alvarez, Ainhara Lahuerta, Patrizia Zucchinelli, Claudio Doglioni, Pinuccia Valagussa, Ignasi Tusquets, Luca Gianni, Rosa Bernardi. Prognostic and predictive value of PML in the ETNA study and the TCGA [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 P5-06-21.

Ki67 during and after neoadjuvant trastuzumab, pertuzumab and palbociclib plus or minus fulvestrant in HER2 and ER-positive breast cancer: The NA-PHER2 Michelangelo study

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Background: Downregulation of Ki67 by neoadjuvant endocrine therapy predicts activity of endocrine treatments in hormone receptors positive breast cancer. NA-PHER2 is an exploratory phase II study (NCT02530424) assessing Ki67 changes in patients with HER2+ and ER+ breast cancer undergoing dual HER2 block and palbociclib. Cohort A of the NA-PHER2 showed significant decrease of Ki67 at week 2 and at surgery and pathological complete response (pCR) in 27% of patients (Lancet Oncol 2018). Methods: After completing cohort A two additional cohorts were started. In Cohort B cases with HER2 3+ or amplified unilateral breast cancer received therapy with dual block and palbociclib without fulvestrant. In Cohort C tumors with Ki67 >20% and HER2 low (1+/2+, no amplification) received also fulvestrant. Trastuzumab and pertuzumab q3 wks were dosed for 6 cycles and palbociclib for 5 cycles (125 mg po q.d. 3q4 wks). Fulvestrant in Cohort C was given im 500 mg q4 wks for 5 cycles. Primary endpoint was Ki67 change from baseline to 2 weeks and at surgery. Results: 26 eligible patients in cohort B and 23 in cohort C with centrally confirmed HER2 and ER status were recruited. Ki67 was centrally assessed. Main results are reported in the table. Clinical trial information: NCT02530424. The most frequent G >=3 adverse events were neutropenia (36%) and gastrointestinal disorders (12%). Conclusions: Dual block of HER2 and palbociclib caused robust persistent decrease of Ki67 as in cohort A. In cohort B without endocrine therapy there also were pCR and high objective response rate. Effects on Ki67 and ORR were similar in HER2 low tumors. The chemo-free approach of NA-PHER2 leads to promising therapeutic effects and deserves investigation in ER+ HER2+ tumors to spare the toxicity of chemotherapy, and in HER2-low tumors, in which functional activation of HER2 may lead to resistance to endocrine therapy. Supported in part by unrestricted grants of Pfizer Italia S.r.l. and Roche S.p.a. Italia.[Table: see text]

Abstract P4-04-04: Triple-negative (TN) and HER2+ breast cancers (BC) have different immune milieu in primary and metastatic tumors

Background: In TN and HER2+ early BCs, a high immune infiltration is linked to good prognosis and improved treatment benefit. Little is known about the characteristics of the immune milieu of BCs in metastatic disease. We aimed to investigate differences of the immune microenvironment between cohorts of primary early breast cancer (EBC) and metastatic (MBC) tumors according to molecular subtypes.

Methods: We identified publicly available gene expression profiles (GEPs) of MBCs profiled either on Agilent (n=12, cohort I) or AffymetrixU133A (n=36, cohort II). These included 21 ER-/HER2- (TN), 10 HER2+ and 17 ER+/HER2- (Luminal). From GEPs of EBC profiled on the same platforms, we randomly selected two cohorts with the same molecular subtype composition (n=65 and n=230) and compared them with MBCs. We assessed differential expression of 40 pre-selected immune genes belonging to six immune-related metagenes [CD8, IGG and MHC2, related to T cells, plasma cells and antigen presenting cells respectively; MHC1, STAT1 and IF.I related to HLA class I genes; and genes modulated by interferon (Gianni L SABCS 2012)]. We also evaluated β2-microglobulin (B2M), for its role in the MHC1 complex, and an immune signature associated with benefit from pembrolizumab in melanoma (Ribas A ASCO 2015).

Results: In cohort I (Agilent), only 33 genes were annotated. Overall, 16/33 (48.4%) genes had a significantly lower expression in MBC (p&lt;0.05). In TN and HER2+ MBCs 18 and 11 genes were significantly lower than in EBC, respectively (p&lt;0.05) (6 in both), while only one was lower in luminal MBCs (IGHM). In cohort II (Affymetrix), 26/40 genes (65%) had lower expression in MBC (p&lt;0.05). Considering molecular subtypes, 25 and 19 genes were lower in TN and HER2+, respectively (17 in both), and only one in ER+/HER2- (IL7R). In ER+/HER2- one gene was higher in MBC (IFIT2). In TN and HER2+ the genes with lower expression in MBC belong to all immune functional categories, in particular MHC1 (HLA-A, B and C), STAT1 (STAT1, CXCL10, CXCL11, GBP1), MHC2 (HLA-DQB1 and DRB4) and T cells (CD52, IL7R and TRBC1). B2M was significantly lower in all MBC patients, and in HER2+ and TN groups both in cohort I (p=0.0002; p=0.006 and p=0.0005, respectively) and in cohort II (p&lt;1E10-6; p=0.0008 and p=0.00004, respectively), while it was modestly lower in ER+/HER2- in cohort II only (p=0.027). The signature associated with benefit from pembrolizumab in melanoma was significantly lower in TN and HER2+ MBC in both cohort I (p=0.003) and cohort II (p=0.001), but not in luminal cases.

Conclusions: TN and HER2+ MBCs have a "colder" immune microenvironment than primary tumors, with significantly lower expression of genes related to immune response and to antigen presentation (B2M and MHC1). This is consistent with the lower TILs we have described in a small series of paired EBC-MBC (Ogiya R ASCO 2015), suggesting the engagement of mechanisms of immune escape during the metastatic process. However, the "cold" immune milieu observed in MBC could also result from selection of low immunogenic tumors more likely to relapse. Our findings suggest that use of immune-checkpoints inhibitors in MBCs may require the combination with agents able to turn on an immunogenic response.

Citation Format: Bianchini G, Riba M, Zambelli S, Safonov A, Ogiya R, Jiang T, Hatzis C, Niikura N, Zambetti M, Iwamoto T, Pusztai L, Gianni L. Triple-negative (TN) and HER2+ breast cancers (BC) have different immune milieu in primary and metastatic tumors. [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 P4-04-04.

Endoscopic mucosal resection in high- and low-volume centers: a prospective multicentric study

BACKGROUND

Endoscopic mucosal resection (EMR) is an effective therapeutic technique well-standardized worldwide for the treatment of gastrointestinal neoplasm limited to the mucosal layer. To date, no study has compared technical and clinical differences based on the number of EMRs performed per year. This study aimed to compare EMR technical success, complications, and clinical outcome between low-volume centers (LVCs) and high-volume centers (HVCs). A total of nine endoscopic centers were included in the study.

METHODS

This prospective study investigated consecutive patients with sessile polyps or flat colorectal lesions 1 cm or larger referred for EMR.

RESULTS

A total of 427 lesions were resected in 384 patients at nine endoscopic centers. Males accounted for 60.4% and females for 39.6% of the patients. Most of the EMRs (84.8%) were performed in HVCs and only 15.2% in LVCs. All the lesions were resected in only one session. Argon plasma coagulation was performed on the margins of piecemeal resection in 15.7% of the patients in HVCs only. Complete excision was achieved for 98.6% of the lesions in HVCs and 98.8% of the lesions in LVCs. The complication rate was 4.4% in HVCs and 4.6% in LVCs (p = 0.94). Delayed bleeding occurred in 2.5% of the HVC cases and 3.1% of the LVC cases. Perforation occurred in 1.9% of the HVC cases and 1.5% of the LVC cases (p = 1.00). Recurrences were experienced with 15% of the lesions: 15.5% in HVCs and 14% in LVCs (p = 0.79).

CONCLUSIONS

The study showed that EMR can be performed also in LVC.

Ki-67 scores and AgNor counts in transitional cell carcinoma of the bladder: apparent lack of prognostic value

The cellular proliferative state of 18 incident cases of transitional cell carcinomas of the bladder treated with transurethral resection was blindly determined by two independent observers using Ki-67 monoclonal antibody and silver stain for nucleolar organizer regions (AgNORs). Ki-67 scores were significantly related to histological grade (WHO) (rs = 0.65, p < 0.01) and clinical stage (UICC) (rs = 0.46, p < 0.05). However, the follow-up analysis over a six year period did not demonstrate significant relationship between Ki-67 values and survival. AgNOR counting did not show significant association with any of the variables under study. The results of this investigation and the review of the pertinent literature suggest that the assessment of cell proliferation of bladder carcinoma by means of Ki-67 and AgNOR techniques is far from having immediate direct influence on patient management.

[Urethral lesion caused by a condom: description of a case]

We report a case of severe urethral lesion in a male patient with a vascular cerebral stroke. The wrong application of condom catheter without pain or other symptoms developed the urethral lesion.

[Hydatidosis of the psoas muscle. Description of a case and review of the literature]

A rare case of echinococcus cyst of the psoas muscle is described in a 64-year-old male patient. Following evaluation with echotomography, CT and MRI, he was treated with Albendazole for five months. After there the cyst was evacuated by ultrasound-guided aspiration and he received another course of chemotherapy. Recent evaluation revealed the patient is well and cyst-free.

[Correlation between histological grading and cell growth fraction in bladder tumors]

30 carcinomas and 1 papilloma of bladder were studied by immunohistochemical method with a monoclonal antibody Ki-67 (Dako-PC) reacting with a nuclear antigen present in cells of the mitotic phases G1, S, G2 and M. Authors would like determine the growth ratio (correlation between the number of cells in mitotic cycle and the total number of cells) of the neoplastic cell populations to compare it to the grading of themselves established by traditional parameters. It was shown, as in other carcinoma type, that the down grading correspondent with augmentation of cell growth fraction. It is of interest to verify that among carcinoma of different grading there are values partially corresponding for the growth fraction. This confirm what are going to demonstrate all those studies by means of flow cytometry and image analysis: grading of neoplasias as now fixed, doesn't give a satisfactory index for prognosis.

[Computerized tomography in Peyronie's disease. Clinico-radiological comparison]

The diagnostic capabilities of Computed Tomography (CT) in the study of Peyronie's disease are assessed. Twenty-four patients, with different symptoms and a variety of findings on physical examination (from normal to large painful plaques), were studied with third-generation CT equipment. CT defined the normal pattern of the albuginea, as a hyperdense (ranging from 80 to 100 HU) thin and regular line on the periphery of the corpora cavernosa. Pathologic features such as irregularities, disruptions and calcifications of the tunica can be identified; irregularities are shown as circumscribed zones of hyper or hypodensity, disruptions as small or large areas of complete absence of the thin regular line of albuginea. Calcifications are identified as hyperdense nodular or plaquelike areas of 200-300 HU. When physical examination and CT patterns are compared, the reliability of the method is revealed. It provides an accurate definition of the albugineal lesions, imaging all abnormalities detected on physical examination and demonstrating additional, non-palpable and doubtful lesions. Physical examination and CT findings concurred in 19 cases (79%), whereas disagreement was observed in 5 (12%). In 3 cases CT showed calcified plaques not revealed on physical examination; in 2 cases the plaques revealed by palpation were not confirmed by CT. Furthermore there may be a connection between CT aspects of the albuginea and the hystological findings in the disease: irregularities could represent the early stage, interruptions the mid-stage and calcifications irreversible final abnormalities. CT, being a non-traumatic, harmless diagnostic method, improves the clinical evaluation of the patient and can facilitate the choice of the most suitable therapeutic modalities, as well as the follow-up of their results.

[Liquid embolization of the renal artery with absolute ethanol]

Absolute ethanol is a new agent for use in embolization which has demonstrated excellent efficacy, is simple to manage, and above all is innocuous in case of reflux into the aorta. A part from provoking irreversible occlusion of the complete renal artery circle, embolization with ethanol provokes direct cellular toxic necrosis comparable with a true mummification. This is of fundamental importance during palliative embolization for renal cancer or in all cases of medical nephrectomy for non-neoplastic disease. Results of the use of liquid embolization of the renal artery with absolute ethanol are presented, the technique, described, and mechanisms of action analyzed based on histologic findings.

Total pelvic arterial embolization in a case of massive vesical and vaginal bleeding by pelvis carcinomatosis

A case of massive vesical and vaginal bleeding due to a primitive uterine cancer that relapsed hemorragically after bilateral hypogastric embolization and required an additional embolization of all arterial sources supplying the tumor is reported.