Second-line treatment strategies for RAS wild-type colorectal cancer: A systematic review and Network Meta-analysis (NMA)

BACKGROUND

The optimal strategy for second-line (IIL) treatment in KRAS wt metastatic colorectal cancer (mCRC) is not determined yet.

METHODS

A random-effect NMA of phase II/III RCTs was conducted to evaluate IIL treatment for all-RAS wt mCRC, comparing anti-EGFR or anti-VEGF, and chemotherapy (CT).

RESULTS

Overall, 11 RCTs (3613 patients) were included. In KRAS wt patients, PFS was improved with anti-VEGF (HR 0.43) and anti-EGFR (HR 0.63) vs CT. However, anti-VEGF based therapy had the highest likelihood of being ranked as the best treatment in terms of PFS (SUCRA 99.3%) and OS (SUCRA 99.4%). Bevacizumab-based treatment is most likely to be the best treatment in terms of PFS (SUCRA 89.1%) and OS (SUCRA 86.7%).

CONCLUSIONS

Second line treatment with anti-VEGF and anti-EGFR improved PFS in mCRC patients, however, anti-VEGF based therapy, particularly CT plus bevacizumab, is the best treatment according to SUCRA in terms of PFS and OS.

Estimating survival in patients with melanoma brain metastases: prognostic value of lactate dehydrogenase

Patients with melanoma brain metastases (MBM) have poor prognosis, albeit advances in locoregional and systemic treatments. The melanoma-specific Graded Prognostic Assessment (GPA) effectively stratifies survival for patients with MBM. Nevertheless, lactate dehydrogenase (LDH), a well known prognostic factor for patients with melanoma, is not represented in the GPA scores and might add prognostic information for patients with MBM. In this study, 150 consecutive patients with MBM were retrospectively analyzed with the aim of evaluating independent prognostic factors for MBM patients, including LDH. Furthermore, we implemented a disease-specific prognostic score and estimated survival according to treatment modalities. On the basis of multivariable Cox regression analyses, six prognostic factors (age, BRAF status, number of MBM, number of extracranial metastatic sites, performance status, and LDH level) resulted statistically significant in terms of survival and were combined in a prognostic score to stratify patients in distinct prognostic groups ( P  < 0.0001). Among treatment modalities, a multimodal approach with stereotactic radiosurgery or neurosurgery associated with systemic therapy showed the best outcome (median overall survival: 12.32 months, 95% confidence interval, 7.92-25.30). This is the first study to demonstrate that LDH has independent prognostic value for patients with MBM and might be used to improve prognostic stratification, albeit external validation is mandatory. Survival of patients with MBM is affected by both disease-specific risk factors and treatment modalities, with locoregional treatments associated with better outcomes.

CDK4/6 Inhibitors in Melanoma: A Comprehensive Review

Historically, metastatic melanoma was considered a highly lethal disease. However, recent advances in drug development have allowed a significative improvement in prognosis. In particular, BRAF/MEK inhibitors and anti-PD1 antibodies have completely revolutionized the management of this disease. Nonetheless, not all patients derive a benefit or a durable benefit from these therapies. To overtake this challenges, new clinically active compounds are being tested in the context of clinical trials. CDK4/6 inhibitors are drugs already available in clinical practice and preliminary evidence showed a promising activity also in melanoma. Herein we review the available literature to depict a comprehensive landscape about CDK4/6 inhibitors in melanoma. We present the molecular and genetic background that might justify the usage of these drugs, the preclinical evidence, the clinical available data, and the most promising ongoing clinical trials.

LDH as prognostic factor in second line treatment for advanced gastric cancer: The LINE study

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Background: Lactate dehydrogenase (LDH) is recognized as indirect marker of tumor hypoxia and angiogenesis for several solid tumors. Ramucirumab is the first antiangiogenic agent approved for second-line therapy in advanced gastric cancer (GC), alone or in association with chemotherapy. To date, no reliable biomarkers can predict the potential benefit from anti-VEGFR2 treatment. This retrospective multicenter study aimed to assess the prognostic role of baseline LDH levels in patients (pts) undergoing second-line treatment for advanced GC. Methods: The study analyzed a retrospective cohort of consecutive advanced GC pts treated with second line therapy at IRCCS, CRO of Aviano and at Mauriziano Hospital of Torino, Italy, from 2010 to 2020. LDH levels prior to second-line treatment were classified as low-normal or high and standardized according to the upper limit of the reference range. To better determine the optimal LDH cut-off value, ROC analysis was performed (using PFS < 3 months as binary outcome). Normalized LDH values were subsequently sorted according to the ROC curve cut-off in order to test the association with overall survival (OS) through the Kaplan-Meier method and compared using the Log-Rank test. A multivariate Cox regression analysis assessed the prognostic impact of normalized LDH levels for OS calculated from the start of second line treatment. Results: Overall, 125 pts were enrolled. Of these, 81 pts (64.80%) received ramucirumab alone or plus paclitaxel as second line treatment, while 44 (35.20%) had taxanes or fluoropyrimidines combined with irinotecan. Median age was 68 years, 93% had an ECOG PS ≤ 1, 64.80% was first diagnosed with metastatic disease and 40.80% underwent primary tumor resection. Median second line PFS and OS were 4.2 and 7.9 months, respectively. Baseline LDH values were available for 99 pts. ROC analysis identified a normalized LDH value of 0.83 as the optimized cut-off point to define pts with poor prognosis. At univariate analyses, surgery of the primary tumor (HR 0.51, 95% CI 0.31-0.82, p = 0.005) was associated with better OS, while low-normal BMI ( < 25 kg/m2) at second line start (HR 1.99, 95% CI 1.21-3.28, p = 0.007), normalized LDH values ≥ 0.83 (HR 1.86, 95% CI 1.13-3.07, p = 0.015) and PS > 1 (HR 5.65, 95% CI 2.29-13.92, p < 0.001) were associated with poorer outcome. At multivariable model, only PS > 1 was independently associated with poor prognosis (HR 9.93, 95% CI 3.27-30.08, p < 0.001). Subgroup analyses showed no significant heterogeneity in OS outcome according to normalized LDH levels between patients treated with or without ramucirumab. Conclusions: Elevated LDH levels are indicators of worse outcome in advanced gastric cancer pts. Notably, the LDH cut-off value identified a poor prognosis subgroup among pts with normal baseline levels, suggesting that current laboratory ranges could be suboptimal for patient stratification.

Refining neutropenia risk assessment in patients treated with first-line endocrine therapy (ET) and cyclin-dependent kinase 4/6 inhibitors (CDK4/6i) for metastatic breast cancer (MBC) through a cell-free DNA workflow (cfDNA)

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Background: The combination of ET and CDK4/6i is the current standard of care for hormone receptor (HR)-positive/HER2-negative MBC (luminal MBC), with neutropenia being the main dose limiting toxicity. We previously observed the potential association between leucocyte count (WBC) and different fractions of cell free circulating DNA (cfDNA) (Bortot et al 2020). The present study aimed to evaluate the feasibility of a cfDNA-based workflow as a new tool to assess the risk of treatment induced neutropenia. Methods: The study analyzed a prospective cohort 83 luminal MBC patients (pts) treated with first line ET and CDK4/6i in the CRO-2018-56 multicenter study from 2018 to 2021. cfDNA was characterized through droplet digital PCR (ddPCR) based on different ACTB DNA fragments lengths: short (s), medium (m) and long (l). Blood samples were collected before treatment start (BL) and at the first clinical evaluation after 3 months (E1). Associations between clinical characteristics, neutropenia and cfDNA were explored through Kruskal Wallis, time to G3 neutropenia (NG3) (TTN) was analyzed through log-rank and Cox regression. Results: Neutropenia was G3 in 44 out of 83 pts (53%) and G4 in 2 pts (2%). Median TTN was 1.8 months, 60% of NG3 occurred within 3.7 months. Overall, 74 pts (89%) resolved toxicity within 7 days, 10 pts (12%) reduced CDK4/6i dose after NG3. BL neutrophils count (Neu) and WBC were significantly lower in pts that developed NG3 (P = 0.0013 and P = 0.0020 respectively). De novo metastatic pts had numerically higher Neu (median 4825 vs 3895), but only a numerically lower risk of NG3 was observed (HR 0.53 P = 0.064). Although bone involvement was not associated with risk of developing NG3, the total number of metastatic lesions was associated with higher NG3 (P = 0.0016). In particular, > 5 metastatic lesions were associated with higher NG3 risk (p = 0.013). E1 ACTB_m was significantly lower with respect to BL in pts that experienced NG3 (median 100% vs 16%, P = 0.0136 in NG3 no vs yes) with a consistent impact on the risk of NG3 (HR: 2.81, P = 0.025). No associations were observed for the other ACTB fragment length fractions. BL Neu and ACTB_m dichotomized at the median were then combined to describe 4 distinct TTN risk groups (P = 0.0006). Interestingly, pts with low BL Neu and low E1 ACTB_m had a median TTN of 0.9 months, while pts with high BL Neu and high E1 ACTB_m have not experienced NG3 after a median follow-up of 16.1 months. Conclusions: The present study proofed the concept of using cfDNA to provide clinically meaningful data not only about tumor biology, but also for a comprehensive patient assessment. Based on these results, a prospective study focused on a multiparametric neutropenia risk assessment will be started.

Liquid biopsy for baseline evaluation of tumor burden in patients with hormone receptor-positive, HER2-negative metastatic breast cancer: A proof of principle study

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Background: Liquid biopsy-based biomarkers, including circulating tumor DNA (ctDNA), are increasingly important for the characterization of metastatic breast cancer (MBC). Currently, CA15.3 is the most commonly used serum marker for monitoring disease burden. To date, no liquid biopsy-based biomarkers have been proposed for this scope in clinical practice. Methods: The CRO-2018-56 multicenter study prospectively enrolled 83 patients (pts) with luminal-like MBC treated with first line endocrine therapy (ET) and CDK4/6 inhibitors. All pts were characterized for ctDNA through droplet digital PCR (ddPCR) in from 2018 to 2021. Clinicopathological and laboratory characteristics at baseline were tested for associations with tumor markers, ACTB fragments lengths, methylation status of ESR1 main promoters (expressed as promA and promB ratio, i.e., met_ratio) and ESR1/PIK3CA mutational status through Kruskal-Wallis test and Chi-square test. Prognosis was tested in terms of Progression Free Survival (PFS) and Overall Survival (OS) through log-rank test. Results: At baseline, in 26 (31%) pts disease was diagnosed as de novo metastatic, 66 (80%) pts had < 3 of metastatic sites, and 41 (49%) pts had < 5 of metastatic lesions. Bone metastases were detected in 53 (64%) pts, liver metastases in 21 (25%) pts, and lung lesions in 30 (36%) pts. A ctDNA-detected ESR1 mutation and a PIK3CA mutation were found in 15% of pts and in 34% pts, respectively. Met_ratio was > 1.5 in 35 (42%) of pts. Median CA15.3 was 48.2 U/mL and median CEA was 3.8 U/mL. Number of liver metastases and number of metastatic sites were significantly higher in pts with ESR1 mutation (respectively, P = 0.0055 and P = 0.0208). CA15.3 and ctDNA yield were significantly higher in pts with number of metastatic sites ≥ 3, (respectively, P = 0.0164, and P = 0.0239), while number of metastatic sites ≥ 3 and number of metastatic lesions ≥ 5 were significantly associated with CEA > 3.8 U/mL (respectively, P = 0.039, and P = 0.029). Presence of bone metastases was significantly associated with PIK3CA mutation (P = 0.040), while number of metastatic sites ≥ 3 was significantly associated with ESR1 mutation (P = 0.022). No association with tumor burden was observed for different ACTB DNA fragments lengths. Met_ratio > 1.5 was significantly associated with lower number of metastatic lesions (P = 0.031). Number of metastatic sites ≥ 3, high ctDNA yield and CEA were associated with worse OS (respectively P = 0.0465, P = 0.0250 and P = 0.0474), while only CEA impacted on PFS (P = 0.0097). Conclusions: In pts with luminal-like MBC, some liquid biopsy-based biomarkers (i.e., ctDNA-detected ESR1 and PIK3CA mutations, ctDNA yield) were significantly associated with the burden of disease. The potential clinical validity and utility of these results deserve to be tested in an expansion cohort.

Find the Flame: Predictive Biomarkers for Immunotherapy in Melanoma

Immunotherapy has revolutionized the therapeutic landscape of melanoma. In particular, checkpoint inhibition has shown to increase long-term outcome, and, in some cases, it can be virtually curative. However, the absence of clinically validated predictive biomarkers is one of the major causes of unpredictable efficacy of immunotherapy. Indeed, the availability of predictive biomarkers could allow a better stratification of patients, suggesting which type of drugs should be used in a certain clinical context and guiding clinicians in escalating or de-escalating therapy. However, the difficulty in obtaining clinically useful predictive biomarkers reflects the deep complexity of tumor biology. Biomarkers can be classified as tumor-intrinsic biomarkers, microenvironment biomarkers, and systemic biomarkers. Herein we review the available literature to classify and describe predictive biomarkers for checkpoint inhibition in melanoma with the aim of helping clinicians in the decision-making process. We also performed a meta-analysis on the predictive value of PDL-1.

Plasma-Based Longitudinal Evaluation of ESR1 Epigenetic Status in Hormone Receptor-Positive HER2-Negative Metastatic Breast Cancer

Background

Endocrine therapy (ET) is the mainstay of treatment for hormone receptor-positive human epidermal growth factor receptor 2 (HER2)-negative metastatic breast cancer; however, adaptive mechanisms emerge in about 25–30% of cases through alterations in the estrogen receptor ligand-binding domain, with a consequent ligand-independent estrogen receptor activity. Epigenetic-mediated events are less known and potentially involved in alternative mechanisms of resistance. The aim of this study was to test the feasibility of estrogen receptor 1 (ESR1) epigenetic characterization through liquid biopsy and to show its potential longitudinal application for an early ET sensitivity assessment.

Methods

A cohort of 49 women with hormone receptor-positive HER2-negative MBC was prospectively enrolled and characterized through circulating tumor DNA using methylation-specific droplet digital PCR (MS-ddPCR) before treatment start (BL) and after 3 months concomitantly with computed tomography (CT) scan restaging (EV1). ESR1 epigenetic status was defined by assessing the methylation of its main promoters (promA and promB). The most established cell-free tumor DNA (ctDNA) factors associated with ET resistance [ESR1 and phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha (PIK3CA) mutations] were assessed through next-generation sequencing. Associations were tested through Mann–Whitney U test, matched pairs variations through Wilcoxon signed rank test, and survival was analyzed by log-rank test.

Results

The ET backbone was mainly based on aromatase inhibitors (AIs) (70.83%) in association with CDK4/6 inhibitors (93.75%). Significantly lower promA levels at baseline were observed in patients with liver metastases (P = 0.0212) and in patients with ESR1 mutations (P = 0.0091). No significant impact on PFS was observed for promA (P = 0.3777) and promB (P = 0.7455) dichotomized at the median while a ≥2-fold increase in promB or in either promA or promB at EV1 resulted in a significantly worse prognosis (respectively P = 0.0189, P = 0.0294). A significant increase at EV1 was observed for promB among patients with PIK3CA mutation (P = 0.0173). A trend was observed for promB in ESR1 wild-type patients and for promA in the ESR1 mutant subgroup.

Conclusion

The study proofed the concept of an epigenetic characterization strategy based on ctDNA and is capable of being integrated in the current clinical workflow to give useful insights on treatment sensitivity.

"To Anticipate": Neoadjuvant Therapy in Melanoma with a Focus on Predictive Biomarkers

Despite surgical resection and adjuvant therapies, stage III melanomas still have a substantial risk of relapse. Neoadjuvant therapy is an emerging strategy that might offer superior efficacy compared to adjuvant therapy. Moreover, neoadjuvant therapy has some virtual advantages: it might allow for less demolitive surgery, permit the in vivo evaluation of drug efficacy, help tailor adjuvant treatments, and play a crucial role in innovative translational research. Herein, we review the available literature to explore the scientific background behind the neoadjuvant approach. We also discuss published clinical trials with a focus on predictive biomarkers and ongoing studies. Finally, we outline a possible framework for future neoadjuvant clinical trial development based on the International Neoadjuvant Melanoma Consortium guidelines.

Prognostic role of macrophage infiltration and monocyte-to-lymphocyte ratio in stage III colon cancer: The MIRROR study

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Background: Changes in peripheral blood cells composition may reflect immune microenvironment and its role in cancer growth. High monocyte-to-lymphocyte ratio (MLR) could be a marker of tumor’s recruitment of suppressive cells, showing a prognostic role. This study aimed to assess the prognostic impact of macrophage infiltration and MLR in stage III colon cancer (CC) patients (pts). Methods: This multicentric study retrospectively analyzed a consecutive cohort of 423 CC pts treated between 2008-2019 at the Cancer Centre of Aviano (Italy) (n = 300) and at the European Georges Pompidou Hospital of Paris (France) (n = 123). The association of MLR with disease-free survival (DFS) and overall survival (OS) was evaluated with Cox regression analyses. Random Forrest was implemented on python using h2oai. Performance was assessed in terms of accuracy (ACC) and Matthews Coefficient (MCC). Analyses was adjusted on classical prognostic factors of stage III CC such as pT, pN, grade, location, ECOG PS. Results: Overall, 77% had pT1-3, 30% pN2 and 73% G1-2 tumors. Interestingly, 25% had a lymphatic and vascular invasion, 42/230 (18%) had MSI status, 69/152(45%) and 19/114 (13%) were KRAS and BRAF mutant. 56% had CEA > 5. Pts were treated with fluoropyrimidine and oxaliplatin as adjuvant therapy. Notably, 130 cases were analyzed according to lymphocytic and macrophage infiltration (CD163, CD68, CD3, CD8). Of them, 78% had a CD163/CD8 ratio ≤3 and 74% a CD8/CD3 ratio ≤1.5. At median follow-up of 57 months, median DFS and OS were not reached, 31% of pts relapsed and 23% dead. By multivariate analysis, including statistically significant prognostic variables, CD163/CD8 ratio (HR 1.15, p = 0.039, 95%C.I. 1.1-1.32) and MLR > 0.45 (HR 2.98, p = 0.008, 95%C.I. 1.33-6.67) were associated with worse DFS. By multivariate analysis for OS, including statistically significant confounding variables, MLR > 0.45 (HR4.32, P = 0.012, 95%C.I. 1.37-9) and BRAF mutation predicted worse OS. According random survival forest for OS, CD68/CD3 were the first variable of importance (0.06), followed by MLR (0.009) and CD8 (0.007). Interestingly, high MLR followed by CEA, MSI, KRAS were the features linked with organotropism on liver (ACC 0.6 ±0.3), while high MLR, KRAS, pN, pT were mainly linked with lung colonization (ACC 0.6 ±0.2). Conclusions: High pre-treatment levels of MLR and CD163/CD8 ratio in stage III CC are independently associated with worse prognosis. The present study paves the way to a prospective validation of these promising cost-effective biomarkers.

Abstract P5-14-08: Predictors of relative dose intensity and early dose reduction in patients with metastatic breast cancer treated with palbociclib and endocrine therapy

Background: The combination of endocrine therapy with the cyclin-dependent kinases 4/6 inhibitor palbociclib was proven to be effective for the treatment of hormone receptor (HR)-positive/HER2-negative metastatic breast cancer (MBC). Although generally well tolerated, treatment delays and dose reductions are frequently observed with palbociclib, mainly due to severe neutropenia. Predictors of palbociclib-related toxicities are still unknown, as well as the clinical relevance of its relative dose intensity (RDI). Henceforth, this study aimed to identify baseline clinicopathological features associated with a RDI &lt;75% and early dose reduction (within the first 3 months of treatment). Secondarily, we explored the impact of RDI &lt;75% and early dose reduction on progression-free survival.

Methods: We reviewed data of 150 consecutive patients with HR-positive/HER2-negative MBC patients treated with palbociclib at two Italian cancer centers from 2017 to 2019. Eligible patients must have received at least 3 cycles of treatment. Those who experienced early suspension due to unacceptable toxicities were still eligible. RDI was calculated as the ratio of actual dose intensity (cumulative administered dose/treatment duration) and planned dose intensity (cumulative planned dose/planned treatment duration). The association of both RDI &lt;75% and early dose reduction with baseline clinicopathological features was assessed using multivariate logistic regression. The following variables were investigated as predictors of dose reduction: de novo vs. recurrent MBC, prior chemotherapy, treatment line, associated endocrine therapy, performance status (PS), weight, renal clearance, hemoglobin level, absolute white blood cell (WBC) count, absolute neutrophils count and absolute platelet count. A ROC analysis was performed to identify the best cut-off for baseline weight in predicting a RDI &lt;75%, while continuous laboratory variables were dichotomized according to clinically relevant cut-offs.

Results: Overall, 142 patients were deemed eligible. Of these patients, 98 (69.0%) were treated with palbociclib plus fulvestrant, 44 (31.0%) with palbociclib plus aromatase inhibitors, and 73 (51.4%) in the first-line setting. The median number of administered palbociclib cycles was 8 (range: 1-24) and 61 patients (43.0%) required at least a first-level dose reduction (29 within 3 months). Furthermore, the median time to first dose reduction was 3.22 months, with neutropenia being responsible for 85.24% of first-level dose reductions. In the whole cohort, median RDI was 90.5% (95.1% for patients without dose reduction and 80% for those who had received a dose reduction). Notably, 28 patients (19.7%) experienced a RDI &lt;75%. Through multivariate logistic regression, baseline weight ≤66 kg (OR 3.01, 95% CI: 1.08-8.35, p=0.03) and WBC ≤4.5 × 109/L (OR 3.15, 95% CI: 1.08-9.12, p=0.03) were independently associated with a RDI &lt;75%. Moreover, baseline weight ≤66 kg was also significantly correlated with early dose reduction (OR 2.77, 95% CI: 1.09-7.01, p=0.03). After a median follow-up of 11.76 months, median PFS was 13.99 months. When exploring potential prognostic factors, neither a RDI &lt;75% (HR 1.01, 95% CI: 0.52-1.95, p=0.97) nor a dose reduction within the first 3 months (HR 1.39, 95% CI: 0.67-2.91, p=0.31) did significantly impact PFS.

Conclusions: In our analysis, baseline weight and WBC were statistically associated with a RDI &lt;75% in patients with MBC treated with palbociclib. Furthermore, baseline weight was also able to predict an early dose reduction in the study population. Lastly, early dose reduction and RDI &lt;75% did not impact PFS. Although the small sample size and the limited follow-up, our results warrant further investigation in specifically designed trials.

Citation Format: Giacomo Pelizzari, Elisa Bertoli, Marco Giavarra, Carla Corvaja, Lorenzo Gerratana, Debora Basile, Michele Bartoletti, Camilla Lisanti, Lucia Bortot, Silvia Buriolla, Mattia Garutti, Debora Avoledo, Marta Bonotto, Lucia Da Ros, Silvia Bolzonello, Mauro Mansutti, Paola Di Nardo, Gianpiero Fasola, Simon Spazzapan, Alessandro M Minisini, Fabio Puglisi. Predictors of relative dose intensity and early dose reduction in patients with metastatic breast cancer treated with palbociclib and endocrine therapy [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 P5-14-08.

Role of anthracyclines in neoadjuvant anti-HER2 regimens for HER2+ breast cancer (BC): A network meta-analysis (NMA)

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Background: It is matter of current debate which would be the best chemotherapy backbone of neoadjuvant HER2-targeted therapy for HER2+ BC. The TRAIN 2 trial showed no significant difference in terms of pathological complete response (pCR) when anthracyclines–based (CTA) or anthracyclines–free regimens (CT) were combined with dual HER2 blockade. However, it remains unclear how anthracyclines may influence the relative benefit across different anti-HER2 treatments. Methods: A systematic review was conducted which included all phase II/III randomized clinical trials (RCTs) comparing different neoadjuvant regimens for HER2+ BC. pCR (yT0/isN0) was the outcome of interest. Indirect comparisons of all combination of anti-HER2 agents with CTA or CT were estimated with a random-effects frequentist NMA. Estimated pCR rates were inferred adopting a Bayesian NMA. Results: 17 RCTs (3933 patients) were included. Overall, 8 arms were identified, comprising all possible combinations of CTA and CT with trastuzumab (H), lapatinib (L) and dual HER2 blockade (D) but also CTA and D only. Odds ratios (OR) for pCR and 95% confidence interval (CI) of selected NMA comparisons are shown in the table. Estimated rates of pCR for each treatment and 95% credible interval (CrI) are reported in the table. Conclusions: Through indirect comparisons, no significant pCR gain was found for CTA vs CT when combined to D, H and L. In particular, considering double vs single-agent anti-HER2 regimens, D-CT remains superior to H-CTA, supporting a possible omission of anthracyclines when dual anti-HER2 block is used. On the contrary, our pooled estimate suggests a more relevant role for anthracyclines when comparing H-CT/A vs CTA. Moreover, we estimated a 4% pCR gain for D-CTA vs D-CT, and an 8% higher pCR rate for H-CTA vs H-CT. [Table: see text]