Optimizing abemaciclib-induced diarrhea management in patients with breast cancer: a pragmatic 2-group study using a postbiotic microbiota stabilizer

BACKGROUND

Abemaciclib-induced diarrhea is a relevant concern in clinical practice. Postbiotics have emerged as a promising option for managing it.

MATERIALS AND METHODS

We conducted a retrospective-prospective, 2-group, observational study to assess the impact of the postbiotic PostbiotiX-Restore, derived by Lactobacillus paracasei CNCM I-5220, on abemaciclib-induced diarrhea in patients with hormone receptor-positive HER2-negative breast cancer. The prospective population (Postbio group) received postbiotic during the first cycle of abemaciclib, while the retrospective one received standard care (Standard group). Diarrhea grading was defined according to the National Cancer Institute's Common Terminology Criteria for Adverse Events.

RESULTS

During the first cycle, diarrhea occurred in 78.9% of patients in the Standard cohort and 97.1% in the Postbio one, with most cases being G1-G2. Severe (G3) diarrhea was significantly less frequent in the Postbio group (0%) compared to the Standard one (7.9%; P = .029). Over the entire study period, while the grading difference was not statistically significant, G3 events were less frequent in the Postbio population (5.9%) than the Standard one (15.4%). Moreover, Postbio patients required fewer dose reductions due to diarrhea compared to the Standard group (P = .002). Notably, in the Postbio population, G1 and G2 events had short median durations (3 and 1 days, respectively) and, for the 2 patients experiencing G3 events during the second abemaciclib cycle (off postbiotic), diarrhea lasted only 1 day.

CONCLUSIONS

Our study demonstrates the effect of PostbiotiX-Restore in mitigating abemaciclib-induced diarrhea, resulting in reduced severity, fewer dose reductions, and shorter duration. Further exploration and validation in larger cohorts are needed.

Real-world use of multigene signatures in early breast cancer: differences to clinical trials

PURPOSE

In Italy, Lombardy was the first region to reimburse multigene assays (MGAs) for patients otherwise candidates for chemotherapy. This is a real-world experience of MGAs usage in six referral cancer centers in Lombardy.

METHODS

Among MGAs, Oncotype DX (RS) was used in 97% of cases. Consecutive patients tested with Oncotype DX from July 2020 to July 2022 were selected. The distribution of clinicopathologic features by RS groups (low RS: 0-25, high RS: 26-100) was assessed using chi-square and compared with those of the TAILORx and RxPONDER trials.

RESULTS

Out of 1,098 patients identified, 73% had low RS. Grade and Ki67 were associated with RS (p < 0.001). In patients with both G3 and Ki67 > 30%, 39% had low RS, while in patients with both G1 and Ki67 < 20%, 7% had high RS. The proportion of low RS in node-positive patients was similar to that in RxPONDER (82% vs 83%), while node-negative patients with low RS were significantly less than in TAILORx (66% vs 86%, p < 0.001). The distribution of Grade was different from registration trials, with more G3 and fewer G1 (38% and 3%) than in TAILORx (18% and 27%) and RxPONDER (10% and 24%) (p < 0.001). Patients ≤ 50 years were overrepresented in this series (41%) than in TAILORx and RxPONDER (31% and 24%, respectively) (p < 0.001) and, among them, 42% were node positive.

CONCLUSIONS

In this real-world series, Oncotype DX was the test almost exclusively used. Despite reimbursement being linked to pre-test chemotherapy recommendation, almost 3/4 patients resulted in the low-RS group. The significant proportion of node-positive patients ≤ 50 years tested indicates that oncologists considered Oncotype DX informative also in this population.

Cyclin-dependent kinase 2 (CDK2) inhibitors and others novel CDK inhibitors (CDKi) in breast cancer: clinical trials, current impact, and future directions

Aberrant cyclin-dependent kinase 2 (CDK2) activation has been identified as a main resistance mechanism to CDK4/6 inhibition in hormone-receptor positive (HR+) breast cancer. Additionally, consistent preclinical evidence states its crucial role in MYC and CCNE1 overexpressed cancer survival, such as triple-negative breast cancers (TNBC), thus representing an appealing and relatively unexplored target treatment opportunity. Despite emerging initial results of novel CDK2 inhibitors (CDK2i) activity, a comprehensive outcomes collection is currently absent from the scientific literature. We aim to provide an overview of ongoing clinical trials involving CDK2i in the context of metastatic breast cancer (mBC), either as monotherapy or in combination with other agents. The review extends beyond CDK2i to encompass novel emerging CDK4 inhibitors, combined CDK2/4/6 inhibitors, and the well-known pan-CDK inhibitors including those specifically directed at CDK2. Delving into the results, we critically appraise the observed clinical efficacy and offer valuable insights into their potential impact and future applications.

Fine-Tuning Adjuvant Endocrine Therapy for Early-Stage Breast Cancer: An Expert Consensus on Open Issues for Future Research

After decades of research, improving the efficacy of adjuvant endocrine therapy (ET) for early-stage breast cancer becomes increasingly difficult. Beyond technological breakthroughs and the availability of new classes of drugs, further improvement of adjuvant ET will require applying a rigorous research approach in poorly investigated areas. We critically discuss some key principles that should inform future research to improve ET efficacy, including identifying specific subgroups of patients who can benefit from escalating or de-escalating approaches, optimizing available and new treatment strategies for different clinical contexts, and dissecting the direct and indirect biological effects of therapeutic interventions. Four main issues regarding adjuvant ET were identified as relevant areas, where a better application of such principles can provide positive results in the near future: (i) tailoring the optimal duration of adjuvant ET, (ii) optimizing ovarian function suppression for premenopausal women, (iii) dissecting the biological effects of estrogen receptor manipulation, and (iv) refining the selection of patients to candidate for treatments escalation.

Denosumab improves trabecular bone score in relationship with decrease in fracture risk of women exposed to aromatase inhibitors

PURPOSE

Trabecular bone score (TBS) is a gray-level textural metric that has shown to correlate with risk of fractures in several forms of osteoporosis. The value of TBS in predicting fractures and the effects of bone-active drugs on TBS in aromatase inhibitors (AIs)-induced osteoporosis are still largely unknown. The primary objective of this retrospective study was to assess the effects of denosumab and bisphosphonates (BPs) on TBS and vertebral fractures (VFs) in women exposed to AIs.

METHODS

241 consecutive women (median age 58 years) with early breast cancer undergoing treatment with AIs were evaluated for TBS, bone mineral density (BMD) and morphometric VFs at baseline and after 18-24 months of follow-up. During the study period, 139 women (57.7%) received denosumab 60 mg every 6 months, 53 (22.0%) BPs, whereas 49 women (20.3%) were not treated with bone-active drugs.

RESULTS

Denosumab significantly increased TBS values (from 1.270 to 1.323; P < 0.001) accompanied by a significant decrease in risk of VFs (odds ratio 0.282; P = 0.021). During treatment with BPs, TBS did not significantly change (P = 0.849) and incidence of VFs was not significantly different from women untreated with bone-active drugs (P = 0.427). In the whole population, women with incident VFs showed higher decrease in TBS vs. non-fractured women (P = 0.003), without significant differences in changes of BMD at any skeletal site.

CONCLUSIONS

TBS variation predicts fracture risk in AIs treated women. Denosumab is effective to induce early increase of TBS and reduction in risk of VFs.

Unveiling the HER2-low phenomenon: exploring immunohistochemistry and gene expression to characterise HR-positive HER2-negative early breast cancer

PURPOSE

HER2-low breast cancer (BC) is a novel entity with relevant therapeutic implications, especially in hormone receptor (HR) positive BC. This study examines whether HER2 mRNA through the 21-gene assay, Oncotype DX (ODX), can refine the diagnosis of HER2-low and HER2-zero, obtained by immunohistochemistry (IHC).

METHODS

Between Jan 2021 and Jan 2023, 229 consecutive HR-positive HER2-negative early BC (T1-3 N0-1) have been characterised by IHC and ODX. HER2 status by IHC was either zero (IHC-0) or low (IHC-1 + and IHC-2 + /ISH-negative) while HER2-zero was further divided into HER2-null (IHC-0) and HER2-ultralow (IHC-1-10%). HER2 gene expression by ODX was negative if lower 10.7.

RESULTS

The distribution of HER2 IHC was as follows: 53.3% HER2-0, 29.25% HER2-1 + , and 17.5% HER2-2 + . The clinicopathological characteristics were similar in the three groups, with higher PgR-negative rate in HER2-zero (13.9% vs 3% vs 5%). The distribution of RS was homogeneous in the three groups with the median HER2 gene expression of 9.20 [IQR: 8.70-9.60]. HER2 gene expression gradually increased as the IHC score, with substantial overlap. After adjusting for confounders, HER2-1 + and HER2 2 + had a significant positive correlation between HER2 gene expression and IHC [OR 1.42, 95% CI 1.21 to 1.68, p < 0.001; OR 1.96, 95% CI 1.61 to 2.37, p < 0.001] compared to the HER2-zero group. HER2 gene expression did not differ between HER2-null and HER2-ultralow subgroups.

CONCLUSION

Due to the substantial overlap, the HER2 gene expression is unable to properly distinguish HER2-low and HER2-zero IHC whose accurate identification is critical in the context of HER2-negative BC.

The Impact of Different Patterns of Residual Disease on Long-Term Oncological Outcomes in Breast Cancer Patients Treated with Neo-Adjuvant Chemotherapy

BACKGROUNDS

The majority of breast cancer (BC) patients treated with neo-adjuvant chemotherapy (NAC) achieves a pathologic partial response with different patterns of residual disease. No clear correlation between these patterns and oncological results was described. Our aims were to define the predictive factors for different patterns of residual disease and compare the outcomes between the scattered versus the circumscribed pattern.

METHODS

We reviewed 219 postoperative surgical specimens. Patients were divided into two groups: scattered versus circumscribed. Disease-free survival (DFS), distant DFS (DDFS), and overall survival (OS) were analyzed.

RESULTS

The scattered and circumscribed patterns were assessed in 111 (50.7%) and 108 (49.3%) patients. Two independent predictive factors for the circumscribed pattern were identified: discontinuation of NAC cycles (p = 0.011), and tumor size post-NAC >18 mm (p = 0.022). No difference was observed in terms of DFS and DDFS. Patients with the scattered pattern exhibited a statistically significant better OS. Discontinuation of NAC cycles, tumor size >18 mm, triple-negative BC, and ypN+ were associated with increased recurrence and poorer survival.

CONCLUSIONS

Discontinuation of NAC cycles and tumor size are independent factors associated with patterns of residual disease. The scattered pattern presents better survival. Understanding the relationship between NAC, the residual pattern, and differences in survival outcomes offers the potential to optimize the therapeutic approaches.

Common Misconceptions about Diet and Breast Cancer: An Unclear Issue to Dispel

Breast cancer (BC) constitutes a prevalent health condition among women. Recent years have witnessed the identification of dietary proto-oncogenic factors that deserve attention. Besides the well-known role of alcohol and red and processed meat in BC development, the impact of other dietary components remains unclear. Our narrative review aims to explore the diet-BC relationship, focusing on sugar, dairy, and soy consumption. We conducted a PubMed literature search covering the last decade (2013-2023) and included 35 papers. We found limited evidence on the association between high sugar intake and BC incidence. On the other hand, dairy and soy consumption displayed a protective effect in the majority of the analyzed papers. However, a significant degree of heterogeneity was reported among the results. Menopausal status and the specific BC molecular subtypes were the main factors influencing the interpretation of the results. Exploring dietary factors and BC revealed inconsistencies: high glycemic index post-menopause may be a risk factor, while sugar-sweetened drinks and artificial sweeteners yielded conflicting results; fermented dairy showed potential benefits, non-fermented dairy presented inconsistent findings; soy impact on BC varied according to molecular subtype, with some studies suggesting a positive association in luminal-like BC. Hence, further investigation is crucial to obtain a uniform consensus on the diet-BC relationship.

Clinical Outcomes of HER2-Negative Metastatic Breast Cancer Patients in Italy in the Last Decade: Results of the GIM 13-AMBRA Study

GIM 13-AMBRA is a longitudinal cohort study aimed at describing therapeutic strategies and the relative outcome parameters in 939 HER2-ve MBC patients. Taxanes-based regimens, or taxanes + targeted agents, mainly Bevacizumab, were the preferred first choice in both Luminal (30.2%) and TNBC (33.3%) patients. The median PFS1 was 12.5 months (95% CI 16.79-19.64), without any significant difference according to subtypes, while the median Time to first Treatment Change (TTC1) was significantly lower in TNBC patients (7.7 months-95% CI 5.7-9.2) in comparison to Luminal A (13.2 months, 95% CI 11.7-15.1) and Luminal B patients (11.8 months, 95% CI 10.3-12.8). PFS2 was significantly shorter in TNBC patients (5.5 months, 95% CI 4.3-6.5 vs. Luminal A-9.4, 95% CI 8.1-10.7, and Luminal B-7.7 95% CI 6.8-8.2, F-Ratio 4.30, p = 0.014). TTC2 was significantly lower in patients with TNBC than in those with the other two subtypes. The median OS1 was 35.2 months (95% CI 30.8-37.4) for Luminal A patients, which was significantly higher than that for both Luminal B (28.9 months, 95% CI 26.2-31.2) and TNBC (18.5 months, 95% CI 16-20.1, F-ratio 7.44, p = 0.0006). The GIM 13-AMBRA study is one of the largest collections ever published in Italy and provides useful results in terms of time outcomes for first, second, and further lines of treatment in HER2- MBC patients.

Association of tumor-infiltrating lymphocytes with recurrence score in hormone receptor-positive/HER2-negative breast cancer: Analysis of four prospective studies

BACKGROUND

The clinical value of tumor infiltrating lymphocytes (TILs) in hormone receptor-positive (HR+)/HER2- breast cancer (BC) may be unearthed by focusing on more biologically aggressive tumors. Here we deepen and describe the correlation between RS and TILs, proposing an immuno-genomic model for HR+ /HER2- BC.

METHODS

We enrolled T1-T3, N0-N1 BC patients with available RS® and TILs in the context of four multicenter, prospective studies. RS® and TILs were considered as continuous and categorical variables. RS® was categorized into: 0-10 (low risk), 11-25 (intermediate risk) and 26-100 (high risk); TILs were categorized into: low TILs (0-10%), intermediate TILs (11-59%) and high TILs (60-100%).

RESULTS

811 patients were included. RS distribution was (n = 810): low risk 22.0%, intermediate risk 61.2%, high risk 16.8%. TIL distribution was (n = 455): low TILs 84.6%, intermediate TILs 13.6% and high TILs 1.8%. A significant, weak positive, linear correlation was found between continuous TILs and RS (Pearson coefficient=0.223, p < 0.001). When considering RS and TILs categories, tumors with intermediate/high TIL levels significantly enriched the high RS subgroup (p = 0.006). This was confirmed both within Luminal A and Luminal B cohorts. Among high-RS patients, 16.7% of Luminal A and 26.7% of Luminal B tumors had intermediate/high TILs.

CONCLUSIONS

We observed that RS® and TILs capture only slightly overlapping information on the biology of HR+ /HER2- tumor microenvironment. We demonstrated the feasibility of combining RS and TILs into a composite immuno-genomic model, which may serve the purpose of guiding and focalizing patient selection in the further development of immunotherapy strategies for Luminal-like disease.

Randomized, open-label, phase II, biomarker study of immune-mediated mechanism of action of neoadjuvant subcutaneous trastuzumab in patients with locally advanced, inflammatory, or early HER2-positive breast cancer-Immun-HER trial (GOIRC-01-2016)

BACKGROUND

It is possible to induce immunomodulation in HER2-positive breast cancer (BC) by modifying the route of administration of trastuzumab.

METHODS

In this multicenter randomized phase II trial, all enrolled patients (pts) with T2-T4d HER2-positive BC received 3 cycles of neoadjuvant treatment (NAT) with fluorouracil, epirubicin and cyclophosphamide every 3 weeks (q21), followed by docetaxel/pertuzumab plus intravenous trastuzumab (arm A) or, docetaxel/pertuzumab plus subcutaneous (SC) trastuzumab (arm B) q21x4 cycles. After surgical operation, each pt was treated with trastuzumab q21x14 cycles using the same SC or intravenous formulation of NAT. Primary endpoint was the proportion of subjects with high stromal tumor-infiltrating lymphocytes (sTILs) in postneoadjuvant residual disease (RD).

RESULTS

Sixty-three pts (31 (arm A) and 32 (arm B)) were enrolled. Pathological complete response was obtained by 20/31 pts (64.5%; 95% CI 45.4% to 80.1%) in arm A and 19/32 pts (59.4%; 95% CI 40.1% to 76.3%) in arm B. High sTILs were observed in 27% and 46% of postneoadjuvant residual tumors in arms A and B, respectively. CD8+ T cells increased significantly in RDs of both arms (p=0.014 and 0.002 for arm A and B, respectively), whereas a significant decline in the level of CD4+ FoxP3+ regulatory T cells was observed only in arm B (p=0.016). A significant upregulation of PD-1 on sTILs was found in RD of pts enrolled in arm B (p=0.012), while programmed death-ligand 1 (PD-L1) was significantly overexpressed in residual tumors of arm A (p=0.02). A strong negative correlation was reported in arm B between expression of PD-L1 on pretreatment sTILs and CD3 expression on sTILs in RD (τ: -0.73). Grade≥3 AE incidence rates were similar between the two arms.

CONCLUSIONS

SC trastuzumab induced relevant sTILs enrichment, with favorable variations of immune parameters in HER2-positive BC pts with RD after NAT. Novel immunotherapy strategies should be tested to achieve SC-specific, antitumor immune response.

TRIAL REGISTRATION NUMBER

NCT03144947, and EudraCT number: 2016-000435-41.

Working tables on Hormone Receptor positive (HR+), Human Epidermal growth factor Receptor 2 negative (HER2-) early stage breast cancer: Defining high risk of recurrence

Hormone-receptor positive (HR+), Human-Epidermal-growth Factor negative (HER2-) breast cancer, including the Luminal A and the Luminal B subtypes, is the most common in women diagnosed with early-stage BC. Despite the advances in screening, surgery and therapies, recurrence still occurs. Therefore, it is important to identify early those factors that significantly impact the recurrence risk. Based on current evidence and their professional expertise, a Panel of oncologists discussed the definition of high risk of recurrence in early breast cancer. Histological grade, nodal involvement, genomic score, histological grade, tumor size, and Ki-67 proliferation index were rated as the most important factors to define the high risk in patients with early breast cancer. All these factors should be considered comprehensively to tailor the choice of treatment to the peculiar characteristics of each patient.

A cost-consequence analysis of adding pertuzumab to the neoadjuvant combination therapy in HER2-positive high-risk early breast cancer in Italy

INTRODUCTION

Clinical trials confirmed the beneficial effects of adding pertuzumab (P) to the combination of trastuzumab-chemotherapy (TC) in the (neo)adjuvant setting of high-risk HER2-positive early breast cancer (HER2+BC). We evaluated the clinical, economic and societal impact of adding pertuzumab to neoadjuvant TC combination (TPC) in Italy.

METHODS

A cost-consequence analysis comparing TPC vs. TC was performed developing a cohort-based multi-state Markov model to estimate the clinical, societal and economic impact of the neoadjuvant therapy of TPC versus TC in HER2+BC at high-risk of recurrence. The model works on a cycle length of 1 month and 5-years-time horizon. Literature review-based data were used to populate the model. The following clinical and economic outcomes were estimated: cumulative incidence of loco-regional/distant recurrences, life of years and QALY and both direct and indirect costs (€). Finally, sensitivity analyses were performed.

RESULTS

TPC was associated with a 75,630 € saved of direct costs. Specifically, it was associated with an initial increase of treatment costs (+4.8%) followed by reduction of recurrence management cost (-20.4%). TPC was also associated with an indirect cost reduction of 1.40%, as well as decreased incidence of distant recurrence (-20.14%), days of work lost (-1.53%) and days lived with disability (-0.50%). Furthermore, TPC reported 10,47 QALY gained (+2.77%) compared to TC. The probability to achieve the pathological complete response (pCR) was the parameter that mostly affected the results in the sensitivity analysis.

CONCLUSION

Our findings suggested that TPC combination could be a cost-saving option in patients with HER2+BC at high-risk of recurrence.

Risk-Based Therapeutic Strategies for HER2-Positive Early Breast Cancer: A Consensus Paper

Breast cancer represents the most commonly diagnosed neoplasm worldwide and the HER2-positive subtype accounts for nearly 1 in 5 breast cancers. The majority of patients with breast cancer present with an early-stage disease upon diagnosis, which is thus susceptible to virtually curative treatment strategies. For a stage, I T1a/b N0 HER2-positive disease, upfront surgery followed by adjuvant therapy is the preferred approach. However, there is some uncertainty regarding the appropriate management of stage cT1c cN0, as both the neoadjuvant approach and upfront surgery have been proven to be feasible therapeutic options. The aim of this Delphi consensus was to define the best strategies for the treatment of early HER2-positive breast cancer. This work may help clinicians in the management of early HER2-positive breast cancer.

A Prognostic Model Based on Residual Cancer Burden and Tumor-Infiltrating Lymphocytes on Residual Disease after Neoadjuvant Therapy in HER2+ Breast Cancer

PURPOSE

We aim to evaluate the prognostic significance of tumor-infiltrating lymphocyte on residual disease (RD-TIL) in HER2+ patients with breast cancer who failed to achieve pathologic complete response (pCR) after anti-HER2+ chemotherapy (CT)-based neoadjuvant treatment (NAT). We assessed the feasibility of combining the prognostic information provided by residual cancer burden (RCB) and RD-TILs into a composite score (RCB+TIL).

EXPERIMENTAL DESIGN

HER2+ patients with breast cancer treated with CT+anti-HER2-based NAT at three institutions were retrospectively included. RCB and TIL levels were evaluated on hematoxylin and eosin-stained slides from surgical samples according to available recommendations. Overall survival (OS) was used as an outcome measure.

RESULTS

A total of 295 patients were included, of whom 195 had RD. RCB was significantly associated with OS. Higher RD-TILs were significantly associated with poorer OS as compared with lower RD-TILs (15% cutoff). In multivariate analysis, both RCB and RD-TIL maintained their independent prognostic value. A combined score, RCB+TIL, was calculated from the estimated coefficient of RD-TILs and the RCB index in a bivariate logistic model for OS. The RCB+TIL score was significantly associated with OS. The C-index for OS of the RCB+TIL score was numerically higher than that of RCB and significantly higher than that of RD-TILs.

CONCLUSIONS

We have reported an independent prognostic impact of RD-TILs after anti-HER2+CT NAT, which might underlie an imbalance of the RD microenvironment towards immunosuppressive features. We provided a new composite prognostic score based on RCB+TIL, which was significantly associated with OS and proved to be more informative than the isolated evaluation of RCB and RD-TILs.

Platinum-based chemotherapy and PARP inhibitors for patients with a germline BRCA pathogenic variant and advanced breast cancer (LATER-BC): retrospective multicentric analysis of post-progression treatments

INTRODUCTION

Patients with breast cancer (BC) harbouring a germinal BRCA pathogenic variant (gBRCA-PV) may have an enhanced sensitivity to platinum-based chemotherapy (PBC) and PARP inhibitors (PARPi). As reported in ovarian cancer, however, sensitivity and resistance to these treatments could partially overlap. In patients with a gBRCA-PV and advanced BC (aBC), it remains unclear whether prior exposure to PARPi/PBC affects tumour response to subsequent PBC/PARPi, respectively.

METHODS

We conducted a retrospective, multicentric study to investigate the clinical benefit of post-PBC PARPi and vice versa in patients with a gBRCA-PV and aBC. Patients included had received (neo)adjuvant PBC and then PARPi in advanced setting (group 1), PBC followed by PARPi (group 2) or PARPi followed by PBC (group 3), both in advanced setting. We reported median progression-free survival (mPFS) and disease control rate (DCR) in each group.

RESULTS

A total of 67 patients from six centres were included. PARPi-mPFS in advanced setting was 6.1 months in patients in group 1 (N = 12), while PARPi-DCR was 67%. In group 2 (N = 36), PARPi-mPFS was 3.4 months and PARPi-DCR was 64%. Age < 65 years and platinum-free interval (PFI) > 6 months were associated with longer PARPi-PFS; previous PBC-PFS > 6 months and PBC in first to second line were associated with longer PARPi-DCR. Patients in group 3 (N = 21) reported a PBC-mPFS of 1.8 months and a PBC-DCR of 14%. PARPi-PFS ≥ 9 months and PARPi-FI ≥ 6 months were associated with better PBC-DCR.

CONCLUSIONS

Sensitivity and resistance to PARPi and PBC partially overlap in patients with a gBRCA-PV and aBC. Evidence of PARPi activity emerged in patients who progressed on previous PBC.

Sentinel lymph node biopsy versus axillary lymph node dissection in breast cancer patients undergoing mastectomy with one to two metastatic sentinel lymph nodes: sub-analysis of the SINODAR-ONE multicentre randomized clinical trial and reopening of enrolment

BACKGROUND

The initial results of the SINODAR-ONE randomized clinical trial reported that patients with T1-2 breast cancer and one to two macrometastatic sentinel lymph nodes treated with breast-conserving surgery, sentinel lymph node biopsy only, and adjuvant therapy did not present worse 3-year survival, regional recurrence, or distant recurrence rates compared with those treated with axillary lymph node dissection. To extend the recommendation of axillary lymph node dissection omission even in patients treated with mastectomy, a sub-analysis of the SINODAR-ONE trial is presented here.

METHODS

Patients with T1-2 breast cancer and no more than two metastatic sentinel lymph nodes undergoing mastectomy were analysed. After sentinel lymph node biopsy, patients were randomly assigned to receive either axillary lymph node dissection followed by adjuvant treatment (standard arm) or adjuvant treatment alone (experimental arm). The primary endpoint was overall survival. The secondary endpoint was recurrence-free survival.

RESULTS

A total of 218 patients were treated with mastectomy; 111 were randomly assigned to the axillary lymph node dissection group and 107 to the sentinel lymph node biopsy-only group. At a median follow-up of 33.0 months, there were three deaths (two deaths in the axillary lymph node dissection group and one death in the sentinel lymph node biopsy-only group). There were five recurrences in each treatment arm. No axillary lymph node recurrence was observed. The 5-year overall survival rates were 97.8 and 98.7 per cent in the axillary lymph node dissection treatment arm and the sentinel lymph node biopsy-only treatment arm, respectively (P = 0.597). The 5-year recurrence-free survival rates were 95.7 and 94.1 per cent in the axillary lymph node dissection treatment arm and the sentinel lymph node biopsy treatment arm, respectively (P = 0.821).

CONCLUSION

In patients with T1-2 breast cancer and one to two macrometastatic sentinel lymph nodes treated with mastectomy, the overall survival and recurrence-free survival rates of patients treated with sentinel lymph node biopsy only were not inferior to those treated with axillary lymph node dissection. To strengthen the conclusion of the trial, the enrolment of patients treated with mastectomy was reopened as a single-arm experimental study.

REGISTRATION NUMBER

NCT05160324 (http://www.clinicaltrials.gov).

Opportunities and Challenges of Synthetic Data Generation in Oncology

Widespread interest in artificial intelligence (AI) in health care has focused mainly on deductive systems that analyze available real-world data to discover patterns not otherwise visible. Generative adversarial network, a new type of inductive AI, has recently evolved to generate high-fidelity virtual synthetic data (SD) trained on relatively limited real-world information. The AI system is fed with a collection of real data, and it learns to generate new augmented data while maintaining the general characteristics of the original data set. The use of SD to enhance clinical research and protect patient privacy has drawn a lot of interest in medicine and in the complex field of oncology. This article summarizes the main characteristics of this innovative technology and critically discusses how it can be used to accelerate data access for secondary purposes, providing an overview of the opportunities and challenges of SD generation for clinical cancer research and health care.

Unlocking the Potential of Circulating miRNAs in the Breast Cancer Neoadjuvant Setting: A Systematic Review and Meta-Analysis

The potential role of circulating microRNAs (miRNAs) as biomarkers in breast cancer (BC) management has been widely reported. However, the numerous discrepancies between studies in this regard hinders the implementation of circulating miRNAs in routine clinical practice. In the context of BC patients undergoing neoadjuvant chemotherapy (NAC), the possibility of predicting NAC response may lead to prognostic improvements by individualizing post-neoadjuvant therapy. In this context, the present meta-analysis aims to clarify circulating miRNAs' predictive role with respect to NAC response among BC patients. We conducted a comprehensive literature search on five medical databases until 16 February 2023. We pooled the effect sizes of each study by applying a random-effects model. Cochran's Q test (p-level of significance set at 0.05) scores and I² values were assessed to determine between-study heterogeneity. The PROBAST (Prediction Model Risk of Bias Assessment Tool) tool was used to evaluate the selected studies' risk of bias. Overall, our findings support the hypothesis that circulating miRNAs, specifically miR-21-5p and miR-155-5p, may act as predictive biomarkers in the neoadjuvant setting among BC patients. However, due to the limited number of studies included in this meta-analysis and the high degrees of clinical and statistical heterogeneity, further research is required to confirm the predictive power of circulating miR-21-5p and miR-155-5p.

The Role of Female Reproductive Hormones in the Association between Migraine and Breast Cancer: An Unanswered Question

Accumulating epidemiological studies have investigated a possible interconnection between migraine (Mi) and breast cancer (BC) because of the strong link between these diseases and female reproductive hormones. This review aims to consolidate findings from epidemiological studies and explore biologically plausible hypothetical mechanisms related to hormonal pathways. Current evidence suggests a protective role of Mi in BC development, particularly in case-control studies but not in cohort ones. The inconsistency among studies may be due to several reasons, including diagnostic criteria for Mi and the age gap between the development of these two diseases. Furthermore, recent research has challenged the concept of a net beneficial effect of Mi on BC, suggesting a more complex relationship between the two conditions. Many polymorphisms/mutations in hormone-related pathways are involved in at least one of the two conditions. The most promising evidence has emerged for a specific alteration in the estrogen receptor 1 gene (rs2228480). However, the possible specific mutation or polymorphism involved in this association has not yet been identified. Further studies with robust methodologies are needed to validate the protective role of Mi in BC and fully elucidate the precise nature of this causal relationship.

Hope and Hype around Immunotherapy in Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) holds a poor prognosis compared to other breast cancer subtypes, and the development of new effective treatment strategies is an unmet medical need. TNBC has traditionally been considered not amenable to treatment with targeted agents due to a lack of actionable targets. Therefore, chemotherapy has remained the mainstay of systemic treatment for many decades. The advent of immunotherapy raised very hopeful expectations in TNBC, possibly due to higher levels of tumor-infiltrating lymphocytes, PD-L1 expression and tumor mutational burden compared to other breast cancer subtypes, that predict an effective anti-tumor immune-engagement. The results of clinical trials testing immunotherapy in TNBC led to the approval of the combination of immune checkpoint inhibitors and chemotherapy in both early and advanced settings. However, some open questions about the use of immunotherapy in TNBC still exist. These include a deeper understanding of the heterogeneity of the disease, identification of reliable predictive biomarkers of response, determination of the most appropriate chemotherapy backbone and appropriate management of potential long-term immune-related adverse events. In this review we aim to examine the available evidence on the use of immunotherapy strategies in both early and advanced TNBC, to critically discuss some of the limitations encountered in clinical research and to summarize data on novel promising immunotherapeutic strategies beyond PD-(L)1 blockade that have been investigated in the most recent trials.

Pandemic Phase-Adjusted Analysis of COVID-19 Outcomes Reveals Reduced Intrinsic Vulnerability and Substantial Vaccine Protection From Severe Acute Respiratory Syndrome Coronavirus 2 in Patients With Breast Cancer

PURPOSE

Although representing the majority of newly diagnosed cancers, patients with breast cancer appear less vulnerable to COVID-19 mortality compared with other malignancies. In the absence of patients on active cancer therapy included in vaccination trials, a contemporary real-world evaluation of outcomes during the various pandemic phases, as well as of the impact of vaccination, is needed to better inform clinical practice.

METHODS

We compared COVID-19 morbidity and mortality among patients with breast cancer across prevaccination (February 27, 2020-November 30, 2020), Alpha-Delta (December 1, 2020-December 14, 2021), and Omicron (December 15, 2021-January 31, 2022) phases using OnCovid registry participants (ClinicalTrials.gov identifier: NCT04393974). Twenty-eight-day case fatality rate (CFR28) and COVID-19 severity were compared in unvaccinated versus double-dosed/boosted patients (vaccinated) with inverse probability of treatment weighting models adjusted for country of origin, age, number of comorbidities, tumor stage, and receipt of systemic anticancer therapy within 1 month of COVID-19 diagnosis.

RESULTS

By the data lock of February 4, 2022, the registry counted 613 eligible patients with breast cancer: 60.1% (n = 312) hormone receptor-positive, 25.2% (n = 131) human epidermal growth factor receptor 2-positive, and 14.6% (n = 76) triple-negative. The majority (61%; n = 374) had localized/locally advanced disease. Median age was 62 years (interquartile range, 51-74 years). A total of 193 patients (31.5%) presented ≥ 2 comorbidities and 69% (n = 330) were never smokers. In total, 392 (63.9%), 164 (26.8%), and 57 (9.3%) were diagnosed during the prevaccination, Alpha-Delta, and Omicron phases, respectively. Analysis of CFR28 demonstrates comparable estimates of mortality across the three pandemic phases (13.9%, 12.2%, 5.3%, respectively; P = .182). Nevertheless, a significant improvement in outcome measures of COVID-19 severity across the three pandemic time periods was observed. Importantly, when reported separately, unvaccinated patients from the Alpha-Delta and Omicron phases achieved comparable outcomes to those from the prevaccination phase. Of 566 patients eligible for the vaccination analysis, 72 (12.7%) were fully vaccinated and 494 (87.3%) were unvaccinated. We confirmed with inverse probability of treatment weighting multivariable analysis and following a clustered robust correction for participating center that vaccinated patients achieved improved CFR28 (odds ratio [OR], 0.19; 95% CI, 0.09 to 0.40), hospitalization (OR, 0.28; 95% CI, 0.11 to 0.69), COVID-19 complications (OR, 0.16; 95% CI, 0.06 to 0.45), and reduced requirement of COVID-19-specific therapy (OR, 0.24; 95% CI, 0.09 to 0.63) and oxygen therapy (OR, 0.24; 95% CI, 0.09 to 0.67) compared with unvaccinated controls.

CONCLUSION

Our findings highlight a consistent reduction of COVID-19 severity in patients with breast cancer during the Omicron outbreak in Europe. We also demonstrate that even in this population, a complete severe acute respiratory syndrome coronavirus 2 vaccination course is a strong determinant of improved morbidity and mortality from COVID-19.

Hereditary Cancer Syndromes: A Comprehensive Review with a Visual Tool

Hereditary cancer syndromes account for nearly 10% of cancers even though they are often underdiagnosed. Finding a pathogenic gene variant could have dramatic implications in terms of pharmacologic treatments, tailored preventive programs, and familiar cascade testing. However, diagnosing a hereditary cancer syndrome could be challenging because of a lack of validated testing criteria or because of their suboptimal performance. In addition, many clinicians are not sufficiently well trained to identify and select patients that could benefit from a genetic test. Herein, we searched the available literature to comprehensively review and categorize hereditary cancer syndromes affecting adults with the aim of helping clinicians in their daily clinical practice through a visual tool.

Prognostic significance of HER2-low status in HR-positive/HER2-negative advanced breast cancer treated with CDK4/6 inhibitors

Whether Human Epidermal growth factor Receptor 2 (HER2)-low status has prognostic significance in HR + /HER2- advanced Breast Cancer (aBC) patients treated with first-line Endocrine Therapy plus CDK 4/6 inhibitors remains unclear. In 428 patients evaluated, HER2-low status was independently associated with significantly worse PFS and OS when compared with HER2-0 status. Based on our findings, HER2-low status could become a new prognostic biomarker in this clinical setting.

A phase II study of pembrolizumab plus carboplatin in BRCA-related metastatic breast cancer (PEMBRACA)

BACKGROUND

BRCA1/2-related metastatic breast cancers (mBC) are sensitive to DNA-damage agents and show high tumor-infiltrated lymphocytes. We hypothesized that the association between pembrolizumab and carboplatin could be active in BRCA-related mBC.

PATIENTS AND METHODS

In this phase II Simon's design multicenter single-arm study, BRCA1/2-related mBC patients received carboplatin at area under the curve 6 every 3 weeks for six courses associated with 200 mg pembrolizumab every 3 weeks until disease progression or unacceptable toxicity. The primary aim at first stage was overall response rate (ORR) ≥70%. Disease control rate (DCR), time to progression (TTP), duration of response (DOR), and overall survival (OS) were the secondary aims.

RESULTS

Among 22 patients enrolled at the first stage, 5 BRCA1 and 17 BRCA2, 16 (76%) were luminal tumors and 6 (24%) triple-negative BC (TNBC). In 21 patients, ORR and DCR were 43% and 76% (47% and 87% in luminal, 33% and 50% in TNBC), respectively. TTP was 7.1 months, DOR was 6.3 months, and median OS was not reached. Grade ≥3 adverse events (AEs) or serious AEs occurred in 5/22 patients (22.7%). Since the primary aim was not met, the study was terminated at the first stage.

CONCLUSIONS

Although the primary aim was not reached, data on efficacy and safety of pembrolizumab plus carboplatin in first-line visceral disease BRCA-related luminal mBC were provided and they need to be further investigated.

Clinical Review on the Management of Breast Cancer Visceral Crisis

Visceral crisis is a life-threatening clinical condition requiring urgent treatment and accounts for 10-15% of new advanced breast cancer diagnoses, mainly hormone receptor-positive/human epidermal growth factor 2 negative. As its clinical definition is an open topic with nebulous criteria and much room for subjective interpretation, it poses a challenge for daily clinical practice. International guidelines recommend combined chemotherapy as first-line treatment for patients with visceral crisis, but with modest results and a very poor prognosis. Visceral crisis has always been a common exclusion criterion in breast cancer trials, and the available evidence mainly comes from limited retrospective studies which are not sufficient to draw solid conclusions. The outstanding efficacy of innovative drugs, such as CDK4/6 inhibitors, questions the role of chemotherapy in this setting. In the lack of clinical reviews, we aim to critically discuss the management of visceral crisis, advocating future treatment perspectives for this challenging condition.

SARS-CoV-2 omicron (B.1.1.529)-related COVID-19 sequelae in vaccinated and unvaccinated patients with cancer: results from the OnCovid registry

BACKGROUND

COVID-19 sequelae can affect about 15% of patients with cancer who survive the acute phase of SARS-CoV-2 infection and can substantially impair their survival and continuity of oncological care. We aimed to investigate whether previous immunisation affects long-term sequelae in the context of evolving variants of concern of SARS-CoV-2.

METHODS

OnCovid is an active registry that includes patients aged 18 years or older from 37 institutions across Belgium, France, Germany, Italy, Spain, and the UK with a laboratory-confirmed diagnosis of COVID-19 and a history of solid or haematological malignancy, either active or in remission, followed up from COVID-19 diagnosis until death. We evaluated the prevalence of COVID-19 sequelae in patients who survived COVID-19 and underwent a formal clinical reassessment, categorising infection according to the date of diagnosis as the omicron (B.1.1.529) phase from Dec 15, 2021, to Jan 31, 2022; the alpha (B.1.1.7)-delta (B.1.617.2) phase from Dec 1, 2020, to Dec 14, 2021; and the pre-vaccination phase from Feb 27 to Nov 30, 2020. The prevalence of overall COVID-19 sequelae was compared according to SARS-CoV-2 immunisation status and in relation to post-COVID-19 survival and resumption of systemic anticancer therapy. This study is registered with ClinicalTrials.gov, NCT04393974.

FINDINGS

At the follow-up update on June 20, 2022, 1909 eligible patients, evaluated after a median of 39 days (IQR 24-68) from COVID-19 diagnosis, were included (964 [50·7%] of 1902 patients with sex data were female and 938 [49·3%] were male). Overall, 317 (16·6%; 95% CI 14·8-18·5) of 1909 patients had at least one sequela from COVID-19 at the first oncological reassessment. The prevalence of COVID-19 sequelae was highest in the pre-vaccination phase (191 [19·1%; 95% CI 16·4-22·0] of 1000 patients). The prevalence was similar in the alpha-delta phase (110 [16·8%; 13·8-20·3] of 653 patients, p=0·24), but significantly lower in the omicron phase (16 [6·2%; 3·5-10·2] of 256 patients, p<0·0001). In the alpha-delta phase, 84 (18·3%; 95% CI 14·6-22·7) of 458 unvaccinated patients and three (9·4%; 1·9-27·3) of 32 unvaccinated patients in the omicron phase had sequelae. Patients who received a booster and those who received two vaccine doses had a significantly lower prevalence of overall COVID-19 sequelae than unvaccinated or partially vaccinated patients (ten [7·4%; 95% CI 3·5-13·5] of 136 boosted patients, 18 [9·8%; 5·8-15·5] of 183 patients who had two vaccine doses vs 277 [18·5%; 16·5-20·9] of 1489 unvaccinated patients, p=0·0001), respiratory sequelae (six [4·4%; 1·6-9·6], 11 [6·0%; 3·0-10·7] vs 148 [9·9%; 8·4-11·6], p=0·030), and prolonged fatigue (three [2·2%; 0·1-6·4], ten [5·4%; 2·6-10·0] vs 115 [7·7%; 6·3-9·3], p=0·037).

INTERPRETATION

Unvaccinated patients with cancer remain highly vulnerable to COVID-19 sequelae irrespective of viral strain. This study confirms the role of previous SARS-CoV-2 immunisation as an effective measure to protect patients from COVID-19 sequelae, disruption of therapy, and ensuing mortality.

FUNDING

UK National Institute for Health and Care Research Imperial Biomedical Research Centre and the Cancer Treatment and Research Trust.

Abstract P6-08-01: A cost-consequence analysis of pertuzumab in the neoadjuvant treatment of high-risk HER2+ Early-Stage Breast Cancer (EBC): health-economic considerations for drug availability in Italy

Introduction: Neoadjuvant pertuzumab+trastuzumab+chemotherapy (TPC) combo is a well established treatment for HER2+ high-risk (EBC) as recommended by International and National guidelines. However, notwithstanding EMA approval, in some European countries (i.e Italy and France) pertuzumab drug-access is prevented by the NHS decision not to reimburse the drug in a value-driven sustainability balance. This study aims to estimate the cost and consequences of TPC vs. the same combo w/o pertuzumab (TC) in the neaodjuvant treatment of high-risk HER2+ eBC to better understand the value of TPC regimen.

Methods: With a Markov model, we simulated the costs and consequences associated to TPC or TC neoadjuvant treatments, using 5 years time horizon and Italian Lombardy region Health System point of view. The model includes nine health states: Neoadjuvant treatment; Surgery; Invasive disease-free Survival (IDFS) with pathological complete response (pCR), IDFS with residual disease (RD), non-metastatic recurrence, remission, first-line treatment and subsequent-lines for metastatic cancer, and death. Transition probabilities and utilities were derived from relevant clinical trials and literature. For each neoadjuvant treatment, the model estimates: direct (drug, administration, hospitalization, disease management), indirect (patients’ loss of productivity), total costs and different outcomes, as cumulative incidence of metastatic recurrence, days of work lost, days with activity impairment, IDFS life years, and quality adjusted life years (QALY). Costs and outcomes were estimated per 100-treated patients. An alternative scenario analysis with a 10-year time horizon and a deterministic sensitivity analysis was performed to assess the impact of model time horizon and parameters value.

Results: The estimated costs and outcomes for TPC and TC are reported in Table 1. TPC produces a total direct cost reduction of €75,630 per 100-treated patients, a small increase of TPC neoadjuvant treatment costs (+4.8%) is offset by the lower cost of metastatic treatment and management (-20.4%). Considering also the indirect costs, TPC is associated to a cost reduction of €124,956 per 100-treated patients. The cost saving is associated to a reduction of 5-year cumulative incidence metastatic recurrence (8.32% vs 10.42%, -20.14%), a reduction of days of work loss (-548 days) and days with activity impairment (-283 days) and a 10.5 QALY gained per 100-treated patients. Using a 10-year time horizon, the value of TPC compared to TC increases. Probabilities of pCR with TPC and TC were the parameter with the higher impact on model results.

Conclusion: Use of TC instead of TPC in high-risk HER2+ EBC derives a marginal savings (4.8%) according to the first year of our cost-consequence analysis. However, this negligible savings comes with the need for a heavily and long-lasting adjuvant cytotoxic therapy escalation because of a lower clinical activity of TC vs TPC. Moreover, according to medium-term cost-consequence analysis (5 years) the early negligible savings is overwhelmed by the subsequent increase in costs for the patients’ management, because of the lower clinical efficacy of TC vs. TPC. In Italy, the lack of pertuzumab in the neoadjuvant setting of high-risk HER2+ eBC is questionable; our results support the opportunity to reconsider the pertuzumab availability in Italy and reduce inequalities within Europe.

Cost and consequences of neoadjuvant treatments for high-risk HER2-Positive Early-Stage Breast Cancer: trastuzuamb+pertuzumab+chemotheraphy (TPC) vs trastuzumab+chemotheraphy (TC) IDFS, Invasive disease-free Survival; QALY, quality adjusted life years.

Citation Format: Alberto Zambelli, Marina Elena Cazzaniga, Nicla La Verde, Elisabetta Munzone, Ippazio Cosimo Antonazzo, Lorenzo Giovanni Mantovani, Anna Mancuso, Daniele G. Generali, Paolo Angelo Cortesi. A cost-consequence analysis of pertuzumab in the neoadjuvant treatment of high-risk HER2+ Early-Stage Breast Cancer (EBC): health-economic considerations for drug availability in Italy [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P6-08-01.

Abstract HER2-02: HER2-02 HER2-Low Status is Associated with Worse Clinical Outcomes in Hormone Receptor-Positive, HER2-Negative Advanced Breast Cancer Patients Treated With First-Line Cyclin-Dependent Kinase 4/6 Inhibitors Plus Endocrine Therapy

Introduction: Cyclin-dependent kinase 4/6 inhibitors (CDK4/6i) in combination with endocrine therapy (ET) are the standard first-line treatment for patients with hormone receptor-positive, human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer (HR+/HER2- aBC). HER2-low BC, which is defined by an IHC score for HER2 of 1+ or 2+ with negative ISH assay, accounts for more than half of all HR+/HER2- aBC cases, and it is associated with remarkable clinical benefit from the novel anti-HER2 antibody drug conjugate (ADC) trastuzumab-deruxtecan. Evidence on the prognostic impact of HER2-low status is controversial in both limited-stage and advanced BC. Here, we sought to investigate the possible prognostic relevance of HER2-low status in a population of aBC patients treated with CDK4/6i plus ET. Methods: We conducted a retrospective-prospective study in six Italian Cancer Centers to investigate the impact of HER2 status (low vs. 0) on the progression-free survival (PFS) and overall survival (OS) of consecutive HR+/HER2- aBC patients treated with CDK4/6i plus ET (aromatase inhibitors or fulvestrant) as a first-line therapy. In the main study analysis, we considered HER2 status in the last tumor assessment (i.e., primary tumor, or, when available, a metastatic lesion). We also performed a subgroup analysis including only patients with HER2 status evaluation in a metastatic lesion collected before CDK4/6i plus ET therapy initiation. The association between HER2 status (low vs. 0) and PFS or OS was evaluated using log-rank test and Cox regression modeling. Results: We evaluated 767 consecutive HR+/HER2- aBC patients treated with CDK4/6i plus ET between January 2017 and January 2022. Of these, 436 patients (56.8%) received CDK4/6i plus ET as a first-line therapy, and they were included in this analysis. Median age was 63 years (range 27-87), and 362 patients (83.0%) were postmenopausal. The majority of patients were treated with palbociclib (68.3%), while 91 (20.9%) and 47 (10.8%) patients received ribociclib and abemaciclib, respectively. Regarding HER2 status, 269 (62.9%) patients had HER2-low tumors, while 159 (37.1%) patients had HER2-0 neoplasms. HER2-low status was associated with significantly lower PFS when compared to HER2-0 status [median PFS (mPFS) 23.6 vs. 32.3 months, respectively; p=0.014]. HER2-low status was also associated with significantly worse OS (mOS 48.7 vs 58.3 months, respectively; p=0.025). These results were confirmed in multivariable models adjusting the impact of HER2 status for clinically-relevant covariates, namely estrogen receptor status, Ki-67, age, number of metastatic sites, presence of liver metastases, disease free interval, ECOG Performance Status. In this analysis, HER2-low status, compared with HER2-0 status, was independently associated with worse PFS [adjusted Hazard Ratio (aHR): 1.62; 95% confidence interval (CI): 1.17-2.24; p&lt; 0.01] and OS (aHR: 1.74; 95% CI: 1.09-2.76; p=0.019). Subgroup analysis conducted in the subset of 256 patients with available metastatic tumor samples collected before CDK4/6i plus ET initiation confirmed that HER2-low status (n=157), when compared to HER2-0 status (n=99), was independently associated with worse PFS (mPFS 24.5 vs 35.2 months, p=0.01; aHR 2.07; 95% CI: 1.28-3.34, p&lt; 0.01) and worse OS (mPFS 48.7 vs 72.3 months, p=0.027; aHR 3.12; 95% CI 1.44-6.77, p&lt; 0.01). Conclusions: This multicenter Italian study revealed that HER2-low status has independent, negative prognostic value in patients with HR+/HER2- aBC treated with CDK4/6i plus ET in the first-line setting. Our results suggest that HER2-low status might be associated with different clinical benefit from standard anticancer therapies in specific clinical settings. The definition of treatment algorithms also taking into account HER2 status is a clinical priority in patients with HR+/HER2- aBC.

Citation Format: Emma Zattarin, Caterina Sposetti, Rita Leporati, Luigi Mariani, Alice Menichetti, Chiara Corti, Chiara Benvenuti, Giovanni Fucà, Riccardo Lobefaro, Francesca Ligorio, Daniele Presti, Leonardo Provenzano, Andrea Vingiani, Gaia Griguolo, Marianna Sirico, Ottavia Bernocchi, Antonio Marra, Paola Zagami, Elisa Agostinetto, Flavia Jacobs, Pierluigi Di Mauro, Andrea Esposito, Carlo Alberto Giorgi, Luca Lalli, Laura Boldrini, Pier Paolo Maria Berton Giachetti, Ambra Carnevale Schianca, Valentina Guarneri, Rebecca Pedersini, Agnese Losurdo, Alberto Zambelli, Daniele Giulio Generali, Giuseppe Curigliano, Giancarlo Pruneri, Filippo de Braud, Maria Vittoria Dieci, Claudio Vernieri. HER2-02 HER2-Low Status is Associated with Worse Clinical Outcomes in Hormone Receptor-Positive, HER2-Negative Advanced Breast Cancer Patients Treated With First-Line Cyclin-Dependent Kinase 4/6 Inhibitors Plus Endocrine Therapy [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr HER2-02.

Optimizing choices and sequences in the diagnostic-therapeutic landscape of advanced triple-negative breast cancer: An Italian consensus paper and critical review

Triple-negative (TN) metastatic breast cancer (mBC) represents the most challenging scenario withing mBC framework, and it has been only slightly affected by the tremendous advancements in terms of drug availability and survival prolongation we have witnessed in the last years for advanced disease. However, although chemotherapy still represents the mainstay of TN mBC management, in the past years, several novel effective agents have been developed and made available in the clinical practice setting. Within this framework, a panel composed of a scientific board of 17 internationally recognized breast oncologists and 42 oncologists working within local spoke centers, addressed 26 high-priority statements, including grey areas, regarding the management of TN mBC. A structured methodology based on a modified Delphi approach to administer the survey and the Nominal Group Technique to capture perceptions and preferences on the management of TN mBC within the Italian Oncology community were adopted. The Panel produced a set of prioritized considerations/consensus statements reflecting the Panel position on diagnostic and staging approach, first-line and second-line treatments of PD-L1-positive/germline BRCA (gBRCA) wild-type, PD-L1-positive/gBRCA mutated, PD-L1-negative/gBRCA wild-type and PD-L1-negative/gBRCA mutated TN mBC. The Panel critically and comprehensively discussed the most relevant and/or unexpected results and put forward possible interpretations for statements not reaching the consensus threshold.

Serum thymidine kinase activity in patients with HR-positive/HER2-negative advanced breast cancer treated with ribociclib plus letrozole: results from the prospective BioItaLEE trial

BACKGROUND

Thymidine kinase 1 (TK1) is an enzyme downstream of the CDK4/6 pathway, with a critical role in DNA synthesis; serum TK1 activity (sTKa) is a novel liquid biopsy biomarker of tumour cell proliferation.

METHODS

The phase IIIb, BioItaLEE trial (NCT03439046) collected sera from postmenopausal patients with hormone receptor-positive (HR+), HER2-negative (HER2-) advanced breast cancer (ABC) treated with first-line ribociclib plus letrozole at baseline, day 15 of cycle 1 (C1D15), day 1 of cycle 2 (C2D1), and at first imaging. Associations between sTKa assessed at different time points or sTKa dynamic patterns, and progression-free survival (PFS) were evaluated using multivariate Cox models.

RESULTS

Overall, 287 patients were enroled. Median follow-up was 26.9 months. High sTKa (>median) at baseline was associated with higher risk of progression (hazard ratio [HR], 2.21; 95% confidence interval [95% CI], 1.45, 3.37; P = 0.0002); similar results were observed for patients with high sTKa levels at C1D15 and C2D1. Early sTKa dynamic patterns were strongly predictive of PFS. The pattern with high sTKa levels at C2D1 following initial decrease at C1D15 was associated with higher risk of progression versus the pattern with low sTKa levels at both time points (HR, 2.89; 95% CI, 1.57, 5.31; P = 0.0006), while the pattern with high sTKa levels at C1D15 was associated with the shortest PFS (HR, 5.65; CI: 2.84, 11.2; P < 0.0001). Baseline and dynamic sTKa changes provided independent information.

CONCLUSIONS

sTKa appears to be a new promising prognostic and pharmacodynamic biomarker in patients with HR+/HER2- ABC treated with ribociclib plus letrozole as first-line therapy.

Multigene signatures for early breast cancer in clinical practice: A report of the Lombardy genomic assays for breast cancer working group

The increasing understanding of breast cancer biology has provided the basis for the development of multigene signatures aimed to improve the capability of clinicians to assess patients' prognostication and risk stratification. Incorporating these tools in clinical practice has profoundly impacted on the decision-making process for the adjuvant therapy of patients with ER+/HER2- early breast cancer and the results from prospective adjuvant trials have strengthened the clinical utility of multigene signatures in this setting. In July 2019, Lombardy was the first Region in Italy to reimburse genomic testing for patients with ER+/HER2- early breast cancer. Three years later, a group of investigators from six referral Cancer Centers in Lombardy convened to debate the use of multigene signatures in clinical practice and share their own experience with the tests after reimbursement. Here, we reviewed relevant data on the role of multigene signatures in tailoring adjuvant chemotherapy for patients with ER+/HER2- early breast cancer and discussed about the optimal use of these assays in current clinical practice. As the treatment landscape of early breast cancer evolves and novel questions about the possible additional applications of multigene assays arise, we also provide our viewpoint on the potential implementation of the assays in the evolving scenario ER+/HER2- early breast cancer treatment.

Real-World Effectiveness of Denosumab and Bisphosphonates on Risk of Vertebral Fractures in Women with Breast Cancer Undergoing Treatment with Aromatase Inhibitors

Bone-active drugs are recommended to protect the skeleton from detrimental actions of aromatase inhibitors (AIs). However, most of literature data are focused on bone mineral density (BMD), whereas data on fractures are scant. The aim of this prospective study was to investigate the real-life effectiveness of denosumab, oral bisphosphonates (BPs) and intravenous zoledronate on risk of vertebral fractures (VFs) induced by AIs. 567 consecutive women (median age 62 years, range 28-83) with early breast cancer undergoing treatment with AIs were evaluated for morphometric VFs and BMD at baseline and after 18-24 months of follow-up. After enrollment, 268 women (47.3%) started denosumab 60 mg subcutaneously every 6 months, 115 (20.3%) BPs (59 with oral BPs and, 56 with intravenous zoledronate 5 mg/12 months), whereas 184 women (32.5%) were not treated with bone-active drugs for several reasons. During follow-up, 54 women (9.5%) developed incident VFs in association with age of subjects (P &lt; 0.001), baseline FRAX scores for major fractures (P &lt; 0.001) and hip fractures (P = 0.003), pre-existing VFs (P &lt; 0.001), change in BMD at lumbar spine (P = 0.015), femoral neck (P = 0.003) and total hip (P &lt; 0.001). Risk of VFs was higher in subjects who were untreated as compared to those treated with bone-active drugs (32/184 vs. 22/383; P &lt; 0.001). Specifically, fracture risk was significantly decreased by denosumab [odds ratio (OR) 0.22; P &lt; 0.001] and zoledronate (OR 0.27; P = 0.035), but not by oral BPs (P = 0.317). These data suggest that in real-world clinical practice, denosumab and zoledronate can reduce AI-related risk of VFs after only 24 months of treatment.

PARP-inhibitors for BRCA1/2-related advanced HER2-negative breast cancer: A meta-analysis and GRADE recommendations by the Italian Association of Medical Oncology

BACKGROUND

Approximately 5-10% of unselected breast cancer (BC) patients retain a hereditary predisposition related to a germline mutation in BRCA1/2 genes. The poly-ADP ribose polymerase (PARP)-inhibitors olaparib and talazoparib have been granted marketing authorization by both FDA and EMA for adults with BRCA1/2 germline mutations and HER2-negative (HER2-) advanced BC based on the results from the phase III OlympiAd and EMBRACA trials.

METHODS

The panel of the Italian Association of Medical Oncology (AIOM) Clinical Practice Guidelines on Breast Cancer addressed two critical clinical questions, adopting the Grades of Recommendation, Assessment, Development and Evaluation (GRADE) approach and the Evidence to Decision framework (EtD), to develop recommendations on the use of PARP-inhibitors, with respect to single-agent chemotherapy, in patients with BRCA-related triple-negative (clinical question 1) and hormone receptor-positive (HR+)/HER2- (clinical question 2) advanced BC.

RESULTS

Two studies were eligible (OlympiAd and EMBRACA). For both clinical questions, the Panel judged the benefit/harm balance probably in favor of the intervention, given the favorable impact in terms of PFS, ORR, and QoL at an acceptable cost in terms of toxicity; the overall certainty of the evidence was low. The panel's final recommendations were conditional in favor of PARP-inhibitors over single-agent chemotherapy in both HR+/HER2-and triple-negative BC. Finally, the Panel identified and discussed areas of uncertainty calling for further exploration.

CONCLUSIONS

The Panel of AIOM BC Clinical Practice Guideline provided clinical recommendations on the use of PARP-inhibitors, with respect to single-agent chemotherapy, in patients with BRCA-related HER2-advanced BC by adopting the GRADE methodology.

Extended adjuvant endocrine treatment for premenopausal women: A Delphi approach to guide clinical practice

The use of an aromatase inhibitor (AI) in combination with ovarian function suppression (OFS) has become the mainstay of adjuvant endocrine therapy in high-risk premenopausal patients with hormone receptor-positive breast cancer. Although five years of such therapy effectively reduces recurrence rates, a substantial risk of late recurrence remains in this setting. Multiple trials have shown that extending AI treatment beyond five years could offer further protection. However, as these studies comprised only postmenopausal patients, no direct evidence currently exists to inform about the potential benefits and/or side effects of extended AI + OFS therapies in premenopausal women. Given these grey areas, we conducted a Delphi survey to report on the opinion of experts in breast cancer treatment and summarize a consensus on the discussed topics. A total of 44 items were identified, all centred around two main themes: 1) defining reliable prognostic factors to pinpoint premenopausal patients eligible for endocrine therapy extension; 2) designing how such therapy should optimally be administered in terms of treatment combinations and duration based on patients' menopausal status. Each item was separately discussed and anonymously voted by 12 experts representing oncological institutes spread across Italy. The consensus threshold was reached in 36 out of 44 items (82%). Herein, we discuss the levels of agreement/disagreement achieved by each item in relation to the current body of literature. In the absence of randomized trials to guide the tailoring of extended AI treatment in premenopausal women, conclusions from our study provide a framework to assist routine clinical practice.

Safety and Efficacy of Ribociclib in Combination with Letrozole in Patients with HR+, HER2- Advanced Breast Cancer: Results from the Italian Subpopulation of Phase 3b CompLEEment-1 Study

BACKGROUND

Ribociclib plus letrozole demonstrated manageable safety and efficacy profiles in hormone receptor-positive (HR+), human epidermal growth factor receptor-2-negative (HER2-) advanced breast cancer (ABC) in the Phase 3b CompLEEment-1 trial.

OBJECTIVE

To evaluate the safety and efficacy of ribociclib plus letrozole in the Italian subpopulation with HR+, HER2- ABC from the CompLEEment-1 trial.

PATIENTS AND METHODS

Patients with HR+, HER2- ABC received ribociclib (600 mg/day, 3 weeks on/1 week off) plus letrozole (2.5 mg/day) while men and premenopausal women additionally received goserelin. Patients were allowed with ≤ 1 line of prior chemotherapy and an Eastern Cooperative Oncology Group performance status of ≤ 2. The primary outcome included safety and tolerability.

RESULTS

Of the 554 Italian patients, 246 (44.4 %) patients completed treatment. The reasons for treatment discontinuation included progressive disease (PD; 36.6 %), adverse events (AEs; 11.9 %), and death (1.6 %). All-grade AEs and grade ≥ 3 AEs occurred in 98.9 % and 77.8 % patients, respectively. The most common treatment-related AEs were neutropenia (73.6 %), followed by leukopenia (32.1 %), and nausea (25.3 %). The overall response rate was 28.2 % (95 % confidence interval [CI], 24.4-32.1); clinical benefit rate was 71.7 % (95 % CI, 67.7-75.4); and median time to progression was 26.7 months (95 % CI, 24.8-non-estimable). Health-related quality of life scores were maintained during treatment.

CONCLUSION

The safety and efficacy profiles of ribociclib plus letrozole in the Italian subpopulation was found to be consistent with the CompLEEment-1 global population result, MONALEESA-2, and MONALEESA-7 outcomes, which reaffirm ribociclib plus letrozole as the frontline treatment option in patients with HR+, HER2- ABC.

TRIAL REGISTRATION NUMBER AND DATE OF REGISTRATION

NCT02941926 (30 November 2016).

Controversial topics in metastatic HR+/HER2- breast cancer: Guiding treatment by a modified Delphi approach

The treatment of HR+/HER2- metastatic breast cancer with cyclin-dependent kinases 4 and 6 inhibitors combined with endocrine therapy has recently emerged as the most relevant therapeutic strategy. However, in routine clinical practice, the best therapeutic approach in patients with comorbidities at early relapsing or ab initio metastatic disease, PI3KCA mutation, is still debated among oncologists. Given these areas of uncertainty, we conducted a Delphi survey to describe and confront the level of agreement or disagreement between clinicians working in referral vs local spoke oncological hospitals and summarize a consensus on these debated topics. In total, 56 items were drafted using the Nominal Group Technique and used for the Delphi Survey. A total of 46 clinicians participated in the survey. Overall, the consensus threshold among all participants was reached in 46/56 items (82%), and Delphi Survey results showed a high level of consensus. For the 10 items (18%) that did not reach the consensus threshold, possible explanations considering differences in clinical practice and recent findings from literature are provided in the Discussion. Outcomes from the present survey may help guide treatment in multiple comorbidities, early recurring and ab initio metastatic disease, and PI3KCA mutation, where evidence from randomized trials and level 1 evidence is currently missing.

From seaside to bedside: Current evidence and future perspectives in the treatment of breast cancer using marine compounds

To date, only few marine natural compounds have been proved to be active in breast cancer (BC). The main marine-derived drugs that have been studied for the treatment of BC are tubulin-binding agents (eribulin and plocabulin), DNA-targeting agents (cytarabine and minor groove binders—trabectedin and lurbinectedin) and Antibody-Drug Conjugates (ADCs). Notably, eribulin is the only approved cytotoxic drug for the treatment of advanced BC (ABC), while cytarabine has a limited indication in case of leptomeningeal diffusion of the disease. Also plocabulin showed limited activity in ABC but further research is needed to define its ultimate potential role. The available clinical data for both trabectedin and lurbinectedin are of particular interest in the treatment of BRCA-mutated tumours and HR deficient disease, probably due to a possible immune-mediated mechanism of action. One of the most innovative therapeutic options for the treatment of BC, particularly in TNBC and HER2-positive BC, are ADCs. Some of the ADCs were developed using a specific marine-derived cytotoxic molecule as payload called auristatin. Among these, clinical data are available on ladiratuzumab vedotin and glembatumumab vedotin in TNBC, and on disitamab vedotin and ALT-P7 in HER2-positive patients. A deeper knowledge of the mechanism of action and of the potential predictive factors for response to marine-derived drugs is important for their rational and effective use, alone or in combination. In this narrative review, we discuss the role of marine-derived drugs for the treatment of BC, although most of them are not approved, and the opportunities that could arise from the potential treasure trove of the sea for novel BC therapeutics.

Persistence of long-term COVID-19 sequelae in patients with cancer: An analysis from the OnCovid registry

INTRODUCTION

A significant proportion of patients with cancer who recover from Coronavirus Disease 2019 (COVID-19) may experience COVID-19 sequelae in the early post-infection phase, which negatively affect their continuity of care and oncological outcome. The long-term prevalence and clinical impact of the post-COVID-19 syndrome in patients with cancer are largely unknown.

METHODS

In this study, we describe the time course of COVID-19 sequelae in patients with non-advanced cancers enrolled in the OnCovid registry.

RESULTS

Overall, 186 patients were included, with a median observation period of 9.9 months (95%CI:8,8-11.3) post-COVID-19 resolution. After a median interval of 2.3 months post-COVID-19 (interquartile range: 1.4-3.7), 31 patients (16.6%) reported ≥1 sequelae, including respiratory complications (14, 7.6%), fatigue (13, 7.1%), neuro-cognitive sequelae (7, 3.8%). The vast majority of the patients were not vaccinated prior to COVID-19. COVID-19-related sequelae persisted in 9.8% and 8% of patients 6 and 12 months after COVID-19 resolution. Persistence of sequelae at first oncological follow-up was associated with history of complicated COVID-19 (45.2% vs 24.8%, p = 0.0223), irrespective of oncological features at COVID-19 diagnosis.

CONCLUSION

This study confirms for the first time that, in a largely unvaccinated population, post-COVID-19 syndrome can affect a significant proportion of patients with non-advanced cancer who recovered from the acute illness. COVID-19 sequelae may persist up to 12 months in some patients, highlighting the need for dedicated prevention and supportive strategies.

Outcomes of the SARS-CoV-2 omicron (B.1.1.529) variant outbreak among vaccinated and unvaccinated patients with cancer in Europe: results from the retrospective, multicentre, OnCovid registry study

BACKGROUND

The omicron (B.1.1.529) variant of SARS-CoV-2 is highly transmissible and escapes vaccine-induced immunity. We aimed to describe outcomes due to COVID-19 during the omicron outbreak compared with the prevaccination period and alpha (B.1.1.7) and delta (B.1.617.2) waves in patients with cancer in Europe.

METHODS

In this retrospective analysis of the multicentre OnCovid Registry study, we recruited patients aged 18 years or older with laboratory-confirmed diagnosis of SARS-CoV-2, who had a history of solid or haematological malignancy that was either active or in remission. Patient were recruited from 37 oncology centres from UK, Italy, Spain, France, Belgium, and Germany. Participants were followed up from COVID-19 diagnosis until death or loss to follow-up, while being treated as per standard of care. For this analysis, we excluded data from centres that did not actively enter new data after March 1, 2021 (in France, Germany, and Belgium). We compared measures of COVID-19 morbidity, which were complications from COVID-19, hospitalisation due to COVID-19, and requirement of supplemental oxygen and COVID-19-specific therapies, and COVID-19 mortality across three time periods designated as the prevaccination (Feb 27 to Nov 30, 2020), alpha-delta (Dec 1, 2020, to Dec 14, 2021), and omicron (Dec 15, 2021, to Jan 31, 2022) phases. We assessed all-cause case-fatality rates at 14 days and 28 days after diagnosis of COVID-19 overall and in unvaccinated and fully vaccinated patients and in those who received a booster dose, after adjusting for country of origin, sex, age, comorbidities, tumour type, stage, and status, and receipt of systemic anti-cancer therapy. This study is registered with ClinicalTrials.gov, NCT04393974, and is ongoing.

FINDINGS

As of Feb 4, 2022 (database lock), the registry included 3820 patients who had been diagnosed with COVID-19 between Feb 27, 2020, and Jan 31, 2022. 3473 patients were eligible for inclusion (1640 [47·4%] were women and 1822 [52·6%] were men, with a median age of 68 years [IQR 57-77]). 2033 (58·5%) of 3473 were diagnosed during the prevaccination phase, 1075 (31·0%) during the alpha-delta phase, and 365 (10·5%) during the omicron phase. Among patients diagnosed during the omicron phase, 113 (33·3%) of 339 were fully vaccinated and 165 (48·7%) were boosted, whereas among those diagnosed during the alpha-delta phase, 152 (16·6%) of 915 were fully vaccinated and 21 (2·3%) were boosted. Compared with patients diagnosed during the prevaccination period, those who were diagnosed during the omicron phase had lower case-fatality rates at 14 days (adjusted odds ratio [OR] 0·32 [95% CI 0·19-0·61) and 28 days (0·34 [0·16-0·79]), complications due to COVID-19 (0·26 [0·17-0·46]), and hospitalisation due to COVID-19 (0·17 [0·09-0·32]), and had less requirements for COVID-19-specific therapy (0·22 [0·15-0·34]) and oxygen therapy (0·24 [0·14-0·43]) than did those diagnosed during the alpha-delta phase. Unvaccinated patients diagnosed during the omicron phase had similar crude case-fatality rates at 14 days (ten [25%] of 40 patients vs 114 [17%] of 656) and at 28 days (11 [27%] of 40 vs 184 [28%] of 656) and similar rates of hospitalisation due to COVID-19 (18 [43%] of 42 vs 266 [41%] of 652) and complications from COVID-19 (13 [31%] of 42 vs 237 [36%] of 659) as those diagnosed during the alpha-delta phase.

INTERPRETATION

Despite time-dependent improvements in outcomes reported in the omicron phase compared with the earlier phases of the pandemic, patients with cancer remain highly susceptible to SARS-CoV-2 if they are not vaccinated against SARS-CoV-2. Our findings support universal vaccination of patients with cancer as a protective measure against morbidity and mortality from COVID-19.

FUNDING

National Institute for Health and Care Research Imperial Biomedical Research Centre and the Cancer Treatment and Research Trust.

Heterogeneity of triple-negative breast cancer: understanding the Daedalian labyrinth and how it could reveal new drug targets

INTRODUCTION

Triple-negative breast cancer (TNBC) is considered the most aggressive breast cancer subtype with the least favorable outcomes. However, recent research efforts have generated an enhanced knowledge of the biology of the disease and have provided a new, more comprehensive understanding of the multifaceted ecosystem that underpins TNBC.

AREAS COVERED

In this review, the authors illustrate the principal biological characteristics of TNBC, the molecular driver alterations, targetable genes, and the biomarkers of immune engagement that have been identified across the subgroups of TNBC. Accordingly, the authors summarize the landscape of the innovative and investigative biomarker-driven therapeutic options in TNBC that emerge from the unique biological basis of the disease.

EXPERT OPINION

The therapeutic setting of TNBC is rapidly evolving. An enriched understanding of the tumor spatial and temporal heterogeneity and the surrounding microenvironment of this complex disease can effectively support the development of novel and tailored opportunities of treatment.

Circulating tumor DNA (ctDNA) and serum thymidine kinase 1 activity (TKa) matched dynamics in patients (pts) with hormone receptor–positive (HR+), human epidermal growth factor 2–negative (HER2-) advanced breast cancer (ABC) treated in first-line (1L) with ribociclib (RIB) and letrozole (LET) in the BioItaLEE trial

1012

Background: Independent early dynamic assessment (baseline [D0] and day 15 of first cycle [D15]) of both TKa and ctDNA was prognostic and predictive in pts with HR+, HER2− ABC treated with RIB+LET enrolled in the BioItaLEE trial (NCT03439046). Here we performed a combined analysis of these two biomarkers. Methods: 287 pts were enrolled in the study. Overall, early dynamics were assessable for both biomarkers in 241/287 pts (84.0%). Methods applied for ctDNA and TKa evaluation were previously reported. For ctDNA, samples were defined as wild type (WT) if no mutations were observed at D0 and D15, ctDNA positive (+) if with or negative (-) if without a primary target mutation at D15. Samples were TKa+ or TKa- if TKa levels were above or below the limit of detection at D15. According to ctDNA and TKa pts were classified as: WT/TKa-, WT/TKa+, ctDNA-/TKa-, ctDNA-/TKa+, ctDNA+/TKa- and ctDNA+/TKa+ and then divided into 3 main study groups (GRs) WT/TKa- (GR1, n = 126), WT/TKa+, ctDNA-/TKa-, ctDNA-/TKa+, ctDNA+/TKa- (GR2, n = 96) and ctDNA+/TKa+ (GR3, n = 19). The association between biomarkers and PFS (progression-free survival) was estimated using Kaplan-Meier analysis and multivariate Cox models with 95% confidence intervals (CIs) adjusted for clinical variables. Results: Median follow-up was 26.9 months. In multivariate Cox models both TKa dynamics and mutational tumor burden at D15 were independently predictive of PFS. Hazard ratios (HRs) were 0.37 (95% CI: 0.23-0.60; p < 0.0001) for WT vs ctDNA+ and 0.56 (95% CI: 0.32-1.00; p = 0.0506) for ctDNA- vs ctDNA+. For TKa, HR was 0.49 (95% CI: 0.30-0.80; p = 0.0040) in TKa- vs TKa+. Interestingly combining the two variables further improve prediction of outcome. HRs for TKa- vs TKa+ were 0.17 (95% CI: 0.09-0.32; p < 0.0001), 0.28 (95% CI: 0.13-0.59; p = 0.0009) and 0.44 (95% CI: 0.23-0.86; p = 0.0169) in WT, ctDNA- and ctDNA+ pts, respectively. Considering the 3 study GRs, median PFSs (95% CI) were not reached (27.89, NE), 19.58 (13.83, 23.39) and 6.65 (2.83, 12.16) months in GR1, GR2 and GR3, respectively, p < 0.001. At multivariate Cox models, HRs of GR1 and GR2 compared with GR3 were 0.17 (95% CI: 0.09-0.32; p < 0.0001) and 0.37 (95% CI: 0.20-0.67; p = 0.001) respectively. Conclusions: These findings suggest that combining the early dynamic assessment of both ctDNA and TKa may improve outcome prediction in pts treated with RIB+LET. Pts with ctDNA+/TKa+ are strongly enriched for non-responders. TKa and ctDNA capture different features of tumor biological activity and their combination warrants further evaluation in relation to other treatments, settings, and diseases. Clinical trial information: NCT03439046.