Effect of age on safety and efficacy of novel cancer drugs investigated in early-phase clinical trials.

BACKGROUND: Elderly patients are underrepresented in clinical trials, particularly in early-phase studies. Our study assessed the safety and efficacy of novel anti-cancer treatments investigated in early-phase clinical trials, comparing outcomes between younger and elderly patients. METHODS: This retrospective study analyzed data from patients enrolled in phase I/II trials at our center between January 2014 and April 2021. We evaluated clinicopathologic characteristics, toxicity, and clinical efficacy, categorizing patients into younger (≤ 65 years) and elderly (> 65 years) groups. RESULTS: 419 patients were included with a median age of 56 years. Among these, 107 (26 %) were older than 65 years. Predominant cancers included breast (48 %), lung (10 %), and melanoma (5 %). Patients were treated in 64 trials, predominantly receiving immunotherapy-based (47 %) or targeted therapy-based (45 %) treatment. Elderly presented with poorer ECOG performance status (P = 0.001) and had fewer prior therapy lines (P = 0.01) than younger patients. Grade ≥ 3 adverse events (AEs) were similar across age groups (31 % younger vs 33 % elderly; P = 0.7), including in combination therapy scenarios. However, elderly patients experienced more AEs with antibody-drug conjugates compared to younger counterparts (56 % vs 14 %, P = 0.036) and were more likely to discontinue treatment due to toxicity (15 % vs 7 %; P = 0.011). No significant age-related differences in response rates and survival outcomes were observed across treatment modalities, except for immunotherapy-based regimens for which elderly patients exhibited higher response rates, disease control rates, and prolonged progression-free survival. CONCLUSIONS: Our findings suggest that elderly exhibit comparable safety and efficacy outcomes to younger patients in early-phase clinical trials for new cancer drugs. This underscores the importance of including elderly patients in phase I/II trials to ensure the generalizability of study results and mitigate age-related disparities in cancer treatment access.

PARP Inhibitors for Breast Cancer Treatment: A Review.

Importance: Poly(adenosine diphosphate-ribose) polymerase (PARP) inhibitors have revolutionized the treatment of patients with germline BRCA1/2-associated breast cancer, representing the first targeted therapy capable of improving outcomes in patients with hereditary tumors. However, resistance to PARP inhibitors occurs in almost all patients. Observations: This narrative review summarizes the biological rationale behind the use of PARP inhibitors in breast cancer, as well as the available evidence, recent progress, and potential future applications of these agents. Recent studies have shown that the benefit of PARP inhibitors extends beyond patients with germline BRCA1/2-associated metastatic breast cancer to patients with somatic BRCA1/2 variants and to those with germline PALB2 alterations. Moreover, these agents proved to be effective both in the metastatic and adjuvant settings. However, patients with metastatic breast cancer usually do not achieve the long-term benefit from PARP inhibitors observed in other tumor types. Mechanisms of resistance have been identified, but how to effectively target them is largely unknown. Ongoing research is investigating both novel therapeutics and new combination strategies to overcome resistance. PARP1-selective inhibitors, by sparing the hematological toxic effects induced by the PARP2 blockade, are promising agents to be combined with chemotherapy, antibody-drug conjugates, and other targeted therapies. Conclusions and Relevance: Although the efficacy of PARP inhibitors is well established, many questions persist. Future research should focus on identifying predictive biomarkers and therapeutic strategies to overcome resistance. Integrating well-designed translational efforts into all clinical studies is thereby crucial to laying the groundwork for future insights from ongoing research.

Baseline Tumor Size as Prognostic Index in Patients With Advanced Solid Tumors Receiving Experimental Targeted Agents.

BACKGROUND: Baseline tumor size (BTS) has been associated with outcomes in patients with cancer treated with immunotherapy. However, the prognostic impact of BTS on patients receiving targeted therapies (TTs) remains undetermined. METHODS: We reviewed data of patients with advanced solid tumors consecutively treated within early-phase clinical trials at our institution from 01/2014 to 04/2021. Treatments were categorized as immunotherapy-based or TT-based (biomarker-matched or not). BTS was calculated as the sum of RECIST1.1 baseline target lesions. RESULTS: A total of 444 patients were eligible; the median BTS was 69 mm (IQR 40-100). OS was significantly longer for patients with BTS lower versus higher than the median (16.6 vs. 8.2 months, P < .001), including among those receiving immunotherapy (12 vs. 7.5 months, P = .005). Among patients receiving TT, lower BTS was associated with longer PFS (4.7 vs. 3.1 months, P = .002) and OS (20.5 vs. 9.9 months, P < .001) as compared to high BTS. However, such association was only significant among patients receiving biomarker-matched TT, with longer PFS (6.2 vs. 3.3 months, P < .001) and OS (21.2 vs. 6.7 months, P < .001) in the low-BTS subgroup, despite a similar ORR (28% vs. 22%, P = .57). BTS was not prognostic among patients receiving unmatched TT, with similar PFS (3.7 vs. 4.4 months, P = .30), OS (19.3 vs. 11.8 months, P = .20), and ORR (33% vs. 28%, P = .78) in the 2 BTS groups. Multivariate analysis confirmed that BTS was independently associated with PFS (P = .03) and OS (P < .001) but not with ORR (P = .11). CONCLUSIONS: Higher BTS is associated with worse survival outcomes among patients receiving biomarker-matched, but not biomarker-unmatched TT.

Immune-Related Adverse Event Likelihood Score Identifies "Pure" IRAEs Strongly Associated With Outcome in a Phase I-II Trial Population.

BACKGROUND: Immune-related adverse events (IRAE) pose a significant diagnostic and therapeutic challenge in patients treated with immune-oncology (IO) drugs. IRAEs have been suggested to correlate with better outcome, but studies are conflicting. Estimating the true incidence of IRAEs is particularly difficult in the early phase I/II trial setting. A key issue is the lack of IRAE diagnostic criteria, necessary to discriminate "pure" IRAEs from other treatment-related adverse events not sustained by an autoimmune process. METHODS: In patients treated with immune-oncology (IO) drugs in phases I-II trials at our institute, we identified high confidence (HC) or low confidence (LC) IRAEs by clinical consensus. We empirically developed an IRAE likelihood score (ILS) based on commonly available clinical data. Correlation with outcome was explored by multivariate Cox analysis. To mitigate immortal time-bias, analyses were conducted (1) at 2-month landmark and (2) modeling IRAEs as time-dependent covariate. RESULTS: Among 202 IO-treated patients, 29.2% developed >1 treatment-related adverse events (TRAE). Based on ILS >5, we classified patients in no IRAE (n = 143), HC IRAE (n = 24), or LC IRAE (n = 35). hazard ratios (HR) for HC were significantly lower than LC patients (HR for PFS ranging 0.24-0.44, for OS 0.18-0.23, all P < .01). CONCLUSION: ILS provides a simple system to identify bona fide IRAEs, pruning for other treatment-related events likely due to different pathophysiology. Applying stringent criteria leads to lower and more reliable estimates of IRAE incidence and identifies events with significant impact on survival.

Clinicopathological features and survival outcomes of luminal-like breast tumors with estrogen receptor loss at metastatic recurrence: A case-control study.

INTRODUCTION: Estrogen receptor (ER) loss at metastatic relapse occurs in up to 20% of luminal-like primary breast tumors. Data about clinicopathological features associated with ER loss and its prognostic significance are limited. METHODS: In a nested-case-control study, we compared clinicopathological characteristics and clinical outcomes between a cohort of 51 patients with primary ER+ /HER2- and paired triple-negative metastasis (LUM-TN) and two control cohorts of paired early-metastatic ER+ /HER2- (LUM-LUM, n = 50) and triple-negative (TN-TN, n = 49) breast cancers. Stromal tumor-infiltrating lymphocytes (TILs) were assessed according to the TILs Working Group recommendations as continuous and discrete variables with cutoffs (20%, 40%). RESULTS: LUM-TN tumors had lower ER expression than LUM-LUM tumors, but lower grade and Ki67 than TN-TN cases. Median distant-metastasis free survival was similar for LUM-TN and LUM-LUM cohorts, but significantly longer than in TN-TN cases (log-rank P < 0.001). LUM-TN and TN-TN cohorts had a comparable survival from the time of metastatic recurrence, which was significantly shorter than in patients with LUM-LUM tumors (log-rank P < 0.001). High TILs were associated with worse outcomes in patients with ER loss (P < 0.001). CONCLUSIONS: Breast tumors with ER loss at metastatic relapse have intermediate features and outcomes compared with metastatic luminal-like and ab initio triple-negative tumors. Further investigation on the biological mechanisms underpinning the loss of ER expression is ongoing.

Clinical utility of genomic signatures for the management of early and metastatic triple-negative breast cancer.

PURPOSE OF REVIEW: This comprehensive review aims to provide timely and relevant insights into the current therapeutic landscape for triple-negative breast cancer (TNBC) and the molecular features underlying this subtype. It emphasizes the need for more reliable biomarkers to refine prognostication and optimize therapy, considering the aggressive nature of TNBC and its limited targeted treatment options. RECENT FINDINGS: The review explores the multidisciplinary management of early TNBC, which typically involves systemic chemotherapy, surgery, and radiotherapy. It highlights the emergence of immune checkpoint inhibitors (ICIs), poly(ADP-ribose) polymerase (PARP) inhibitors, and antibody-drug conjugates (ADCs) as promising therapeutic strategies for TNBC. Recent clinical trials investigating the use of ICIs in combination with chemotherapy and the approval of pembrolizumab and atezolizumab for PD-L1-positive metastatic TNBC are discussed. The efficacy of PARP inhibitors and ADCs in treating TNBC patients with specific genetic alterations is also highlighted. SUMMARY: The findings discussed in this review have significant implications for clinical practice and research in TNBC. The identification of distinct molecular subtypes through gene expression profiling has enabled a better understanding of TNBC heterogeneity and its clinical implications. This knowledge has the potential to guide treatment decisions, as different subtypes display varying responses to neoadjuvant chemotherapy. Furthermore, the review emphasizes the importance of developing reliable genomic and transcriptomic signatures as biomarkers to refine patient prognostication and optimize therapy selection in TNBC. Integrating these signatures into clinical practice may lead to more personalized treatment approaches, improving outcomes for TNBC patients.

Breast Cancer with Brain Metastasis: Molecular Insights and Clinical Management.

Breast cancer is the most frequently diagnosed malignancy worldwide and the leading cause of cancer-related death among women. Brain metastases are a primary contributor to mortality, as they often go undetected until late stages due to their dormant nature. Moreover, the clinical management of brain metastases is complicated by the relevant issue of blood-brain barrier penetration. The molecular pathways involved in the formation, progression, and colonization of primary breast tumors and subsequent brain metastases are diverse, posing significant hurdles due to the heterogeneous nature of breast cancer subtypes. Despite advancements in primary breast cancer treatments, the prognosis for patients with brain metastases remains poor. In this review, we aim to highlight the biological mechanisms of breast cancer brain metastases by evaluating multi-step genetic pathways and to discuss currently available and emerging treatment strategies to propose a prospective overview of the management of this complex disease.

Evolution of biological features of invasive lobular breast cancer: Comparison between primary tumour and metastases.

BACKGROUND: Invasive lobular carcinoma (ILC) has unique clinical-biological features. Phenotypical differences between primary tumours (PTs) and metastases (M) have been described for invasive ductal carcinoma, but data on ILC are limited. METHODS: We retrospectively analysed patients with recurrent ILC from our institution from 2013 to 2020. We evaluated the discordance of the oestrogen receptor (ER), progesterone receptor (PgR) and HER2 between PT and M, to understand prognostic and therapeutic implications. RESULTS: Thirteen percent (n = 91) of all patients had ILC. We observed 15%, 44% and 5% of ER, PgR and HER2 status discordance between PT and M. ER/PgR discordance was related to receptor loss and HER2 mainly due to gain. PT presented a luminal-like phenotype (93%); 6% and 1% were triple-negative (TNBC) and HER2-positive. In M, there was an increase in TNBC (16%) and HER2-positive (5%). Metastasis-free survival and overall survival (OS) were different according to clinical phenotype, with poorer prognosis for HER2+ and TNBC (p < 0.001); OS after metastatic progression did not differ across phenotypes (p = 0.079). In luminal-like ILC (n = 85) at diagnosis, we found that OS after relapse was poorer in patients experiencing a phenotype switch to TNBC but improved in patients with HER2 gain (p = 0.0028). Poorer survival was reported in patients with a PgR and/or ER expression loss of ≥25%. There was HER2-low enrichment in M1 (from 37% to 58%): this change was not associated with OS (p > 0.05). CONCLUSION: Our results suggest that phenotype switch after metastatic progression may be associated with patients' outcomes. Tumour biopsy in recurrent ILC could drive treatment decision-making, with prognostic implications.

HER2-Low Breast Cancer: a New Subtype?

OPINION STATEMENT: Breast cancer (BC) guidelines subdivide the disease into three main groups, namely hormone receptor (HR)-positive HER2-negative, HER2-positive, and triple-negative BC (TNBC). The natural history of the HER2-positive subtype has changed since the introduction of HER-targeted therapies, which demonstrated benefit only in case of HER2 overexpression (IHC, score 3+) or gene amplification. Such observation may depend on direct drug inhibition of HER2 downstream signaling, which is needed for survival and proliferation in HER2-addicted BC. Clinically focused categories cannot comprehensively describe biology, as almost half of the currently defined HER2-negative BCs show some degree of IHC expression and have been recently renamed as HER2-low. Why? As technological breakthroughs enable the synthesis of antibody-drug conjugates (ADCs), target antigens may be viewed not only as a biological switch to be turned on-off by targeted drugs but also as an anchor for ADC docking and tethering. As trastuzumab deruxtecan (T-DXd) has already proven in the clinical trial DESTINY-Breast04, even fewer HER2 available receptors on cancer cells may be sufficient for a clinical benefit. So, for HR-negative HER2-low subtype (~40% of TNBCs), though only 58 patients had been enrolled in DESTINY-Breast04, the observed benefit, together with the dismal prognosis of TNBC, warrants the use of T-DXd. Notably, another topoisomerase-based ADC, sacituzumab govitecan, has already been granted approval for pretreated TNBC (ASCENT). As no head-to-head comparison has been performed, the choice relies on regulatory approvals at the time of patient assessment, critical appraisal of available evidence, and careful evaluation of possible cross-resistance with sequential use of ADCs. As for HR-positive HER2-low disease (~60% of HR-positive tumors), DESTINY-Breast04 provides solid evidence for T-DXd prioritization in either second or third treatment lines. Although the remarkable activity observed in this setting favorably compares with outcomes observed in treatment-naive patients, the ongoing DESTINY-Breast06 will clarify the role of T-DXd in this population.

Unlocking the Resistance to Anti-HER2 Treatments in Breast Cancer: The Issue of HER2 Spatial Distribution.

Approximately 15% of breast cancers are classified as HER2-positive, with an amplification of the ERBB2 gene and/or an overexpression of the HER2 protein. Up to 30% of HER2-positive breast cancers shows heterogeneity in HER2 expression and different patterns of spatial distribution, i.e., the variability in the distribution and expression of the HER2 protein within a single tumour. Spatial heterogeneity may potentially affect treatment, response, assessment of HER2 status and consequently, may impact on the best treatment strategy. Understanding this feature can help clinicians to predict response to HER2-targeted therapies and patient outcomes, and to fine tune treatment decisions. This review summarizes the available evidence on HER2 heterogeneity and spatial distribution and how this may affect current available treatment choices, exploring possible opportunities for overcoming this issue, such as novel pharmacological agents, belonging to the group of antibody-drug conjugates.

HER2-low expression in breast oncology: treatment implications in the smart chemotherapy era.

Human epidermal growth factor 2 (HER2)-low breast cancers, defined as tumors exhibiting a HER2 IHC score of 1+ or 2+ nonamplified, represent an emerging targetable entity in the clinicopathologic landscape of breast cancer. Traditionally considered as not sensitive to HER2-targeting agents, these tumors have shown to be susceptible to a new class of drugs, namely antibody-drug conjugates (ADCs). Indeed, the DESTINY-Breast04 phase 3 trial demonstrated the remarkable activity of trastuzumab deruxtecan for treating both hormone-receptor (HR)-positive and triple-negative metastatic breast cancers that show HER2-low expression, reshaping treatment algorithms for these diseases. Concomitantly, the TROPiCS-02 and the ASCENT phase 3 trials have established the role of the anti-Trop-2 ADC sacituzumab govitecan for HR-positive and triple-negative breast cancer, respectively. A careful evaluation of these trials, with their inclusion/exclusion criteria, efficacy and toxicity results, is required in order to understand how best to treat HER2-low metastatic breast cancer in the context of a rapidly evolving therapeutic landscape. The purpose of this narrative review is to recapitulate the available evidence on the use of ADCs in the treatment of HER2-low breast cancer, providing a perspective on their current role in clinical practice.

Fast Mimicking Diets and Other Innovative Nutritional Interventions to Treat Patients with Breast Cancer.

The impact of nutritional patterns on the risk of breast cancer (BC) is well investigated in the oncology literature, including the type of diets and caloric intake. While obesity and elevated body mass index are well-reported critical risk factors of BC occurrence, there is an expanding area of oncology assessing the impact of caloric intake and nutritional patterns in patients with cancer. Caloric restriction and fast mimicking alimentary regimens have been consistently reported to improve survival outcomes based on preclinical models. Moreover, emerging clinical evidence has paved the way for new metabolic approaches for the treatment of BC, in addition to the established therapeutic arsenal or as alternative options. In this chapter, our aim is to discuss the principal strategies of metabolic manipulation through nutritional interventions for patients with BC as an innovative area of cancer therapy.

Postneoadjuvant treatment for triple-negative breast cancer.

PURPOSE OF REVIEW: Triple-negative breast cancer (TNBC) has been conventionally associated with poor prognosis, as a result of limited therapeutic options. In the early setting, prognosis is informed by clinical-pathological factors; for patients receiving neoadjuvant treatments, pathological complete response (pCR) is the strongest factor. In this review, we mapped the landscape of clinical trials in the postneoadjuvant space, and identified three patterns of clinical trial design. RECENT FINDINGS: For patients at higher risk, effective postneoadjuvant treatments are of paramount importance to address a high clinical need. Postneoadjuvant risk-adapted treatments have demonstrated to improve survival in patients at high of recurrence. SUMMARY: Patients at high risk have indication for adjuvant treatment intensification, informed by baseline clinical, pathological or molecular factors (type 1 approach), on the presence, extent and molecular characteristics of the residual disease at the time of surgery (type 2) or on risk factors assessed in the postsurgical setting (type 3), for example, circulating tumour DNA. Most of the past trials were based on type 2 approaches, for example, with capecitabine and Olaparib. Few trials were based on a type 1 approach, notably pembrolizumab for early TNBC. The clinical validity of type 3 approaches is under investigation in several ongoing trials.

Immunotherapy for triple negative breast cancer: How can pathologic responses to experimental drugs in early-stage disease be enhanced?

INTRODUCTION: The treatment landscape of early triple-negative breast cancer (TNBC) has recently expanded after the Food and Drug Administration (FDA) approval of pembrolizumab in combination with neoadjuvant chemotherapy. The addition of this immune checkpoint inhibitor (ICI) has shown significantly increased pathological complete response (pCR) rate and event-free survival (EFS) in the KEYNOTE-522 phase III trial. Several additional studies are ongoing with the goal of further improving the outcomes and achieving an optimal integration of ICIs in the treatment of TNBC. AREAS COVERED: The article examines pCR and survival rates in TNBC. It appraises clinical trials investigating neoadjuvant ICIs for TNBC and the improvement of pCR rates (biomarker-driven escalation of treatment, optimization of chemotherapy backbone, and addition of locoregional treatments or innovative agents). Insights into the role of pCR as a surrogate endpoint and the possibility of enhancing pCR rates for women affected by early TNBC are offered. EXPERT OPINION: The pharmacopoeia of early TNBC is growing and becoming more heterogeneous with the advent of ICIs; to enhance the clinical benefit of patients, it is necessary to develop response endpoints that consider the mechanism of action of experimental drugs, to optimize patient selection through validated biomarkers, and to compare the most promising treatment strategies in randomized clinical trials.

Emerging treatment landscape of non-muscle invasive bladder cancer.

INTRODUCTION: Non-muscle invasive bladder cancer (NMIBC) accounts for 70-75% of all bladder cancers and is a heterogeneous disease characterized by a wide spectrum of recurrences and progression. Adjuvant treatment for intermediate- and high-risk NMIBC is mainly represented by Bacillus Calmette Guerin (BCG). However, 20%-40% of patients develop disease recurrences or persistence following BCG treatment and are classified as "BCG unresponsive' (BCGu), thus representing a therapeutic challenge due to their worse prognosis and unavailability of effective intravesical treatments. AREAS COVERED: We provide an overview of completed and ongoing clinical trials assessing the role of innovative immunological and target agents in patients with BCGu and BCG naive (BCGn) NMIBCs. New treatment options are emerging, demonstrating promising clinical activity, namely, pembrolizumab, atezolizumab, oportuzumab monatox, nadofaragene firadenovec, and N-803. EXPERT OPINION: The increasing number of newer therapeutic agents for patients with NMIBC poses challenges regarding the choice of the most suited treatment option for each patient and the best treatment sequence, given their diverse mechanisms of action and varying degrees of activity. Tailored treatment approaches are advocated, based on a deeper comprehension of disease features, available therapies, patient's characteristics, and consequently, on the identification and validation of prognostic and predictive biomarkers.

Combining antibody-drug conjugates with immunotherapy in solid tumors: current landscape and future perspectives.

Antibody-drug conjugates (ADCs) and immunotherapy have prompted a revolution in the treatment of cancer. However, only a limited fraction of patients obtained a long-term benefit; consequently, combination studies have become a central focus of the current preclinical and clinical research in oncology. A strong biological rationale supports the investigation of combining ADCs with immunotherapy to overcome the occurrence of resistance and improve patient outcomes. ADCs interact with cancer and immune cells by eliciting mechanisms such as immunogenic cell death, antibody-dependent cell-mediated cytotoxicity and dendritic cell activation, ultimately providing potential synergism with immunotherapy. Indeed, ADCs induce tumor-specific adaptive immunity, increasing the infiltration of T cells into the tumor microenvironment, whereas immune-checkpoint inhibitors reinvigorate exhausted T cells, enhancing antitumor immune responses. In light of the promising preclinical data, several clinical trials are currently underway in multiple tumor types to evaluate the safety and activity of combination regimens. Initial evidence from early phase clinical trials has already reported encouraging signals. This review focuses on the combination of ADCs and immunotherapy, highlighting the key mechanisms underlying the synergistic effect and providing an overview of the available clinical evidence in solid tumors. In addition, opportunities to optimize the combination are explored, such as defining the optimal dose, balancing the risks and benefits of dose modifications, and the possibility of developing novel immunoconjugates.

Bystander effect of antibody-drug conjugates: fact or fiction?

PURPOSE OF REVIEW: Summarizing the current preclinical and clinical evidence about bystander effect of antibody-drug conjugates (ADCs) in solid tumors. RECENT FINDINGS: One of the main challenges of treating solid tumors with ADCs is the heterogeneous expression of the target antigen (Ag), which however may be overcome by the so-called bystander killing effect. This unique, but still debated, feature of certain ADCs is represented by the unintentional payload diffusion from Ag-positive tumor cells to adjacent Ag-negative tumor cells. Some pharmacological characteristics, such as a hydrophobic payload or a cleavable linker, seem to play a major role in this effect. Abundant preclinical evidence of the bystander effect has emerged, and the clinical activity of ADCs in tumors with a heterogeneous Ag expression suggests the relevance of this feature. Additional studies are required to investigate if the bystander effect is necessary for achieving a solid activity with ADCs.

SARS-CoV-2 vaccine in patients with thymic epithelial tumours with and without active or pre-existing autoimmune disorders: Brief report of a TYME network safety analysis.

BACKGROUND: International guidelines recommend severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine for patients with cancer. A substantial risk of developing vaccine-related autoimmune toxicities could be hypothesised for patients with thymic epithelial tumours (TETs) due to their high risk of autoimmune disorders (ADs). Moreover, a cross-reaction between SARS-CoV-2 spike protein antibodies and various tissue proteins has been shown, and antibodies against nucleoproteins showed overlaps in the autoimmune cross-reaction with antibodies to spike protein. Due to the rarity of TETs, no data addressing this hypothesis are available. METHODS: Patients with TETs who received SARS-CoV-2 vaccine, treated in 4 referral centres of the Italian Collaborative Group for ThYmic MalignanciEs (TYME) network between February 2021 and September 2021, were interviewed through a standardised 15-items questionnaire in order to describe the safety of SARS-CoV-2 vaccine in patients affected by TETs. RESULTS: Data from 245 doses of vaccine administered to 126 patients (41 = thymic carcinoma, 85 = thymoma; 38 with AD, of which 26 with active AD) were collected. Nine patients had a previous COVID-19-positive swab. No cases of AD reactivation or worsening of a pre-existing AD were seen in the study population. A new diagnosis of myasthenia gravis likely unrelated to the vaccine was made in two patients after the vaccination. Sixty-four patients (51%) experienced a total of 103 adverse events, all G1/G2, most commonly fatigue, new or worsening muscle pain and chills. None AE required patients' hospitalisation. CONCLUSIONS: SARS-CoV-2 mRNA vaccines appear to be safe in patients with TET, even in case of active or pre-existing AD.

Evolution of low HER2 expression between early and advanced-stage breast cancer.

BACKGROUND: Low human epidermal growth factor receptor 2 (HER2) expression is emerging as an actionable biomarker for the treatment of breast cancer (BC) with novel anti-HER2 drugs. However, the evolution of this biomarker during the course of disease is still poorly characterised, and controversial data exist on its prognostic implications. METHODS: We reviewed data of patients with HER2-negative BC according to the latest ASCO/CAP guidelines referred between January 2014 and December 2020. We grouped patients based on the immunohistochemistry (IHC) expression of HER2, HER2-zero (IHC 0) and HER2-low subgroup (IHC 1+ or 2+/ISH-negative) and evaluated the evolution of HER2 expression between the primary tumour and the first biopsy collected in the advanced setting. Disease-free survival, overall survival and progression-free survival were compared between patients with HER2-zero and HER2-low expression on the primary tumour. RESULTS: 232 patients were included in the analysis. Among the overall population, there was a relevant discordance in HER2 expression between the primary tumour and the matched biopsy (K = 0.33, 95%CI 0.21-0.44): 44% of the HER2-zero primary tumour showed an increased HER2 score on biopsy, and 22% of the HER2-low primary tumours turned into HER2-IHC 0. The findings in the sub-populations of hormone-receptors positive (K = 0.32, 95%CI 0.19-0.45) and triple-negative tumours (K = 0.18, 95%CI -0.09-0.46) were consistent with the primary analysis. No difference in survival outcomes was observed between HER2-low and HER2-zero primary tumours. CONCLUSIONS: HER2-low expression is dynamic in BC and may be enriched in the advanced-stage setting. No prognostic significance was demonstrated for HER2-low expression.