Concomitant Administration of VEGFR Tyrosine Kinase and Proton Pump Inhibitors May Impair Clinical Outcome of Patients With Metastatic Renal Cancer.

INTRODUCTION: The administration of proton pump inhibitors (PPIs) is a common practice to reduce gastro-esophageal adverse events associated with drug treatments but may impair absorption and exposure to oncology drugs. This study investigated the effect of concomitant administration of PPIs and pazopanib, sunitinib and cabozantinib on survival of patients with metastatic clear cell renal carcinoma (mRCC). PATIENTS AND METHODS: Total 451 patients receiving pazopanib, sunitinib and cabozantinib as first line treatment were enrolled in this retrospective study. Patients were defined as "no concomitant PPIs (PPI-)" if no PPIs were administered during TKIs, and as "concomitant PPIs (PPI+)" if the administration of PPIs was at least 75% of the time during which TKIs were given. RESULTS: Eighty patients administered pazopanib were PPI- and 86 PPI+; no difference in PFS was observed (10.7 vs. 11.9 months, P = .79). If patients were stratified as short (n = 89) and long (n = 77) responders, there was a significant difference in terms of PFS in PPI+ (n = 47) versus PPI- (n = 30) in long responders, being 24.7 versus 38 months (P = .04), respectively. In the sunitinib cohort, no significant difference of PFS in PPI+ (n = 102) versus PPI- (n = 131) was found, being 11.3 versus 18.1 months, respectively (P=0.15). In the cabozantinib cohort, there was a statistically significant difference in PFS of PPI+ versus PPI- (6 months vs. not reached, P = .04). No correlation with adverse events was found. CONCLUSIONS: This study demonstrates an association between PPIs and impaired PFS in mRCC patients given pazopanib and cabozantinib and recommends caution on their concomitant use.

Opioid metabolism and drug-drug interaction in cancer.

Concomitant use of multiple drugs in most patients with cancer may result in drug-drug interactions (DDIs), potentially causing serious adverse effects. These patients often experience unrelieved cancer-related pain (CRP) during and after cancer treatment, which can lead to a reduced quality of life. Opioids can be used as part of a multimodal pain management strategy when non-opioid analgesics are not providing adequate pain relief, not tolerated, or are contraindicated. However, due to their narrow therapeutic window, opioids are more susceptible to adverse events when a DDI occurs. Clinically relevant DDIs with opioids are usually pharmacokinetic, mainly occurring via metabolism by cytochrome P450 (CYP). This article aims to provide an overview of potential DDIs with opioids often used in the treatment of moderate-to-severe CRP and commonly used anticancer drugs such as chemotherapeutics, tyrosine kinase inhibitors (TKIs), or biologics. A DDI-checker tool was used to contextualize the tool-informed DDI assessment outcomes with clinical implications and practice. The findings were compared to observations from a literature search conducted in Embase and PubMed to identify clinical evidence for these potential DDIs. The limited results mainly included case studies and retrospective reviews. Some potential DDIs on the DDI-checker were aligned with literature findings, while others were contradictory. In conclusion, while DDI-checkers are useful tools in identifying potential DDIs, it is necessary to incorporate literature verification and comprehensive clinical assessment of the patient before implementing tool-informed decisions in clinical practice.

Endocrine-metabolic assessment checklist for cancer patients treated with immunotherapy: A proposal by the Italian Association of Medical Oncology (AIOM), Italian Association of Medical Diabetologists (AMD), Italian Society of Diabetology (SID), Italian Society of Endocrinology (SIE) and Italian Society of Pharmacology (SIF) multidisciplinary group.

Immunotherapy with immune checkpoint inhibitors (ICI) is increasingly employed in oncology. National and international endocrine and oncologic scientific societies have provided guidelines for the management of endocrine immune-related adverse events. However, guidelines recommendations differ according to the specific filed, particularly pertaining to recommendations for the timing of endocrine testing. In this position paper, a panel of experts of the Italian Association of Medical Oncology (AIOM), Italian Association of Medical Diabetologists (AMD), Italian Society of Diabetology (SID), Italian Society of Endocrinology (SIE), and Italian Society of Pharmacology (SIF) offers a critical multidisciplinary consensus for a clear, simple, useful, and easily applicable endocrine-metabolic assessment checklist for cancer patients on immunotherapy.

Abemaciclib pharmacology and interactions in the treatment of HR+/HER2- breast cancer: a critical review.

Abemaciclib (ABE) in combination with endocrine therapy represents the mainstay treatment for either endocrine-resistant metastatic or high-risk early-stage HR+/HER2- breast cancer patients. Hence, an adequate knowledge of this agent pharmacodynamic, pharmacokinetic, and of its drug-drug interactions (DDIs) is crucial for an optimal patients management. Additionally, ABE interference with food and complementary/alternative medicines should be taken into account in the clinical practice. Several online tools allow to freely check DDIs and can be easily consulted before prescribing ABE. According to one of this instruments, ABE display the lowest number of interactions among the available cyclin-dependent kinase 4/6 inhibitors. Still, clinicians should be aware that online tools cannot replace the technical datasheet of the drug as well as a comprehensive clinical assessment for each patient. Here we critically review the main pharmacological features of ABE, then focusing on its potential interactions with drugs, food, and alternative medicine, in order to provide a guide for its optimal use in the treatment of HR+/HER2- breast cancer patients.

Pharmacological features and drug interactions of abemaciclib Why was the review done? Abemaciclib, paired with hormone therapy, is a key treatment for breast cancer patients whose cancer cells respond to hormones but not to a protein called HER2. Understanding how this medication functions in the body, how it interacts with other drugs, and how the body processes it is crucial for providing optimal care. What did the authors do? The authors looked for published evidence about the way abemaciclib works into the body and about how it interacts with other drugs (including alternative medicines) or food. Then they summarized these findings. What did the authors find? Abemaciclib absorption, distribution, metabolism and excretion is well known and it is here described. What people eat and any alternative medications they take can affect how abemaciclib works. Online tools are available for doctors to check potential interactions between abemaciclib and other drugs a patient might be using. It's advisable for doctors to consult abemaciclib data sheet and use online tools before prescribing the drug. Notably, compared to similar treatments, abemaciclib has fewer interactions with other drugs. What does the review mean? This review delves into how abemaciclib works in the body and explore its potential interactions with other drugs, food, and alternative medicines. This information will aid doctors in using abemaciclib effectively for treating breast cancer patients.

TGF-ß mRNA levels in circulating extracellular vesicles are associated with response to anti-PD1 treatment in metastatic melanoma.

Introduction: Immune checkpoint inhibitors (ICIs) represent the standard therapy for metastatic melanoma. However, a few patients do not respond to ICIs and reliable predictive biomarkers are needed. Methods: This pilot study investigates the association between mRNA levels of programmed cell death-1 (PD-1) ligand 1 (PD-L1), interferon-gamma (IFN-γ), and transforming growth factor-ß (TGF-ß) in circulating extracellular vesicles (EVs) and survival in 30 patients with metastatic melanoma treated with first line anti-PD-1 antibodies. Blood samples were collected at baseline and RNA extracted from EVs; the RNA levels of PD-L1, IFN-γ, and TGF-ß were analysed by digital droplet PCR (ddPCR). A biomarker-radiomic correlation analysis was performed in a subset of patients. Results: Patients with high TGF-ß expression (cut-off fractional abundance [FA] >0.19) at baseline had longer median progression-free survival (8.4 vs. 1.8 months; p = 0.006) and overall survival (17.9 vs. 2.63 months; p = 0.0009). Moreover, radiomic analysis demonstrated that patients with high TGF-ß expression at baseline had smaller lesions (2.41 ± 3.27 mL vs. 42.79 ± 101.08 mL, p < 0.001) and higher dissimilarity (12.01 ± 28.23 vs. 5.65 ± 8.4; p = 0.018). Discussion: These results provide evidence that high TGF-ß expression in EVs is associated with a better response to immunotherapy. Further investigation on a larger patient population is needed to validate the predictive power of this potential biomarker of response to ICIs.

Pharmacological insights on novel oral selective estrogen receptor degraders in breast cancer.

The therapeutic landscape of estrogen receptor (ER)-positive breast cancer includes endocrine treatments with aromatase inhibitors (AIs), selective estrogen receptor modulators (SERMs), and selective estrogen receptor degraders (SERDs). Fulvestrant is the first approved SERD with proven efficacy and good tolerability in clinical practice. However, drug resistance, low receptor affinity, and parental administration stimulated the search for new oral SERDs opening a new therapeutic era in ER + breast cancer. Elacestrant is an orally bioavailable SERD that has been recently approved by the FDA for postmenopausal women with ER+, human epidermal growth factor receptor 2-negative (HER2-), estrogen receptor 1 (ESR1)-mutated advanced or metastatic breast cancer with disease progression following at least one line of endocrine therapy. Other molecules of the same class currently tested in clinical trials are amcenestrant, giredestrant, camizestrant, and imlunestrant. The current review article offers a detailed pharmacological perspective of this emerging drug class, which may help with their possible future clinical applications.

Clinical utility of Next Generation Sequencing of plasma cell-free DNA for the molecular profiling of patients with NSCLC at diagnosis and disease progression.

BACKGROUND: The present study evaluates the utility of NGS analysis of circulating free DNA (cfDNA), which incorporates small amounts of tumor DNA (ctDNA), at diagnosis or at disease progression (PD) in NSCLC patients. METHODS: Comprehensive genomic profiling on cfDNA by NGS were performed in NSCLC patients at diagnosis (if tissue was unavailable/insufficient) or at PD to investigate potential druggable molecular aberrations. Blood samples were collected as routinary diagnostic procedures, DNA was extracted, and the NextSeq 550 Illumina platform was used to run the Roche Avenio ctDNA Expanded Kit for molecular analyses. Gene variants were classified accordingly to the ESCAT score. RESULTS: A total of 106 patients were included in this study; 44 % of cases were requested because of tissue unavailability at the diagnosis and 56 % were requested at the PD. At least one driver alteration was observed in 62 % of cases at diagnosis. Driver druggable variants classified as ESCAT level I were detected in 34 % of patients, including ALK-EML4, ROS1-CD74, EGFR, BRAF, KRAS p.G12C, PI3KCA. In the PD group, most patients were EGFR-positive, progressing to a first line-therapy. Sixty-three percent of patients had at least one driver alteration detected in blood and 17 % of patients had a known biological mechanism of resistance allowing further therapeutic decisions. CONCLUSIONS: The present study confirms the potential of liquid biopsy to detect tumour molecular heterogeneity in NSCLC patients at the diagnosis and at PD, demonstrating that a significant number of druggable mutations and mechanisms of resistance can be detected by NGS analysis on ctDNA.

Expression of Circulating let-7e and miR-126 May Predict Clinical Remission in Patients With Crohn's Disease Treated With Anti-TNF-α Biologics.

BACKGROUND: The identification of new biomarkers predictive of response to antitumor necrosis factor alpha (anti-TNF-α) monoclonal antibodies remains an unmet medical need in Crohn's disease (CD) because a high percentage of patients show no clinical improvement after treatment or can lose response over time. MicroRNAs (miRNAs) can regulate inflammatory and immunological responses and were found to play a role in CD. METHODS: Baseline serum samples from 37 CD patients previously treated with infliximab or adalimumab, as per clinical practice, were obtained from the serum library at the Gastroenterology Unit of the University Hospital of Pisa, Italy. Patients were categorized as responders or nonresponders based on the following treatment outcomes: clinical remission at weeks 14 and 54 and endoscopic remission at week 54. The expression levels of a panel of selected miRNAs were analyzed by real-time polymerase chain reaction. Comparisons of miRNA expression between responders and nonresponders and statistical analyses were performed by MedCalc and GraphPad Prism software. Receiver operating characteristic curve analyses were calculated to evaluate the predictive performance of potential biomarkers. RESULTS: Patients in clinical remission at week 14 had a lower let-7e expression, whereas those in clinical remission at week 54 had lower levels of circulating miR-126 than nonresponders. The receiver operating characteristic curve analysis identified optimal cutoff values with assay sensitivity and specificity of 92.9% and 61.1%, for let-7e, and 62.5% and 83.3%, for miR-126, respectively. CONCLUSION: These results provide evidence that expression levels of circulating let-7e and miR-126 at baseline may predict clinical remission in CD patients treated with anti-TNF-α biologics.

We found that the baseline expression of 2 microRNAs (Let-7e and miR126) involved in inflammation and immune system regulation may predict short- and long-term clinical remission in CD patients treated with anti-TNF-α biologics, supporting clinicians in therapeutic decision-making.

Multidisciplinary management of HER2-positive breast cancer with brain metastases: An evidence-based pragmatic approach moving from pathophysiology to clinical data.

INTRODUCTION: About 30-50 % of stage IV HER2+ breast cancers (BC) will present brain metastases (BMs). Their management is based on both local treatment and systemic therapy. Despite therapeutic advances, BMs still impact on survival and quality of life and the development of more effective systemic therapies represents an unmet clinical need. MATERIALS AND METHODS: A thorough analysis of the published literature including ongoing clinical trials has been performed, investigating concepts spanning from the pathophysiology of tumor microenvironment to clinical considerations with the aim to summarize the current and future locoregional and systemic strategies. RESULTS: Different trials have investigated monotherapies and combination treatments, highlighting how the blood-brain barrier (BBB) represents a major problem hindering diffusion and consequently efficacy of such options. Trastuzumab has long been the mainstay of systemic therapy and over the last two decades other HER2-targeted agents including lapatinib, pertuzumab, and trastuzumab emtansine, as well as more recently neratinib, tucatinib, and trastuzumab deruxtecan, have been introduced in clinical practice after showing promising results in randomized controlled trials. CONCLUSIONS: We ultimately propose an evidence-based treatment algorithm for clinicians treating HER2 + BCs patients with BMs.

Polybrominated Diphenyl Ethers (PBDEs) and Human Health: Effects on Metabolism, Diabetes and Cancer.

There is increasing evidence of the role of endocrine disruptors (EDs) derived from commonly employed compounds for manufacturing and processing in altering hormonal signaling and function. Due to their prolonged half-life and persistence, EDs can usually be found not only in industrial products but also in households and in the environment, creating the premises for long-lasting exposure. Polybrominated diphenyl ethers (PBDEs) are common EDs used in industrial products such as flame retardants, and recent studies are increasingly showing that they may interfere with both metabolic and oncogenic pathways. In this article, a multidisciplinary panel of experts of the Italian Association of Medical Diabetologists (AMD), the Italian Society of Diabetology (SID), the Italian Association of Medical Oncology (AIOM), the Italian Society of Endocrinology (SIE) and the Italian Society of Pharmacology (SIF) provides a review on the potential role of PBDEs in human health and disease, exploring both molecular and clinical aspects and focusing on metabolic and oncogenic pathways.

Comparison of digital PCR systems for the analysis of liquid biopsy samples of patients affected by lung and colorectal cancer.

BACKGROUND AND AIMS: Highly sensitive technologies are available for the molecular characterization of solid tumors, including digital PCR (dPCR). Liquid biopsy, based on the analysis of cell-free DNA (cfDNA), is often used to assess EGFR or RAS alterations in lung and colorectal cancers. Our study aimed to compare the results of two different dPCR platforms for the detection of mutations in cfDNA. METHODS: Plasma samples from lung and colorectal cancer patients collected as per routine procedures have been tested. cfDNA Was extracted from plasma, and samples were screened on the droplet digital PCR (ddPCR, BioRad) and solid dPCR QIAcuity (Qiagen). RESULTS: A total of 42 samples were analyzed, obtained from 20 Non-Small Cell Lung Cancer (NSCLC) patients carrying an EGFR or a KRAS mutation on tissue at diagnosis, and from 22 samples of colorectal cancer (CRC) patients, 10 of which presenting a KRAS mutation. EGFR mutation detection was 58.8% for ddPCR and 100% for dPCR (κ = 0.54; 95% CI, 0.37-0.71), compared to tissue results. The detection rate for RAS mutations was 72.7% for ddPCR and 86.4% for dPCR (κ = 0.34; 95% CI, 0.01-0.68), compared to tissue results. CONCLUSIONS: This study showed moderate agreement between dPCR and ddPCR. Sampling effect or threshold settings may potentially explain the differences in the cfDNA data between the two different platforms.

Corticosteroids in oncology: Use, overuse, indications, contraindications. An Italian Association of Medical Oncology (AIOM)/ Italian Association of Medical Diabetologists (AMD)/ Italian Society of Endocrinology (SIE)/ Italian Society of Pharmacology (SIF) multidisciplinary consensus position paper.

Corticosteroids (CSs) are widely used in oncology, presenting several different indications. They are useful for induction of apoptosis in hematological neoplasms, for management of anaphylaxis and cytokine release/hypersensitivity reaction and for the symptomatic treatment of many tumour- and treatment-related complications. If the employment of CSs in the oncological setting results in several benefits for patients and satisfaction for clinicians, on the other hand, many potential adverse events (AEs), both during treatment and after withdrawal of CSs, as well as the duality of the effects of these compounds in oncology, recommend being cautious in clinical practice. To date, several gray zones remain about indications, contraindications, dose, and duration of treatment. In this article, a panel of experts provides a critical review on CSs therapy in oncology, focusing on mechanisms of action and pharmacological characteristics, current and emerging therapeutic indications/contraindications, AEs related to CSs treatment, and the impact on patient outcome.

Concomitant administration of proton pump inhibitors does not significantly affect clinical outcomes in metastatic breast cancer patients treated with ribociclib.

BACKGROUND: Gastric pH changes by proton-pump-inhibitors (PPIs) were found to affect progression-free survival (PFS) in metastatic breast cancer (mBC) patients treated with palbociclib. The current study was aimed at investigating whether the same effect could occur in patients treated with ribociclib. PATIENTS AND METHODS: Patients with hormone-positive/HER-2-negative mBC candidates for first-line treatment with ribociclib were enrolled in this retrospective-cohort study. Patients were classified as "no concomitant PPIs" or "concomitant PPIs"; PPI administration covered the entire or not less than 2/3 of treatment with ribociclib. All clinical interventions were made according to clinical practice. RESULTS: A total of 128 patients were consecutively enrolled in the study; 78 belonged to the "no concomitant PPIs" group and 50 to the "concomitant PPIs" group. One hundred and six patients were endocrine-sensitive and received ribociclib and letrozole, while 22 were endocrine-resistant and were treated with ribociclib and fulvestrant. The most prescribed PPI was lansoprazole. According to PFS, patients taking PPIs had a PFS almost superimposable to those assuming ribociclib and endocrine therapy alone (35.3 vs. 49.2 months, p = 0.594). No difference in PFS was observed in estrogen-sensitive or estrogen-resistant mBC in the presence or absence of concomitant PPI treatment (p = 0.852). No correlation with adverse events was found including grade>2 hematological toxicities. CONCLUSIONS: The present study supports the hypothesis that the concomitant use of PPIs does not compromise the efficacy of ribociclib in a real-life setting.

The expanding family of c-Met inhibitors in solid tumors: a comparative analysis of their pharmacologic and clinical differences.

c-Met inhibitors are a class of drugs that include nonselective and selective molecules. These drugs can differ in terms of pharmacodynamic and pharmacokinetic properties that may be clinically relevant. c-Met inhibitors with high potency and selectivity may allow achieving optimal c-Met inhibition in c-Met-driven tumors while reducing unwanted off-target toxicities due to activation of multiple kinases. Nonselective drugs can instead be considered in tumors that also recognize other drivers (e.g., ALK, ROS, VEGF). Improved understanding of the clinical pharmacokinetics of c-Met inhibitors can help avoid drug-drug interactions and optimize schedules for continuous in vivo inhibition of c-Met phosphorylation. The current review article provides a detailed overview of the clinical pharmacology of molecules used in c-Met-driven tumors.

Diagnosis and treatment monitoring in breast cancer: how liquid biopsy can support patient management.

Imaging and tissue biopsies represent the current gold standard for breast cancer diagnosis and patient management. However, these practices are time-consuming, expensive and require invasive procedures. Moreover, tissue biopsies do not capture spatial and temporal tumor heterogeneity. Conversely, liquid biopsy, which includes circulating tumor cells, circulating free nucleic acids and extracellular vesicles, is minimally invasive, easy to perform and can be repeated during a patient's follow-up. Increasing evidence also suggests that liquid biopsy can be used to efficiently screen and diagnose tumors at an early stage, and to monitor changes in the tumor molecular profile. In the present review, clinical applications and prospects are discussed.

Pharmacological Basis of Breast Cancer Resistance to Therapies - An Overview.

Breast Cancer (BC) is a molecular heterogeneous disease and patients with similar clinico-pathological characteristics often display different response to treatment. Cellular processes, including uncontrolled cell-cycle, constitutive activation of signalling pathways and alterations in DNA-repair mechanisms are the main altered features in breast cancer. These cellular processes play significant roles in the emergence of resistance to therapies. The introduction of target therapies and immunotherapy significantly improved the survival of breast cancer patients. The incorporation of novel biomarkers together with the introduction of new therapeutic options may help to overcome treatment resistance. Molecular profiling promises to help in refine personalized treatment decisions and catalyse the development of further strategies when resistances inevitably occurs. This review provides a summary of genetic and molecular aspects of resistance mechanisms to available treatments for BC patients, and its clinical implications.

Gemcitabine Plus Nab-Paclitaxel Induces PD-L1 mRNA Expression in Plasma-Derived Microvesicles in Pancreatic Cancer.

Pancreatic ductal adenocarcinoma (PDAC) is a non-immunogenic tumor poorly responsive to immune checkpoint inhibitors. This study investigates the effect of 5-fluorouracil (5-FU), irinotecan, and oxaliplatin (FOLFIRINOX), and gemcitabine plus nab-paclitaxel (GEMnPAC) regimens on PD-L1 mRNA expression in plasma-derived microvesicles (MVs) in 50 PDAC patients. Plasma was collected before starting chemotherapy and after 3 months of treatment. mRNA was extracted from MVs, and PD-L1 expression was measured by digital droplet PCR. Twenty-eight patients were PD-L1 positive in MVs at baseline, of which 18 were in the GEMnPAC cohort and 10 in the FOLFIRINOX one. The amount of PD-L1 expression in MVs increased from baseline to 3 months of treatment in patients receiving GEMnPAC (median value 0.002 vs. 0.005; p = 0.01) compared to those treated with FOLFIRINOX (median 0.003 vs. 0.004; p = 0.97). The increase in PD-L1 mRNA expression in MVs was not related to tumor response (PR + SD: p = 0.08; PD: p = 0.28). Our findings demonstrate that GEMnPAC can increase PD-L1 mRNA expression in patient-derived circulating MVs, providing a rationale for testing the efficacy of this regimen in sequential or simultaneous combinations with immunotherapy in PDAC patients.

Clinical pharmacology and drug-drug interactions of lenvatinib in thyroid cancer.

Lenvatinib is a non-selective tyrosine kinase inhibitor (TKI) with high in vitro potency against vascular endothelial growth factor receptors. Although this drug is used to treat several cancer types, it is the most effective TKI used in patients with thyroid cancer. Lenvatinib is well tolerated and the most common adverse drug reactions can be adequately managed by dose adjustment. Particularly, blood pressure and cardiac function monitoring, as well as antihypertensive treatment optimization, may be required in patients treated with lenvatinib. Dose reduction should be taken into account in patients with body weight <60 kg or severe hepatic failure. No significant change in lenvatinib pharmacokinetics has been observed with other patient-related factors and very few data are available on lenvatinib pharmacogenetics. Lenvatinib can be administered orally regardless of food and no clinically relevant drug-drug interactions have been reported.

Pharmacology differences among proteasome inhibitors: Implications for their use in clinical practice.

Preclinical and clinical investigation on proteasome as a druggable target in cancer has led to the development of proteasome inhibitors (PIs) with different pharmacodynamic and pharmacokinetic properties. For example, carfilzomib has a better safety profile and a lower risk of clinically relevant drug-drug interactions than bortezomib, whereas ixazomib can be orally administered on a weekly basis due to a very long elimination half-life and high systemic exposure. The purpose of this review article is to elucidate the quantitative and qualitative differences in potency, selectivity, pharmacokinetics, safety and drug-drug interactions of clinically validated PIs to provide useful information for their clinical use in real life setting.

Blood-based PD-L1 analysis in tumor-derived extracellular vesicles: Applications for optimal use of anti-PD-1/PD-L1 axis inhibitors.

Monoclonal antibodies that inhibit the programmed cell death protein 1 axis (anti-PD-1/PD-L1) are part of a new pharmacological strategy aimed at reinforcing the immune response to cancer. Despite the success in several cancer types, a significant percentage of patients do not benefit from treatment with these drugs due to intrinsic or acquired resistance or the occurrence of immune-related adverse reactions. Assessment of PD-L1 expression in tumor tissues is currently used to predict drug response in the clinics; however, there is a growing interest in identifying blood-based biomarkers that, owing to the minimally-invasive nature, can allow a dynamic monitoring of drug response in daily clinical practice. In the current review article, we discuss whether the assessment of PD-L1 mRNA and protein levels in circulating extracellular vesicles may have the potential to predict the likelihood of tumor response to anti-PD-1/PD-L1 antibodies.