Antibiotic Abuse and Antimicrobial Resistance in Hospital Environment: A Retrospective Observational Comparative Study.

Background and Objectives: Antimicrobial resistance represents a serious problem, and it may be life-threatening in the case of severe hospital-acquired infections (HAI). Antibiotic abuse and multidrug resistance (MDR) have significantly increased this burden in the last decades. The aim of this study was to investigate the distribution and susceptibility rates of five selected bacterial species (E. coli, K. pneumoniae, P. aeruginosa, S. aureus and E. faecium) in two healthcare settings located in the Apulia region (Italy). Materials and Methods: Setting n.1 was a university hospital and setting n.2 was a research institute working on oncological patients. All the enrolled patients were diagnosed for bacterial HAI. The observation period was between August and September 2021. Clinical samples were obtained from several biological sources, in different hospital wards. Bacterial identification and susceptibility were tested by using the software VITEC 2 Single system. Results: In this study, a higher incidence of multi-drug-resistant K. pneumoniae was reported (42,2% in setting n.1 and 50% in setting n.2), with respect to the Italian 2019 statistics report (30.3%). All the isolates of E. faecium and S. aureus were susceptible to linezolid. All the bacterial isolates of P. aeruginosa and most of K. pneumoniae were susceptible to ceftazidime-avibactam. Amikacin and nitrofurantoin represented a good option for treating E. coli infections. Multidrug-resistant (MDR) P. aeruginosa, methicillin-resistant S. aureus (MRSA) and vancomycin-resistantE. faecium (VRE) had a lower incidence in the clinical setting, with respect to E. coli and K. pneumoniae. Conclusions: The data obtained in this study can support clinicians towards a rational and safe use of antibiotics for treating the infections caused by these resistant strains, to enhance the overall efficacy of the current antibiotic protocols used in the main healthcare environments.

Peripheral Neuropathy under Oncologic Therapies: A Literature Review on Pathogenetic Mechanisms.

Peripheral neurologic complications are frequent adverse events during oncologic treatments and often lead to dose reduction, administration delays with time elongation of the therapeutic plan and, not least, worsening of patients' quality of life. Experience skills are required to recognize symptoms and clinical evidences and the collaboration between different health professionals, in particular oncologists and hospital pharmacists, grants a correct management of this undesirable occurrence. Some classes of drugs (platinates, vinca alkaloids, taxanes) typically develop this kind of side effect, but the genesis of chemotherapy-induced peripheral neuropathy is not linked to a single mechanism. This paper aims from one side at summarizing and explaining all the scattering mechanisms of chemotherapy-induced peripheral neuropathy through a detailed literature revision, on the other side at finding new approaches to possible treatments, in order to facilitate the collaboration between oncologists, hematologists and hospital pharmacists.

miRNAs for the detection of multidrug resistance: overview and perspectives.

The goal of the present paper is to establish and validate the link between cancer diagnosis and therapy by microRNAs detection. The induction in vitro of some specific microRNAs after treatment with MDR ligands has been outlined. Starting from the results obtained by in vitro induction of MDCK and MDCK-MDR1 cells treated by a MDR1 ligand, a new scenario in the early diagnosis and chemotherapy could be disclosed. To corroborate this perspective a short overview on pancreatic cancer diagnosis and chemotherapeutic treatment has been reported.

The role of immune checkpoint inhibitors in the first-line treatment for patients with advanced biliary tract cancer: a systematic review and meta-analysis of randomized trials.

Background: We performed a systematic review and meta-analysis to further explore the impact of the addition of immunotherapy to gemcitabine-cisplatin as first-line treatment for advanced biliary tract cancer (BTC) patients. Methods: Literature research was performed, and hazard ratio values and 95% confidence intervals were calculated. Heterogeneity among studies was assessed using the tau-squared estimator ( τ 2 ) . The total Cochrane Q test (Q) was also assessed. The overall survival rate, objective response rate, and progression-free survival in the selected studies were assessed. Results: A total of 1,754 participants were included. Heterogeneity among the studies selected was found to be non-significant (p = 0.78; tau2 = 0, I2 = 0%). The model estimation results and the forest plot suggested that the test for the overall effect was significant (Z = -3.51; p< 0.01). Conclusion: The results of the current meta-analysis further confirm the role of immune checkpoint inhibitors plus gemcitabine-cisplatin as the new standard first-line treatment for advanced BTC patients. Systematic review registration: https://www.crd.york.ac.uk/prospero, identifier CRD42023488095.

The molecular tumor board as a step in cancer patient management: a southern Italian experience.

Introduction: The management of cancer patients follows a Diagnostic Therapeutic and Care Pathway (PDTA) approach, aimed at achieving the optimal balance between care and quality of life. To support this process, precision medicine and innovative technologies [e.g., next-generation sequencing (NGS)] allow rapid identification of genetic-molecular alterations useful for the design of PDTA-approved therapies. If the standard approach proves inadequate, the Molecular Tumor Board (MTB), a group comprising specialists from diverse disciplines, can step in to evaluate a broader molecular profile, proposing potential therapies beyond evidence levels I-II or considering enrolment in clinical trials. Our aim is to analyze the role of the MTB in the entire management of patients in our institute and its impact on the strategy of personalized medicine, particularly when all approved treatments have failed. Materials and methods: In alignment with European and national guidelines, a panel of clinicians and preclinical specialists from our institution was defined as the MTB core team. We designed and approved a procedure for the operation of this multidisciplinary group, which is the only one operating in the Puglia region. Results and discussion: In 29 months (2021-2023), we discussed and analyzed 93 patients. A total of 44% presented pathogenic alterations, of which 40.4% were potentially actionable. Only 11 patients were proposed for enrollment in clinical trials, treatment with off-label drugs, or AIFA (the Italian pharmaceutical agency for drugs)-5% funding. Our process indicators, time to analysis, and number of patient cases discussed are in line with the median data of other European institutions. Such findings underscore both the importance and usefulness of the integration of an MTB process into the care of oncology patients.

A real-world retrospective, observational study of first-line pembrolizumab plus chemotherapy for metastatic non-squamous non-small cell lung cancer with PD-L1 tumor proportion score < 50% (PEMBROREAL).

Introduction: The phase III Keynote-189 trial established a first-line treatment combining pembrolizumab with pemetrexed and platinum as a standard treatment for patients with stage IV non-small cell lung cancer (NSCLC) without known EGFR and ALK driver mutations and independent of programmed cell death ligand 1 (PD-L1) expression. However, in Italy, eligibility for the National Health Service payment program is limited to patients with PD-L1 <50%. The PEMBROREAL study assesses the real-world effectiveness and safety of pembrolizumab in patients eligible for the National Health Service payment program. Methods: PEMBROREAL is a retrospective, observational study on patients with NSCLC who started pembrolizumab combined with pemetrexed and platinum within the reimbursability time window, considered as December 2019 to December 2020. The primary endpoints were to assess progression-free survival (PFS) and overall survival (OS; using the Kaplan-Meier method), response to therapy, and tolerability. Results: Until February 2022, 279 patients (median follow-up: 19.7 months) have been observed. The median PFS was 8.0 months (95% confidence interval: 6.5-9.2). OS was not reached, but we can estimate a 12- to 24-month survival rate for the combined treatment: 66.1% and 52.5%, respectively. PD-L1 expression and Eastern Cooperative Group (ECOG) Performance Status were both associated with PFS and OS. Overall, only 44.4% of patients reported an adverse event, whereas toxicity led to a 5.4% discontinuation rate. Conclusion: The results of the PEMBROREAL study have shown that the combined treatment of pembrolizumab with pemetrexed and platinum is effective for metastatic non-squamous NSCLC, even for patients with PD-L1 levels below 50%, despite the differences in patient demographics and pathological features compared to the Keynote-189 study. The adverse events reported during the study were more typical of chemotherapy treatment rather than immunotherapy, and physicians were able to manage them easily.

Real-World Safety and Outcome of First-Line Pembrolizumab Monotherapy for Metastatic NSCLC with PDL-1 Expression ≥ 50%: A National Italian Multicentric Cohort ("PEMBROREAL" Study).

Results from the phase III Keynote-024 clinical trial established pembrolizumab monotherapy as the first-line standard of care for patients with metastatic NSCLC who have PD-L1 expression ≥ 50%, EGFR, and ALK wild-type tumors. However, given the differences between patients treated in routine clinical practice and those treated in a clinical trial, real-world data are needed to confirm the treatment benefit in standard practice. Given the lack of data on large cohorts of patients with long follow-ups, we designed an observational retrospective study of patients with metastatic NSCLC who were treated with pembrolizumab, starting from its reimbursement eligibility until December 2020. The primary endpoints were PFS and OS, determined using the Kaplan-Meier method. Response and safety were also evaluated. We followed 880 patients (median follow-up: 35.1 months) until February 2022. Median PFS and OS were 8.6 months (95% CI: 7.6-10.0) and 25.5 months (95% CI: 21.8-31.6), respectively. We also found that ECOG PS, PD-L1 expression, and habitual smoking were prognostic factors for PFS, while age, sex, ECOG PS, habitual smoking and histology had an impact on OS. Multivariable analysis confirms the prognostic role of PD-L1 for PFS and of ECOG for both PFS and OS. 39.9% of patients reported an adverse event, but only 6.3% of patients discontinued therapy due to toxicity. Our results suggest a long-term benefit of pembrolizumab in the first-line setting, as well as a safety profile consistent with the results of Keynote-024. Many collected variables appear to influence clinical outcome, but results from these exploratory unadjusted analyses should be interpreted with caution.

Carcinogenesis of pancreatic adenocarcinoma: precursor lesions.

Pancreatic adenocarcinoma displays a variety of molecular changes that evolve exponentially with time and lead cancer cells not only to survive, but also to invade the surrounding tissues and metastasise to distant sites. These changes include: genetic alterations in oncogenes and cancer suppressor genes; changes in the cell cycle and pathways leading to apoptosis; and also changes in epithelial to mesenchymal transition. The most common alterations involve the epidermal growth factor receptor (EGFR) gene, the HER2 gene, and the K-ras gene. In particular, the loss of function of tumor-suppressor genes has been documented in this tumor, especially in CDKN2a, p53, DPC4 and BRCA2 genes. However, other molecular events involved in pancreatic adenocarcinoma pathogenesis contribute to its development and maintenance, specifically epigenetic events. In fact, key tumor suppressors that are well established to play a role in pancreatic adenocarcinoma may be altered through hypermethylation, and oncogenes can be upregulated secondary to permissive histone modifications. Indeed, factors involved in tumor invasiveness can be aberrantly expressed through dysregulated microRNAs. This review summarizes current knowledge of pancreatic carcinogenesis from its initiation within a normal cell until the time that it has disseminated to distant organs. In this scenario, highlighting these molecular alterations could provide new clinical tools for early diagnosis and new effective therapies for this malignancy.

The Role of Stakeholders' Understandings in Emerging Antimicrobial Resistance: A One Health Approach.

The increasing misuse of antibiotics in human and veterinary medicine and in agroecosystems and the consequent selective pressure of resistant strains lead to multidrug resistance (AMR), an expanding global phenomenon. Indeed, this phenomenon represents a major public health target with significant clinical implications related to increased morbidity and mortality and prolonged hospital stays. The current presence of microorganisms multi-resistant to antibiotics isolated in patients is a problem because of the additional burden of disease it places on the most fragile patients and the difficulty of finding effective therapies. In recent decades, international organizations like the World Health Organization (WHO) and the European Centre for Disease Prevention and Control (ECDC) have played significant roles in addressing the issue of AMR. The ECDC estimates that in the European Union alone, antibiotic resistance causes 33,000 deaths and approximately 880,000 cases of disability each year. The epidemiological impact of AMR inevitably also has direct economic consequences related not only to the loss of life but also to a reduction in the number of days worked, increased use of healthcare resources for diagnostic procedures and the use of second-line antibiotics when available. In 2015, the WHO, recognising AMR as a complex problem that can only be addressed by coordinated multi-sectoral interventions, promoted the One Health approach that considers human, animal, and environmental health in an integrated manner. In this review, the authors try to address why a collaboration of all stakeholders involved in AMR growth and management is necessary in order to achieve optimal health for people, animals, plants, and the environment, highlighting that AMR is a growing threat to human and animal health, food safety and security, economic prosperity, and ecosystems worldwide.

LC-MS/MS Analysis on Infusion Bags and Filled Syringes of Decitabine: New Data on Physicochemical Stability of an Unstable Molecule.

Many anticancer drugs are reported to have low physicochemical stability after dilution; therefore, producers impose short times from reconstitution, dilution, and the end of administration. The precariousness of cancer patients' health in real-life experience within cancer hospitals often forces delays in the drug administration with respect to the standard treatment schedule timing, because of acute toxicities or the need to postpone a control analysis before administration. The public health costs for discarded anticancer drugs due to administration interruptions can be avoided, thanks to independent analytical studies, which integrate the producer's data reported in the technical sheet, referring to the real conditions of preparation in a sterile atmosphere under a cabin in a laboratory dedicated to handling cytotoxic drugs in controlled conditions of temperature, pressure, and particulate contamination. Decitabine is apparently an unstable molecule, whose reported stability is only 3 h at 2-8 °C when diluted, while the mother solution must be immediately used or, otherwise, discarded. This study has investigated the physicochemical stability of decitabine both in diluted infusion bags and in sterile water reconstituted syringes at 4 °C for 0, 24, 48, and 72 h. In all performed studies, the stability-indicating method involves, for the first time, the use of liquid chromatography-tandem mass spectrometry analysis. Unexpectedly, both diluted and reconstituted solutions of decitabine are more stable than previously reported data, with a 48 h-long physicochemical stability at 2-8 °C and protected from light.

Immunotherapy for Hepatocellular Carcinoma: New Prospects for the Cancer Therapy.

Hepatocellular carcinoma (HCC) is the fourth leading cause of cancer-related death worldwide. HCC patients may benefit from liver transplantation, hepatic resection, radiofrequency ablation, transcatheter arterial chemoembolization, and targeted therapies. The increased infiltration of immunosuppressive immune cells and the elevated expression of immunosuppressive factors in the HCC microenvironment are the main culprits of the immunosuppressive nature of the HCC milieu. The immunosuppressive tumor microenvironment can substantially attenuate antitumoral immune responses and facilitate the immune evasion of tumoral cells. Immunotherapy is an innovative treatment method that has been promising in treating HCC. Immune checkpoint inhibitors (ICIs), adoptive cell transfer (ACT), and cell-based (primarily dendritic cells) and non-cell-based vaccines are the most common immunotherapeutic approaches for HCC treatment. However, these therapeutic approaches have not generally induced robust antitumoral responses in clinical settings. To answer to this, growing evidence has characterized immune cell populations and delineated intercellular cross-talk using single-cell RNA sequencing (scRNA-seq) technologies. This review aims to discuss the various types of tumor-infiltrating immune cells and highlight their roles in HCC development. Besides, we discuss the recent advances in immunotherapeutic approaches for treating HCC, e.g., ICIs, dendritic cell (DC)-based vaccines, non-cell-based vaccines, oncolytic viruses (OVs), and ACT. Finally, we discuss the potentiality of scRNA-seq to improve the response rate of HCC patients to immunotherapeutic approaches.

Pharmacotherapy in Mast Cell Leukemia.

INTRODUCTION: Mast cell leukemia (MCL) is one of the most aggressive forms of Systemic Mastocytosis (SM), a complex family of rare diseases, for which standard therapies are very few. MCL represents only <1% cases of SM and this is the reason why there are no specific clinical trials to better explore this disease. As a consequence, MCL is treated and grouped within other forms of SM, being all KIT-driven diseases; however, its KIT dysregulation leads to uncontrolled activation of mast cells (MCs), which correlates with forms of myeloid acute leukemia (AML). AREAS COVERED: Different therapeutic approaches can be followed in the treatment of MCL. The authors look at both symptomatic therapies along with other approaches including targeted therapy. Further, the authors provide their expert opinion. EXPERT OPINION: In the scenario of mast cell leukemia treatment, the key approach to achieve clinical results is, more than other similar pathologies, personalizing the therapy. It could be interesting or desirable to introduce for instance KIT mutant forms as minor criteria for the diagnosis of advanced SM, considering the small patient population with MCL and the relatively large panel of activating mutations for KIT and other important proteins involved in MCs' regulation.

An evaluation of masitinib for treating systemic mastocytosis.

Introduction: Systemic Mastocytosis (SM) is a complex family of rare diseases, against which pharmacological therapies are still very few. It is a c-kit driven disease, whose disregulation leads to uncontrolled activation and proliferation of mast cells (MCs) with consequent release of effector molecules which are responsible for its clinical manifestations. Areas covered: Masitinib is a relatively new potential drug against SM and its chemical structure strictly derives from imatinib, the first tyrosine kinase inhibitor which entered the pharmaceutical market about 15 years ago. In this review, the authors present masitinib in all its properties, from chemistry to pharmacology and toxicity to its potential clinical application in SM, focusing the discussion on the few clinical trials in which it has been involved, with a particular attention on the still open challenge to determine how to measure the response to therapy. Expert opinion: In spite of their similarity in chemistry and biological activity against submolecular targets, masitinib is much more selective towards c-kit receptors than other tyrosine kinases, such as Bcl-Abl. Furthermore, its ability to inhibit degranulation, cytokine production and MCs migration from bone marrow gives it a great chance to become an important therapeutic option for selected SM patients.

An updated patent review on P-glycoprotein inhibitors (2011-2018).

INTRODUCTION: P-glycoprotein is a complex ATP-ase transporter involved in physiological and pathological functions. In particular, it is involved in the onset of multidrug resistance in cancer, in ocular disease, Chronic Rhinosinusitis, CNS diseases such as Alzheimer, Parkinson, and epilepsy. One of the aims of clinicians and pharmacologists is to monitor P-gp activity through the inhibitors and to use its activity and/or expression in physiological barriers for the early diagnosis of several pathologies. Considering P-glycoprotein activity, several substrates have been characterized but the challenge is to design 'pure' P-glycoprotein inhibitors. AREAS COVERED: P-glycoprotein inhibitors display a large spectrum of activities. Here the contents of patents focused on the role of P-glycoprotein inhibitor in modulating MDR in cancer, in bioavailability, in ocular disease and Chronic Rhinosinusitis are reported. EXPERT OPINION: The use of P-glycoprotein inhibitor sic et simpliciter, or in coadministration with therapeutic agents, for ocular disease, and Chronic Rhinosinusitis is promising and could be suggested for additional trials. By contrast, the bioavailability of the coadministrated drugs, increased by P-glycoprotein inhibitor, deserves a wider discussion, in particular on the pharmacokinetic aspect of both P-glycoprotein inhibitor and the coadministered drug.

Strategies to Improve Cancer Immune Checkpoint Inhibitors Efficacy, Other Than Abscopal Effect: A Systematic Review.

Despite that the impact of immune checkpoint inhibitors on malignancies treatment is unprecedented, a lack of response to these molecules is observed in several cases. Differently from melanoma and non-small cell lung cancer, where the use of immune checkpoint inhibitors results in a high efficacy, the response rate in other tumors, such as gastrointestinal cancers, breast cancer, sarcomas, and part of genitourinary cancers remains low. The first strategy evaluated to improve the response rate to immune checkpoint inhibitors is the use of predictive factors for the response such as PD-L1 expression, tumor mutational burden, and clinical features. In addition to the identification of the patients with a higher expression of immune checkpoint molecules, another approach currently under intensive investigation is the use of therapeutics in a combinatory manner with immune checkpoint inhibitors in order to obtain an enhancement of efficacy through the modification of the tumor immune microenvironment. In addition to the abscopal effect induced by radiotherapy, a lot of studies are evaluating several drugs able to improve the response rate to immune checkpoint inhibitors, including microbiota modifiers, drugs targeting co-inhibitory receptors, anti-angiogenic therapeutics, small molecules, and oncolytic viruses. In view of the rapid and extensive development of this research field, we conducted a systematic review of the literature identifying which of these drugs are closer to achieving validation in the clinical practice.

Oxaliplatin-Based Intra-arterial Chemotherapy in Colo-Rectal Cancer Liver Metastases: A Review from Pharmacology to Clinical Application.

Liver metastases (LM) are often consequences of colo-rectal cancer (CRC)and the majority of patients have unresectable LM. Oxaliplatin-based intravenous chemotherapy represents the gold standard treatment for CRC. Intravenous oxaliplatin has several side effects i.e., nephrologic, hematologic and neurological toxicity. Moreover, hepatic arterial infusion (HAI) of antitumor drugs deeply modifies the treatment of LMCRC due to the knowledge that LM are perfused by the hepatic artery network, whereas healthy tissue is perfused by the portal vein. Therefore, oxaliplatin-based HAI becomes an interesting possibility to treat LMCRC. The aim of this review is to shed light on the important impact of the oxaliplatin-based chemotherapy from a non-conventional clinical point of view, considering that, being universally accepted its antitumor effect if administered intravenously, fragmentary information are known about its clinical applications and benefits deriving from intra-arterial administration in loco-regional chemotherapy.

Cost-utility and budget impact analyses of the use of NEPA for chemotherapy-induced nausea and vomiting prophylaxis in Italy.

OBJECTIVE: To evaluate the efficiency of resources allocation and sustainability of the use of netupitant+palonosetron (NEPA) for chemotherapy-induced nausea and vomiting (CINV) prophylaxis assuming the Italian National Health Service (NHS) perspective. A published Markov model was adapted to assess the incremental cost-utility ratio of NEPA compared with aprepitant (APR) + palonosetron (PALO), fosaprepitant (fAPR) + PALO, APR + ondansetron (ONDA), fAPR + ONDA in patients receiving a highly emetogenic chemotherapy (HEC) and with APR + PALO and fAPR + PALO in patients receiving a moderately emetogenic chemotherapy (MEC). SETTING: Oncology hospital department in Italy. METHODS: A Markov model was used to determine the impact of NEPA on the budget of the Italian NHS on a 5-day time horizon, corresponding to the acute and delayed CINV prophylaxis phases. Direct medical costs considered were related to antiemetic drugs, adverse events management, CINV episodes management. Clinical and quality of life data referred to previously published works. The budget impact analysis considered the aforementioned therapies plus PALO alone (for HEC and MEC) on a 5-year time horizon, comparing two scenarios: one considering the use of NEPA and one not considering its use. PRIMARY AND SECONDARY OUTCOME MEASURES: Incremental cost per quality adjusted life year (QALY) and differential economic impact for the Italian NHS between the two scenarios considered. RESULTS: NEPA is more effective and less expensive (dominant) compared with APR + PALO (for HEC and MEC), fAPR + PALO (for HEC and MEC), APR + ONDA (for HEC), fAPR + ONDA (for HEC). The use of NEPA would lead to a 5-year cost decrease of €63.7 million (€42.7 million for HEC and €20.9 million for MEC). CONCLUSIONS: NEPA allows an efficient allocation of resources for the Italian NHS and it is sustainable, leading to a cost decrease compared with a scenario which does not consider its use.

Immunotherapeutic approaches for hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is a cancer with a high mortality rate due to the fact that the diagnosis usually occurs at anadvanced stage. Even in case of curative surgical treatment, recurrence is common. Sorafenib and regorafenib are the only therapeutic agents that have been demonstrated to be effective in advanced HCC, thus novel curative approaches are urgently needed. Recent studies focus on the role of immune system in HCC. In fact, the unique immune response in the liver favors tolerance, which can represent a real challenge for conventional immunotherapy in these patients. Spontaneous immune responses against tumor antigens have been detected, and new immune therapies are under investigation: dendritic cell vaccination, immune-modulator strategy, and immune checkpoint inhibition. In recent years different clinical trials examining the use of immunotherapy to treat HCC have been conducted with initial promising results. This review article will summarize the literature data concerning the potential immunotherapeutic approaches in HCC patients.

Total and not bevacizumab-bound vascular endothelial growth factor as potential predictive factors to bevacizumab-based chemotherapy in colorectal cancer.

AIM: To identify suitable biomarkers of response to bevacizumab (BV) - it remains an open question. The measurement of serum vascular endothelial growth factor (VEGF) has been proposed as a predictive factor for this drug, even if literature data are contradictory. METHODS: We prospectively evaluated the role of BV, total and not BV-bound VEGF and angiopoietin-2 (Ang-2) serum levels as potential predictive factors of response for BV in combination with an oxaliplatin-based chemotherapy. BV, Ang-2, total and not BV-bound VEGF levels were measured at baseline, before 2(nd) and 5(th) cycle of oxaliplatin-based chemotherapy in 20 consecutive metastatic colorectal cancer patients. RESULTS: Results were correlated to response to treatment. Variability in BV levels have been found, with decreased level in less responding patients. In particular, the concentration of BV increased of 3.96 ± 0.69 folds in serum of responsive patients after 3 more cycles of therapy compared to those with stable or progressive disease with a 0.72 ± 0.25 and 2.10 ± 0.13 fold increase, respectively. The determination of free and total VEGF demonstrated that the ratio between the two values, evaluated immediately before the 2(nd) and the 5(th) cycle of therapy, decreased from 26.65% ± 1.33% to 15.50% ± 3.47% in responsive patients and from 53.41% ± 4.75 to 34.95% ± 2.88% in those with stable disease. Conversely, in those with progression of disease, the ratio showed the opposite behavior coming up from 25.99% ± 5.23% to 51.71% ± 5.28%. The Ang-2 levels did not show any relationship. CONCLUSION: Our data show that the ratio of not BV-bound VEGF to total VEGF serum and BV plasma concentrations for predicting the response to BV plus oxaliplatin-based chemotherapy could be a promising biomarker of response to BV.