Association between antibiotic-immunotherapy exposure ratio and outcome in metastatic non small cell lung cancer

Gut Microbiota Are a Novel Source of Biomarkers for Immunotherapy in Non-Small-Cell Lung Cancer (NSCLC)

Despite the recent availability of immune checkpoint inhibitors, not all patients affected by Non-Small-Cell Lung Cancer (NSCLC) benefit from immunotherapy. The reason for this variability relies on a variety of factors which may allow for the identification of novel biomarkers. Presently, a variety of biomarkers are under investigation, including the PD1/PDL1 axis, the tumor mutational burden, and the microbiota. The latter is made by all the bacteria and other microorganisms hosted in our body. The gut microbiota is the most represented and has been involved in different physiological and pathological events, including cancer. In this light, it appears that all conditions modifying the gut microbiota can influence cancer, its treatment, and its treatment-related toxicities. The aim of this review is to analyze all the conditions influencing the gut microbiota and, therefore, affecting the response to immunotherapy, iRAEs, and their management in NSCLC patients. The investigation of the landscape of these biological events can allow for novel insights into the optimal management of NSCLC immunotherapy.

Association of antibiotic treatment with survival outcomes in treatment-naïve melanoma patients receiving immune checkpoint blockade

PURPOSE

The interaction of gut microbiome and immune system is being studied with increasing interest. Disturbing factors, such as antibiotics may impact the immune system via gut and interfere with tumor response to immune checkpoint blockade (ICB).

METHODS

In this multicenter retrospective cohort study exclusively treatment-naïve patients with cutaneous or mucosal melanoma treated with first-line anti-PD-1 based ICB for advanced, non-resectable disease between 06/2013 and 09/2018 were included. Progression-free (PFS), and overall survival (OS) according to antibiotic exposure (within 60 days prior to ICB and after the start of ICB vs. no antibiotic exposure) were analyzed. To account for immortal time bias, data from patients with antibiotics during ICB were analyzed separately in the time periods before and after start of antibiotics.

RESULTS

Among 578 patients with first-line anti-PD1 based ICB, 7% of patients received antibiotics within 60 days prior to ICB and 19% after starting ICB. Antibiotic exposure prior to ICB was associated with worse PFS (adjusted HR 1.75 [95% CI 1.22-2.52]) and OS (adjusted HR 1.64 [95% CI 1.04-2.58]) by multivariate analysis adjusting for potential confounders. The use of antibiotics after the start of ICB had no effect on either PFS (adjusted HR 1.19; 95% CI 0.89-1.60) or OS (adjusted HR 1.08; 95% CI 0.75-1.57).

CONCLUSIONS

Antibiotic exposure within 60 days prior to ICB seems to be associated with worse PFS and OS in melanoma patients receiving first-line anti-PD1 based therapy, whereas antibiotics after the start of ICB do not appear to affect PFS or OS.

Gut microbiota and dietary intervention: affecting immunotherapy efficacy in non-small cell lung cancer

Non-small cell lung cancer (NSCLC) accounts for 80-85% of all lung cancers. In recent years, treatment with immune checkpoint inhibitors (ICIs) has gradually improved the survival rate of patients with NSCLC, especially those in the advanced stages. ICIs can block the tolerance pathways that are overexpressed by tumor cells and maintain the protective activity of immune system components against cancer cells. Emerging clinical evidence suggests that gut microbiota may modulate responses to ICIs treatment, possibly holding a key role in tumor immune surveillance and the efficacy of ICIs. Studies have also shown that diet can influence the abundance of gut microbiota in humans, therefore, dietary interventions and the adjustment of the gut microbiota is a novel and promising treatment strategy for adjunctive cancer therapy. This review comprehensively summarizes the effects of gut microbiota, antibiotics (ATBs), and dietary intervention on the efficacy of immunotherapy in NSCLC, with the aim of informing the development of novel strategies in NSCLC immunotherapy.

Association of antibiotic exposure with survival in patients with extensive-stage small cell lung cancer receiving immune checkpoint inhibitor therapy

BACKGROUND

Immune checkpoint inhibitors (ICIs) have dramatically shifted the therapeutic paradigm of extensive-stage small cell lung cancer (ES-SCLC). Antibiotic (ATB) exposure before or during ICI therapy can harm the integrity of the gut microbiome and lead to intestinal dysbiosis, which has a profoundly negative impact on the treatment response for various malignancies. Whether this is applicable to ES-SCLC remains unclear.

METHODS

We retrospectively reviewed the electronic medical records of all patients diagnosed with ES-SCLC who were treated with ICI-based immunotherapies from July 2019 to December 2020 at Shandong Cancer Hospital and Institute, China. Outcomes with the use of ATBs before or after the first infusion of ICI, including progression-free survival (PFS) and overall survival (OS), were investigated using the Kaplan-Meier method. Multivariate analyses were also conducted using a Cox proportional hazards model.

RESULTS

A total of 214 patients were included, among whom 41 (19.2%) received ATBs within 2 months before or after the first initiation of ICI therapy and were assigned to the ATB group. The ATB group showed a shorter median PFS (4.3 vs. 6.3 months; HR = 1.43, 95% CI: 0.97-2.11; p = 0.043) and a significantly shorter median OS (6.9 vs. 13 months; HR = 1.47, 95% CI: 0.98-2.20; p = 0.033) than the non-ATB group. In the multivariate analysis, ATB exposure was markedly associated with worse PFS (HR = 1.47, 95% CI: 1.03-2.09, p = 0.035) and OS (HR = 1.46, 95% CI: 1.01-2.11, p = 0.043).

CONCLUSIONS

Our results demonstrate that ATB exposure was significantly associated with worse survival in ES-SCLC patients who received ICI therapy.

Analysis of prognostic factors affecting immune checkpoint inhibitor therapy in tumor patients exposed to antibiotics

Objective

Meta-analysis was performed to evaluate the prognostic factors in tumor patients treated with immune checkpoint inhibitors (ICIs) under antibiotic exposure.

Method

Literature on the effect of antibiotics on the prognosis of tumor patients receiving ICIs was retrieved from Pubmed, Cochrane Library, EMbase, EBSCO Evidence-Based Medicine Database, China Biomedical Literature Database (CBM), and China National Knowledge Network (CNKI), and relevant influencing factors were extracted. Meta-analysis of efficacy was performed using RevMan 5.4 software.

Results

A total of nine studies for 1,677 patients were included. The meta-analysis results showed that, in terms of progression-free survival, gender (male vs. female), Eastern Cooperative Oncology Group performance status (ECOG PS) (1-2 vs. 0), history of another cancer (yes vs. no), liver metastasis (yes vs. no), antibiotics (within the previous 2 months), PD-L1 (1%-49%), and PD-L1 (≥50%) factors are associated with progression-free survival in patients treated with ICIs under antibiotic exposure. In terms of overall survival, gender (male vs. female), ECOG score (1-2 vs. 0), history of another cancer (yes vs. no), brain metastasis (yes vs. no), liver metastasis (yes vs. no), radiation (within the previous 3 months), antibiotics (within the previous 2 months), PD-L1 (1%-49%), and PD-L1 (≥50%) factors are associated with overall survival in patients with antibiotic exposure receiving ICIs for tumor treatment.

Conclusion

Gender, ECOG score, history of another cancer, brain metastasis, liver metastasis, radiation (within the previous 3 months), antibiotics (within the previous 2 months), PD-L1 (1%-49%), and PD-L1 (≥50%) were associated with clinical benefit in patients with antibiotic exposure receiving ICIs for tumor treatment. Based on the above-mentioned factors, clinicians can screen cancer patients who receive ICIs under antibiotic exposure and rationally use antibiotics and ICIs in combination.

Analysis of the relation between adverse events and overall survival in patients treated with pembrolizumab as a first-line treatment for metastatic NSCLC

BACKGROUND

Many trials supported pembrolizumab as a first-line monotherapy to significantly improve overall survival (OS) in selected patients with previously untreated metastatic Non-Small Cell Lung Cancer (mNSCLC) and a PD-L1 TPS of ≥50% without EGFR/ALK mutations. The aim of this study was to reveal the correlation between OS and adverse events in real-world settings after 42 months.

METHODS

This retrospective observational study involved 98 patients with mNSCLC, TPS ≥ 50%, and no EGFR/ALK aberrations. Patients were treated with pembrolizumab (200 mg q3w) as a first-line treatment. Clinical data, including PD-L1 expression, Performance Status (ECOG-PS), treatment duration, toxicity, and outcomes were retrieved from local electronic medical records and from the Italian Regulatory Agency Registry.

RESULTS

The cohort's main characteristics were as follows: median age 73 [44-89] years, 64.3% were male and 35.7% were female, an ECOG-PS score of 0 (n = 73) and 1 or 2 (n = 25), and a PD-L1 > 90% in 29.6% of patients. The entire cohort had stage IV NSCLC at diagnosis. The median number of cycles was 8.5 at a median follow-up of 13 months. The median OS of 13.6 months (95% CI: 11.7-NA) was not influenced by sex and PD-L1, but was significantly associated with ECOG-PS (p = 0.02). Immune-Related Adverse Events (irAEs) occurred in 77.5% of patients (30.1% cutaneous, 27.5% gastrointestinal, and 20.4% endocrinological), but no grade 4 or 5 irAEs were identified. Patients experiencing any type of toxicity had a significantly longer median OS (20.39 months, 95% CI: 13.08-NA) than those with no toxicities (6.46 months, 95% CI: 1.41-NA, p = 0.006).

CONCLUSION

The percentage of irAEs detected was comparable to that reported in KEYNOTE-024 and KEYNOTE-042. These real-world findings demonstrated the significant correlation between OS and cutaneous toxicities.

Short- and Long-term Repercussions of Vancomycin on Immune Surveillance and the Efficacy of Antitumor Treatments

ABSTRACT

Although antibiotic is a major contributor to shifts in the intestinal flora that may persist for up to several months after cessation, it is now increasingly recognized that its prescription may differentially influence clinical outcome of different anticancer treatments. Intense clinical and basic research efforts aim then at gaining sufficient insights about how the cooperative action between the intestinal ecosystem and immune surveillance modulates the efficacy of anticancer treatments. In this review, we summarize multiple levels of knowledge between vancomycin exposure, the gut microbiota, and a meaningful therapeutic response. Furthermore, we discuss the mode of action of antibiotic therapy that is prescribed for prophylaxis of bacteremia and neutropenia and outline the opportunity for judiciously improving the efficacy of anticancer drugs.

Effect of antimicrobial therapy on progression-free survival of immunotherapy and chemo-/immunotherapy in patients with non-small cell lung cancer

BACKGROUND

The choice between immunotherapy with a checkpoint inhibitor (CPI) and chemo-/immunotherapy (CIT) in patients with NSCLC stage IV is often discussed. There are some data that the effect of CPI therapy is impaired by antimicrobial therapy (AMT). Little is known about the influence of AMT on CIT.

PATIENTS AND METHODS

We retrospectively analysed 114 patients (age 68 ± 8.5 years) with NSCLC stage IV. Patients were treated according to the guidelines with either CPI alone (pembrolizumab, nivolumab, atezolizumab, cemiplimab) or CIT (Carboplatin/Pemetrexed/Pembrolizumab, Carboplatin/Paclitaxel/Pembrolizumab). We registered patients' characteristics including presence and timing of AMT. Group 1 consisted of 42 patients with AMT in the month before CPI or CIT, group 2 were 49 patients with AMT during CPI or CIT, and group 3 were 64 patients without AMT and CPI or CIT.

RESULTS

Group 1-3 showed comparable patients characteristics. Using cox-regression analysis, we found that AMT in the month before CPI resulted in a decreased progression-free survival (PFS) compared to patients with CPI and no AMT (14 ± 1.02 vs. 4 ± 1.02 months, p = 0.002, 95% CI 1.88-9). In patients, who were treated with CIT, there was no difference in PFS in those with or without AMT in the month before therapy (10 ± 2.5 vs. 6 ± 1.2 months, p = 0.7). Interestingly, AMT during CIT or CPI therapy showed no effect on PFS.

CONCLUSIONS

In a real-life setting, we found that AMT reduces PFS when given in the month before CIT therapy. AMT before or during CIT does not seem to influence PFS. As a consequence, AMT before start of therapy might be a factor that could lead to a preference of CIT instead of CPI in NSCLC stage IV patients.

A systematic review and meta-analysis evaluating the impact of antibiotic use on the clinical outcomes of cancer patients treated with immune checkpoint inhibitors

Background

Immune checkpoint inhibitors (ICIs) have considerably improved patient outcomes in various cancer types, but their efficacy remains poorly predictable among patients. The intestinal microbiome, whose balance and composition can be significantly altered by antibiotic use, has recently emerged as a factor that may modulate ICI efficacy. The objective of this systematic review and meta-analysis is to investigate the impact of antibiotics on the clinical outcomes of cancer patients treated with ICIs.

Methods

PubMed and major oncology conference proceedings were systematically searched to identify all studies reporting associations between antibiotic use and at least one of the following endpoints: Overall Survival (OS), Progression-Free Survival (PFS), Objective Response Rate (ORR) and Progressive Disease (PD) Rate. Pooled Hazard Ratios (HRs) for OS and PFS, and pooled Odds Ratios (ORs) for ORR and PD were calculated. Subgroup analyses on survival outcomes were also performed to investigate the potential differential effect of antibiotics according to cancer types and antibiotic exposure time windows.

Results

107 articles reporting data for 123 independent cohorts were included, representing a total of 41,663 patients among whom 11,785 (28%) received antibiotics around ICI initiation. The pooled HRs for OS and PFS were respectively of 1.61 [95% Confidence Interval (CI) 1.48-1.76] and 1.45 [95% CI 1.32-1.60], confirming that antibiotic use was significantly associated with shorter survival. This negative association was observed consistently across all cancer types for OS and depending on the cancer type for PFS. The loss of survival was particularly strong when antibiotics were received shortly before or after ICI initiation. The pooled ORs for ORR and PD were respectively of 0.59 [95% CI 0.47-0.76] and 1.86 [95% CI 1.41-2.46], suggesting that antibiotic use was significantly associated with worse treatment-related outcomes.

Conclusion

As it is not ethically feasible to conduct interventional, randomized, controlled trials in which antibiotics would be administered to cancer patients treated with ICIs to demonstrate their deleterious impact versus control, prospective observational studies and interventional trials involving microbiome modifiers are crucially needed to uncover the role of microbiome and improve patient outcomes. Such studies will reduce the existing publication bias by allowing analyses on more homogeneous populations, especially in terms of treatments received, which is not possible at this stage given the current state of the field. In the meantime, antibiotic prescription should be cautiously considered in cancer patients receiving ICIs.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42019145675.

Clinical factors influencing long-term survival in a real-life cohort of early stage non-small-cell lung cancer patients in Spain

Background

Current prognosis in oncology is reduced to the tumour stage and performance status, leaving out many other factors that may impact the patient´s management. Prognostic stratification of early stage non-small-cell lung cancer (NSCLC) patients with poor prognosis after surgery is of considerable clinical relevance. The objective of this study was to identify clinical factors associated with long-term overall survival in a real-life cohort of patients with stage I-II NSCLC and develop a prognostic model that identifies features associated with poor prognosis and stratifies patients by risk.

Methods

This is a cohort study including 505 patients, diagnosed with stage I-II NSCLC, who underwent curative surgical procedures at a tertiary hospital in Madrid, Spain.

Results

Median OS (in months) was 63.7 (95% CI, 58.7-68.7) for the whole cohort, 62.4 in patients submitted to surgery and 65 in patients submitted to surgery and adjuvant treatment. The univariate analysis estimated that a female diagnosed with NSCLC has a 0.967 (95% CI 0.936 - 0.999) probability of survival one year after diagnosis and a 0.784 (95% CI 0.712 - 0.863) five years after diagnosis. For males, these probabilities drop to 0.904 (95% CI 0.875 - 0.934) and 0.613 (95% CI 0.566 - 0.665), respectively. Multivariable analysis shows that sex, age at diagnosis, type of treatment, ECOG-PS, and stage are statistically significant variables (p<0.10). According to the Cox regression model, age over 50, ECOG-PS 1 or 2, and stage ll are risk factors for survival (HR>1) while adjuvant chemotherapy is a good prognostic variable (HR<1). The prognostic model identified a high-risk profile defined by males over 71 years old, former smokers, treated with surgery, ECOG-PS 2.

Conclusions

The results of the present study found that, overall, adjuvant chemotherapy was associated with the best long-term OS in patients with resected NSCLC. Age, stage and ECOG-PS were also significant factors to take into account when making decisions regarding adjuvant therapy.

The gut microbiome, immune check point inhibition and immune-related adverse events in non-small cell lung cancer

Systemic treatment options for patients with lung cancer have expanded in recent years, with a number of immunotherapeutic strategies now in our treatment armamentarium. Toxicity of and resistance to treatment hold a major stake in lung cancer morbidity and mortality. Herein, we summarise the background, current evidence and potential mechanisms underlying the role of the commensal gut microbiota in immunotherapy outcomes such as response and toxicity in patients with non-small cell lung cancer (NSCLC).

Analysis of interactions of immune checkpoint inhibitors with antibiotics in cancer therapy

The discovery of immune checkpoint inhibitors, such as PD-1/PD-L1 and CTLA-4, has played an important role in the development of cancer immunotherapy. However, immune-related adverse events often occur because of the enhanced immune response enabled by these agents. Antibiotics are widely applied in clinical treatment, and they are inevitably used in combination with immune checkpoint inhibitors. Clinical practice has revealed that antibiotics can weaken the therapeutic response to immune checkpoint inhibitors. Studies have shown that the gut microbiota is essential for the interaction between immune checkpoint inhibitors and antibiotics, although the exact mechanisms remain unclear. This review focuses on the interactions between immune checkpoint inhibitors and antibiotics, with an in-depth discussion about the mechanisms and therapeutic potential of modulating gut microbiota, as well as other new combination strategies.

The impact of antibiotic selection and interval time among advanced non-small cell lung cancer patients receiving prior antibacterial treatment and first-line chemotherapy

BACKGROUND

To determine whether antibiotic use before chemotherapy is associated with chemotherapy responses and patient outcomes among NSCLC patients and define the optimal interval between chemotherapy initiation and antibiotic treatment.

MATERIALS AND METHODS

One thousand four hundred and four advanced NSCLC patients receiving first-line platinum-based doublets therapy were retrospectively analyzed. Kaplan-Meier curve evaluated the impact of antibiotic use and type of antibiotics on the survival of patients. The factors affect the patient's prognosis were further confirmed by Cox regression. The optimal interval between antibiotic treatment and the initiation of chemotherapy was determined by the X-tile program.

RESULTS

NSCLC patients of 33.5% advanced underwent broad-spectrum antibiotic treatment prior to chemotherapy. In the chemotherapy only (Chemo) and chemotherapy plus antiangiogenesis (Chemo-angio) treatment groups, prior antibiotic treatment was associated with worse OS (Chemo: 13.8 vs. 17.6 months, p < 0.001; Chemo-angio:11.9 vs. 18.1 months, p = 0.012) and PFS (Chemo: 3.7 vs. 5.8 months, p < 0.001; Chemo-angio: 3.1 vs. 5.9 months, p < 0.001). Cox regression analysis revealed prior antibiotic administration as an independent predictor of OS and PFS (HR for PFS/OS: 1.925/1.452, both p < 0.001). Antibiotic usage duration (HR for PFS/OS: 1.030/1.036, p = 0.009/0.001) and type (PFS/OS: p < 0.001/p = 0.01) also showed significant association with patient prognosis, with calculated interval time cutoff values of 2, 4, and 2 days for fluoroquinolones, β-lactamase inhibitors, and cephalosporins, respectively.

CONCLUSION

Antibiotic use before first-line chemotherapy was associated with poor results in advanced NSCLC patients; treatment length and type being strongly correlated with patient outcomes. Appropriate prolongation of the time between two treatments may enhance patient survival. Further prospective research is however necessary.

Piperacillin/Tazobactam and Meropenem Use Increases the Risks for Acute Graft Rejection Following First Kidney Transplantation

Many broad-spectrum antibiotics (BSA) alter the intestinal microbiome that regulates adaptive immune responses. We hypothesized that BSA use before and early after kidney transplant may affect acute graft rejection (AGR). We carried out a retrospective cohort study on all patients who underwent kidney transplants in our institution. Patient demographics, clinical data, diagnosis, and treatment history were collected. Antibiotic use within 2 months prior to transplant and during the hospital admissions for transplant, as well as antibiotic types were recorded. A total of 357 consecutive first transplants were included for analysis. Median age was 52 years (range 7–76). A total of 67 patients received living donor and 290 deceased donor kidneys. A total of 19 patients received BSA within two months prior to transplant and 55 patients during the hospital admission for the transplant. With a median follow-up of 1270 days, 38 episodes of biopsy-proven AGR were recorded. There was no difference in the AGR rates during the first year between patients who received BSA and those who did not. However, the use of piperacillin/tazobactam or meropenem (PM) was associated with increased risks for the development of AGR, irrespective of the source of the donor grafts. Time to development of AGR was also shorter. Our data, therefore, suggest that the use of PM BSA prior to and immediately after kidney transplant increases the risks for AGR.

Risk Factors for Infections, Antibiotic Therapy, and Its Impact on Cancer Therapy Outcomes for Patients with Solid Tumors

Infections represent a significant cause of morbidity and mortality in cancer patients. Multiple factors related to the patient, tumor, and cancer therapy can affect the risk of infection in patients with solid tumors. A thorough understanding of such factors can aid in the identification of patients with substantial risk of infection, allowing medical practitioners to tailor therapy and apply prophylactic measures to avoid serious complications. The use of novel treatment modalities, including targeted therapy and immunotherapy, brings diagnostic and therapeutic challenges into the management of infections in cancer patients. A growing body of evidence suggests that antibiotic therapy can modulate both toxicity and antitumor response induced by chemotherapy, radiotherapy, and especially immunotherapy. This article provides a comprehensive review of potential risk factors for infections and therapeutic approaches for the most prevalent infections in patients with solid tumors, and discusses the potential effect of antibiotic therapy on toxicity and efficacy of cancer therapy.

Antibiotic Therapy is Associated with Worse Outcome in Patients with Hepatocellular Carcinoma Treated with Sorafenib

Background

Antibiotic treatment (ABT) affects the outcome of cancer patients treated with immune checkpoint inhibitors (ICIs) and chemotherapy, possibly by altering the gut microbiome. We investigated the impact of ABT on overall survival (OS) and progression-free survival (PFS) in patients with advanced HCC treated with sorafenib.

Methods

HCC patients treated with sorafenib between 05/2006 and 03/2020 at the Medical University of Vienna were retrospectively analyzed. ABT was defined as antibiotic use within 30 days prior to or after sorafenib initiation.

Results

Of 206 patients, the majority was male (n=171, 83%) with a mean age of 66±9.6 years. Half of patients (n=94, 46%) had impaired liver function (Child-Pugh stage B). Median time of follow-up was 10.8 (95% CI: 9.2-12.3) months. ABT was administered in 23 (11%) patients due to different types of proven or clinically suspected bacterial infections (n=17, 74%) and hepatic encephalopathy (n=6, 26%). The median duration of ABT was 14 (IQR: 12-30) days. Penicillin (n=13, 57%), followed by rifaximin (n=6, 26%), fluoroquinolones (n=3, 13%), and cephalosporins (n=1, 4%), was administered in the ABT group. The ABT group had a significantly shorter median OS (4.7 (95% CI: 3.2-6.1) months vs 11.4 (95% CI: 9.9-12.9) months, p=0.012), which was confirmed in multivariable analysis (HR: 1.91 (95% CI: 1.1-3.2), p=0.014). Similarly, PFS trended to be shorter in the ABT group (3.5 (95% CI: 1.6-5.4) months vs 4.8 (95% CI: 3.9-5.7) months, p=0.099). None of the 10 patients with complete or partial response was found in the ABT group.

Conclusion

ABT was independently associated with worse outcomes in sorafenib-treated HCC patients. Prospective studies are needed to elucidate the underlying mechanism.

How Could Antibiotics, Probiotics, and Corticoids Modify Microbiota and Its Influence in Cancer Immune Checkpoint Inhibitors: A Review

Immunotherapy has become a new paradigm in oncology, improving outcomes for several types of cancer. However, there are some aspects about its management that remain uncertain. One of the key points that needs better understanding is the interaction between immunotherapy and gut microbiome and how modulation of the microbiome might modify the efficacy of immunotherapy. Consequently, the negative impact of systemic antibiotics and corticosteroids on the efficacy of immunotherapy needs to be clarified.

How to Choose a Survival Period? The Impact of Antibiotic Use on OS or PFS in NSCLC Patients Treated With Immune Checkpoint Inhibitors: A Systematic Review and Meta-Analysis

Background:

The development of immunotherapy has dramatically changed the treatment of non-small-cell lung cancer. The negative association of antibiotics on the clinical activity of immune checkpoint inhibitors in patients with NSCLC is well known.

Methods:

PubMed, Embase, and Medline databases were searched until January 11, 2020. We included retrospective studies of ICIs (e.g., PD-1, PD-L1, and CTLA-4). The clinical outcomes were progression-free survival (PFS) and overall survival (OS). Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated, and subgroup and sensitivity analyses were performed.

Results:

Our results indicated that the use of antibiotics reduced the survival of NSCLC patients treated with ICIs. The pooled HRs of PFS and OS were HR = 1.41 (95% CI = 1.23-1.61; P < 0.001) and HR = 2.16 (95% CI = 1.79-2.60; P < 0.001). We divided the studies into 5 subgroups according to antibiotic exposure time. Subgroup analysis showed that the patients that were administered antibiotics [−60 days; 0 days] or [−30 days; 0 days] before the initiation of ICIs treatment had a poorer OS rate, whereas those patients that were administered antibiotics [0 days; 30 days] after the initiation of ICIs treatment had a poorer PFS rate. In summary, ATB treatment in patients [−60 days; +30 days] near the initiation of ICIs treatment significantly reduced the survival in NSCLC patients.

Conclusion:

Our results indicated that ATB use is negatively associated with survival in NSCLC patients treated with ICIs immunotherapy. Similar studies involving a larger sample of cases are still being published. This meta-analysis identified that the timing of ATB treatment in NSCLC patients receiving ICIs immunotherapy has different effects on the OS and PFS of these patients. ATB treatment prior to the initiation of ICIs treatment affects OS, whereas ATB treatment after the initiation of ICIs treatment affects PFS.

Gut microbiota-mediated immunomodulation in tumor

Tumor immunity consists of various types of cells, which serve an important role in antitumor therapy. The gastrointestinal tract is colonized by trillions of microorganisms, which form the gut microbiota. In addition to pathogen defense and maintaining the intestinal ecosystem, gut microbiota also plays a pivotal role in various physiological processes. Recently, the association between these symbionts and cancer, ranging from oncogenesis and cancer progression to resistance or sensitivity to antitumor therapies, has attracted much attention. Metagenome analysis revealed a significant difference between the gut microbial composition of cancer patients and healthy individuals. Moreover, modulation of microbiome could improve therapeutic response to immune checkpoint inhibitors (ICIs). These findings suggest that microbiome is involved in cancer pathogenesis and progression through regulation of tumor immunosurveillance, although the exact mechanisms remain largely unknown. This review focuses on the interaction between the microbiome and tumor immunity, with in-depth discussion regarding the therapeutic potential of modulating gut microbiota in ICIs. Further investigations are warranted before gut microbiota can be introduced into clinical practice.

Antimicrobial therapy during cancer treatment: Beyond antibacterial effects

Cancer treatment options have evolved to include immunotherapy and targeted therapy, in addition to traditional chemoradiation. Chemoradiation places the patient at a higher risk of infection through a myelosuppressive effect. High clinical suspicion and early use of antimicrobials play a major role in decreasing any associated morbidity and mortality. This has led to a widespread use of antimicrobials in cancer patients. Antimicrobial use, however, does not come without its perils. Dysbiosis caused by antimicrobial use affects responses to chemotherapeutic agents and is prognostic in the development and severity of certain cancer treatment-related complications such as graft-versus-host disease and Clostridioides difficile infections. Studies have also demonstrated that an intact gut microbiota is essential in the anticancer immune response. Antimicrobial use can therefore modulate responses and outcomes with immunotherapy targeting immune checkpoints. In this review, we highlight the perils associated with antimicrobial use during cancer therapy and the importance of a more judicious approach. We discuss the nature of the pathologic changes in the gut microbiota resulting from antimicrobial use. We explore the effect these changes have on responses and outcomes to different cancer treatment modalities including chemotherapy and immunotherapy, as well as potential adverse clinical consequences in the setting of stem cell transplant.

Antibiotics and steroids, the double enemies of anticancer immunotherapy: a review of the literature

The advent of immunotherapy in onco-haematology has represented a kind of revolution that has been able to modify the prognosis of numerous tumours that until recently would have been rapidly lethal. While much is known about the mechanism of action of these drugs, relatively little is known about the factors that represent potential predictors of response and toxicity. Among these factors, the simultaneous administration of antibiotics and/or steroids seems to have a negative impact. Furthermore, several retrospective studies have highlighted the strong link between cancer and gut microbiota, regardless of the tumour site, and how microbiota, playing a key role in the prevention of systemic inflammation at various levels and in the intestinal homeostasis, can be negatively influenced by the dysbiosis caused by antibiotic therapy administered during or in the weeks immediately preceding the start of immunotherapy. Moreover, we assume that the concurrent administration of steroids, which is often necessary in cancer patients, likely results in a deleterious effect on the therapeutic outcomes of immunotherapy. In this review, we will try to clarify the evidence on the possible detrimental effects of antibiotics and steroids, which are currently considered the double enemies of anticancer immunotherapy.

Microbes in lung cancer initiation, treatment, and outcome: Boon or bane?

Lung cancer is the top reason for cancer-related deaths worldwide. The 5-year overall survival rate of lung cancer is approximately 20 % due to the delayed diagnosis and low response rate to regular treatments. Microbiota, both host-microbiota and alien pathogenic microbiota, have been investigated to be involved in a complicated and contradictory relationship with lung cancer initiation, treatments, and prognosis. Disorders of certain host-microbiota and pathogen infection are associated with the risk of lung cancers based on epidemiological evidence, and antibiotics (ATBs) could dramatically impair anti-cancer treatment efficacy, including chemotherapy and immunotherapy. Moreover, probiotics and microbe-mediated drugs are potential approaches to enhance regular anti-tumor treatments. Therefore, the knowledge of the complex dual effect of microbes on lung cancer is beneficial to take their essence and remove their dross. This review offers insight into the current trends and advancements in microbiota or microbial components related to lung cancer.

Broad-Spectrum Antibiotic Regimen Affects Survival in Patients Receiving Nivolumab for Non-Small Cell Lung Cancer

Antibiotic-induced dysbiosis may affect the efficacy of immune checkpoint inhibitors. We investigated the impact of antibiotics on the clinical outcomes of nivolumab in patients with non-small cell lung cancer (NSCLC). Patients who received nivolumab for NSCLC between July 2015 and June 2018 and who were followed up until June 2020 were included in a retrospective cohort analysis. Of 140 eligible patients, 70 were on antibiotics. Overall survival (OS) was shorter in patients on antibiotics (ABX) compared to those not on antibiotics (NoABX) (p = 0.014). OS was negatively associated with piperacillin/tazobactam (PTZ) (HR = 3.31, 95% CI: 1.77–6.18), days of therapy (DOT) ≥ 2 weeks (HR = 2.56, 95% CI: 1.30–5.22) and DOT of PTZ. The defined daily dose (DDD) in PTZ (r = 0.27) and glycopeptides (r = 0.21) showed weak correlations with mortality. There was no difference in progression-free survival (PFS) between ABX and NoABX; however, PFS was negatively associated with the antibiotic class PTZ and DOT of PTZ. Therefore, the use of a broad-spectrum antibiotic, such as PTZ, the long-term use of antibiotics more than 2 weeks in total and the large amount of defined daily dose of specific antibiotics were associated with decreased survival in patients receiving nivolumab for NSCLC.

Recognizing Prognostic and Predictive Biomarkers in the Treatment of Non-Small Cell Lung Cancer (NSCLC) with Immune Checkpoint Inhibitors (ICIs)

Immunotherapy plays a central role in the treatment of NSCLC and biomarkers predicting response to ICIs are valuable therapeutic tools. Programmed death-ligand 1 (PD-L1) immunohistochemistry (IHC) is integral in therapy selection as its positive predictive nature to ICIs in the metastatic setting is well documented. Tumor mutational burden (TMB) has undergone much study and, while results are somewhat mixed, there is evidence for its positive predictive value with ICI use. Additional markers such as tumor-infiltrating lymphocytes (TILs), gene expression profiling (GEP), mismatch repair (MMR) and microsatellite instability (MSI), somatic mutations, neutrophil to leukocyte ratio (NLR), smoking history, medication history, and immune-related adverse event (irAE) development can further guide clinicians.

Use of antibiotics is associated with worse clinical outcomes in patients with cancer treated with immune checkpoint inhibitors: A systematic review and meta-analysis

OBJECTIVES

Observational and experimental studies suggest that the use of antibiotics close to administration of immune checkpoint inhibitors (ICI) can have a negative effect on tumour response and patient survival, due to microbiome dysbiosis and the resultant suppression of host immune response against neoplastic cells.

METHODS

A systematic search of PUBMED and EMBASE was undertaken for studies published between 1 January 2017 and 1 June 2020, evaluating the association between the use of antibiotics and clinical outcomes in patients with cancer treated with ICIs. A meta-analysis of the association between the use of antibiotics and clinical outcomes was also performed.

RESULTS

Forty-eight studies met the inclusion criteria (12,794 patients). Use of antibiotics was associated with shorter overall survival [hazard ratio (HR) 1.88, 95% confidence interval (CI) 1.59-2.22; adjusted HR 1.87, 95% CI 1.55-2.25] and progression-free survival (HR 1.52, 95% CI 1.36-1.70; adjusted HR 1.93, 95% CI 1.59-2.36), decreased response rate [odds ratio (OR) 0.54, 95% CI 0.34-0.86] and more disease progression (OR 2.00, 95% CI 1.27-3.14). The negative association between the use of antibiotics and progression-free survival was stronger in patients with renal cell carcinoma or melanoma compared with lung cancer. Only antibiotic administration >1 month prior to ICI initiation was associated with increased disease progression. Heterogeneity was substantial for all outcomes.

CONCLUSIONS

Recent use of antibiotics in patients with cancer treated with ICIs was associated with worse clinical outcomes. Such patients may benefit from dedicated antimicrobial stewardship programmes.

Relating Gut Microbiome and Its Modulating Factors to Immunotherapy in Solid Tumors: A Systematic Review

Background: Gut microbiome is proved to affect the activity of immunotherapy in certain tumors. However, little is known if there is universal impact on both the treatment response and adverse effects (AEs) of immune checkpoint inhibitors (ICIs) across multiple solid tumors, and whether such impact can be modulated by common gut microbiome modifiers, such as antibiotics and diet.

Methods: A systematic search in PubMed followed by stringent manual review were performed to identify clinical cohort studies that evaluated the relevance of gut microbiome to ICIs (response and/or AEs, 12 studies), or association of antibiotics with ICIs (17 studies), or impact of diet on gut microbiome (16 studies). Only original studies published in English before April 1st, 2020 were used. Qualified studies identified in the reference were also included.

Results: At the phylum level, patients who had enriched abundance in Firmicutes and Verrucomicrobia almost universally had better response from ICIs, whereas those who were enriched in Proteobacteria universally presented with unfavorable outcome. Mixed correlations were observed for Bacteroidetes in relating to treatment response. Regarding the AEs, Firmicutes correlated to higher incidence whereas Bacteroidetes were clearly associated with less occurrence. Interestingly, across various solid tumors, majority of the studies suggested a negative association of antibiotic use with clinical response from ICIs, especially within 1-2 month prior to the initiation of ICIs. Finally, we observed a significant correlation of plant-based diet in relating to the enrichment of “ICI-favoring” gut microbiome (P = 0.0476).

Conclusions: Gut microbiome may serve as a novel modifiable biomarker for both the treatment response and AEs of ICIs across various solid tumors. Further study is needed to understand the underlying mechanism, minimize the negative impact of antibiotics on ICIs, and gain insight regarding the role of diet so that this important lifestyle factor can be harnessed to improve the therapeutic outcomes of cancer immunotherapy partly through its impact on gut microbiome.

Safety and efficacy of immune checkpoint inhibitors in non-small-cell lung cancer: focus on challenging populations

In recent years, immune-checkpoint inhibitors (ICIs) have represented one of the major breakthroughs in advanced non-small cell lung cancer treatment scenario. However, enrollment in registering clinical trials is usually restricted, since frail patients (i.e., elderly, individuals with poor performance status and/or active brain metastases), as well as patients with chronic infections or who take concurrent medications, such as steroids, are routinely excluded. Thus, safety and efficacy of ICIs for these subgroups have not been adequately assessed in clinical trials, although these populations often occur in clinical practice. We reviewed the available data regarding the use of ICIs in these 'special' populations, including a focus on the issues raised by the administration of immunotherapy in lung cancer patients infected with Sars-Cov-2.

Gastric Cancer Microbiome

Identifying a microbiome pattern in gastric cancer (GC) is hugely debatable due to the variation resulting from the diversity of the studied populations, clinical scenarios, and metagenomic approach. H. pylori remains the main microorganism impacting gastric carcinogenesis and seems necessary for the initial steps of the process. Nevertheless, an additional non-H. pylori microbiome pattern is also described, mainly at the final steps of the carcinogenesis. Unfortunately, most of the presented results are not reproducible, and there are no consensual candidates to share the H. pylori protagonists. Limitations to reach a consistent interpretation of metagenomic data include contamination along every step of the process, which might cause relevant misinterpretations. In addition, the functional consequences of an altered microbiome might be addressed. Aiming to minimize methodological bias and limitations due to small sample size and the lack of standardization of bioinformatics assessment and interpretation, we carried out a comprehensive analysis of the publicly available metagenomic data from various conditions relevant to gastric carcinogenesis. Mainly, instead of just analyzing the results of each available publication, a new approach was launched, allowing the comprehensive analysis of the total sample amount, aiming to produce a reliable interpretation due to using a significant number of samples, from different origins, in a standard protocol. Among the main results, Helicobacter and Prevotella figured in the "top 6" genera of every group. Helicobacter was the first one in chronic gastritis (CG), gastric cancer (GC), and adjacent (ADJ) groups, while Prevotella was the leader among healthy control (HC) samples. Groups of bacteria are differently abundant in each clinical situation, and bacterial metabolic pathways also diverge along the carcinogenesis cascade. This information may support future microbiome interventions aiming to face the carcinogenesis process and/or reduce GC risk.

Effects of Antibiotic Use on Outcomes in Cancer Patients Treated Using Immune Checkpoint Inhibitors: A Systematic Review and Meta-Analysis

Antibiotic (ATB) use seems to negatively affect the outcomes of immune checkpoint inhibitors (ICIs). The aim of this review is to clarify whether ATB use influences the efficacy of ICI treatment in cancer patients. Databases of MEDLINE, Embase, and Cochrane Library were searched for reports published in English between January 2007 and December 2019. We included studies that compared the outcomes of ATB use and no-ATB use in cancer patients using ICIs. Two reviewers independently selected eligible studies and extracted the data. Meta-analysis was performed with pooling of unadjusted hazard ratios (HRs) for overall survival (OS) and progression-free survival (PFS), and with pooling of odds ratios (ORs) for objective response rate (ORR). Thirty-eight studies involving 8409 patients were finally included for qualitative or quantitative analyses. Cancer types included renal cell carcinoma, non-small cell lung cancer, urothelial carcinoma, melanoma, gastrointestinal cancer, and others. Meta-analyses revealed that ATB use was associated with poor OS [HR: 1.80, 95% confidence interval (CI): 1.44-2.26, P<0.001], PFS (HR: 1.55, 95% CI: 1.26-1.91, P<0.001) and ORR (OR: 0.63, 95% CI: 0.42-0.95, P=0.03). Subgroup analysis found that these relationships were not influenced by cancer type or ICI regimens, but were dependent on the timing of ATB use. Narrative results of multivariable analyses further confirmed the negative effects of ATB use on OS and PFS. In cancer patients using ICIs, pre-ATB use close to the start of ICI treatment (within 60 d) was detrimental to outcomes in terms of OS, PFS, and ORR.

Immunotherapy in advanced Non-Small Cell Lung Cancer patients with poor performance status: The role of clinical-pathological variables and inflammatory biomarkers

BACKGROUND

The introduction of immunotherapy has improved the prognosis of patients with Non-Small Cell Lung Cancer (NSCLC). However, data in poor ECOG Performance Status (PS) patients remain scant due to their exclusion from randomized trials.

MATERIAL AND METHODS

We analyzed data of patients with advanced NSCLC treated with immunotherapy in two Italian Centers, to evaluate the impact of PS (0-1 vs 2) on disease control rate (DCR), progression free survival (PFS) and overall survival (OS). Chi-square test was used to compare clinical-pathological variables, their impact on survival was evaluated through Cox proportional hazard models.

RESULTS

Among 404 patients included, PS was 0 in 137 (33.9 %), 1 in 208 (51.5 %) and 2 in 59 (14.6 %) patients; 143 were female and 90 had squamous NSCLC. Clinical-pathological variables were uniformly distributed except for higher prevalence of liver metastases in patients with poor PS. We found that PS2 patients showed worse outcomes in terms of DCR (21.8 % vs 50.3 %, p = 0.001), PFS [2.0 (95 % CI 1.6-3.0) vs 3.0 (95 % CI 2.7-4.0) months, p < 0.0001] and OS [4.0 (95 % CI 2.8-5.7) vs 13.2 (95 % CI 11.0-15.8) months, p < 0.0001]. PS2 status, negative PDL1 expression and early corticosteroids exposure as well as higher Neutrophil to Lymphocyte Ratio and LDH at baseline were associated with worse outcomes at univariate and multivariable analysis. Subgroup analysis confirmed poor outcomes in PS2 patients with high LDH and concomitant corticosteroid therapies. The incidence of Grade 3/4 adverse events was 11.3 % in PS 0-1 and 10.2 % in PS 2 patients (p = 0.81).

CONCLUSION

Our data confirm reduced efficacy of immunotherapy in patients with poor PS even though a good safety. Despite PS remains the most powerful independent prognostic factor for NSCLC, LDH levels and steroids exposure could support the decision making in PS2 patients.

Infections and Immunotherapy in Lung Cancer: A Bad Relationship?

Infectious diseases represent a relevant issue in lung cancer patients. Bacterial and viral infections might influence the patients’ prognosis, both directly affecting the immune system and indirectly impairing the outcome of anticancer treatments, mainly immunotherapy. In this analysis, we aimed to review the current evidence in order to clarify the complex correlation between infections and lung cancer. In detail, we mainly explored the potential impact on immunotherapy outcome/safety of (1) bacterial infections, with a detailed focus on antibiotics; and (2) viral infections, discriminating among (a) human immune-deficiency virus (HIV), (b) hepatitis B/C virus (HBV-HCV), and (c) Sars-Cov-2. A series of studies suggested the prognostic impact of antibiotic therapy administration, timing, and exposure ratio in patients treated with immune checkpoint inhibitors, probably through an antibiotic-related microbiota dysbiosis. Although cancer patients with HIV, HBV, and HCV were usually excluded from clinical trials evaluating immunotherapy, some retrospective and prospective trials performed in these patient subgroups reported similar results compared to those described in not-infected patients, with a favorable safety profile. Moreover, patients with thoracic cancers are particularly at risk of COVID-19 severe outcomes and mortality. Few reports speculated about the prognostic implications of anticancer therapy, including immunotherapy, in lung cancer patients with concomitant Sars-Cov-2 infection, showing, to date, inconsistent results. The correlation between infectious diseases and immunotherapy remains to be further explored and clarified in the context of dedicated trials. In clinical practice, the accurate and prompt multidisciplinary management of lung cancer patients with infections should be encouraged in order to select the best treatment options for these patients, avoiding unexpected toxicities, while maintaining the anticancer effect.

Is the survival of patients treated with ipilimumab affected by antibiotics? An analysis of 1585 patients from the French National hospital discharge summary database (PMSI)

Background: The gut microbiota has a key role in the regulation of the immune system. Disruption of the gut microbiota’s composition by antibiotics might significantly affect the efficacy of immune checkpoint inhibitors. In a study of patients treated with ipilimumab, we sought to assess the relationship between overall survival and in-hospital antibiotic administration.

Methods: Patients having been treated with ipilimumab between January 2012 and November 2014 were selected from the French National Hospital Discharge Summary Database. Exposure to antibiotics was defined as the presence of a hospital stay with a documented systemic bacterial infection in the 2 months before or the month after initiation of the patient’s first ever course of ipilimumab. The primary outcome was overall survival.

Results: We studied 43,124 hospital stays involving 1585 patients from 97 centers. All patients had received ipilimumab monotherapy for advanced melanoma. Overall, 117 of the 1585 patients (7.4%) were documented as having received systemic antibiotic therapy in hospital during the defined exposure period. The median overall survival time was shorter in patients with infection (6.3 months, vs. 15.4 months in patients without an infection; hazard ratio (HR) = 1.88, 95% confidence interval [1.46; 2.43], p = 10⁻⁶). In a multivariate analysis adjusted for covariates, infection was still significantly associated with overall survival (HR = 1.68, [1.30; 2.18], p = 10⁻⁵).

Conclusions: In patients treated with ipilimumab for advanced melanoma, infection, and antibiotic administration in hospital at around the time of the patient’s first ever course of ipilimumab appears to be associated with significantly lower clinical benefit.

Antibiotics, cancer risk and oncologic treatment efficacy: a practical review of the literature

Antibiotics have been extensively used to treat infectious diseases over the past century and have largely contributed to increased life expectancy over time. However, antibiotic use can impose profound and protracted changes to the diversity of the microbial ecosystem, affecting the composition of up to 30% of the bacterial species in the gut microbiome. By modifying human microbiota composition, antibiotics alter the action of several oncologic drugs, potentially leading to decreased efficacy and increased toxicities. Whether antibiotics interfere with cancer therapies or even increase the risk of cancer development has been under investigation, and no randomised trials have been conducted so far. The aim of the current review is to describe the possible effects of antibiotic therapies on different oncologic treatments, especially immunotherapies, and to explore the link between previous antibiotics use and the development of cancer.

A Significant Question in Cancer Risk and Therapy: Are Antibiotics Positive or Negative Effectors? Current Answers and Possible Alternatives

Cancer is predominantly considered as an environmental disease caused by genetic or epigenetic alterations induced by exposure to extrinsic (e.g., carcinogens, pollutants, radiation) or intrinsic (e.g., metabolic, immune or genetic deficiencies). Over-exposure to antibiotics, which is favored by unregulated access as well as inappropriate prescriptions by physicians, is known to have led to serious health problems such as the rise of antibiotic resistance, in particular in poorly developed countries. In this review, the attention is focused on evaluating the effects of antibiotic exposure on cancer risk and on the outcome of cancer therapeutic protocols, either directly acting as extrinsic promoters, or indirectly, through interactions with the human gut microbiota. The preponderant evidence derived from information reported over the last 10 years confirms that antibiotic exposure tends to increase cancer risk and, unfortunately, that it reduces the efficacy of various forms of cancer therapy (e.g., chemo-, radio-, and immunotherapy alone or in combination). Alternatives to the current patterns of antibiotic use, such as introducing new antibiotics, bacteriophages or enzybiotics, and implementing dysbiosis-reducing microbiota modulatory strategies in oncology, are discussed. The information is in the end considered from the perspective of the most recent findings on the tumor-specific and intracellular location of the tumor microbiota, and of the most recent theories proposed to explain cancer etiology on the notion of regression of the eukaryotic cells and systems to stages characterized for a lack of coordination among their components of prokaryotic origin, which is promoted by injuries caused by environmental insults.

Antibiotic administration shortly before or after immunotherapy initiation is correlated with poor prognosis in solid cancer patients: An up-to-date systematic review and meta-analysis

OBJECTIVE

Immune checkpoint inhibitors (ICIs) have recently achieved inspiring performance in improving the prognosis of various solid tumors. Gut microbiome plays a crucial modulatory role in the efficacy of ICIs, which can be influenced by antibiotic (ATB) administration. In this meta-analysis, we aimed to clarify the correlations of ATB administration with the prognosis of solid cancer patients receiving ICI treatment.

METHOD

The eligible literatures were searched using PubMed, Cochrane Library, Web of Science, and Clinical trials.gov databases before 29 February 2020. The correlations of ATB administration with overall survival (OS) and progression-free survival (PFS) were determined using Hazard ratios (HRs) coupled with 95% confidence intervals (CIs).

RESULTS

A total of 33 studies enrolling 5565 solid cancer patients receiving ICI treatment were included in this meta-analysis. As a whole, ATB administration was significantly correlated worse OS (HR = 1.76, 95%CI = 1.41-2.19, P < 0.00001) and PFS (HR = 1.76, 95%CI = 1.47-2.12, P < 0.00001). This significant association was then observed in the subgroup analysis based on region (except for OS in Europe), sample size, age, therapeutic strategy and ICI type. The similar results were also found in subgroup analysis for lung, renal cell (except for OS) and other cancers (such as melanoma) but not for mixed cancers. In addition, the ICI efficacy was more likely to be diminished by ATB administration within a time frame from 60 days before to 60 days after ICI initiation.

CONCLUSION

ATBs should be used cautiously in solid cancer patients receiving ICIs. However, further validations are still essential due to existing publication bias.

Survival of Patients Treated with Antibiotics and Immunotherapy for Cancer: A Systematic Review and Meta-Analysis

Antibiotics (ABs) are common medications used for treating infections. In cancer patients treated with immune checkpoint inhibitors (ICIs), concomitant exposure to ABs may impair the efficacy of ICIs and lead to a poorer outcome compared to AB non-users. We report here the results of a meta-analysis evaluating the effects of ABs on the outcome of patients with solid tumours treated with ICIs. PubMed, the Cochrane Library and Embase were searched from inception until September 2019 for observational or prospective studies reporting the prognoses of adult patients with cancer treated with ICIs and with or without ABs. Overall survival (OS) was the primary endpoint, and progression-free survival (PFS) was the secondary endpoint. The effect size was reported as hazard ratios (HRs) with a 95% confidence interval (CI) and an HR > 1 associated with a worse outcome in ABs users compared to AB non-users. Fifteen publications were retrieved for a total of 2363 patients. In the main analysis (n = 15 studies reporting data), OS was reduced in patients exposed to ABs before or during treatment with ICIs (HR = 2.07, 95%CI 1.51–2.84; p < 0.01). Similarly, PFS was inferior in AB users in n = 13 studies with data available (HR = 1.53, 95%CI 1.22–1.93; p < 0.01). In cancer patients treated with ICIs, AB use significantly reduced OS and PFS. Short duration/course of ABs may be considered in clinical situations in which they are strictly needed.

Concomitant use of antibiotics and immune checkpoint inhibitors in patients with solid neoplasms: retrospective data from real-world settings

Background

The use of antibiotics is known to alter the gut microbiome and it is hypothesised that the use of antibiotics may also alter the response to immune checkpoint inhibitors (ICI). As data is limited from real-world settings, we performed a retrospective audit of patients who received ICI along with concomitant antibiotics.

Patients and Methods

This study is a retrospective audit of a prospectively collected the database of patients who received ICI for advanced solid tumours in any line between August 2015 and November 2018 at Tata Memorial Hospital, Mumbai, India. Antibiotic use was recorded from 2 weeks before the start of ICI and concomitantly with ICI. All statistical calculations were performed using Statistical Package for the Social Sciences (SPSS) statistical software for windows version 20.0.

Results

A total of 155 patients were identified as having received ICI during the study period, out of which 70 (44%) patients received antibiotics. Median PFS in patients who received antibiotics was 1.7 months (95% CI: 1.1–2.3) as against 3.6 months (95% CI: 2.3–4.8) for patients who did not receive antibiotics (p = 0.912). Median OS in the patients who received antibiotics was 3.9 months (95% CI: 1.8–11.4) as compared to 9.2 months (95% CI: 4.2–12.3) who did not receive antibiotics p = 0.053 (HR = 1.023; 95% CI: 1.00–1.04). Among the patients who received antibiotics, median OS for patients who received ≤10 days of antibiotics was 8.8 months (95% CI: 4.2–11.2) while for patients receiving >10 days of antibiotics, it was 2.8 months (95% CI: 1.2–4.4), p = 0.025 (HR = 2.0, 95% CI: 1.1–3.7). Thirty-three (21.2% of total) patients received antibiotics during the window of 2 weeks before the start of ICI to 2 months of starting ICI. Median OS in the patients who received antibiotics in this window was 2.8 months (95% CI: 1.2–4.5) as compared to 9.2 months (95% CI: 5.2–13.1) who did not receive antibiotics p = 0.008 (HR = 1.8; 95%CI: 1.2–3.0).

Conclusions

This study shows that the judicious use of antibiotics is required in patients on ICI or scheduled to be started on ICI.

NSCLC Immunotherapy Efficacy and Antibiotic Use: A Systematic Review and Meta-Analysis

Immune checkpoint inhibitors (ICIs) have dramatically improved patient outcomes in a variety of tumor types, but with variable efficacy. Recent research has suggested that antibiotic-induced disruption of the microbiota may impact ICI efficacy. We performed a systematic review and meta-analysis of studies that assessed the impact of antibiotic use on the survival of patients diagnosed with NSCLC and treated with ICI. We systematically searched Medline, the Cochrane Library, and major oncology conferences proceedings. Eligible studies mentioned hazard ratio or Kaplan-Meier curves for progression-free survival (PFS) or overall survival (OS) based on antibiotic exposure before or during ICI treatment. We identified 23 eligible studies. The impact of antibiotics was then evaluated in 2208 patients for PFS and 5560 for OS. For both PFS and OS meta-analyses, the between-study heterogeneity was high (Higgins and Thompson I² of 69% and 80%, respectively). The pooled hazard ratio was 1.47 (95% confidence interval [CI]: 1.13-1.90) for PFS and 1.69 (95% CI: 1.25-2.29) for OS revealing a significantly reduced survival in patients with NSCLC exposed to antibiotics. The median OS was reduced on average by 6.7 months (95% CI: 5.1-8.4) in the patients exposed to antibiotics. The effect seems to depend on the time window of exposure with stronger effects reported when the patients took antibiotics [-60 days; +60 days] around ICI initiation. In patients with NSCLC, the findings of the meta-analysis indicate that antibiotic use before or during treatment with ICI leads to a median OS decreased by more than 6 months. Specifically, exposure shortly before or after ICI initiation seems to be particularly detrimental, whereas antibiotic use later during disease course does not seem to alter survival. Because PFS and OS were difficult to compare between studies owing to heterogeneity and the multiple confounding factors identified, further studies are needed to strengthen the understanding of this phenomenon.

The association between antibiotics use and outcome of cancer patients treated with immune checkpoint inhibitors: A systematic review and meta-analysis

OBJECTIVE

This meta-analysis was to evaluate the impact of antibiotics use on survival of cancer patients with immune checkpoint inhibitors (ICIs).

METHODS

Electronic databases including Pubmed, Emabse, and the Cochrane library were searched. The primary endpoints were overall survival (OS) and progression-free survival (PFS).

RESULTS

A total of 20 retrospective studies were included. The median OS (7.9 months versus 17.65 months) and PFS (2.4 months versus 4.4 months) of the antibiotics use group were shorter compared to control group. Meta-analysis also showed that the risks of death (HR = 1.90, 95 % CI: 1.55-2.34; P < 0.01) and disease progression (HR=1.53, 95 % CI: 1.30-1.79; P < 0.01) in antibiotics positive group were significantly higher than that of the negative group. The prognostic role of antibiotics use was still significant regardless of cancer types and timing of antibiotics (P < 0.01 for all).

CONCLUSION

Use of antibiotics may be associated with worse outcomes in cancer patients treated with ICIs.

Antibiotic therapy and outcome from immune-checkpoint inhibitors

Sensitivity to immune checkpoint inhibitor (ICPI) therapy is governed by a complex interplay of tumor and host-related determinants. Epidemiological studies have highlighted that exposure to antibiotic therapy influences the probability of response to ICPI and predict for shorter patient survival across malignancies. Whilst a number of studies have reproducibly documented the detrimental effect of broad-spectrum antibiotics, the immune-biologic mechanisms underlying the association with outcome are poorly understood. Perturbation of the gut microbiota, an increasingly well-characterized factor capable of influencing ICPI-mediated immune reconstitution, has been indicated as a putative mechanism to explain the adverse effects attributed to antibiotic exposure in the context of ICPI therapy. Prospective studies are required to validate antibiotic-mediated gut perturbations as a mechanism of ICPI refractoriness and guide the development of strategies to overcome this barrier to an effective delivery of anti-cancer immunotherapy.

Immunotherapy in head and neck cancer: The great challenge of patient selection

The development of immune checkpoint inhibitors (ICIs) revolutionized the therapeutic landscape in head and neck cancer. However, the majority of patients present primary resistance to ICIs and do not benefit from use of these agents, highlighting the need of developing predictive biomarkers to better determine who will benefit from treatment with ICIs. Patient's related clinical characteristics, disease related features, pathological and molecular factors, as well as emerging immune predictive biomarkers can be considered for the selection of those patients who would be the best candidate for immunotherapy. We examined these factors, emerging from the results of currently available studies in head and neck squamous cell carcinoma (HNSCC), in order to provide a useful tool which could assist the oncologist in their clinical practice.

Characterization of patients with metastatic non-small-cell lung cancer obtaining long-term benefit from immunotherapy

Aim: A minority of patients gains advantage from immunotherapy (IO). Predictive variables of long-term benefit (LTB) are incompletely understood. Materials & methods: We retrospectively collected data about metastatic non-small-cell lung cancer patients treated with IO from April 2013 to July 2017. We defined LTB to IO as complete response (CR), partial response (PR) or disease stability as best response and maintaining it for ≥12 months. Results: Thirty-five of the 147 patients had LTB. More LTB patients than controls showed CR/PR as first and best response to IO. Only CR/PR as best response to IO retained association to LTB at multivariate analyses. Conclusion: Objective response appears as a central factor for LTB from IO.

Concomitant medications during immune checkpoint blockage in cancer patients: Novel insights in this emerging clinical scenario

The use of immune checkpoint inhibitors (ICIs) in cancer patients is rapidly growing. However, the potential impact of some widely used concomitant medications is still largely unclear. Emerging data suggest that gut microbiota may affect the efficacy of ICIs, leading to the hypothesis that concurrent antibiotics and proton pump inhibitors use could have a detrimental effect. In addition, steroid use might potentially impair the activity of immunotherapy, due its known immunosuppressive effects, and some safety concerns have been raised in patients receiving commonly used vaccination during ICIs. However, all randomized trials evaluating ICIs consistently excluded patients receiving high corticosteroid doses and data regarding other concomitant medications are lacking. Recently, several retrospective studies have tried to address this unmet medical need. Herein we discuss the latest evidence on the influence of these medications, critically analyzing the data reported so far and the possible implications in our clinical practice.