Effect of young age (below 40 years) on oncologic outcomes in Lebanese patients with breast cancer: a matched cohort study.

BACKGROUND: Developing countries have a significantly higher incidence of breast cancer in patients younger than 40 years as compared to developed countries. This study aimed to examine if young age at diagnosis is an independent prognostic factor for worse survival outcomes in breast cancer as well as the effect of age on Disease-free survival (DFS) and local recurrence free survival (LRFS) after adjusting for various tumor characteristics, local and systemic treatments. METHODS: This is a secondary analysis of prospective cohort of patients from two existing databases. We identified patients with breast cancer aged 40 years or less and we matched them to those older than 40 years. We also matched based on stage and molecular subtypes. In cohort 1, we matched at a ratio of 1:1, while in cohort 2 we matched at a ratio of 1:3. RESULTS: In cohort 1, Disease-free survival (DFS) at 5 years was significantly shorter for those younger than 40 years (75.6% and 92.7% respectively; p < 0.03). On multivariate analysis, only chemotherapy was found to be significant, while age was not found to be an independent predictor of prognosis. Local recurrence free survival at 5 years was similar between both age categories. Only hormonal therapy is a significant predictor for LRFS at 5 years. In the second cohort, DFS and LRFS at 3 years were similar between those younger and those older than 40 years. On multivariate analysis, no factor including age was found to be an independent predictor of prognosis. CONCLUSION: Data in the literature is controversial on the effect of young age on breast cancer prognosis. Our findings could not demonstrate that age is an independent prognostic factor in our population. There is a need for outcomes from larger, prospective series that have longer follow-ups and more data from our region.

Esophageal cancer: a twenty-four-year experience at a tertiary care center with an evaluation of the prognostic significance of the neutrophil-lymphocyte ratio.

BACKGROUND: A high neutrophil-lymphocyte ratio (NLR) may be associated with worse survival in esophageal cancer (EC). Our aims were to describe the demographic and clinical data of EC in a tertiary referral center in Lebanon and to determine the prognostic value of NLR. METHODS: A retrospective cohort study based on chart review of patients diagnosed with EC was conducted at the American University of Beirut Medical Center (AUBMC). The demographic characteristics, clinical presentation and outcomes were described and compared between squamous cell carcinomas (ESCC) and adenocarcinomas (EAC). Data about esophageal cancer incidence were obtained from the National Cancer Registry, the Ministry of Public Health and GLOBOCAN 2020. Cox regression analysis was performed to determine whether the NLR is an independent predictor of survival, using variables based on clinical knowledge and previously established data. RESULTS: 110 patients were diagnosed with EC, which was the least common among other gastrointestinal malignancies. Our follow up rates reached 86.4%. The median survival was 9 months (IQR 3-25.5.) and was comparable between ESCC (median of 7 months, IQR 2-25) and EAC (median of 9 months, IQR 3-26.3), p = 0.803. Advanced stage was associated with a worse prognosis (p = 0.037). The mean NLR(±SD) was 5.20 ± 6.8, with no significant difference between EAC and ESCC (4.5 ± 3.4 vs. 5.9 ± 9.2, p = 0.420) or between early or advanced stages (5.4 ± 8.1 vs. 4.7 ± 6.8, p = 0.732). The area under the curve for the NLR was 0.560 (95% CI: 0.374-0.746, p = 0.488). After adjusting for age, gender, TNM staging and grading, cox regression analysis showed that an increased NLR was a significant predictor of mortality, with an adjusted hazard ratio of 1.095 (p = 0.011). CONCLUSION: EC is quite uncommon in Lebanon despite a high prevalence of smoking and obesity. Advanced stage and high NLR were associated with a negative prognostic value.

Renal cell carcinoma management: real-world practice and challenges at a national level.

Renal cell carcinoma (RCC) management has seen a revolution over the last decades. Six Lebanese oncologists discussed recent updates in RCC management and outlined the challenges and future directions in Lebanon. Sunitinib continues to be a first-line choice for metastatic RCC in Lebanon, except for intermediate- and poor-risk patients. Immunotherapy is not always accessible to patients or selected routinely as first-line therapy. More data are needed on the sequencing of immunotherapy and tyrosine kinase inhibitor treatments and on the use of immunotherapy beyond progression and/or after failure of immunotherapy in the first-line setting. For second-line management, the clinical experience with axitinib for low tumor growth rate and nivolumab after progression on tyrosine kinase inhibitors make those two agents the most widely used. Several challenges affect the Lebanese practice, limiting the accessibility and availability of the medications. Reimbursement remains the most critical challenge, especially with the socioeconomic crisis of October 2019.

The first Middle East and North Africa expert consensus recommendations for management of advanced gastric cancer.

Gastric cancer (GC) ranks as the fifth most prevalent cancer and the fourth deadliest cancer worldwide. In the Middle East and North Africa (MENA) region, GC represents about 4.8% of cancer cases with more than 35,000 new cases in 2020. To strengthen and improve the management of this cancer in the region, a group of MENA experts in the field of GC developed the first MENA consensus recommendations for the management of advanced GC. A total of 28 statements were drafted, discussed and voted on, using a modified Delphi process, during a virtual consensus meeting. The statements addressed the areas of epidemiology, biomarkers and treatment.

A phase II single arm study of Nivolumab with stereotactic Ablative radiation Therapy after induction chemotherapy in CHOlangiocarcinoma (NATCHO).

BACKGROUND: Intrahepatic cholangiocarcinoma (CCA) is amongst the most common primary liver tumors worldwide. CCA carries a bad prognosis prompting research to establish new treatment modalities other than surgery and the current chemotherapeutic regimens adopted. Hence, this trial explores a new therapeutic approach, to combine stereotactic body radiation therapy (SBRT) and immunotherapy (Nivolumab), and asses its clinical benefit and safety profile after induction chemotherapy in CCA. METHODOLOGY: This is a Phase II open-label, single-arm, multicenter study that investigates Nivolumab (PD-1 inhibitor) treatment at Day 1 followed by SBRT (30 Gy in 3 to 5 fractions) at Day 8, then monthly Nivolumab in 40 patients with non-resectable locally advanced, metastatic or recurrent intrahepatic or extrahepatic CCA. Eligible patients were those above 18 years of age with a pathologically and radiologically confirmed diagnosis of non-resectable locally advanced or metastatic or recurrent intrahepatic or extrahepatic CCA, following 4 cycles of cisplatin-based chemotherapy with an estimated life expectancy of more than 3 months, among other criteria. The primary endpoint is the progression free survival (PFS) rate at 8 months and disease control rate (DCR). The secondary endpoints are overall survival (OS), tumor response rate (TRR), duration of response, evaluation of biomarkers: CD3 + , CD4 + and CD8 + T cell infiltration, as well as any change in the PD-L1 expression through percutaneous core biopsy when compared with the baseline biopsy following 1 cycle of Nivolumab and SBRT. DISCUSSION: SRBT alone showed promising results in the literature by both inducing the immune system locally and having abscopal effects on distant metastases. Moreover, given the prevalence of PD-L1 in solid tumors, targeting it or its receptor has become the mainstay of novel immunotherapeutic drugs use. A combination of both has never been explored in the scope of CCA and that is the aim of this study. TRIAL REGISTRATION: ClinicalTrials.gov NCT04648319 , April 20, 2018.

The impact of young age (< 40 years) on the outcome of a cohort of patients with primary non-metastatic breast cancer: analysis of 10-year survival of a prospective study.

BACKGROUND: The role of young age (< 40 years) at diagnosis as an independent risk factor for adverse outcomes in female patients with breast cancer has been highlighted in several studies. In this prospective study, we assessed the difference in 10-year survival between two groups of patients diagnosed with non-metastatic breast cancer based on an age cutoff of 40 years. We also assessed the impact of factors including tumor characteristics, molecular markers and immunohistochemical markers on survival outcomes, highlighting the interaction of those variables with age. METHODS: A total of 119 female patients with newly diagnosed non-metastatic breast cancer were recruited at the American University of Beirut Medical Center (AUBMC) between July 2011 and May 2014. Patients were recruited and divided into 2 age groups (< 40 and ≥ 40 years). In addition to clinical characteristics, we assessed immunohistochemistry including estrogen, progesterone and HER2 receptors, p53, cyclin B1, vascular endothelial growth factor receptor (VEGFR), and ki-67. Germline BRCA mutations were also performed on peripheral blood samples. Patient and tumor characteristics were compared between the age groups. 10-year overall survival (OS) and disease-free survival (DFS) were estimated accordingly. Cox regression analysis was performed in order to assess the effect of the different variables on clinical outcomes. RESULTS: After a median Follow-up of 96 (13-122) months, the estimated 10-year OS was 98.6% for patients ≥40 as compared to 77.6% in patients < 40 (p = 0.001). A similar trend was found for 10-year DFS reaching 90% for patients ≥40 and 70.4% for those < 40 (p = 0.004). On multivariate analysis for DFS and OS, only younger age (< 40 years), higher stage and triple negative phenotype among other parameters assessed significantly affected the outcome in this cohort. CONCLUSION: This prospective study confirms the association between younger age and adverse survival outcomes in patients with non-metastatic breast cancer. Future studies of the whole genome sequences may reveal the genomic basis underlying the clinical differences we have observed.

Classification of early-stage colon cancer with Immunoscore®: clinical evidence and case studies.

Immunoscore® is a digital pathology diagnostic immunoassay used to complement tumor node metastasis staging for the prediction of recurrence risk in patients with early-stage colon cancer. In combination with standard clinicopathological features, Immunoscore informs adjuvant chemotherapy decision-making for patients with early-stage colon cancer. Immunoscore has been validated in patients with stage II/III colon cancer and demonstrated to be a stronger prognostic factor for survival than tumor node metastasis staging alone. Immunoscore improves the prognostic definition of patients with colon cancer, the identification of those patients at high risk of tumor recurrence, and the ability to predict which patients will derive most benefit from the use of adjuvant chemotherapy. Immunoscore has robust analytical performance characteristics which include good interlaboratory reproducibility and overall assay precision.

Plain language summary Immunoscore^® is a digital pathology diagnostic test that is used in addition to standard tools for assessing the severity and aggressiveness of tumors in patients with early-stage colon cancer. Immunoscore helps clinicians decide whether chemotherapy would be appropriate in these cases and, if so, for what duration. The test is currently used for patients with stage II or stage III colon cancer to guide treatment and is a good indicator of prognosis in colon cancers, helping to identify which patients are at a higher risk of tumor recurrence and which patients might benefit most from chemotherapy. Immunoscore is also a reliable and precise test, even when performed on different portions of a tumor sample.

The first Middle East and North Africa expert consensus recommendations for the management of advanced colorectal cancer.

Colorectal cancer (CRC) is ranked as the third most prevalent and the second deadliest cancer worldwide. In the Middle East and North Africa (MENA) region, the number of CRC cases increased over the past decades and will nearly double by 2030. The lack of clear MENA guidelines for the management of patients with CRC represents a step backwards in the fight against this burden. Therefore a panel of 24 MENA experts in the field of gastrointestinal oncology developed, using a Delphi process, the first consensus recommendations for the management of patients with advanced CRC. Forty-seven different statements were formulated in the areas of epidemiology, screening, biomarkers and treatment. These recommendations will guide, standardize and unify the management of this cancer in the MENA region.

Adjusting the duration of androgen deprivation therapy (ADT) based on nadir PSA for high risk localized prostate cancer patients treated with definitive external beam radiation therapy and ADT.

BACKGROUND: A nadir Prostate-Specific Antigen (nPSA) of 0.06 ng/mL has been shown to be a strong independent predictor of biochemical recurrence-free survival (bRFS) in patients with intermediate or high-risk (HR) prostate cancer treated with definitive external beam radiation therapy (RT) and androgen deprivation therapy (ADT). We aimed to examine the association between the duration of ADT and bRFS in HR localized prostate cancer, based on nPSA. METHODS: Between 1998 and 2015, 204 patients with HR localized prostate cancer were identified. Of them, 157 patients (77.0%) reached the desired nPSA of < 0.06 ng/mL (favorable group), while 47 (23.0%) did not (unfavorable group). Duration of ADT varied among patients depending on physician preference, patient tolerance, and/or compliance. Survival outcomes were calculated using Kaplan-Meier methods and predictors of outcomes using multi-variable cox regression model. RESULTS: In the favorable group, ADT for at least 12 months lead to superior bRFS compared to ≤ 9 months of ADT (P = 0.036). However, no significant difference was seen when examining the value of receiving ADT beyond 12, 18, or 24 months, respectively. On univariate analysis for bRFS, the use of ADT for at least 12 months was significant (P = 0.012) as well as time to nadir PSA (tnPSA), (≤ 6 vs > 6 months); (P = 0.043). The presenting T stage was borderline significant (HR 3.074; 95% CI 0.972-9.719; P = 0.056), while PSA at presentation, Gleason Score and age were not. On multivariate analysis, the use of ADT for 12 months (P = 0.012) and tnPSA (P = 0.037) remained significant. In the unfavorable group, receiving ADT beyond 9 and 12 months was associated with improved bRFS (P = 0.044 and 0.019, respectively). However, beyond 18 months, there was no significant difference. CONCLUSION: In HR localized prostate cancer patients treated with definitive RT and ADT, the total duration of ADT may be adjusted according to treatment response using nPSA. In patients reaching a nPSA below 0.06 ng/mL, a total of 12 months of ADT may be sufficient, while in those not reaching a nPSA below 0.06 ng/mL, a total duration of 18 months is required.

Overview in Breast Cancer Screening in Lebanon.

Breast cancer (BC) is the most common cancer in women and men combined, and it is the second cause of cancer deaths in women after lung cancer. In Lebanon, the same epidemiological profile applies where BC is the leading cancer among Lebanese females, representing 38.2% of all cancer cases. As per the Center for Disease Control, there was a decline in BC mortality rate from 2003 to 2012 reflecting the adoption of national mammographic screening as the gold standard for BC detection by Western countries. The aim of this review study is to summarize current recommendations for BC screening and the available modalities for detecting BC in different countries, particularly in Lebanon. It also aims at exploring the impact of screening campaigns on BC early stage diagnosis in Lebanon. Despite the considerable debates whether screening mammograms provides more harm than benefits, screening awareness should be stressed since its benefits far outweigh its risks. In fact, the majority of BC mortality cases in Western countries are non-preventable by the use of screening mammograms alone. As such, Lebanon adopted a public focus on education and awareness campaigns encouraging early BC screening. Several studies showed the impact of early detection that is reflected by an increase in early stage disease and a decrease in more aggressive stages. Further studies should shed the light on the effect of awareness campaigns on early breast cancer diagnosis and clinical down staging at a national scope; therefore, having readily available data on pre- and post-adoption of screening campaigns is crucial for analyzing trends in mortality of breast cancer origin and reduction in advanced stages diseases. There is still room for future studies evaluating post-campaigns knowledge, attitudes, and practices of women having participated, emphasizing on the barriers refraining Lebanese women to contribute in BC screening campaigns.

Metabolic Factors Affecting Tumor Immunogenicity: What Is Happening at the Cellular Level?

Immunotherapy has changed the treatment paradigm in multiple solid and hematologic malignancies. However, response remains limited in a significant number of cases, with tumors developing innate or acquired resistance to checkpoint inhibition. Certain "hot" or "immune-sensitive" tumors become "cold" or "immune-resistant", with resultant tumor growth and disease progression. Multiple factors are at play both at the cellular and host levels. The tumor microenvironment (TME) contributes the most to immune-resistance, with nutrient deficiency, hypoxia, acidity and different secreted inflammatory markers, all contributing to modulation of immune-metabolism and reprogramming of immune cells towards pro- or anti-inflammatory phenotypes. Both the tumor and surrounding immune cells require high amounts of glucose, amino acids and fatty acids to fulfill their energy demands. Thus, both compete over one pool of nutrients that falls short on needs, obliging cells to resort to alternative adaptive metabolic mechanisms that take part in shaping their inflammatory phenotypes. Aerobic or anaerobic glycolysis, oxidative phosphorylation, tryptophan catabolism, glutaminolysis, fatty acid synthesis or fatty acid oxidation, etc. are all mechanisms that contribute to immune modulation. Different pathways are triggered leading to genetic and epigenetic modulation with consequent reprogramming of immune cells such as T-cells (effector, memory or regulatory), tumor-associated macrophages (TAMs) (M1 or M2), natural killers (NK) cells (active or senescent), and dendritic cells (DC) (effector or tolerogenic), etc. Even host factors such as inflammatory conditions, obesity, caloric deficit, gender, infections, microbiota and smoking status, may be as well contributory to immune modulation, anti-tumor immunity and response to immune checkpoint inhibition. Given the complex and delicate metabolic networks within the tumor microenvironment controlling immune response, targeting key metabolic modulators may represent a valid therapeutic option to be combined with checkpoint inhibitors in an attempt to regain immune function.

Hepatocellular Carcinoma Immunotherapy and the Potential Influence of Gut Microbiome.

Disruptions in the human gut microbiome have been associated with a cycle of hepatocyte injury and regeneration characteristic of chronic liver disease. Evidence suggests that the gut microbiota can promote the development of hepatocellular carcinoma through the persistence of this inflammation by inducing genetic and epigenetic changes leading to cancer. As the gut microbiome is known for its effect on host metabolism and immune response, it comes as no surprise that the gut microbiome may have a role in the response to therapeutic strategies such as immunotherapy and chemotherapy for liver cancer. Gut microbiota may influence the efficacy of immunotherapy by regulating the responses to immune checkpoint inhibitors in patients with hepatocellular carcinoma. Here, we review the mechanisms by which gut microbiota influences hepatic carcinogenesis, the immune checkpoint inhibitors currently being used to treat hepatocellular carcinoma, as well as summarize the current findings to support the potential critical role of gut microbiome in hepatocellular carcinoma (HCC) immunotherapy.

The Role of Gut Microbiota in Overcoming Resistance to Checkpoint Inhibitors in Cancer Patients: Mechanisms and Challenges.

The introduction of immune checkpoint inhibitors has constituted a major revolution in the treatment of patients with cancer. In contrast with the traditional cytotoxic therapies that directly kill tumor cells, this treatment modality enhances the ability of the host's immune system to recognize and target cancerous cells. While immune checkpoint inhibitors have been effective across multiple cancer types, overcoming resistance remains a key area of ongoing research. The gut microbiota and its role in cancer immunosurveillance have recently become a major field of study. Gut microbiota has been shown to have direct and systemic effects on cancer pathogenesis and hosts anti-tumor immune response. Many studies have also shown that the host microbiota profile plays an essential role in the response to immunotherapy, especially immune checkpoint inhibitors. As such, modulating this microbial environment has offered a potential path to overcome the resistance to immune checkpoint inhibitors. In this review, we will talk about the role of microbiota in cancer pathogenesis and immune-system activity. We will also discuss preclinical and clinical studies that have increased our understanding about the roles and the mechanisms through which microbiota influences the response to treatment with immune checkpoint inhibitors.

Proportion of cancers attributable to major lifestyle and environmental risk factors in the Eastern Mediterranean region.

Cancer is a major contributing cause of morbidity and mortality in the Eastern Mediterranean region. The aim of the current study was to estimate the cancer burden attributable to major lifestyle and environmental risk factors. We used age-, sex- and site-specific incidence estimates for 2012 from IARC's GLOBOCAN, and assessed the following risk factors: smoking, alcohol, high body mass index, insufficient physical activity, diet, suboptimal breastfeeding, infections and air pollution. The prevalence of exposure to these risk factors came from different sources including peer-reviewed international literature, the World Health Organization, noncommunicable disease Risk Factor Collaboration, and the Food and Agriculture Organization. Sex-specific population-attributable fraction was estimated in the 22 countries of the Eastern Mediterranean region based on the prevalence of the selected risk factors and the relative risks obtained from meta-analyses. We estimated that approximately 33% (or 165,000 cases) of all new cancer cases in adults aged 30 years and older in 2012 were attributable to all selected risk factors combined. Infections and smoking accounted for more than half of the total attributable cases among men, while insufficient physical activity and exposure to infections accounted for more than two-thirds of the total attributable cases among women. A reduction in exposure to major lifestyle and environmental risk factors could prevent a substantial number of cancer cases in the Eastern Mediterranean. Population-based programs preventing infections and smoking (particularly among men) and promoting physical activity (particularly among women) in the population are needed to effectively decrease the regional cancer burden.

Short-course radiation followed by mFOLFOX-6 plus avelumab for locally-advanced rectal adenocarcinoma.

BACKGROUND: Current standard practice for locally advanced rectal cancer (LARC) entails a multidisciplinary approach that includes preoperative chemoradiotherapy, followed by total mesorectal excision, and then adjuvant chemotherapy. The latter has been accompanied by low compliance rates and no survival benefit in phase III randomized trials, so the strategy of administering neoadjuvant, rather than adjuvant, chemotherapy has been adapted by many trials, with improvement in pathologic complete response. Induction chemotherapy with oxaliplatin has been shown to have increased efficacy in rectal cancer, while short-course radiation therapy with consolidation chemotherapy increased short-term overall survival rate and decreased toxicity levels, making it cheaper and more convenient than long-course radiation therapy. This led to recognition of total neoadjuvant therapy as a valid treatment approach in many guidelines despite limited available survival data. With the upregulation (PDL-1) expression in rectal tumors after radiotherapy and the increased use of in malignant melanoma, the novel approach of combining immunotherapy with chemotherapy after radiation may have a role in further increasing pCR and improving overall outcomes in rectal cancer. METHODS: The study is an open label single arm multi- center phase II trial. Forty-four recruited LARC patients will receive 5Gy x 5fractions of SCRT, followed by 6 cycles of mFOLFOX-6 plus avelumab, before TME is performed. The hypothesis is that the addition of avelumab to mFOLFOX-6, administered following SCRT, will improve pCR and overall outcomes. The primary outcome measure is the proportion of patients who achieve a pCR, defined as no viable tumor cells on the excised specimen. Secondary objectives are to evaluate 3-year progression-free survival, tumor response to treatment (tumor regression grades 0 & 1), density of tumor-infiltrating lymphocytes, correlation of baseline Immunoscore with pCR rates and changes in PD-L1 expression. DISCUSSION: Recent studies show an increase in PD-L1 expression and density of CD8+ TILs after CRT in rectal cancer patients, implying a potential role for combinatory strategies using PD-L1- and programmed-death- 1 inhibiting drugs. We aim through this study to evaluate pCR following SCRT, followed by mFOLFOX-6 with avelumab, and then TME procedure in patients with LARC. TRIAL REGISTRATION: Trial Registration Number and Date of Registration: ClinicalTrials.gov NCT03503630, April 20, 2018.

Management of patients with high-risk and advanced prostate cancer in the Middle East: resource-stratified consensus recommendations.

PURPOSE: Prostate cancer care in the Middle East is highly variable and access to specialist multidisciplinary management is limited. Academic tertiary referral centers offer cutting-edge diagnosis and treatment; however, in many parts of the region, patients are managed by non-specialists with limited resources. Due to many factors including lack of awareness and lack of prostate-specific antigen (PSA) screening, a high percentage of men present with locally advanced and metastatic prostate cancer at diagnosis. The aim of these recommendations is to assist clinicians in managing patients with different levels of access to diagnostic and treatment modalities. METHODS: The first Advanced Prostate Cancer Consensus Conference (APCCC) satellite meeting for the Middle East was held in Beirut, Lebanon, November 2017. During this meeting a consortium of urologists, medical oncologists, radiation oncologist and imaging specialists practicing in Lebanon, Syria, Iraq, Kuwait and Saudi Arabia voted on a selection of consensus questions. An additional workshop to formulate resource-stratified consensus recommendations was held in March 2019. RESULTS: Variations in practice based on available resources have been proposed to form resource-stratified recommendations for imaging at diagnosis, initial management of localized prostate cancer requiring therapy, treatment of castration-sensitive/naïve advanced prostate cancer and treatment of castration-resistant prostate cancer. CONCLUSION: This is the first regional consensus on prostate cancer management from the Middle East. The following recommendations will be useful to urologists and oncologists practicing in all areas with limited access to specialist multi-disciplinary teams, diagnostic modalities and treatment resources.

The Crosstalk between Microbiome and Immune Response in Gastric Cancer.

Gastric cancer is the end result of a complex interplay between host genetics, environmental factors, and microbial factors. The link between gut microbiome and gastric cancer has been attributed to persistent activation of the host's immune system by gut microbiota. The end result of this dysregulated interaction between host epithelium and microbes is a state of chronic inflammation. Gut bacteria can promote anti-tumor immune responses through several mechanisms. These include triggering T-cell responses to bacterial antigens that can cross-react with tumor antigens or cause tumor-specific antigen recognition; engagement of pattern recognition receptors that mediate pro-immune or anti-inflammatory effects or via small metabolites that mediate systemic effects on the host. Here we review the role of the gut microbiome including H. pylori and non-H. pylori gastric bacteria, the immune response, and immunotherapy using checkpoint inhibitors. We also review the evidence for cross talk between the gut microbiome and immune response in gastric cancer.

Resisting Resistance to Immune Checkpoint Therapy: A Systematic Review.

The treatment landscape in oncology has witnessed a major revolution with the introduction of checkpoint inhibitors: anti-PD1, anti-PDL1 and anti-CTLA-4. These agents enhance the immune response towards cancer cells instead of targeting the tumor itself, contrary to standard chemotherapy. Although long-lasting durable responses have been observed with immune checkpoints inhibitors, the response rate remains relatively low in many cases. Some patients respond in the beginning but then eventually develop acquired resistance to treatment and progress. Other patients having primary resistance never respond. Multiple studies have been conducted to further elucidate these variations in response in different tumor types and different individuals. This paper provides an overview of the mechanisms of resistance to immune checkpoint inhibitors and highlights the possible therapeutic approaches under investigation aiming to overcome such resistance in order to improve the clinical outcomes of cancer patients.

Exosomal Non Coding RNA in LIQUID Biopsies as a Promising Biomarker for Colorectal Cancer.

Colorectal cancer (CRC) is one of the most common cancers worldwide, with a high mortality rate, especially in those that are diagnosed in late stages of the disease. The current screening blood-based markers, such as carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9), have low sensitivity and specificity. Meanwhile, other modalities are either expensive or invasive. Therefore, recent research has shifted towards a minimally invasive test, namely, liquid biopsy. Exosomes are favorable molecules sought in blood samples, since they are abundant, stable in circulation, and harbor genetic information and other biomolecules that could serve as biomarkers or even therapeutic targets. Furthermore, exosomal noncoding RNAs, such as miRNAs, lncRNAs, and circRNAs, have demonstrated the diagnostic potential to detect CRC at an early stage with a higher sensitivity and specificity than CEA and CA19-9 alone. Moreover, they have prognostic potential that is TNM stage specific and could serve as predictive biomarkers for the most common chemotherapeutic drug and combination regimen in CRC, which are 5-FU and FOLFOX, respectively. Therefore, in this review, we focus on the role of these exosomal noncoding RNAs as diagnostic, prognostic, and predictive biomarkers. In addition, we discuss the advantages and challenges of exosomes as a liquid biopsy target.

The unveiling of a new risk factor associated with bladder cancer in Lebanon.

BACKGROUND: No accurate evaluation of smoking and water pollution on bladder cancer has been conducted in the Lebanese population. Our aim is to examine the significance of smoking and one of the main water pollutants Trihalomethanes (THM) on bladder cancer risk. METHODS: Population Attributable Fraction (PAF) was used to quantify the contribution of the risk factors smoking and THMs on bladder cancer in Lebanon. To calculate PAF for each risk factor, we used the proportion of the population exposed and the relative risk for each risk factor. Relative risks for each risk factor were obtained from published meta-analyses. The population at risk values were obtained from a report on chronic disease risk factor surveillance in Lebanon which was conducted by the World Health Organization between 2008 and 2009 and a national study by Semerjian et al. that conducted a multipathway exposure assessment of selected public drinking waters of Lebanon for the risk factors smoking and THMs, respectively. RESULTS: Bladder cancer cases that were the result of smoking in Lebanon among males and females are 33.4 and 18.6%, respectively. Cases attributed to mid-term exposure to THM contamination of drinking water is estimated at 8.6%. CONCLUSION: This paper further highlights the negative impact of smoking on bladder cancer risk and adds an overlooked and often underestimated risk that THMs have on this type of cancer. Thus, it is imperative that a national based study which assesses THM exposure by gender and smoking status be implemented to determine the real risk behind this byproduct.