Bladder Cancer in Lebanon: Incidence and Comparison to Regional and Western Countries

Uncovering the epidemiology of bladder cancer in the Arab world: A review of risk factors, molecular mechanisms, and clinical features

Objective

Bladder cancer (BC) is a significant public health concern in the Middle East and North Africa, but the epidemiology and clinicopathology of the disease and contributors to high mortality in this region remain poorly understood. The aim of this systematic review was to investigate the epidemiological features of BC in the Arab world and compare them to those in Western countries in order to improve the management of this disease.

Methods

An extensive electronic search of the PubMed/PMC and Cochrane Library databases was conducted to identify all articles published until May 2022, following the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines. A total of 95 articles were included in the final analysis after title, abstract, and full-text screening, with additional data obtained from the GLOBOCAN and WHO 2020 databases.

Results

Most of the included articles were case-control studies examining the risk factors and molecular mechanisms of BC. These studies originated from 10 different countries, with Egypt being the most active contributor. While BC in the Arab world shares some common risk factors with Western countries, such as smoking and occupational exposure, it also exhibits unique features related to schistosomiasis. The high mortality rates in this region are alarming and can be attributed to various factors, including the prevalence of smoking, the impact of schistosomiasis, a combination of genetic and socioeconomic factors, treatment shortages, and limited access to care or inadequate assessment of the quality of care.

Conclusion

Despite the relatively low incidence of BC in Arab countries, the mortality rates are among the highest worldwide. BC tends to be more aggressive in the Arab world, making it essential to implement strategies to address this burden.

Arab world's impact on bladder cancer research and opportunities for growth: A bibliometric review study

BACKGROUND

Bladder Cancer (BC) is a widespread form of cancer that affects over 1.6 million people globally. The majority of cases are diagnosed as urothelial carcinoma, with a higher likelihood of diagnosis in men and with increasing age. The Arab world (AW) is one of the regions with the highest incidence and mortality rates of BC, and the average age of diagnosis is between 40 and 49 years in North Africa and the Middle East. This study aims to assess the activity and distribution of BC publications in the AW.

METHODS

A systematic search across MEDLINE and Embase databases spanning 2007 to 2021 identified 1208 English-language articles on bladder cancer with Arab affiliations. The dataset was normalized against the average population and GDP (2007-2020) for 22 Arab countries. Statistical analyses via SPSS and visualizations with VOSviewer unveiled collaboration patterns and thematic trends in Arab bladder cancer research.

RESULTS

A total of 1208 BC publications were published in the AW, representing 0.24% of all biomedical publications. Egypt topped the list with the highest number of publications. The co-authorship analysis generated by VOSviewer revealed that out of 4766 authors, 161 met the minimum threshold of 5 publications.

CONCLUSION

The findings reveal that Egypt and Jordan are at the forefront of BC research in the region, while other Arab countries are lagging behind despite being heavily impacted by the disease. To drive progress in the field, it's important to uncover the obstacles impeding BC research in these countries and implement effective solutions to overcome them.

Cancer patterns in Iran: a gender-specific spatial modelling of cancer incidence during 2014-2017

BACKGROUND

Cancer is a significant public health concern and the second leading cause of death. This study aims to visualize spatial patterns of top common cancer types and identify high-risk and low-risk counties for these cancers in Iran from 2014 to 2017.

METHODS

In this study, we analyzed 482,229 newly diagnosed cancer cases recorded by the Iranian National Population-Based Cancer Registry from 2014 to 2017. We employed a purely spatial scanning model and local Moran I analysis to explore spatial patterns across Iran.

RESULTS

Approximately 53% of all cases were male. The average age of cancer diagnosis was 62.58 ± 17.42 years for males and 56.11 ± 17.33years for females. Stomach cancer was the most common cancer in men. The northern and northwestern regions of Iran were identified as high-risk areas for stomach cancer in both genders, with a relative risk (RR) ranging from 1.26 to 2.64 in males and 1.19 to 3.32 in females. These areas recognized as high-risk areas for trachea, bronchus, and lung (TBL) cancer specifically in males (RR:1.15-2.02). Central regions of Iran were identified as high-risk areas for non-melanoma skin cancers in both genders, ranking as the second most common cancer (RR:1.18-5.93 in males and 1.24-5.38 in females). Furthermore, bladder cancer in males (RR:1.32-2.77) and thyroid cancer in females (RR:1.88-3.10) showed concentration in the central part of Iran. Breast cancer, being the most common cancer among women (RR:1.23-5.54), exhibited concentration in the northern regions of the country. Also, northern regions of Iran were identified as high-risk clusters for colon cancer (RR:1.31-3.31 in males and 1.33-4.13 in females), and prostate cancer in males (RR:1.22-2.31). Brain, nervous system cancer, ranked sixth among women (RR:1.26-5.25) in central areas.

CONCLUSIONS

The study's revelations on the spatial patterns of common cancer incidence in Iran provide crucial insights into the distribution and trends of these diseases. The identification of high-risk areas equips policymakers with valuable information to tailor targeted screening programs, facilitating early diagnosis and effective disease control strategies.

Cost of bladder cancer in Lebanon before and after the economic collapse: a probabilistic modeling study

BACKGROUND AND OBJECTIVES

Lebanon has one of the highest incidence rates of bladder cancer (BC) in the world. In 2019, Lebanon's economy collapsed which majorly impacted healthcare costs and coverage. This study assesses the overall direct costs of urothelial BC in Lebanon, from the perspective of public and private third-party payers (TPP) and households, and evaluates the impact of the economic collapse on these costs.

METHODS

This was a quantitative, incidence-based cost-of-illness study, conducted using a macro-costing approach. Costs of medical procedures were obtained from the records of various TPPs and the Ministry of Public Health. We modeled the clinical management processes for each stage of BC, and conducted probabilistic sensitivity analyses to estimate and compare the cost of each stage, pre-and post-collapse, and for each payer category.

RESULTS

Before the collapse, the total annual cost of BC in Lebanon was estimated at LBP 19,676,494,000 (USD 13,117,662). Post-collapse, the total annual cost of BC in Lebanon increased by 768% and was estimated at LBP 170,727,187,000 (USD 7,422,921). TPP payments increased by 61% whereas out-of-pocket (OOP) payments increased by 2,745% resulting in a decrease in TPP coverage to only 17% of total costs.

CONCLUSION

Our study shows that BC in Lebanon constitutes a significant economic burden costing 0.32% of total health expenditures. The economic collapse induced an increase of 768% in the total annual cost, and a catastrophic increase in OOP payments.

Starvation-induced long non-coding RNAs are significant for prognosis evaluation of bladder cancer

BACKGROUND

Starving intratumoral microenvironment prominently alters genic profiles including long non-coding RNAs (lncRNAs), which further regulate bladder cancer (BCa) malignant biological properties, such as invasion and migration.

METHODS

Transcriptome RNA-sequencing data of 414 BCa tumor tissues and 19 normal tissues were obtained from TCGA database and paired samples of 132 BCa patients. A chain of in vitro validations such as qPCR, migration and invasion assays were performed to reveal the clinical relevance of AC011472.4 and AL157895.1.

RESULTS

A total of 11 lncRNAs were identified as starvation-related lncRNAs, of which AC011472.4 and AL157895.1 were relevant to overall survival of BCa patients. Besides, a starvation-related risk score model was established based on the levels of AC011472.4 and AL157895.1. BCa patients with higher levels of AL157895.1 were divided into the high-risk group and usually obtained higher mortality rate, but AC011472.4 was contrary. AL157895.1 expressed highly in BCa cell lines and tumour tissues, especially in patients with the advanced grade, stage and T-stage, while AC011472.4 showed the reversed result. Moreover, increased level of AL157895.1 was remarkably correlated to T-stage, muscle invasion status and distant metastasis. SiRNAs-mediated silence of AC011472.4 and AL157895.1 respectively increased and diminished invasion and migration properties of BCa cells.

CONCLUSIONS

In this study, we highlight the significant roles of AC011472.4 and AL157895.1 on evaluating prognoses of BCa patients and validate their correlation with various clinical parameters. These findings provide an appropriate risk score model for BCa clinical decision making.

AhRR methylation contributes to disease progression in urothelial bladder cancer

BACKGROUND

Bladder Cancer (BCa) is the tenth most incidental malignancy worldwide. BCa is mostly attributed to environmental exposure and lifestyle, particularly tobacco smoking. The Aryl Hydrocarbon Receptor Repressor (AhRR) participates in the induction of many enzymes involved in metabolizing carcinogens, including tobacco smoke components. Additionally, studies have shown that smoking demethylates the (AhRR) gene in blood, suggesting AhRR demethylation as a specific serum smoking biomarker.

OBJECTIVE

This study aimed to validate AhRR demethylation as a smoking biomarker in the target tissue and investigate its contribution to bladder carcinogenesis.

METHODS

AhRR percent methylation was tested for its association with patient smoking status and oncogenic outcome indicators, particularly p53, RB1, and FGFR3 activating mutations, muscle-invasiveness, and tumor grade, in 180 BCa tissue-based DNA.

RESULTS

Results showed significantly higher AhRR percent methylation in muscle-invasive compared to non-muscle invasive tumors (42.86% vs. 33.98%; p= 0.011), while lower AhRR methylation was significantly associated with FGFR3 Codon 248 mutant genotype compared to wild-type (28.11% ± 9.44 vs. 37.87% ± 22.53; p= 0.036). All other tested associations were non-statistically significant.

CONCLUSIONS

Although AhRR methylation did not predict smoking status in BCa tumors, it seems to play a role in carcinogenesis and disease progression. Our findings make a basis for further research.

Waterpipe Smoking among Bladder Cancer Patients: A Cross-Sectional Study of Lebanese and Jordanian Populations

Background

Bladder cancer (BC) is the second most reported cancer in Lebanon and the fifth in Jordan. Its risk factors are mainly smoking and occupational exposure to aromatic amines. In these countries where smoking and bladder cancer are highly prevalent, the role of waterpipe smoking (WPS) in bladder cancer is less investigated. We aim to compare two sets of patients between Lebanon and Jordan, focusing on their smoking habits, WP use, occupational exposure, and the grade/invasiveness of their bladder cancer.

Methods

This is a cross-sectional study that compares the smoking culture between two sets of populations with bladder cancer, from two different countries. We recruited 274 bladder cancer patients over the 18 years of age at the American University of Beirut Medical Center (AUBMC), and 158 bladder cancer patients over the age of 18 years at the King Hussein Cancer Center (KHCC).

Results

7.7% of Lebanese patients had significantly more positive family history of bladder cancer compared to 13.9% of Jordanian patients (p = 0.045). Another significant finding is that the majority of Lebanese patients 70.7% reported being frequently exposed to secondhand smoking, mainly cigarettes, versus only 48.6% of Jordanian patients (p < 0.001). The increasing smoking trend among Lebanese females is remarkably the highest in the region, which contributed to the overall increase in smoking rates in the country. 17.1% of the Lebanese smoking patients are mainly but not exclusively WP smokers of which 6.3% are daily WP smokers, similarly 17.1% of the Jordanian patients of which 3.2% are daily WP smokers. There were 71.5% of Lebanese patients who had a noninvasive BC versus 40% of Jordanian patients (p < 0.001), and more than one-third reported an occupational exposure to one of the risk factors of BC in both groups.

Conclusions

Bladder cancer incidence is on the rise in both Jordan and Lebanon along with different smoking types. It is necessary to impose prevention policies to prevent and control the high smoking prevalence. Bladder cancer invasiveness is higher in Jordan compared to universal data.

Triple-marker immunohistochemical assessment of muscle-invasive bladder cancer: Is there prognostic significance?

Background

Bladder cancer is the ninth most common cancer worldwide, and the third most common cancer in Lebanon. Immunohistochemistry (IHC) has been used to stratify muscle‐invasive bladder cancer (MIBC) into different subtypes. However, to our knowledge, there exists no study that investigates the use of this low‐cost technique to predict prognosis in bladder cancer patients in our region.

Aim

To examine the feasibility of low‐cost triple‐marker IHC assessment for MIBC subtyping in order to predict patients' survival and cisplatin sensitivity.

Methods and results

We collected the specimens of deceased patients diagnosed with MIBC on pathology at our institution. For each case, tumor tissue blocks were retrieved and stained for hematoxylin and eosin in addition to three molecular markers by IHC: cytokeratin 5/6, cytokeratin 14 staining basal BC, and GATA3 staining luminal BC. A cut‐off of ≥20% was set as positive. Kaplan‐Meier curves were built, factored by BC subtype, to predict overall survival (OS), disease‐specific survival (DSS), and progression‐free survival (PFS). Hazard ratios in Cox regression were also created accounting for oncological factors and BC subtype.

We categorized specimens as either luminal (GATA3 positive only) (n = 21; 56.7%) or as double‐positive (GATA3 and basal cytokeratin 5/6 or cytokeratin 14 positive) (n = 16; 43.3%). The overall median survival was similar between the two categories (27.0 ± 4.82 months). Numbers favored luminal disease for PFS (Breslow P = .032). After adjusting for covariates, luminal molecular expression predicted PFS (0.28; [0.09‐0.94]). Yet, the Cox model was not able to identify any predictors of OS or DSS.

Conclusion

Specimens enriched with only a luminal molecular profile were more likely to exhibit cisplatin sensitivity. Despite the absence of guidelines recommending the utilization of molecular profiling in clinic practice, triple‐marker IHC could serve as a potential low‐cost prognostic indicator to identify patients at high risk of progression.

Slow N-acetylation as a possible contributor to bladder carcinogenesis

Bladder cancer (BCa) is an exophytic tumor that presents as either noninvasive confined to the mucosa (NMIBC) or invading the detrusor muscle (MIBC), and was recently further subgrouped into molecular subtypes. Arylamines, major BCa environmental and occupational risk factors, are mainly metabolized by the genetically polymorphic N-acetyltransferases 1, NAT1 and NAT2. In this study, we investigated the association between N-acetyltransferases genetic polymorphism and key MIBC and NMIBC tumor biomarkers and subtypes. A cohort of 250 males with histologically confirmed urothelial BCa was identified. Tumors were genotyped for NAT1 and NAT2 using real-time polymerase chain reaction (PCR), and characterized for mutations in TP53, RB1, and FGFR3 by PCR-restriction fragment length polymorphism. Pathology data and patients' smoking status were obtained from medical records. Pearson χ² and Fisher exact tests were used to check for associations and interactions. Results show that NAT1 G⁵⁶⁰ A polymorphism is significantly associated with higher muscle-invasiveness (MIBC vs NMIBC; P = .001), higher tumor grade (high grade vs low grade; P = .011), and higher FGFR3 mutation frequency within the MIBC subgroup (P = .042; .027). NAT2 G⁸⁵⁷ A polymorphism is also found to be significantly associated with higher muscle-invasiveness (MIBC vs NMIBC; P = .041). Our results indicate that slow N-acetylation is a contributor to bladder carcinogenesis and muscle-invasiveness. These findings highlight NAT1 as a biomarker candidate in BCa and a potential target for drug development.

Epidemiological Study of Lung Cancer Incidence in Lebanon

Background and Objectives: Lung cancer (LC) is the most common cancer in the world. Developing countries in the Middle East and North Africa (MENA) region, including Lebanon, have witnessed a great increase in the incidence rates of this disease. The aim of our study is to investigate the incidence rates of lung cancer in Lebanon from 2005 to 2015 and to compare these rates to other countries from the MENA region and other regions of the world. Material and Methods: Lung cancer data for the years 2005-2015 were collected from the National Cancer Registry of Lebanon and stratified by gender and age group. Age-specific and age-standardized incidence rates were calculated and analyzed using joinpoint regression. Age-standardized incidence rates to the world population (ASR(w)) for other countries were obtained from two online databases. Results: Lung cancer ranked as the second most common cancer in Lebanon and accounted for 9.2% of all newly diagnosed cancers. Lung cancer ASR(w) showed a significantly increasing trend over the period studied for males and females. Lung cancer ASR(w) among males in Lebanon came second after Malta when compared to other MENA countries, but it was among the lowest when compared to non-MENA countries. For females, Lebanon ranked first when compared to other MENA countries but was among the lowest when compared to countries in other regions of the world. The lung cancer incidence rate increased with age in both sexes and 89.2% of patients were 50 years of age or older. Conclusion: Lebanon has the highest incidence of LC in females and the second highest for males in the MENA region. The lung cancer incidence rate is on the rise and older age groups are much more burdened by this disease than the young ones. Several risk factors, particularly smoking, play a role in increased LC incidence among the Lebanese population.