Gastric Adenocarcinomas in Central Tunisia: Evolution Specificities through Two Decades and Relation with Helicobacter pylori

Cancer mortality patterns in selected Northern and Southern African countries

BACKGROUND

Non-communicable diseases have been rapidly increasing in African countries. We provided updated cancer death patterns in selected African countries over the last two decades.

METHODS

We extracted official death certifications and population data from the WHO and the United Nations Population Division databases. We computed country- and sex-specific age-standardized mortality rates per 100 000 person-years for all cancers combined and ten major cancer sites for the periods 2005-2007 and 2015-2017.

RESULTS

Lung cancer ranked first for male cancer mortality in all selected countries in the last available period (with the highest rates in Réunion 24/100 000), except for South Africa where prostate cancer was the leading cause of death (23/100 000). Prostate cancer ranked second in Morocco and Tunisia and third in Mauritius and Réunion. Among Egyptian men, leukemia ranked second (with a stable rate of 4.2/100 000) and bladder cancer third (3.5/100 000). Among women, the leading cancer-related cause of death was breast cancer in all selected countries (with the highest rates in Mauritius 19.6/100 000 in 2015-2017), except for South Africa where uterus cancer ranked first (17/100 000). In the second rank there were colorectal cancer in Tunisia (2/100 000), Réunion (9/100 000) and Mauritius (8/100 000), and leukemia in Egypt (3.2/100 000). Colorectal and pancreas cancer mortality rates increased, while stomach cancer mortality rates declined.

CONCLUSION

Certified cancer mortality rates are low on a global scale. However, mortality rates from selected screening detectable cancers, as well as from infection-related cancers, are comparatively high, calling for improvements in prevention strategies.

Gastric cancer in Sub-Saharan Africa - a systematic review of primary data

Introduction

Gastric cancer (GC) is the third leading cause of global cancer-related mortality. Despite the shifting burden of GC to low-and middle-income countries, the data regarding incidence, treatment, and outcomes in these settings are sparse. The primary aim of this systematic review was to aggregate all available data on GC in sub-Saharan Africa (SSA) to describe the variability in incidence across the region.

Methods

Studies reporting population-based primary data on GC in SSA were considered. The inclusion was limited to primary studies published between January 1995 and March 2022 which comprised of adult patients in SSA with GC. Studies without accessible full text in either French or English language were excluded. Unadjusted GC incidence rates with their standard errors for each study were recalculated from the crude numerators and denominators provided in individual studies.

Results

A total of 5,626 articles were identified in the initial search, of which, 69 studies were retained. Reported incidence rates ranged from a high of 5.56 GC cases per 100,000 in Greater Meru Kenya to a low of 0.04 GC cases per 100,000 people in Benin City Nigeria. The overall crude pooled incidence was 1.20 GC cases per 100, 000 (95%CI 1.15-1.26) with a variability of 99.83% (I2 p < 0.001). From the 29 high-quality population-based registry studies the crude pooled incidence was 1.71 GC cases per 100,000 people (95%CI 1.56-21.88) with a variability of 99.60%.

Conclusion

This systemic review demonstrates that GC incidence is highly variable across SSA. The limited data on GC treatment, mortality, and survival presents a significant challenge to providing a complete epidemiologic description of the burden of GC in SSA. There is a need for further robust data collection, exploration, and research studies on cancer care in SSA, with continued assessment of primary data availability.

Selective expression of KCNA5 and KCNB1 genes in gastric and colorectal carcinoma

Background

Gastric and colorectal cancers are the most common malignant tumours, leading to a significant number of cancer-related deaths worldwide. Recently, increasing evidence has demonstrated that cancer cells exhibit a differential expression of potassium channels and this can contribute to cancer progression. However, their expression and localisation at the somatic level remains uncertain. In this study, we have investigated the expression levels of KCNB1 and KCNA5 genes encoding ubiquitous Kv2.1 and Kv1.5 potassium channels in gastric and colorectal tumours.

Methods

Gastric and colorectal tumoral and peritumoral tissues were collected to evaluate the expression of KCNB1 and KCNA5 mRNA by quantitative PCR. Moreover, the immunohistochemical staining profile of Kv2.1 and Kv1.5 was assessed on 40 Formalin-Fixed and Paraffin-Embedded (FFPE) gastric carcinoma tissues. Differences in gene expression between tumoral and peritumoral tissues were compared statistically with the Mann-Whitney U test. The association between the clinicopathological features of the GC patients and the expression of both Kv proteins was investigated with χ2 and Fisher’s exact tests.

Results

The mRNA fold expression of KCNB1 and KCNA5 genes showed a lower mean in the tumoral tissues (0.06 ± 0.17, 0.006 ± 0.009) compared to peritumoral tissues (0.08 ± 0.16, 0.16 ± 0.48, respectively) without reaching the significance rate (p = 0.861, p = 0.152, respectively). Interestingly, Kv2.1 and Kv1.5 immunostaining was detectable and characterised by a large distribution in peritumoral and tumoral epithelial cells. More interestingly, inflammatory cells were also stained. Surprisingly, Kv2.1 and Kv1.5 staining was undoubtedly and predominantly detected in the cytoplasm compartment of tumour cells. Indeed, the expression of Kv2.1 in tumour cells revealed a significant association with the early gastric cancer clinical stage (p = 0.026).

Conclusion

The data highlight, for the first time, the potential role of Kv1.5 and Kv2.1 in gastrointestinal-related cancers and suggests they may be promising prognostic markers for these tumours.

Retrospective epidemiological study on stomach cancer in a region of western Algeria: about 394 cases between 2011 and 2015

PURPOSE

Stomach cancer is a major global health problem; it is one of the ten most common cancers with poor survival, and its incidence is characterized by wide variation. The aim of this work is to carry out a retrospective epidemiological study on gastric cancer in the wilaya of Tlemcen (West Algeria) over a period of 5 years (2011-2015).

METHODS

The data set was provided by the cancer registry of the Tlemcen wilaya. The statistical analysis was performed using software SPSS.21.

RESULTS

During this period, 394 cases of gastric cancers were collected, including 199 patients with gastric adenocarcinoma (50.50%); gastric cancer was ranked in 5th rank of the ten most answered cancers in the wilaya. The average age of the patients was 60.5 ±  14.208 years (60.618 ±  13.556 men, 56.654 ±  14.8761 women) with an extremity ranging from 18 to 91 years. A predominance of men has been observed with 60.4% against 39.6% of women, with a sex ratio of 1.5 and a significant difference between the two sexes (p = 0.08). Patients over 50 years of age represented the predominant age group (73.4%). The tumor topography was antropyloric in 6.09% of the cases, and the vast majority of the diagnosed cases was in the local stage (17.01%).

CONCLUSION

Stomach cancer remains one of the top ten cancers in the Tlemcen willaya, so extensive research on the risk factors for gastric cancer remains important to plan effective preventive and curative strategies to reduce this burden.