High Incidence of Esophageal Cancer in Women in Eritrea and Its Potential Link to Low Age at Menopause: Evidence from a 10-Year Retrospective Data Analysis.

Background: Detecting a group of esophageal cancer (EC) cases in endemic regions is essential in identifying high-risk populations and executing appropriate interventions. The main aim of this study was to determine the epidemiology of EC in Eritrea. Methods: A retrospective (period: 2011 - 2021) study was carried out by abstracting data on EC patients from the logbook kept at the National Health Laboratory (ENHL). Information on socio-demographic, clinical history, and biopsy analysis findings was collected. For the statistical assessment of data, the End Results (SEER) Joinpoint Regression Program (V.4.5.0.1) was used to calculate crude incidence rate (CIR), age-adjusted incidence rate (ASR), and estimated annual percentage change (EAPC) by sex, age, and histotype. Results: A total of 189 patient's samples (134 (70.9%) females vs. 55 (29.1%) males, ratio 2.43 : 1) were evaluated. Of the 155 patients with EC, 44 (28.4%) and 111 (71.6%) were diagnosed with esophageal adenocarcinoma (EAC) and esophageal squamous cell carcinoma (ESCC), respectively (AC/ESCC ratio, 0.4). The median age (IQR) of patients with EC was 60 years (46.0 - 70 years) - (males 62 (IQR: 49.0 - 77 years) vs. females 60 (IQR: 46 -67 years), p-value =0.43. Within age bands, the F: M ratios in patients with ESCC were as follows: >20 -29 years =2: 1; 30-39 years =8 : 1; 40 - 49 years =10.5 : 1; 50-59 years =6.67 : 1; 60-69 years =3.25.1; 70-79 years =1.5 : 1 and>80 years =2 : 1. The all-age CIR and ASR for EC were 0.468 per 100 000 and 2.281 per 100 000 persons, respectively. Similarly, the all-age ASR for both males and females was 2.88 per 100 000 and 1.61 per 100 000. Over the study period, the EAPC for all cases was -3.0% (95% CI, -11.3 to 6.1, p-value =0.455). Conclusion: In large part, EC is a women's disease in Eritrea. The unusually high incidence of ESCC and the high female-to-male ratio point at sex-dependent exposures as a major driver of the EAC epidemic in the country. Therefore, research on the risk factors of EC in Eritrea is urgently needed.