The incidence and patterns of gastric cancers in Sri Lanka from 2001 to 2012: Analysis of National Cancer Registry Data.

Abstract

Varying patterns in incidence of gastric cancer (GC) have been reported globally. We aimed to examine the trends of GC incidence in Sri Lanka. All newly diagnosed patients with GC in Sri Lanka during 2001-2012 included in the National Cancer Registry were analyzed. Joinpoint regression analysis was used to determine the trends in incidence by age and gender. The minimum number of joinpoints were added to the model and statistical significance was checked using the Monte-Carlo permutation method. Overall, 3353 (male : female=2.7:1, mean age: 59.5 years) GCs were included in the analysis. Histology findings were available in 2835 patients. Of those, 14.3% (n=404) were classified as nonspecified neoplasm/carcinoma. Of the remaining 2431 patients, majority (84.1%, n=2044) were adenocarcinoma/its variants and 9.4% (n=228) were squamous cell carcinoma. The WHO age-standardized incidence of GC was found to have significantly increased from 1.06 in 2001 (95% CI=0.9-1.21) to 2.41/100000 population in 2012 (95% CI=2.2-2.61); with an estimated annual percentage change (EAPC) of 7.7 (95% CI=6.1-9.4). Highest incidence of GC was seen in 65-69 year age group (8.2/100000). The proportional rise in incidence was higher for females (from 0.5 to 1.36, EAPC: 9.0 [95% CI=6.4-11.8], P<.05 for trend) compared with males (from 1.71 to 3.66, EAPC: 7.5 [95% CI=5.5-9.6], P<.05 for trend). A rise in the incidence of GC was noted in Sri Lanka during the period 2001-2012, which was predominately observed in females. A combination of true increase in incidence and improved reporting may have contributed to this increase. Future studies analyzing tumor characteristics and mortality would enable better understand the burden of GC and potential underlying reasons.