Gastric cancer location and histological subtype in Pacific people and Māori defies international trends

Abstract

Aims: Gastric cancer location and histopathology in Pacific people (mostly of Samoan, Tongan, Niuean, or Cook Islands origin) and Māori in New Zealand has not been specifically examined.

Methods: A retrospective review of all histologically-proven new cases of gastric adenocarcinoma and gastro-oesophageal adenocarcinoma at Middlemore Hospital (Auckland, New Zealand) from June 2003-June 2009 was conducted. Demographic data, clinical presentation, diagnostic/ staging investigations and surgical outcomes were recorded.

Results: There were 133 patients of whom 79 (59%) were male. Forty-nine (37%) patients were of Pacific ethnicity and 34 (26%) were Māori. Māori (59.3 years; p=0.01) and Pacific (64.5 years; p=0.01) patients were significantly younger at diagnosis compared to European patients (77.2 years). European patients had more proximal tumours (n=18; 47%) compared to Pacific (n=5; 10%) and Māori (n=4; 12%) patients (p= 0.01). Pacific (n=25; 51%) and Māori (n=21; 62%) patients had a significantly higher percentage of diffuse-type gastric cancer compared to European (n=7; 18%) patients. There was no difference in stage of presentation between ethnic groups.

Conclusions: Māori and Pacific patients present with gastric cancer at higher rates and at a younger age. They have a predominance of diffuse-type antral and gastric body cancers which stand in contrast to global trends in gastric cancer.