A population-based study on intestinal and diffuse type adenocarcinoma of the oesophagus and stomach in the Netherlands between 1989 and 2015

Aim To investigate the nationwide time trends in incidence and survival of oesophageal and gastric adenocarcinomas according to the Laurén classification (intestinal, diffuse and mixed type). Methods All patients diagnosed in the Netherlands with oesophageal or gastric adenocarcinoma between 1989 and 2015 were included. A syntax was developed to determine the histological subtype based on pathology reports as archived in the Dutch pathology registry. These reports were linked to individual data from the Netherlands Cancer Registry. Relative survival was used to assess survival. Results The histological subtype could be determined in 18.691 (84.1%) oesophageal and in 32.312 (83.5%) gastric adenocarcinomas. Among these, 79% were intestinal and 21% diffuse type in oesophageal cancers, compared to 55% intestinal and 44% diffuse type in gastric cancers. Relative median survival of intestinal type tumours was longer than that of diffuse type tumours, that is, 12.1 versus 9.4 months for oesophageal carcinomas, and 10.1 versus 7.6 months for gastric carcinomas, respectively. Between 1989 and 2015, the relative median survival of non-metastatic intestinal and diffuse type oesophageal adenocarcinoma improved from 12.0 to 30.0 months, and from 12.0 to 19.2 months, respectively. The same was true for intestinal type gastric carcinoma (from 22.8 to 27.6 months) but for diffuse type gastric carcinoma, the increase was less (from 16.8 to 18.0 months). Conclusion In this nationwide study, histological subtypes of oesophageal and gastric adenocarcinomas differed in incidence and survival times. These findings may call for a differentiated treatment approach.