New classification of oesophageal and gastric carcinomas derived from changing patterns in epidemiology

The current ICD-O classification of carcinomas of the oesophagus and stomac h causes epidemiological and clinical confusion. This study compares the ep idemiological and clinical features of each subtype and subsite of adenocar cinomas of the oesophagus and stomach, to assess requirements for a new cla ssification of these carcinomas, Data were extracted with appropriate valid ity checks on all cases of oesophageal and gastric carcinomas identified th roughout the period 1974-1993 by the Merseyside and Cheshire Cancer Registr y, which covers a population of 2.5 million. The incidence of adenocarcinom as of the lower oesophagus and cardia trebled in males, and doubled in fema les, whereas adenocarcinoma of the subcardia region of the stomach declined in both sexes. Adenocarcinomas of the lower oesophagus and of the cardia w ere similar for median age at diagnosis, male to female ratio, percentage o f patients who smoked and survival; both were significantly different from carcinomas of the subcardia in these respects. These data imply that adenoc arcinomas of the lower oesophagus and cardia are the same disease. A new su bsite classification of oesophageal and gastric carcinomas is proposed that includes the gastro-oesophageal junction as a distinct subsite, to facilit ate surveillance, management and research.