[Gastrointestinal non-hodgkin's lymphoma: general epidemiology and epidemiologic data based on 100 Lebanese cases seen between 1965 and 1991].

It is classical to separate gastro-intestinal non Hodgkin Lymphomas into two epidemiological profiles: 1--an "occidental" type frequently encountered in West countries (Europe and USA); 2--an "occidental" type which is dominant in the Middle East regions and is distinguished from the occidental type by the following features: the younger age of patients; the rarity of gastric involvement compared to the small intestinal involvement; the prevalence of Immuno Proliferative Small Intestinal Disease within the small intestinal non Hodgkin lymphomas. An epidemiological study was done on 100 cases of digestive non Hodgkin lymphomas seen in Lebanon between 1965 and 1991 in hospitals affiliated with Saint-Joseph University. The statistical analysis of our study leads to several conclusions: 1--the ISPID is disappearing in Lebanon during the last twenty-five years; 2--the site of gastrointestinal involvement is changing with time, the small intestinal involvement becoming more rare and the gastric involvement more frequent. So during this twenty-five years period, there was an occidentalization of the epidemiological profile. This varying pattern with time in the epidemiology of gastrointestinal non Hodgkin lymphomas could be due to changing in the environmental factors like the intestinal bacterial and parasitological infestation.