Primary gastrointestinal cancers in the Western Region of Saudi Arabia. Is the pattern changing?

OBJECTIVE To determine the age, sex and relative frequencies of various gastrointestinal malignancies in patients registered with the National Cancer Registry from the Western Region of Saudi Arabia from January 1994 till December 1997, and compare this data with previous hospital based studies about the pattern of these malignancies in Saudi Arabia. METHODS A National Cancer Registry was established in Saudi Arabia in 1992, and since 1st January 1994 all cancer cases in Saudi Arabia have been registered with the National Cancer Registry. All National Cancer Registry data on patients with primary gastrointestinal cancers from the Western Region of Saudi Arabia from January 1994 till December 1997 was retrieved and analyzed according to ethnic origin, site, age, sex and relative frequencies of various tumors. RESULTS Out of a total of 1833 cases with primary gastrointestinal malignancies 1207 (66%) were Saudis, while the rest were Non-Saudis. Colorectal cancer was the the most common malignancy found in both population groups accounting for 28.5% of cases in Saudis and 36% in Non-Saudis. Malignancies of liver, stomach and esophagus followed in decreasing frequencies. The mean age of the Saudi population was 58+16 years (standard deviation) with male to female ratio of 1.67:1. About 80% of the patients were above 40 years of age and the peak of onset for most of the tumors was between 50 and 70 years of age. CONCLUSIONS This study highlights that colorectal cancer is the most common gastrointestinal malignancy seen in the Western Region of Saudi Arabia followed by hepatocellular carcinoma. This is in sharp contrast to the previous hospital based studies from Saudi Arabia and national trends as seen in the cancer incidence report from the National Cancer Registry of Saudi Arabia. The factors for this changing pattern of gastrointestinal malignancy remain to the determined.