Colorectal cancer below age 40 in the Kingdom of Saudi Arabia.

This study compares colorectal cancer from the King Faisal Specialist Hospital and Research Center (KFSHRC) Tumour Registry in patients under and over 40 years and contrasts the data with registry data from New Zealand (NZ). Between 1975 and 1989 622 patients were registered at KFSHRC and 528 were Saudi. Three hundred and twenty-one were male and 207 were female. The average ages were 55.3 and 49.6. One hundred and nineteen were less than 40 years. More patients with proximal lesions were less than 40 years. Of the young patients 8.3% had small tumours (less than 4 cm) compared with 24.9% of patients over 40. Mucinous and signet ring carcinomata were more common in the young. Tumours were less well differentiated in younger patients. There were more young patients with 'localized' disease and nodal involvement. Older patients had more distant metastases. Of patients registered in NZ 5.5% were young compared with 23% of Saudi patients. In both countries localized disease was more common in the young. Nodal involvement was more frequently seen in the young in the Kingdom of Saudi Arabia (KSA) whereas the opposite was true in NZ. Distant metastases were more common in the old in the KSA but there were more young patients with metastases in NZ. In both countries young females with rectal tumours were more common but this ratio was reversed in the old. This study suggests that colorectal cancer may be more aggressive in the young in KSA but there was no evidence that the disease was more aggressive in young New Zealanders. Differences in the epidemiology of the disease in the young and old were found in both countries.