[Dietary risk factors of undifferenced nasopharyngeal carcinoma : a case-control study]

The incidence of nasopharyngeal carcinoma (NPC) is relatively high in Maghreb countries. This cancer is a model of multifactorial oncogenesis, but the role of food as risk factor in ethiopathogenesis of this tumor is not negligible.

To identify the association between risk of NPC and some dietary factors in Morocco.

It is a case-control study including all new cases of NPC in our department between December 2009 and May 2010. Frequency consummation of foods was compared between cases and controls matched for age, sex and socio economic level. A high frequency consummation of a food was defined as consumption once or more by a week. Some traditional foods in Moroccan cooking like Harissa (hot red pepper), Qadid (mutton dried and salted), Khlii (dried meat, salted, spiced cooked and preserved in a mixture of oil and rendered beef fat) and Smen (rancid butter) were analyzed in this study. A conditional logistic regression was used to identify the association between dietary factors and the risk of NPC.

Cases were more likely to have high frequency consumption of Harissa, Smen and Black Pepper, and less frequency consumption of fruts and vegetables. There was significant association between the risk of NPC and the frequency consumption of Qadid, khlii and cooking with olive oil.

Some of these risk factors (Harissa, Black pepper) were found in 3 North Africain studies. This study indicates the involvement of dietary factors, and thus the lifestyle in the development of NPC and the need of biochemical analysis of food specimens to search for the carcinogenic agents.