Causes & Risk Factors of NPC

What factors put you at risk for nasopharyngeal cancer?

The causes of Nasopharyngeal Cancer (NPC) include Epstein Barr Virus infection, ethnicity, age and gender, family history, and environmental factors.

Research confirms that Chinese individuals are particularly susceptible to developing NPC. Inuit, North African, Portuguese as well as those from Mediterranean regions, the Middle East, Brazil, and a small pocket in Northern India are also all highly susceptible.

Multiple Epstein-Barr Virus (EBV) DNA copies are found in almost every nasopharyngeal tumor cell, including those in the early stage. By comparison, there is no EBV DNA in healthy nasopharyngeal epithelial cells. These findings suggest EBV plays a critical role in the early-stage formation of NPC.

RISK FACTORS

VIRAL INFECTION

Epstein-Barr (EBV) was classified by the International Agency for Cancer Research (IARC) as a Class I carcinogenic factor for NPC in 1997. However, NPC has a multifactorial etiology that includes genetic and environmental factors.

ETHNIC BACKGROUND

NPC is prominent in certain ethnic groups, suggesting the likelihood of genetic changes within these groups.

Chinese individuals with a family history of NPC are at a significantly higher risk compared to those without.

AGE & GENDER

Age and gender also contribute to the risk of developing NPC.

Incidence rates rise sharply after age 30 and peak between ages 50 and 55.

Men are three times more likely to develop NPC than women.

FAMILY HISTORY

In endemic regions, the risk for developing NPC is two to fifteen times greater for a person with a first-, second- or third-degree relative with NPC.

ENVIRONMENTAL FACTORS

According to the American Cancer Society, dietary intake of nitrite and nitrosamine (found in Cantonese salted fish and preserved foods), is closely linked to developing NPC.

Occupational exposures to wood dust and formaldehyde are also co-factors for developing NPC. The World Health Organization’s International Agency for Research on Cancer (IARC) classifies both outdoor air pollution and particulate matter (PM) as Class I carcinogens.