IF you’re not southern Chinese, chances are nasopharyngeal carcinoma (NPC) is the biggest killer cancer you’ve never heard of. If you are southern Chinese, then it’s a killer cancer you really should have heard of, because your chances of getting it could be 25 times higher than other people.

    Nicknamed Cantonese cancer, NPC affects the nasopharynx: That’s the part of the head behind the nose, and above and behind the mouth.

    Although it mainly affects people from Guangdong, Guangxi and Hainan, it accounts for 18 percent of all cancer cases in China. It also affects younger adults more than most other cancers, striking most commonly in their 30s and 40s.

    And the problem is, NPC remains fiendishly hard to detect because most of its symptoms can easily be mistaken for those of far more benign conditions.

    These include inflammation of the middle ear, potentially causing ear blockage; hearing loss and tinnitus, but only on one side; fever; nasal obstruction; nosebleeds; and headaches.

    Precisely what causes a person to develop NPC is unknown, but medical consensus points to three factors. “Number one is racial,” said Dr. Peter Teo Man-lung, an oncologist at the Central Comprehensive Cancer Center in Hong Kong. “Certain southern Chinese are predisposed to developing NPC.” So if a close relative has had the disease, it makes sense to get screened for it.

    The second is infection by the ubiquitous Epstein-Barr virus, a member of the herpes family, which infects most people at some point in their lives and is associated with various cancers.

    The third is environmental factors, mainly diet. The key suspect is salted food — both in one’s ancestral diet and when fed to infants — and in particular a chemical compound called nitrosamine, a by-product of the preservation process.

    (SD-Agencies)