IN late 2018, it was reported that badminton champion Datuk Lee Chong Wei had to undergo treatment for early-stage nose cancer.
The former World No. 1 has since bounced back after the diagnosis. His condition has thrown the spotlight on nasopharyngeal carcinoma (NPC), a type of nose cancer.
It is the fifth most common cancer in the country and the fourth most common among Malaysian Chinese men.
The ethnic link to NPC is undeniable. Internationally, the highest incidence of NPC among males has been recorded in Zhongshan City, China. The incidence rate among Malaysian Chinese is almost similar to that of Singaporean Chinese.
Mahkota Medical Centre ear, nose, throat, head and neck surgeon Dr Ram Kumar Sharma says besides ethnicity, age is also a risk factor.
As we age, more cells are damaged due to turnover, he explains. These damaged cells are susceptible and may mutate into cancer cells. This may occur independently or in tandem with other risk factors to accelerate the process.
There's also a genetic link. "In our clinical practice, we see NPC occurring in the family too," says Dr Ram.
NPC may not be easily spotted by the patient as it begins inside and behind the nose at the nasopharynx (a space at the junction between the nose and mouth). This spot is a junction of important structures (such as the skull bone, nerve fibres, the brain, ears and eyes) and the cancer can easily spread in these critical areas. In late stages, the cancer may spread to adjacent bones, the liver and lungs.
Patients usually come in with a one-sided, painless and progressive swelling of the neck.
In the early stages of NPC, this neck complaint may or may not be associated with nose, ear, face and head problems.
Dr Ram says almost 50 to 60 per cent of patients tend to be diagnosed at late stages.
"The site of origin is often hidden. Therefore, this does not trigger any warning signs, and symptoms such as neck swelling, ear blockage, reduced hearing or face numbness are often not investigated thoroughly."
This can also be attributed to a lack of awareness of NPC symptoms, he adds.
The key thing is to seek early consultation if one has any symptoms suggestive of NPC.
UNDERSTANDING THE CAUSES
The risk factors for NPC, as with any other cancers, can be classified into non-modifiable and modifiable.
Non-modifiable factors include age (more than 50 years old), gender (male), family history of NPC and race ( Chinese).
The modifiable factors include lifestyle (smoking, alcohol consumption), environmental risks (chemical/wood dust), infection caused by the Epstein-Barr virus and diet (excessive salt/ preserved food).
Dr Ram says while preserved and salt-cured foods such as fish, leafy vegetables and eggs are a staple diet for some people, when one analyses the dietary habits of NPC patients, there is an association between the disease and such foods.
"This observation is significant as it gives us a link between NPC patients. However, this does not mean someone who does not consume these foods will not get NPC," he stresses.
There are multifactorial causes for NPC and one has to be aware of the other modifiable and non-modifiable synergistic factors as well, he explains.
Treatment of NPC usually comprises radiotherapy alone or in combination with chemotherapy.
Dr Ram says prognosis is likely to be good if NPC is detected early.
"Please see your doctor if you have any worrying symptoms."
THE DIET FACTOR
A 2017 study published in the Chinese Journal of Cancer, found that people who consumed salted vegetables at least once a week were four times more likely to develop NPC compared to those who either never or rarely ate the ingredient. Salted vegetables are a common ingredient in Chinese cooking.
NPC has also been linked to a high consumption of cured meats, salted fish and fermented soy beans, all of which are very salty foods which are high in nitrates and nitrites, which create a reaction with protein to form nitrosamines. These can damage our DNA and lead to cancer.
Chinese salted fish, for example, is said to contain high amounts of nitrosamines compared to other types of salted fish and studies have indicated a high incidence of NPC among the boat people of Hong Kong where salted fish is a staple part of the daily diet given their lifestyle and living environment.
FAST FATS
*Around 5.2 per cent of Malaysian men and 1.9 per cent of Malaysian women had NPC between 2012-2016.
*A total of 4,597 cases of nasopharynx cancer were registered during that period with 73.1 per cent among males and 26.9 per cent among females.
*The incidence in males increases after age 25 and peaks at 65 years.
*The lifetime risk of NPC among Malaysian Chinese males is 1 in 108 while it's 1 in 341 among Malays.