Nasopharyngeal Carcinoma (NPC)

Nasopharyngeal Carcinoma (NPC) is the 6th mostneck lump, reduced hearing in one ear, nose bleeds,
common cancer among males in Singapore. Thisblood stained postnasal drip, blocked nose, headaches
disease hits hard because the peak incidence occursand double vision. The symptoms can be quite
in people who are in the prime of their working andnon-specific and there seems to be a tendency for
family lives. In Singapore, it is the second and thirdpatients to seek medical attention late. Even doctors
commonest cancer in males aged 15 to 34 years andcan be misled, leading to a delay in referring the patient
35 to 64 years respectively. The key to theto the specialist. A Singapore study showed that in
management of NPC is early detection. There is anearly one fifth of NPC patients, the diagnosis was
90% cure rate if the disease is treated at an earlydelayed by an average of 7.2 months due in part to
stage.clinicians not considering a diagnosis of NPC. It is for
This cancer has a distinct racial and geographicalthis reason that NPC is commonly diagnosed at a late
distribution. The highest incidence of NPC is in thestage (stage 3 or 4). This is unfortunate because the
Southern part of China (Guangdong province) andcure rate after treatment for stage 3 is only 60% and
Hong Kong hence the name "Cantonese Tumour". Theit drops to below 50% for stage 4 disease. On the
incidence is also high among North Africans, the Inuitsother hand, the cure rate for the earliest stage disease
of Alaska and the Chinese in South East Asiancan be in excess of 90%.
countries. About 92% of NPC sufferers in SingaporeThe best way to examine the nasopharynx is via a
are Chinese while 6% and 1% are Malay and Indiannasoendoscopy done by an ENT specialist in the clinic.
respectively. NPC is three times more common in men.A biopsy is done if a suspicious mass or irregularity is
What causes NPC?seen in the nasopharynx. Patients with NPC may also
It is known that NPC is caused by the Epstein Barrhave high titres of certain antibodies to EBV in their
Virus (EBV). This virus is extremely common and moreblood. Blood tests for these antibodies are available
than 90% of people are infected with the virus by thecommercially and can be used to screen for NPC in
time they reach adulthood. Infection with EBV causesselected high risk patients. An MRI scan with contrast
a minor flu like illness in children and occasionally ais a useful adjunct in NPC detection because it can
systemic disease called glandular fever in teenagerssometimes show up a growth even when the
and young adults. EBV persists in white blood cells in anasopharynx looks ‘normal' on nasoendoscopy.
dormant phase after the initial infection. TheTreatments for NPC
mechanism by which this virus subsequently causesNPC tumour cells are very sensitive to radiation hence
NPC in people is not fully understood and is currentlythe conventional treatment for early stage NPC is
under intense scrutiny by scientists and researchers.definitive radiation therapy (RT). Late stage disease is
The suspicion that NPC is also associated with thetreated with a combination of radiation and
consumption of preserved foods like salted fish camechemotherapy. During treatment, there is a significant
about because of the high incidence of the diseaseirradiation of the adjacent structures in the head and
among the boat people of Hong Kong. It is theorizedneck leading to potential RT long term effects like dry
that carcinogens released during the cooking ormouth, hearing loss, poor vision and temporal lobe
consumption of these foods primes the cells in thenecrosis. Improvements in RT equipment over the past
nasopharynx for EBV to cause cellular malignant10 years has reduced salivary flow continues to be a
change. Consumption of these foods at a young ageproblem in majority of patients. Surgical removal of the
is also thought to be a significant risk factor (weaningtumour is a difficult operation and is reserved for
children with salted fish was a common practice indisease that recurs after radiation and chemotherapy.
Southern China and Hong Kong)These surgeries are usually performed in selected
Genes play a significant role in NPC. A study done inpatients. It is a keyhole (scarless) procedure for
Singapore documented that 15.5% of first degreesurgically removing NPC that recurs after primary
relatives of NPC patients subsequently got thetreatment with radiation and chemotherapy.
disease. The mean interval to getting NPC betweenThis disease can be defanged if detected early. Public
affected siblings was 5.3 years while that betweeneducation regarding the symptoms of NPC is one way
affected parent and child was 24.5 years.to bring the patients in early. High risk groups like first
How is NPC diagnosed?degree relatives of patients with NPC should be
NPC can be difficult to detect because it grows in ascreened for the disease as soon as possible. Doctors
‘hidden' area at the back of the nose called theand primary care physicians should be thoroughly
nasopharynx. The problem is confounded by the factfamiliar with the symptoms and signs NPC and have a
that individuals with early disease may not havehigh index of suspicion for this disease.
symptoms. More advanced disease can present as a