Nose cancer is more accurately known as nasopharyngeal cancer, or nasopharyngeal carcinoma (NPC). Despite its common name, it does not arise from the visible part of the nose on the face — it develops in the nasopharynx, the upper part of the throat located behind the nose and above the back of the mouth, where the nasal passages connect to the throat. Cancer develops here when cells lining the nasopharynx begin to grow and multiply abnormally, forming a tumour.
Nasopharyngeal cancer is notable for its unusual geographic distribution: while rare in most parts of the world, it is significantly more common in Southern China, Hong Kong, and parts of Southeast Asia, including Singapore, where it occurs at rates many times higher than in Western countries. The most common form seen locally, undifferentiated carcinoma, is strongly associated with the Epstein-Barr Virus (EBV) — a very common virus that most people are exposed to at some point without ever developing cancer, but which plays a key role in nasopharyngeal cancer in genetically and environmentally predisposed individuals.
Types of Nose Cancer
Nasopharyngeal cancer is classified by the World Health Organization according to how the cancer cells appear under the microscope, which has an important bearing on its likely cause, behaviour and treatment response.
- Non-Keratinizing Undifferentiated Carcinoma: By far the most common type in Singapore and the wider Southeast Asian region, and is strongly associated with Epstein-Barr Virus infection. This type is generally very responsive to radiotherapy and chemotherapy.
- Non-Keratinizing Differentiated Carcinoma: Also linked to EBV infection, though somewhat less strongly than the undifferentiated form, and similarly sensitive to standard cancer treatments.
- Keratinizing Squamous Cell Carcinoma: A less common form in this region, more frequently associated with smoking and chronic irritation rather than EBV, and often behaves somewhat differently in terms of treatment response.
What Causes Nasopharyngeal Cancer
Nasopharyngeal cancer is thought to develop from a combination of viral, genetic and environmental factors acting together over time, rather than any single cause:
- Epstein-Barr Virus (EBV) infection: Nearly all cases of undifferentiated nasopharyngeal carcinoma in this region carry EBV genetic material within the tumour cells, strongly implicating the virus in how the cancer develops, even though EBV infection itself is extremely common and rarely causes any illness on its own.
- Genetic susceptibility: Certain inherited genetic traits, more common in people of Southern Chinese and Southeast Asian ancestry, appear to make some individuals more susceptible to developing nasopharyngeal cancer following EBV infection.
- Diet high in preserved and salted foods: Regular consumption of salted fish and other preserved foods, particularly during childhood, has been linked to a higher risk, thought to relate to cancer-forming compounds (nitrosamines) formed during the preservation process.
- Smoking: Tobacco use increases the risk of nasopharyngeal cancer, particularly the keratinizing squamous cell type, with risk rising according to how much and how long a person has smoked.
- Occupational and environmental exposures: Prolonged exposure to wood dust, formaldehyde, and certain industrial chemicals has been associated with an increased risk.
It's important to understand that having one or more of these risk factors does not mean a person will develop nasopharyngeal cancer, and many people diagnosed with the condition have no clearly identifiable cause — but understanding these factors helps explain why the condition is so much more common in certain populations and regions.
Symptoms of Nasopharyngeal Cancer
Early, small nasopharyngeal tumours often cause no symptoms at all, or only vague, intermittent symptoms that are easily mistaken for a common cold, sinus infection or allergy. This is one of the key reasons the condition is frequently diagnosed at a more advanced stage. As the tumour grows, it can cause a range of symptoms depending on which nearby structures are affected:
Nasal and Ear Symptoms
- Nasal blockage, often affecting one side more than the other
- Blood-stained nasal discharge, or blood-tinged saliva or sputum, particularly in the morning
- Reduced or muffled hearing on one side, or a persistent sensation of fullness in the ear
- Ringing in the ear (tinnitus), or recurrent middle ear infections, particularly in an adult where these are otherwise uncommon
Symptoms of More Advanced Disease
- A firm, painless lump in the neck, caused by cancer spread to nearby lymph nodes — often the first symptom a patient notices
- Persistent headache
- Double vision, or drooping of the eyelid, if the tumour affects the nerves controlling eye movement
- Facial numbness or altered sensation
- Difficulty opening the mouth fully (trismus), in more advanced local disease
Because early symptoms overlap so closely with common, benign conditions such as sinusitis or an ear infection, any of the above symptoms that are persistent, one-sided, or that do not resolve with standard treatment for a cold or sinus infection deserve prompt medical evaluation, particularly in individuals with risk factors for nasopharyngeal cancer.
Risk Factors for Nasopharyngeal Cancer
Several factors are known to increase the likelihood of developing nasopharyngeal cancer:
- Ethnicity and geography: People of Southern Chinese, Hong Kong, and Southeast Asian descent — including in Singapore — have a substantially higher incidence than most other populations worldwide.
- Family history: Having a first-degree relative with nasopharyngeal cancer increases individual risk, reflecting a shared genetic susceptibility.
- Epstein-Barr Virus infection: Given how common EBV infection is, this alone does not predict cancer, but the presence of the virus within tumour cells strongly implicates it as a contributing factor.
- Diet: Regular consumption of salted, preserved foods, particularly during childhood, is an established dietary risk factor in high-incidence regions.
- Smoking: Increases risk, particularly for the keratinizing squamous cell subtype, and may also affect treatment outcomes.
- Age and sex: Most commonly diagnosed in adults between 40 and 60 years of age, and occurs roughly twice as often in men as in women.
- Occupational exposure: Long-term exposure to wood dust, certain chemicals and industrial fumes has been linked to a modestly increased risk.
Stages of Nasopharyngeal Cancer
Once diagnosed, nasopharyngeal cancer is staged from I to IV based on the size and extent of the primary tumour, whether it has spread to nearby lymph nodes, and whether it has spread to distant parts of the body. Staging is central to planning the most appropriate treatment and understanding likely outcomes.
- Stage I: A small tumour confined to the nasopharynx, with no spread to lymph nodes or distant sites. Generally associated with excellent cure rates.
- Stage II: The tumour has begun to extend into nearby structures such as the oropharynx or nasal cavity, and/or has spread to lymph nodes on one side of the neck, but remains localised to the head and neck region.
- Stage III: The tumour has invaded further into surrounding structures, such as the base of the skull or paranasal sinuses, and/or has spread more extensively to lymph nodes in the neck, but there is still no spread to distant organs.
- Stage IV: The most advanced stage, involving extensive local invasion of surrounding structures (such as the brain, cranial nerves or eye socket), widespread lymph node involvement, or spread to distant organs such as the bone, lungs or liver.
Possible Complications of Nasopharyngeal Cancer
Both the cancer itself and its treatment can lead to complications, which is why ongoing specialist follow-up is an important part of care throughout and after treatment:
- Local invasion of nearby structures: Because the nasopharynx lies close to the base of the skull, advanced tumours can invade nearby cranial nerves, the eye socket, or brain-related structures, causing symptoms such as double vision, facial numbness or hearing loss.
- Distant metastasis: Nasopharyngeal cancer can spread to distant sites, most commonly the bones, lungs and liver, particularly in more advanced cases.
- Hearing loss and ear problems: Both the tumour itself and radiotherapy directed at the area can affect hearing and middle ear function over time.
- Dry mouth (xerostomia): Radiotherapy can affect the salivary glands, leading to persistent dry mouth, which can in turn increase the risk of dental problems if not proactively managed.
- Difficulty opening the mouth (trismus): Radiation-related stiffness of the jaw muscles can develop after treatment, which is why jaw-stretching exercises are often recommended during and after radiotherapy.
- Hypothyroidism: Radiotherapy to the neck can affect thyroid gland function over time, so periodic thyroid function monitoring is typically part of long-term follow-up.
How Nasopharyngeal Cancer Is Diagnosed
If nasopharyngeal cancer is suspected, based on persistent symptoms or a neck lump, a series of assessments are used to confirm the diagnosis and determine the extent of disease.
- Nasal Endoscopy: A thin, flexible tube with a camera and light is passed through the nose to directly examine the nasopharynx for any visible abnormality or mass.
- Biopsy: A small tissue sample is taken from the nasopharynx, usually during endoscopy, and examined under a microscope to confirm the diagnosis and identify the specific cancer type.
- Fine Needle Aspiration of Neck Lump: If a neck lump is present, a fine needle may be used to sample cells from the lymph node to check whether the cancer has spread there.
- Blood Test for EBV DNA: Measures the level of Epstein-Barr Virus genetic material circulating in the blood, which can support the diagnosis and is also used to help monitor response to treatment and check for recurrence afterward.
- MRI (Magnetic Resonance Imaging): Provides detailed images of the nasopharynx and surrounding soft tissue, helping to assess the size of the tumour and whether it has spread to nearby structures — an important step in accurate staging.
- PET-CT Scan: A whole-body scan used to check for spread to lymph nodes or distant organs, particularly important in more advanced or higher-risk cases.
Reducing Your Risk of Nasopharyngeal Cancer
While nasopharyngeal cancer cannot always be prevented, particularly given the role of genetic susceptibility, several measures may help lower your risk:
- Limit salted and preserved foods: Reducing regular consumption of salted fish and other preserved foods, particularly for children in higher-risk families, may help lower long-term risk.
- Avoid smoking: Not smoking, or quitting if you currently smoke, reduces your risk of nasopharyngeal cancer as well as many other cancers.
- Be mindful of occupational exposures: If your work involves wood dust, formaldehyde or similar substances, following recommended workplace safety measures can help reduce exposure.
- Know your family history: If you have a first-degree relative with nasopharyngeal cancer, discuss this with your doctor, as it may be reasonable to be more vigilant about relevant symptoms.
- Seek prompt evaluation of persistent symptoms: Because early detection significantly improves outcomes, don't dismiss persistent one-sided nasal blockage, blood-stained discharge, unexplained neck lumps or hearing changes as "just a cold" — especially if they don't resolve as expected.
