Nose cancer screening – Who should go for it?

Many people are unaware of what nasopharyngeal carcinoma (NPC) is and may wonder whether they should go for NPC screening, like one should do for colon or prostate cancer. For more information on NPC, visit https://drganent.com/head-neck-ent-clinic-singapore.html. In this blog, Dr Gan explains the risk factors for NPC and who should consider NPC screening.

What is nasopharyngeal carcinoma?

The nasopharynx is the area at the back part of your nasal cavity. Nasopharyngeal carcinoma (NPC) is cancer of the nasopharynx. It is often known as “nose cancer” and is the most common head and neck cancer in Singapore.

What are the risk factors for NPC?

The 3 known risk factors for NPC are:

1. Framily history of NPC
   People with family members with NPC are more likely to have NPC. It is not known if this due to genetic factors, shared dietary habits or environment, or a combination of both. Studies have shown that a person with certain inherited tissue types makes him or her more susceptible to NPC.
2. Epstein-Bar virus (EBV) infection
   EBV is a very common viral infection and most people have been exposed to it. However, in some people (perhaps due to their genetic makeup) who are exposed to this virus, their body reacts in a way that makes them more susceptible to NPC
3. High salt-cured fish and meat diet
   It is known that populations with early exposure to such diet, e.g preserved vegetables or salted fish are more likely to have NPC

What are the symptoms of NPC?

As the nasopharynx is located in a deep part of the nose, patients with early stage NPC may not have any symptoms. Symptoms usually appear when the cancer is bigger or starts pressing on surrounding structures. In fact, we know that almost 75% of NPCs are diagnosed when the cancer has spread to the lymph node in the neck. Hence the most common symptom is a lump or multiple lumps in the neck.

Other possible symptoms of NPC include:

• Hearing loss, ear fullness, ringing in the ear
• Blocked nose
• Blood stain in the saliva or nose
• Nosebleeds
• Headache
• Pain in the face
• Difficulties in opening mouth
• Blurred or double vision

Who should go for NPC screening?

According to the Ministry of Health Singapore Cancer Screening Guidelines, patients with two or more relatives or family members with NPC should go for an NPC screening consisting of EBV serology and nasoendoscopy.

However, if you have symptoms suggestive of NPC, your doctor may also recommend that you undergo a NPC screening. A person with a first degree relative with NPC is more than 20 times more likely to get NPC.

How do I get screened for NPC?

If you have risk factors for NPC, your General Practitioner may first perform a screening blood test. This test is called an EBV serology (from a blood test), looking at your body’s antibody response to EBV. Depending on the level of you EBV serology, your doctor may refer you to an ENT Specialist to undergo a nasoendoscopy (which is a scope through the nose under local anaesthesia).

How is NPC diagnosed?

NPC is diagnosed by a biopsy of the tumour in the nasopharynx. This is done through the nose under local anaesthesia in the clinic. It involves visualising the tumour with a nasoendoscope and removing a small piece of tissue from the tumour. The tissue taken is sent to the laboratory to be prepared, stained and examined by a doctor trained in analyzing tissue for cancer.

If there are lumps in the neck, a fine needle aspiration and cytology (FNAC) may be performed. This involves extraction of some cells from the lump using a small needle in the clinic. These cells are then sent to the laboratory for analysis.

If the biopsy or FNAC confirms the presence of NPC, staging investigations will be ordered. Staging investigations include an  MRI (Magnetic Resonance Imaging) or a CT scan to determine how extensive the cancer is or if it has spread to other parts of the body.

What is the treatment of NPC?

The treatment of NPC depends on the stage of the cancer. Early stage NPC is treated by radiotherapy while advanced stage NPC is treated by a combination of radiotherapy and chemotherapy. Surgery for NPC is usually reserved for cancer recurrence.