Nasopharyngeal cancer refers to a malignant tumor of the upper aerodigestive tractthat develops in the nasopharynx, a tissue located in the upper part of the throat behind the nose. This is a very rare form ofmalignancy which represents about 3% of head and neck cancers. Nasopharyngeal cancer mainly affects men (80% of cases), and individuals aged 40 years and older.
The pharynx is a tube (cavity) that connects the mouth and nasal passages with the esophagus, a tube that carries food, liquids and saliva from the mouth to the stomach; it plays both respiratory and digestive functions. The nasals designate the nostrils (opening of the nose) and the hollow passage behind the nose; their main roles are to allow breathing and feeling.
Nasopharyngeal Cancer usually begins in the cells of the nasals and pharynx, which is composed of the nasopharynx, oropharynx and the hypopharynx.
Different Types of Nasopharyngeal Cancer
Depending on the tissue affected or the characteristic of the tumor, nasopharyngeal cancer is categorized in four main groups:
- Squamous cell carcinoma (SCC)
- Adenocarcinoma (which affects mostly woodworkers)
- Adenoid cystic carcinoma (AdCC)
- And other very rare types: olfactory neuroblastoma(also called esthesioneuroblastoma), sinonasalundifferentiated carcinoma (frequently referred to by the acronym CNSI), non-Hodgkin lymphoma, melanoma, basal cell carcinoma, soft tissue sarcoma, Ewing’s sarcoma, osteosarcoma, neuroectodermal tumor.
Causes and Risk Factors of Nasopharyngeal Cancer
Although some risk factors for nasopharyngeal cancer are suspected, its development is difficult to trace; it is often considered to be multifactorial. However, people can take steps to prevent exposure to these elements that increase the risk of getting the cancer. For cancer of the nose and pharynx, some common possible risk factors include:
- Wood dust
- Epstein-Barr virus (EBV), also called human herpesvirus 4 (HHV-4)
- Inverted papilloma, benign non-malignant growth of the nasal cavity or paranasal sinuses
- Frequent and repeated exposure to chemicals (textiles, refining of nickel, rubbing alcohol,radium, chromium, formaldehyde)
- Being exposed or affected by any of these risks does not mean that the cancer will occur. This simply means the risk to have it increases. It is, therefore, better to exercise vigilance avoiding them.