Dr Raymond NG Wai Man

Cancer is the generic name given to a cluster of related diseases. In a normal healthy body, human cells grow and divide as the body needs them. When cells become old or damaged, they die and new cells take their place. However, cancer relates to body cells dividing uncontrollably and spreading to neighbouring tissues.

Head and neck cancer is a collective term for cancers that occur in various upper respiratory tract tissues. Depending on the site of occurrence, it can be divided into oral cancer, nasopharyngeal cancer, oropharyngeal cancer, hypopharyngeal cancer, and laryngeal cancer. The most common tumour type in head and neck cancer is squamous cell carcinoma, which originates from squamous cells on the mucosal surface of the head and neck. According to medical research, some head and neck cancers are associated with HPV (human papillomavirus).

Nasopharyngeal cancer is one of the top ten cancers in Hong Kong that cannot be ignored. There are 600 to 800 cases of nasopharyngeal cancer in the city every year. Unlike many other cancers, nasopharyngeal cancer tends to occur at a relatively early age, with the peak incidence between 40 and 60 years old, considered the prime of one's life. The incidence rate is almost three times higher in males than in females. Compared to Western countries, nasopharyngeal cancer is more commonly found in Southern China.

The "oral" region comprises multiple sites, including the lips, tongue, floor of the mouth, hard palate, and gums, as well as the oral mucosa, buccal mucosa, and salivary glands. Any malignant tumour growing in these locations is collectively referred to as oral cancer, which is also one of the types of head and neck cancer.

Skin cancer is a common cancer in Hong Kong; non-melanoma skin cancers account for 90% of all skin cancers. Though the incidence rate in Hong Kong is much lower than in the West, the number of local new cases due to non-melanoma skin cancer has significantly jumped by 20% from 2010 to 2020.

The throat means the muscular tube behind the nose and neck. Throat cancer (or pharyngeal cancer) broadly refers to the growth of flat cells in this area.

In 2020, there were a total of 978 new cases of thyroid cancer, accounting for 2.9% of all new cancer cases in Hong Kong and ranking tenth among common cancers. The incidence rate per 100,000 population is approximately 13 cases. Thyroid cancer patients are typically middle-aged to elderly, with papillary thyroid cancer occurring in younger people and rare in children. Additionally, the risk of thyroid cancer is higher in females, with a rate approximately 3.8 times that of males.