Throat Cancer

What are the types of throat cancer?

Based on the location, most common types of throat cancers are pharyngeal cancer and laryngeal cancer. On the basis of the type of cells affected, throat cancer may be classified as –

Squamous cell carcinoma – When the cells lining the throat are affected, it is called as squamous cell carcinoma.

Adenocarcinoma – When the glandular cells become cancerous, it is called as adenocarcinoma. Adenocarcinoma of throat is very rare.

What are the risk factors for throat cancer?

Throat cancer is more common in men than women. Poor personal habits increase the chances of throat cancer. Some common risk factors are:

• Age, more common in older people (>45–50 years)
• Alcohol abuse
• Gastroesophageal reflux disease (GERD)
• Habits like tobacco chewing and smoking
• Infection from a sexually transmitted virus called human papillomavirus (HPV)
• Poor dietary habits
• Poor oral hygiene
• Prolonged exposure to harmful chemicals

What are the stages of throat cancer?

Based on the tumor location, involvement in the lymph nodes and spreading, TNM (tumor, node, metastasis) staging of tumor is performed. By staging the throat cancer, your doctor gets a better idea as to –

• Where the tumor is located exactly?
• Is the tumor spreading (also called as tumor metastases), if so, spread to lymph nodes?
• What is the prognosis for the patient – chances of complete recovery and survival?

Staging determines the extent and severity of cancer. The stages range from 0 to 4 based on 3 key pieces of information (TNM):

• The extent of the main tumor (T) i.e its location and effect on the nearby structures
• The spread to nearby lymph nodes (N) i.e spread of the main tumorto nearby lymph nodes, their number and size
• The spread of the main tumorto distant sites or metastasis (M) i.e spread to organs like lungs, liver, or bones

Next, the doctor combines the TNM report and stages throat cancer either as –

Stage 0 – Cancer at this stage is still at the origin of DNA error, usually, in the lining of the throat.

Stage 1 – Stage 1 is an early stage of throat cancer where cancer has not spread to lymph nodes. The tumors are no greater than 2 centimeters.

Stage 2 – Cancer is slowly progressing and tumors are growing in size up to 4 centimeters, however, there is no lymph involvement yet.

Stage 3 – In this stage, the tumor has grown larger than 4 centimeters with or without spreading into the lymph nodes.

Stage 4 – This is the most advanced stage where cancer has spread to major lymph node, or nearby tissues organs, or at least one distant part of the body – such as liver, lungs.

What is the survival rate for throat cancer?

The 5-year survival rate of throat cancer is an estimate of chances of survival for 5 years after being diagnosed with throat cancer. According to American Cancer Society, these values do not provide a complete picture and bear limitations as they are based on data driven from a population with throat cancer. Therefore, survival rates of throat cancer should only be considered as estimates and not be used to predict any consequences for the patient.

• Throat cancer that begins at supraglottis (upper part of larynx) has survival rates of 59%, 59%, 53%, and 34% for stage 1, 2, 3, and 4, respectively.
• Throat cancer that begins at glottis (part of larynx including vocal cords) has survival rates of 90%, 74%, 56%, and 44% for stage 1, 2, 3, and 4, respectively.
• Throat cancer that begins at subglottis (part of larynx below vocal cords) has survival rates of 65%, 56%, 47%, and 32% for stage 1, 2, 3, and 4, respectively.
• Throat cancer that begins at hypopharynx has survival rates of 53%, 39%, 36%, and 24% for stage 1, 2, 3, and 4, respectively.

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