Oral Cancer

Oral cancer, also known as mouth cancer, is a malignancy that affects the lining of the lips, mouth, or upper throat. It often starts as a painless white patch that thickens, develops red patches, ulcerates, and continues to grow.

When on the lips, it may manifest as a persistent crusting ulcer. Other symptoms can include difficulty swallowing, lumps in the neck, swelling in the mouth, or numbness in the mouth or lips.

Oral cancer on the side of the tongue, a common site along with the floor of the mouth

Risk Factors

Key risk factors for oral cancer include tobacco and alcohol use, with a significantly heightened risk for those who use both. Other contributing factors include HPV infection, chewing paan, and sun exposure on the lower lip.

Tobacco

Tobacco use, whether smoked or chewed, is the single greatest cause of oral and pharyngeal cancer. It increases the risk by 3 to 6 times and accounts for around 40% of all oral cancers.

Alcohol

Alcohol consumption is another major cause, responsible for 20% of global cases in 2020. The risk increases with the amount and frequency of alcohol use, especially in combination with tobacco.

Human Papillomavirus (HPV)

HPV, particularly type 16, is a significant risk factor, notably for cancers of the tonsil, base of the tongue, and oropharynx. HPV-positive oral cancers tend to affect younger individuals and respond better to radiotherapy than HPV-negative cancers.

Betel Nut

Chewing betel quid (paan) and Areca nut products doubles the risk of oral cancer and is particularly prevalent in regions like India, where oral cancer represents a significant proportion of all cancer cases.

Stall selling betel quid

Signs and Symptoms

Signs of oral cancer vary with location but often include thin, irregular white patches or a mix of red and white patches. Common symptoms are persistent ulceration with a raised border, crusting ulcers on the lips, and masses in the pharynx. Additional signs may include loose teeth, bleeding gums, persistent earache, numbness in the lip and chin, and swelling.

Swelling of the right neck from the spread of oral cancer

Ulceration on the left lower lip caused by cancer

Diagnosis

Diagnosis involves a biopsy of the suspicious area followed by imaging techniques like CT, MRI, and PET scans to assess the spread of the cancer. Panendoscopy may be recommended due to the common occurrence of multiple primary cancers in the upper aerodigestive tract.

A large squamous cell carcinoma of the tongue as seen on CT imaging

Histopathologic appearance of a poorly differentiated squamous cell carcinoma specimen

Treatment

Treatment options include surgery, radiation therapy, and chemotherapy, often used in combination depending on the cancer's size, location, and spread.

Surgery

Most oral cancers are treated surgically, often requiring the removal of part of the jaw if the tumour involves the bone. Neck dissection is very important when lymph nodes are involved to improve survival rates.

Common scar line after cervical lymph node dissection

Radiotherapy and Chemotherapy

Radiotherapy is used either alone for small lesions or in conjunction with surgery for larger or more extensive cancers. Chemotherapy is generally used as an adjunct to surgery and radiation, not as a standalone treatment.

Radiation treatment

Prognosis

Survival rates for oral cancer depend on the stage at diagnosis and the specific site of the cancer. Early-stage cancers have a five-year survival rate of approximately 90%, while advanced cancers have significantly lower survival rates.

Epidemiology

In 2018, there were about 355,000 new cases of oral cancer globally and 177,000 deaths. The incidence is higher in males and varies significantly across different regions, with higher rates in lower and middle-income countries.

Deaths from mouth and oropharynx cancers per million people in 2012