Diagnosis and Treatment of Oral Cancers

Diagnosis and treatment in oral cancers form a process made up of successive steps. It begins with the examination of a suspicious finding and is confirmed with a tissue sample; imaging then shows the extent of the disease, and an individual treatment plan is drawn up in the light of what is found. This page describes, step by step, the common pathway that applies to all cancers of the tongue, floor of the mouth, gum and inner cheek.

Examination and biopsy

The first step is an examination of the mouth by eye and by hand under a good light. The tongue, the area beneath the tongue, the inner cheeks, the gums and the palate are assessed one by one; the neck is examined for palpable lymph nodes (lymph glands). If necessary, the back regions of the mouth and the throat are inspected with a thin camera (endoscope).

The definitive diagnosis is made by taking a small piece of tissue from the suspicious area (biopsy) and examining it under the microscope. This procedure is mostly performed under local anaesthesia and takes a short time. If there is a swelling in the neck, taking a sample of cells with a fine needle (fine-needle aspiration) helps to assess spread.

Imaging and staging

When the biopsy confirms cancer, how deep the disease has gone and where it has spread is investigated:

• Magnetic resonance imaging (MRI): the method that best shows spread within the soft tissue and the depth of the tumour
• Computed tomography (CT): used for jawbone involvement and the neck lymph nodes
• Ultrasonography: a practical tool for assessing the neck lymph nodes
• PET-CT: used in advanced stages or when distant spread is suspected
• Panoramic dental X-ray: useful in tumours related to the gum and jaw

The size of the tumour, lymph node involvement and distant spread are brought together to determine the stage of the disease (stage I–IV). The stage is the most important criterion in deciding which treatment is suitable.

Treatment options

The main treatment for oral cancers is surgery. The tumour is removed together with a safe margin of healthy tissue around it; the edges of the removed tissue are examined by a pathologist to confirm that no cancerous tissue has been left behind.

• Early stage (stage I–II): Limited surgery, mostly performed through the mouth, is usually sufficient. Even when there is no visible involvement in the neck, the neck lymph nodes may be removed as a precaution if there is a risk of spread (neck dissection).
• Advanced stage (stage III–IV): More extensive surgery, neck dissection and reconstruction with tissue taken from another part of the body may be needed. After surgery, radiation therapy (radiotherapy) is given, in some cases together with drug treatment (chemotherapy).
• When surgery is not suitable: Radiotherapy alone or combined with chemotherapy may be used as the main treatment.

The treatment decision is made by discussion in a board (tumour board) in which the surgeon, radiation oncologist, medical oncologist, pathologist and radiologist take part together. The patient’s general health, age and preferences are also part of this decision.

Preserving function

The mouth is the centre of speech, chewing and swallowing. When treatment is planned, preserving these functions matters as much as removing the disease completely. Dental assessment, speech and swallowing therapy and nutritional support are included in the process from the very beginning of treatment.

Follow-up after treatment

Regular follow-up continues after treatment ends. At these visits, which are more frequent in the first years, the mouth and neck are examined and imaging is performed when needed. Giving up smoking and alcohol both reduces the risk of a new cancer developing and supports recovery.