Tongue Squamous Cell Carcinoma (TSCC) is the most common malignancy affecting the tongue, typically originating in the flat, thin cells that line its surfaces. This cancer is classified as a type of oral or oropharyngeal cancer, depending on the location of the tumor. Cancers of the oral tongue occur in the front two-thirds of the organ, while those at the base of the tongue are considered oropharyngeal cancers. Early detection is important because, like other head and neck cancers, its prognosis is strongly linked to how far the disease has progressed at the time of diagnosis.
Identifying the Primary Risk Factors
The vast majority of tongue cancer cases are strongly linked to preventable lifestyle factors, with tobacco use being the most significant contributor. This includes both smoked products, such as cigarettes and cigars, and smokeless forms like chewing tobacco. The carcinogens present in tobacco directly damage the DNA of the tongue’s cells, promoting cancerous changes over time.
Heavy alcohol consumption is another significant risk factor for developing TSCC. The risk dramatically increases when alcohol and tobacco are used together, creating a powerful synergistic effect. Alcohol is thought to act as a solvent, increasing the permeability of the oral lining and allowing tobacco carcinogens to penetrate the tissues more easily.
A growing number of tongue cancers, particularly those at the base of the tongue, are associated with the Human Papillomavirus (HPV), specifically the high-risk strain HPV-16. This association is independent of tobacco and alcohol use and often affects younger patients without typical lifestyle risk factors. Other contributing factors include chronic irritation, such as that caused by sharp, broken teeth or ill-fitting dentures that constantly rub against the mucosal lining. Poor oral hygiene also increases risk by fostering chronic inflammation and making the oral tissues more vulnerable to carcinogens.
Recognizing the Early Signs
Early detection relies on recognizing changes that persist beyond a typical healing period, generally two weeks. The most common initial sign of oral tongue cancer is a non-healing sore or ulcer. Unlike a common canker sore, a cancerous ulcer often appears as a grayish-pink lesion with a hard, raised, or rolled border, and may bleed easily when touched.
Precancerous conditions may also appear, such as Leukoplakia, which presents as a thickened, white or gray patch that cannot be scraped away. Erythroplakia is a less common but high-risk red patch. Persistent pain, tenderness, or a burning sensation on the tongue that cannot be explained by other causes should also raise suspicion. As the tumor grows, it can invade nerves, leading to unexplained numbness or a loss of sensation in parts of the tongue or mouth.
Symptoms differ for base of tongue cancers. These tumors often manifest as a persistent sore throat or the feeling that something is constantly caught in the throat, known as globus sensation. Patients may also notice a lump in the neck, which is often the first sign of the disease having spread to the regional lymph nodes. Difficulty or pain when swallowing is another symptom that suggests a tumor is growing in the posterior part of the tongue.
Diagnostic Procedures and Staging
The diagnostic process begins with a thorough physical examination, where a healthcare professional visually inspects the oral cavity and uses gloved fingers to palpate the tongue and neck for lumps or areas of induration. A definitive diagnosis of TSCC requires a biopsy, which involves collecting a tissue sample for microscopic analysis by a pathologist.
Once the cancer is confirmed, imaging tests are used to determine the extent of the disease, known as staging. Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) scans help measure the tumor’s size and its depth of invasion into surrounding structures. PET/CT scans identify areas of increased metabolic activity, which helps detect cancer spread to distant sites or to lymph nodes that may appear normal on other scans.
The TNM system is the standard classification method, where T stands for the size and extent of the primary Tumor, N describes the involvement of regional lymph nodes, and M indicates the presence of distant Metastasis. This classification guides treatment planning and provides an indication of prognosis. For example, a T1N0M0 classification represents a small, localized tumor with no spread, suggesting a highly curable early-stage cancer.
Overview of Treatment Pathways
Treatment for tongue cancer depends primarily on the cancer’s stage, location, and the patient’s overall health. Surgery is the primary treatment for most oral tongue cancers, especially those in the early stages (T1 and T2). The procedure involves a glossectomy, which removes the cancerous section of the tongue.
Surgical intervention often includes a neck dissection, where lymph nodes in the neck are removed, even if they appear normal on imaging. For more advanced tumors (T3 and T4) or those with confirmed nodal involvement, surgery is typically followed by adjuvant therapy. This treatment involves radiation therapy, or chemoradiation, which combines radiation with chemotherapy to eliminate any remaining cancer cells and reduce the risk of recurrence.
For some base of tongue cancers, and for patients who are not suitable surgical candidates, chemoradiation can be used as the primary treatment. Rehabilitation is essential for recovery, particularly for speech and swallowing functions. Speech and language pathologists work with patients to perform exercises that maintain the range of motion in the tongue and jaw, helping to improve communication and reduce the risk of long-term swallowing difficulties.