Treatment of Locoregionally Advanced Head and Neck Cancer - An Overview

Introduction

Cancers involving the oral and pharyngeal regions are the most commonly occurring cancers. A locoregionally advanced head and neck cancer is deadly and tends to take the life of patients when left untreated. These cancers are identified by noting the signs and symptoms and taking a detailed patient history. A proper treatment approach is chosen depending on the patient's clinical condition and the cancer stage.

What Is Locoregionally Advanced Head and Neck Cancer?

Head and neck cancers usually involve the head and neck regions, beginning from the cell lining of the mouth, pharynx (throat), or larynx (voice box). Locoregionally advanced head and neck cancer indicates either the presence of larger tumors affecting the lymph nodes or tumors not affecting the lymph nodes or the presence of smaller tumors with the involvement of lymph nodes.

What Are the Stages of Locoregionally Advanced Head and Neck Cancers?

Physicians generally use TNM staging to determine the stage of head and neck cancers.

TNM staging stands for T - tumor, N - nodes, and M - metastasis.

The cancer staging is done based on the location and size of the tumor, involvement of lymph nodes, and spread of the tumor to distant sites.

• Stage I - Tumor is less than 2cm, without spreading to lymph nodes or other body sites (T1, N0, M0).

• Stage II - Tumor less than two to four centimeters, not spreading to lymph nodes or other body sites (T2, N0, M0).

• Stage III - Tumor more than four centimeters, involving the epiglottis, not spread to any lymph nodes or body parts. (T3, N0, M0). Tumor of any size spread to either one node on the affected side or has not spread to any other sites of the body (T1 to T3, N1, M0).

• Stage IV - The tumor is of any size and has spread to lymph nodes and other body sites.

Locoregionally advanced head and neck cancer fall under stage III and stage IV of TNM staging of head and neck cancers.

What Causes Locoregionally Advanced Head and Neck Cancer?

Some of the causes of head and neck cancer include

• Alcohol and tobacco consumption is the most common cause of cancer; they affect the individual's general health and cause cancer in the head and neck region.

• Occupational Exposure - Individuals working in areas like factories or mines get exposed to certain chemicals that cause cancers, like pesticides and asbestos.

• Radiation Exposure - Radiation treatments done in benign and malignant tumors have been associated with salivary gland cancers. However, their risks are low.

What Are the Symptoms Seen in Locoregionally Advanced Head and Neck Cancer?

Some of the symptoms seen in advanced head and neck cancer include -

• Pain.

• Bleeding.

• Weight loss.

• Lumps in the mouth, throat, or neck region.

• Difficulty in swallowing.

• Breathing difficulty.

What Are the Diagnostic Methods for Locoregionally Advanced Head and Neck Cancer?

Several tests help in the diagnosis of locoregionally advanced head and neck cancers. Some of them include

• Biopsy - The doctor removes the abnormal tissues, and a pathologist examines the tissue under a microscope to check for any cancer cells.

• A Positron Emission Tomography (PET) Scan - This diagnostic method creates images of the head and neck region.

• Magnetic Resonance Imaging (MRI) - It is a diagnostic machine that uses a magnetic field to generate images of the internal structures in the body.

• Endoscopy - It is a procedure where a small tube, a light source, and a camera are sent inside the body to view the throat, nasal cavity, voice box, and other areas.

• Laryngoscopy - It is a type of endoscopy where the larynx (sound box) is viewed.

What Are the Various Treatment Options Available for Treating Head and Neck Cancers?

Treatment options for advanced locoregionally advanced head and neck cancer include

• Surgical treatment.

• Non-surgical treatment.

Both treatment approaches aim to reduce the risk of toxicity, increase efficacy, and preserve basic functions. The following are considered while selecting patients for surgical and non-surgical treatments.

Patient Selection in Surgical Treatment Approach -

• Patients with smaller primary tumors.

• Patients with bone involvement.

• Patients contraindicated to radiotherapy.

Patient Selection in Non-surgical Treatment Approach -

• Patients for whom surgery may not provide favorable results.

• Patients who cannot undergo chemoradiation.

What Are the Various Surgical Approaches Involved in the Treatment of Locoregionally Advanced Head and Neck Cancer?

Advanced surgical procedures include -

• Transoral robotic surgery (TORS).

• Transoral laser microsurgery (TLM).

TORS and TLM are minimally invasive endoscopic surgical techniques that manage and allow proper visualization, removal, and identification of primary tumors.

Other surgical approaches to treat advanced neck cancers are based on the extent of the tumor and their response to the primary treatment. They include

• Ipsilateral Neck Treatment - This approach is performed for lesions present laterally, for example, lesions of the tonsils.

• Bilateral Neck Treatment - Lesions located centrally can be treated with this approach, for example, the base of the tongue.

• Selective Neck Treatment - This procedure is done in regions showing the presence of lesions.

What Are the Various Non-surgical Treatment Procedures for Locoregionally Advanced Head and Neck Cancers?

Most of the locoregionally advanced head and neck cancers are treated non-surgically. The non-surgical treatment modalities include

• Radiation Therapy - Usage of a strong dose of radiation to treat cancer.

• Chemotherapy - Using anti-cancer drugs for the treatment of cancer.

• Chemoradiotherapy - A combination of both chemotherapy and radiation therapy is called chemoradiotherapy.

• Adjuvant Therapy is given to all patients who underwent a primary surgical procedure. It is given to maximize and maintain the effect of treatment that has already been given to the patient.

What Are the Complications of Treatment?

• Post - Operative Functional Morbidity indicates the loss of function in a specific organ where the surgery was performed. For example, loss of voice is a post-operative functional issue seen after surgery of the larynx (voice box).

• Xerostomia or dry mouth.

• Osteoradionecrosis is a condition where radiation exposure results in the death of the bone.

What Are the Follow-up Procedures?

Post-treatment follow-ups are necessary to rule out the presence of any remaining disease. After the surgery, follow-ups are recommended every one to three months in the first year, and in the second year, it can be done every four months, in the third year every six months, and once every year after that. Patients must be informed about the chances of recurrence of the cancer and they should also be educated about the symptoms of recurrence.

How to Reduce the Risk of Locoregional Head and Neck Cancer?

The risks of locoregionally advanced head and neck cancers can be reduced by consulting a healthcare practitioner to stop the habit of alcohol and tobacco consumption and avoiding HPV (human papillomavirus) infections by getting vaccinated.

Conclusion

Dentists play an important role in identifying the clinical signs related to cancer in the head and neck regions. The clinical diagnosis is confirmed with the help of diagnostic tests like endoscopy, laryngoscopy, and magnetic resonance imaging. For a positive outcome, choosing the right treatment protocol by an experienced oncologist is essential, along with adequate patient coordination and regular follow-ups after the treatment.