Radiation Therapy for Head and Neck Cancers

Radiation therapy plays an important role in the management of head and neck cancers. Radiation is often given as the only treatment – as definitive treatment – with curative intent. This may be possible for some early stage tumors in certain areas. Sometimes radiation therapy is given with chemotherapy since they may work in synergy and increase chance of tumor control. Your cancer physicians can best guide you as to the best treatment plan – tailored to your situation.

One of the big advantages of radiotherapy in the management of head and neck cancers is that mutilating surgery can sometimes be avoided – surgery in such a sensitive area as the face, head and neck can cause physical disfigurement compromising a persons well being, self esteem and social interactions.

In certain situations, surgery for management of a head and neck tumor may be unavoidable, due to disease extent. Radiation therapy is sometimes given after surgery to improve chances of cure, since very often, microscopic disease may be left behind after the operation.

Diagnosis and Treatment Options

The stage of the cancer is important, and is rated from I to IV. Staging is the determination of tumor extent – how large the tumor is and if it has spread.

Depending on the stage, recommendations regarding treatment can be made. Staging involves a careful physical exam by the physician, and use of imaging studies such as CT scan, MRI, and PET scanning.

Radiation treatment to the head and neck area is given for a variety of malignant conditions. These treatments typically last for a total of 5 to 8 weeks and may be administered once per day or twice per day five days per week. Usually a custom mask is made to stablize the head, so as to avoid movement, so the same area is treated accurately each day (Image B).

We are entering an exciting era in the treatment of head and neck cancer – on many fronts. One of the exciting areas we are now witnessing is the fusion of imaging, radiation and treatment planning technologies. Such fusion allows one to determine the precise location of the tumor for radiation treatment planning.

Image C shows how the marriage of detailed imaging with radiation treatment planning has helped to more effectively target tumors with greater accuracy. In this case it is a PET scan fused with a CT scan.

The technology to target the radiation beam to the tumor is now much greater with the advent of IMRT (intensity modulated radiation therapy) (see D and E). The technique results in less “collateral damage” from radiation therapy – and less dose to the normal tissues means less side effects. Moreover with IGRT (image guided radiation therapy) we can now image the tumor before each treatment to ensure accuracy of the treatment even more.

Cancers of the Head & Neck - Radiation Therapy Side Effects

As with any medical procedure, there can be side effects from treatment. The side effects from radiation therapy depend on the site that is being irradiated.

Skin reaction usually occurs within the treated area with concomitant loss of treated facial hair. The reaction may resemble a sunburn which typically reaches its maximum during the final week of treatment as well as the first week after treatment, after which it usually subsides fairly rapidly. There are a variety of topical measures used to alleviate this condition.

If any salivary tissue is in the path of the beam, there will usually be moderate to severe dryness of the mouth and altered taste. These problems usually appear within 1 to 3 weeks after starting radiation therapy. The taste typically returns gradually over a period of several months after completion of the radiotherapy. Salivary function may or may not return over a period of six months to several years after radiation therapy.

The most severe side effect of head and neck radiation therapy for most patients is soreness inside the part of the mouth or throat which is being treated, combined with increased production of phlegm and/or mucous. The problem starts after about two weeks of treatment and increases in intensity until the treatment series is completed. It resolves over a period of 1 to 8 weeks following the radiation therapy.

Because of the loss of taste, dry mouth and soreness of the membranes which accompany head and neck radiotherapy, many patients will lose a significant amount of weight under treatment. Your physician and staff will work with you to try to minimize this effect through dietary advice and symptomatic medical management. In severe cases, more aggressive dietary support may be needed including measures such as placement of a small flexible feeding tube directly into the gastrointestinal tract, bypassing the irritated segment.

Dental care is extremely important in head and neck cancer patients such that they are referred to the dentist before radiation therapy is started for appropriate cleaning, dental restoration and occasionally, extraction of diseased teeth. Customized dental trays are also made for the purpose of placing a fluoride gel to be applied to the teeth to decrease the risk of dental decay.

The risk of severe injury to the jaw bone is less than 5% with appropriate attention to dental care. Rarely, catastrophic or fatal injuries may affect other normal tissues such as brain, sensory system, vision, hearing, spinal cord, blood vessels, or skin. Fortunately, these are very unusual complications.