Nutritional Implications of Dental and Swallowing Issues in Head and Neck Cancer
Nutritional Implications of Dental and Swallowing Issues in Head and Neck Cancer
Worldwide, a half million new cases of head and neck cancer arise
each year. In the United States, head and neck tumors account for
approximately 4% of the overall incidence of cancer, and represented
approximately 30,750 new cases in 1997.
Cancers of the mouth, larynx, pharynx, tongue, and salivary glands
have an enormous impact on eating and swallowing. The location or
progression of the tumor itself causes various dental, swallowing,
and nutritional consequences, as do such treatments as surgery,
radiation, and chemotherapy. Moreover, common side effects of cancer
treatment, such as xerostomia, mucositis, dental caries, taste
alterations, and dysphagia, may give rise to secondary malnutrition.
Strategies for the prevention and alleviation of such problems
include dental, swallowing, and nutritional therapies. Therefore,
optimal patient care requires a multidisciplinary approach involving
dental, speech, and nutritional professionals.
This article discusses therapies used in managing dental and
swallowing problems experienced by head and neck cancer patients. In
addition, it provides guidelines for integrating dental, swallowing,
and nutritional interventions into overall patient management both
before cancer treatment is initiated (Table
1) and during and after treatment (Table
2). This paper also aims to expand health professionals
knowledge of dental and swallowing therapies in the head and neck
cancer patient population.
Over half of patients with head and neck cancer are
malnourished.[2,3] Their nutritional status is often compromised even
before the diagnosis of cancer is made and treatment is initiated.
Weight loss and dysphagia are early signs of head and neck cancer,
often prompting the patient to seek medical attention.
Early screening and assessment help determine the degree of
malnutrition present and which nutritional intervention is needed.
The assessment should include information on acute and chronic weight
loss, current laboratory data, and clinical observation. A history of
patients dietary intake, both at home and during
hospitalization, provides an estimate of the adequacy of calorie,
protein, and fluid intake. The degree of feeding impairment and
swallowing difficulties anticipated during and after treatment also
should be estimated so as to make recommendations about oral,
enteral, and parenteral therapies that may be necessary.
Treatment of the head and neck cancer patient is unique in that the
procedures and therapies used (ie, surgery, radiation, and
chemotherapy) may have a direct effect on the oral structures and,
therefore, can impair chewing, swallowing ability, and nutritional
status. Nutritional intervention should be an integral part of
pretreatment and posttreatment patient care, as it may improve
patient prognosis and decrease the likelihood of secondary malnutrition.
Typical nutritional interventions provided include various strategies
to overcome the side effects of cancer treatment (Table
3). For example, increasing fluid intake helps relieve
xerostomia. Patients who are underweight or losing weight may need to
eat more frequently; also, oral nutritional supplements can help
patients maintain adequate calorie and protein intake. Nutritional
support, including enteral and parenteral routes, may be indicated
for patients who cannot meet their nutritional needs by mouth. Also,
if dysphagia is present, modification of food textures and
consistencies may be required.
Since nutritional risks are high in head and neck cancer patients,
nutritional therapy is a critical part of their care. In addition to
the factors that contribute to malnutrition in all cancer patients,
dental and swallowing problems are of special concern in head and
neck cancer patients. In order to formulate an appropriate
nutritional care plan for these patients, consideration should be
given to dental and swallowing problems that may be contributing to
declining nutritional status.
Dental treatment and oral health are essential for the comprehensive
care of head and neck cancer patients. The dentist and dental
hygienist can help the patient with oral and dental problems and
assist in instituting preventive measures. All patients need
pretreatment and posttreatment education to decrease the risk of
dental caries. They also need special instruction on oral hygiene
(ie, brushing, flossing, rinses, and other plaque removal devices).
Therefore, early dental referral is necessary. Improved oral health
can have a beneficial impact on chewing and swallowing ability.
In particular, a dental consultation should be initiated before
radiation therapy in head and neck cancer patients. Even patients
with excellent oral health need to be informed of the dental risks of
radiation (see below), especially if they do not use fluoride daily.
Problems Secondary to Radiation and Chemotherapy
Many oral problems result from radiation therapy. If left untreated,
these radiation-induced problems can have a negative effect on
patient outcome and recovery. Acute reactions associated with
radiation therapy to the head and neck usually occur 10 to 17 days
into treatment but can begin as early as the first week. These
reactions, which include dental caries, xerostomia, oral mucositis,
and bacterial and fungal infections, are a result of damage to the
salivary glands (parotid, sublingual, and submandibular glands) and
the consequent reduction in saliva production.
The effects of chemotherapy are similar to those of radiation
treatment. Problems that may occur include mucositis, fungal
infections, xerostomia, throat and mouth pain, taste changes, food
aversions, nausea, and diarrhea. The kind of side effects that a
person may experience depend on the kind of chemotherapy drugs used,
as well as the dose and frequency of the treatments. Some side
effects can be prevented (eg antinausea medications) or at least
effectively managed (see Table 3 and
Functionally, saliva balances the microbial flora in the mouth and
maintains an appropriate acid-base medium. Saliva lubricates the
mouth and aids in chewing, swallowing, and digesting food. In
addition, saliva provides substances with antibacterial, antifungal,
and antiviral activity, and protects the oral mucosa against physical
and thermal trauma, toxins, and chemicals.[5,6] Salivary proteins
help maintain a balance of calcium and phosphate ions, which aid in
Table 4 summarizes the treatments
available for oral complications of radiation and chemotherapy. These
treatments can alleviate pain and ease eating and swallowing. Dental
therapy for various side effects of radiation and chemotherapy
includes prescription of fluoride application, saliva-stimulating
medications, and antifungal and antibacterial agents, as well as
frequent dental cleanings.
Prevention/Treatment of Radiation Caries--Radiation caries is
a major problem in patients undergoing radiation therapy to the head
and neck. The effectiveness of topical fluoride treatment in halting
radiation caries has been examined in head and neck cancer patients.
Most patients treated with fluoride maintained good dental status
while following the treatment regime, which included use of a
fluoride gel in a custom-made tray. However, if patients
discontinued fluoride treatment, caries occurred after 3 to 6
months. In addition to decay prevention, fluoride gel can minimize
The daily use of fluoride is therefore critical in patients
undergoing radiation therapy. A custom-made mouth tray should be
fabricated by a dentist prior to radiation therapy. Instructions on
fluoride application (Table 5)
should be given in both written and verbal forms.
Prevention of dental caries also includes counseling on avoiding
foods high in sugar. Sometimes, in patients who cannot tolerate fat,
high-sugar foods and liquids may be recommended to increase caloric
intake. In order to decrease dental risks, it is critical that these
patients be advised to brush and floss immediately after eating.
Treatment of xerostomia is also critical in the management of
head and neck cancer patients. Sugar-free mints and gum can be used
to help stimulate saliva. Artificial saliva is also effective in
relieving xerostomia; however, one study indicated that water can
also help the mouth stay lubricated. In addition, cost was
identified as a deterrent to the use of saliva substitutes.
Another method of treating xerostomia is to induce salivary flow
medically. Pilocarpine hydrocloride (Salagen) stimulates the cells of
the salivary glands that are not totally damaged by radiation. Side
effects of pilocarpine hydrochloride include sweating, headache,
rhinitis, dizziness, and urinary frequency.
Treatment of Mucositis--Mucositis can be treated in a variety
of ways. These include topical anesthetics, diphenhydramine solution,
water, saline, or sodium bicarbonate solution. Vitamin E capsules
can lubricate the oral mucosa and are highly acceptable to patients
due to their lack of toxic effects. In one study of patients with
chemotherapy-induced mucositis, topical application of vitamin E was
effective in healing the mucosa. Whether the effects of vitamin E
are due to some action of the vitamin or simply to increased
lubrication remains to be determined.
Preliminary studies of capsaicin (the active ingredient in chili
peppers) showed that a capsaicin-containing candy provided some
relief of oral mucositis. Also, a calcium phosphate rinse is
being used to alleviate mucositis in some institutions; however,
there are limited data on its effectiveness.
Alcohol-containing mouth rinses dry the oral mucosa and are
contraindicated in patients with mucositis. Hydrogen peroxide
solutions should also be avoided because of their ability to break
down new tissue. A soft diet may be recommended for patients with
mucositis, to prevent further tissue irritation.
Long-Term Oral Side Effects--Long-term oral side effects
associated with radiation therapy include osteoradionecrosis and
trismus. In patients with osteoradionecrosis, bone death occurs
primarily because of vascular insufficiency to the area. This
condition can be very painful for patients and sometimes results in
eventual loss of portions of the maxilla or mandible.
Osteoradionecrosis tends to occur in persons who have chronic,
advanced periodontal disease.
If osteoradionecrosis does occur, treatment involves gentle
debridement with salt and soda rinses, antibiotics, and hyperbaric
oxygen therapy.  Hyperbaric oxygen therapy is used to prevent the
initiation of bone necrosis and to prevent its further progression.
It is generally accepted that a patient with bone exposure that
persists for longer than 6 months without any improvement would be a
candidate for hyperbaric oxygen therapy.]
Trismus (fibrosis of oral muscles) makes chewing foods difficult. It
can be minimized or eliminated with appropriate jaw exercises.