Cancer is a devastating, life-altering disease. As our technology
and knowledge base for the treatment of carcinomas expand, however,
more and more patients' lives are being spared or prolonged. Unfortunately,
the quality of life for many of these patients is diminished--often
due to side effects associated with necessary cancer treatments.
One such consequence of therapy that cancer patients commonly
experience is dry mouth, or xerostomia, resulting from irradiation
damage to the salivary glands. Xerostomia is almost always painful;
is associated with difficulty in speaking, swallowing, chewing,
and sleeping; contributes to severe dental disease and oral infections;
and is usually permanent. Clearly, xerostomia is a chronic disability
for many patients, with physiological as well as psychological
components--both of which can greatly influence the patient's
well-being and must be considered in patient management.
Most clinicians agree that relief of xerostomia has been difficult
to achieve in most patients with currently available treatment
modalities. However, the naturally occurring alkaloid pilocarpine
has shown great promise as a therapeutic agent for xerostomia.
In the articles featured in this supplement, xerostomia and its
consequences for patients are discussed, along with the treatment
of xerostomia with drugs such as pilocarpine. The articles by
Dr. Greenspan and Mr. Iwamoto review the diagnosis and management
of xerostomia, reminding us that subjective discomfort is just
one of the problems that these patients face. We also need to
be concerned about infection and caries, both of which may contribute
to long-term morbidity in these patients.
Dr. Greenspan also describes the findings from several clinical
trials evaluating the efficacy of oral pilocarpine hydrochloride
treatment of xerostomia, including two well-controlled, multicenter,
prospective, clinical trials--one a fixed-dose trial, the other
a dose-titration trial. In both of these pivotal trials, a clinically
significant improvement in dryness was noted in patients treated
with oral pilocarpine hydrochloride. Whole and parotid salivary
flow rates improved as well. The majority of these patients elected
to continue oral pilocarpine hydrochloride treatment at studies'
end via a maintenance trial.
My article summarizes the results of this maintenance study, which
confirmed the findings of the two previous studies--namely, that
dryness improves with pilocarpine hydrochloride therapy. In all
the clinical trials reviewed in this supplement, side effects
associated with this drug were found to be mild and tolerable,
with sweating being the most common. In addition, side effects
usually diminished within hours following cessation of therapy.
In summary, the development of pilocarpine hydrochloride tablets
constitutes an important therapeutic advance in the battle against
xerostomia. Perhaps one of the most compelling reasons for presenting
these data and perceptions, and for continuing with our investigations,
is that it is imperative that we establish a standard of care
for patients with xerostomia, such as those suffering from radiation-induced