Photodynamic therapy (PDT) relieves swallowing
problems associated with esophageal cancer in the majority of
patients treated, according to a study conducted from November 1996
to June 1998 at the University of Pittsburgh Cancer Institute. The
study, which was presented at the 1999 meeting of the Society of
American Gastrointestinal Endoscopic Surgeons in San Antonio,
involved 77 patients with either primary esophageal cancer or a
recurrence of disease after other treatments failed. All patients
were treated with PDT.
Although further studies will need to be done in this area, we
found PDT to be effective in our patients, said James D.
Luketich, MD, senior coauthor of the study and assistant professor of
surgery at the University of Pittsburgh. This is one of the
first reports, after FDA approval of PDT, that shows that it is
effective in relieving swallowing problems in patients with
esophageal cancer, he said. Ninh T. Nguyen, MD, currently of
the University of California at Davis and formerly with the
University of Pittsburgh Medical Center, coauthored the study.
How PDT Works
During PDT, surgeons administer an injection of porfimer sodium
(Photofrin). The drug remains dormant until it is activated by a
nonthermal red laser light positioned at the end of a thin,
fiberoptic probe. The doctor inserts this line into the patients
esophagus and targets the cancer cells. Once in place, the laser
light activates the drug, destroying the cancer cells and leaving the
surrounding healthy tissue largely unharmed.
For the study, doctors administered 1.5 to 2 mg/kg of porfimer sodium
intravenously, followed 48 hours later by the laser light treatment.
Endoscopy was performed 2 days after the initial treatment to assess
tumor response and debridement and to determine whether a second
light treatment would be necessary. The study measured the degree of
palliation by the dysphagia-free interval and through the use of a
dysphagia score of 1 to 5 (where 1 represents no dysphagia and 5,
All of the patients were treated with 125 courses of PDT, of which 87
were for obstruction, 6 for bleeding, and 32 for tumor ingrowth or
overgrowth (the result of previously placed esophageal stents).
Dysphagia Scores Decline
Dysphagia scores improved in 90% of the patients following 4 weeks of
PDT. The mean dysphagia score decreased from 3.2 preoperatively to
1.9 postoperatively, and PDT adequately controlled bleeding in the
six patients treated. The mean dysphagia-free interval was 75 days,
with a median survival time of 5 months. A second course of PDT was
required in 38% of the patients, and an expandable metal stent was
placed in 29% when tumor progression resulted in extrinsic compression.
According to Dr. Luketich, expandable metal stents typically have
been used in patients with esophageal cancer and continue to play an
important role in some patients. However, in some cases, stents may
have significant disadvantages. These include tumor ingrowth and
stent migration. Also, in some patients, severe esophageal reflux
disease and pain can limit the effectiveness of the expandable metal stent.
For more information on the use of PDT as a treatment for lung or
esophageal cancer, contact the University of Pittsburgh Cancer
Institutes Cancer Information and Referral Service at either
1-800-237-4PCI (4724) or (412) 624-1115 or visit the institutes
web site at http://www.upci.upmc.edu.