"New Cancer Therapy Gets FDA Go-Ahead
Cells made light-sensitive, zapped"

Washington (Associated Press)
Patients who choke on cancerous throat tumors may get help from a new therapy approved by the government yesterday that destroys tumor cellswith light.

The Food and Drug Administration approved the treatment, known as Photofrin, to help clear the esophagus when tumors grow so big that patients cannot swallow.

The FDA action makes Photofrin the first of a new type of cancer treatment called photodynamic therapy, in which patients are given a drug to make their tumors light-sensitive. The light then kills the cancer cells. Such therapies also are being tested against bladder, bronchial and other tumors.

The American Cancer Society estimates that 12,100 Americans developed esophageal cancer this year and that 10,900 of them died, their throats slowly constricted until they could not eat or even swallow their own saliva.

The standard therapy is to chip away at the tumor with a laser. But some patients have tumors that cannot be removed surgically and are too big for the laser to reduce.

Photofrin, made by QLT Phototherapeutics Inc. of Canada, is a chemically modified version of a substance called porfimer sodium that is culled from pig's blood. Patients are injected with Photofrin. Several hours later doctors thread fiber-optic cables into the esophagus and shine bright light onto the tumor. The light activates the Photofrin, making it produce substances called free radicals that kill cells. A drawback of the treatment is that patients remain vulnerable to very severe sunburn until the drug wears off in about 30 days.

Thursday, December 28, 1995
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