Pharmacyclics drug helps find brain cancer-study

By Bill Berkrot

NEW YORK, June 3 (Reuters) - Pharmacyclics Inc.'s (PCYC.O: Quote, Profile, Research, Stock Buzz) experimental drug Xcytrin showed promise in helping improve the effectiveness of radiosurgery treatment and in detecting hard to find cancerous brain lesions in a mid-stage clinical trial, researchers said on Sunday.

Final data from the study of the drug, known chemically as motexafin gadolinium, were presented at the American Society of Clinical Oncology annual meeting in Chicago.

In the mid-stage clinical trial, Xcytrin allowed physicians to identify occult brain metastases -- previously undetected cancer that has spread to the brain -- in 24 percent of patients whose lesions were missed using standard MRI contrast agents and were candidates for stereotactic radiosurgery, researchers said.

"This study demonstrates that Xcytrin may be used both to enhance the effectiveness of radiation and to improve detection of occult lesions in patients with brain metastases," said Dr Minesh Mehta, professor of Human Oncology and Neurological Surgery at the University of Wisconsin Medical School who presented the study at the year's most important cancer meeting.

"It appears that a significant number of patients are being under-treated since current imaging and stereotactic radiosurgery techniques fail to identify and treat all the tumors," Mehta said.

The gadolinium part of the molecule is a metal with paramagnetic properties that enable it to show up on MRI scans with more sensitivity than standard imaging agents, Mehta explained.

He said patients eligible for radiosurgery usually have just a few lesions.

"We give them radiosurgery in order to try to control the disease for a longer period of time in the brain and hopefully have them live longer and have better neurologic quality of life," Mehta said.