Mayor Bob O'Connor received his first treatment of whole-brain radiation yesterday -- several days earlier than expected -- and will have another today because of "worsening symptoms" of his rare brain cancer, according to his doctors.

		Related article Mayor's illness prompting outpouring of get-well wishes

In a prepared statement, Mr. O'Connor's medical team said his symptoms "included headache and increased lethargy," and were thought to be the result of fluid buildup overnight Wednesday.

The mayor was diagnosed last month with primary central nervous system T-cell lymphoma.

The fluid increase meant it wasn't possible to do surgery, planned for yesterday, to internalize a shunt that would channel excess fluid from the brain into the abdomen. Instead, the external drain has been adjusted to accommodate the increased fluid level.

Because of the symptoms and postponement of the shunt procedure, the medical team decided to begin radiation of Mr. O'Connor's entire brain yesterday. The treatment took about 10 minutes. He is expected to have another treatment today, plus intensity-modulated radiation therapy, or IMRT, on Monday.

Last week, doctors said bleeding from the brain tumors apparently led to a fluid buildup and the need for a shunt. At a press briefing two days ago, they indicated the bleeding had resolved.

Dr. Michael Robertson, director of the lymphoma program at the Indiana University Cancer Center in Indianapolis, said he was unsure why the mayor's fluid level might have increased. Most patients with primary central nervous system lymphoma don't have that kind of fluid buildup, he said.

Dr. Robertson, who has no direct knowledge of the mayor's condition or treatment, said it was difficult to say whether the latest fluid buildup is a negative development.

"I think this is another instance where we'll have to wait and see," he said.

The radiation therapy the mayor is getting will target four brain tumors that did not respond to three rounds of high-dose methotrexate chemotherapy.

At Wednesday's briefing, UPMC Hillman Cancer Center neuro-oncologist Dr. Frank Lieberman said, "At this point, the tumors, which are not shrinking, are causing neurologic problems. In order to improve his level of function, we're going to have to get rid of those lymphoma masses. That's what this radiation therapy is designed to do."

He added, "If the mayor responds to therapy, he's going to improve neurologically and for a substantial period of time."