Pennsylvania Sen. Arlen Specter has had a recurrence of the same cancer he was diagnosed with in February 2005, FOX News has learned.

But an early press release obtained by FOX News says the recurrence of Hodgkin's disease, which affects the lymph system, appears to be far less advanced than when it was diagnosed three years ago. Specter is expected to "continue to perform all the duties of his office as well as his activities associated with his candidacy for re-election," according to the release.

"He's fine," a spokesman told FOX News.

Specter, who famously plays squash every morning before starting work, doesn't plan to make any adjustments to his schedule, as he did in 2005.

"I consider this just another bump on the road to a successful recovery from Hodgkin's, from which I've been symptom free for three years," Specter, 78, said in a statement.

Specter finished six months of treatment including chemotherapy from his previous bout with cancer in July 2005.

Specter's statement said the senator "will now receive the Stanford V protocol of chemotherapy weekly over the next 12 weeks."

The statement released by his office said the diagnosis was made based on a routine follow-up scan, which showed small lymph nodes in his chest and abdomen. A follow-up biopsy of one of the chest lymph nodes was positive for recurrence, but the statement said there were no further symptoms.

In his recent book, "Never Give In: Battling Cancer in the Senate," Specter credited hard work with getting him through the cancer treatments.

He's already announced he will run for re-election in 2010, and he said the cancer won't stop him from that.

Specter was bald from his cancer treatments as he was playing a very public role chairing the committee that confirmed John Roberts.

Pennsylvania Sen. Bob Casey released a statement Tuesday saying he was "surprised and sorry" to hear the news about Specter's diagnosis.

"I have no doubt that Arlen will confront his health challenge with the same courage and determination that has marked his previous battles. My thoughts and prayers are with Arlen and his family," he said.

FOX News' Trish Turner and The Associated Press contributed to this report.