Pennsylvania's senior U.S. senator, Republican Arlen Specter, says that working was the best therapy while he was battling cancer - even though he suspects the stress of his job may have caused the disease.

He offers these themes in his new book, Never Give In: Battling Cancer in the Senate (Thomas Dunne Books, $24.95).

So how does the tenacious, squash-playing, 78-year-old workaholic reconcile the conflicting ideas?

"I decided I'm not going to give in to the stress, not giving in to that concern," Specter said during an interview last week at the Union League.

On Feb. 16, 2005, Specter was diagnosed with an advanced stage of Hodgkin's disease, a cancer of the lymphatic system. It came on the heels of a grueling political year in which he won a tough primary race, the general election, and the chairmanship of the Senate Judiciary Committee.

Specter was no stranger to serious illness, having undergone brain surgery for a benign tumor in 1993 and heart bypass surgery in 1998.

Cancer was the scariest of the three "because the risk of death is so high," he said, impeccably dressed in a dark blue suit with a flag pin on the lapel. "I looked at myself in the mirror every day and I saw the deterioration. . . . I didn't recognize myself.

"When you look at mortality, it has a jarring effect on us humans," he asserted.

Yet in his book, written with Frank J. Scaturro, he says "the subject of mortality is one I prefer not to ponder" and "I put thoughts of death out of my mind."

Specter's career in public service has often put him in the midst of stressful controversy. He was assistant counsel to the Warren Commission that investigated President John F. Kennedy's death. He grilled Anita Hill during the Supreme Court confirmation hearing of Clarence Thomas. He criticized his own party for impeaching President Bill Clinton. (Not to mention his efforts this month to resolve a nasty high-stakes dispute between the Philadelphia Housing Authority and the U.S. Department of Housing and Urban Development.)

"People ask me what my legacy will be," Specter writes in his book, "and I respond that it is far too early in my career to give an answer."

In the next paragraph, however, he adds that "I now think of myself as living on borrowed time. . . . All of a sudden, every day is an unexpected day, a bonus."

He ends the book - its title was inspired by a line from Winston Churchill - by offering advice for those facing a health crisis:

"Acknowledge . . . that 'whatever is, is.' "

"Organize and focus on as much of your psychological strength as you can muster to face your medical problems."

"As much as possible, maintain your regular work and exercise schedule."

"Learn as much as you can . . . so that you are equipped to question, even challenge, expert medical professionals."

"Listen to your body."

"Keep busy."