While Sen. Robert Byrd (D-W.Va.) returned to the Senate on Tuesday after a two-month medical absence, Sen. Edward Kennedy (D-Mass.) remained at home and had no plans to come back to the Senate this week.“Sen. Kennedy is at home in Massachusetts and continues to balance his work on health care with his treatment,— spokesman Anthony Coley said in an e-mail.As a veteran player in the health care reform debate, Kennedy, the chairman of the Health, Education, Labor and Pensions Committee, recently penned a lengthy article in Newsweek in which the second-longest-serving Democratic Senator declared overhauling the nation’s health system “the cause of my life.—“For four decades I have carried this cause — from the floor of the United States Senate to every part of this country,— Kennedy, diagnosed in May 2008 with brain cancer, wrote in Newsweek.“Now the issue has more meaning for me — and more urgency — than ever before,— he continued.Kennedy has been receiving treatment for his cancer for more than a year and has largely been absent from the Senate since Inauguration Day, when he was rushed to the emergency room after having a seizure in the Capitol Rotunda. In his absence, Sen. Chris Dodd (D-Conn.) has steered a comprehensive health care bill through the HELP Commitee.