Senator John McCain, R-Ariz., will return to the Senate on Tuesday, his office announced on Monday night. McCain, 80, has been home in Arizona following a brain tumor diagnosis.

The announcement of McCain's return comes as Senate Majority Leader Mitch McConnell plans to call a vote Tuesday to begin debate on proposed health care legislation. 

“Senator McCain looks forward to returning to the United States Senate tomorrow to continue working on important legislation, including health care reform, the National Defense Authorization Act, and new sanctions on Russia, Iran and North Korea," his office said in a statement.

With McCain's return - and barring any other absences - there will now be a full compliment of senators on hand for the health care test vote.

That includes 52 Republicans and 48 senators who caucus with the Democrats. Republicans can only lose two votes and have Vice President Pence vote to break the tie and start debate. 

McCain was diagnosed with a brain tumor following a July 14 craniotomy to remove a blood clot from above his left eye, the Mayo Clinic Hospital in Phoenix said last week.

The hospital's examination of the tissue revealed that a primary brain tumor, know as a glioblastoma, was associated with the blood clot.