Labor frontbencher Brendan O'Connor is taking leave from federal parliament to spend time with his ill wife and family.
Jodi Dack was diagnosed with breast cancer in 2012 and, despite going through invasive treatment, it returned two years later.
Mr O'Connor told parliament on Tuesday the couple received more bad news this month and another round of intensive medical treatment is needed.
"While I'll continue to work on portfolio and constituent matters, I need to be close to home to be there for my family for the next month," he said, fighting back tears.
He thanked his staff and caucus colleagues for helping him during this time and all the well wishers.
"Jodi and I have every intention of seeing off this most recent challenge and getting on with living a rich and purposeful life," he said.