Sworn in as a new MP just 15 days ago,she received the"unexpected news"last week that her cancer had returned.
"While this has come as a shock,my doctor advises me that my condition is treatable and that he expects me to do well with treatment,which I will start in the coming weeks,"Ms Murphy toldThe Sydney Morning Herald and The Age.
"I have terrific support from family,friends and colleagues,and a strong fighting spirit."
It was her first cancer fight which gave the former barrister the courage to stand for Parliament at the last two elections.
Ms Murphy has spoken openly in the past about how her initial diagnosis had prompted her to enter politics after a previous career as a justice policy advisor to Labor minister and now Federal Court judge Duncan Kerr.
She was first diagnosed with cancerous tumour in her breast in 2011 while acting as a junior counsel in a murder trial.
Ms Murphy and her husband,public sector consultant Rod Glover,moved to Mt Eliza to be closer to family,before a short stint in the United States where she completed her recovery following surgery and intense chemotherapy.