John Farnham has been diagnosed with mouth cancer.
He is currently in an intensive care at a Melbourne hospital as he recovers from the nearly 12-hour-long surgery. During the surgery, the tumour was removed, and his jaw has been partially reconstructed.
John's family has thanked everyone for their good wishes.
"There is still a long road of recovery and healing ahead of us, but we know John is up for the task," his wife Jill said.
7NEWS Australia chatted with lead surgeon Linda Monshizade regarding the complications and complexities of John Farnham's recent operation.
"Head and neck surgeries are quite complicated" The lead surgeon Linda Monshizade told 7NEWS Australia
"The surgery itself is quite complex and the reconstruction particularly can take quite a long time" she told.
There are concerns that he may never sing again, but obviously, his overall health is the main concern.
"At the end of the day, the first thing that's going to go through everyone's head including probably John and his family is survival. And ultimately, that's the most important thing" the surgeon said.
"And also trying to optimize his function as much as possible" she added.
Watch the interview below.
Before the surgery, in a statement, the 73-year-old singer said he's thankful that he's able to be treated by the best healthcare professionals in the business.
"Cancer diagnosis is something that so many people face every single day, and countless others have walked this path before me," the statement reads.
"The only thing I know for sure is that we have the best specialist healthcare professionals in Victoria, and we can all be grateful for that. I know I am."
We wish John a speedy recovery and we send him our love and strength!