STAR Melbourne forward Jesse Hogan has been diagnosed with testicular cancer.

The 22-year-old will take indefinite leave to give him time to recover after having surgery later on Tuesday to have a tumour removed. 

Hogan is expected to make a full recovery and could return to football within two months, if his recovery goes to plan according to Melbourne doctor Zeeshan Arain.

Arain said the forward would be discharged from hospital as soon as Tuesday, given the surgery is only a day procedure.

"From a physical point of view of the operation and the recovery, we expect somewhere between four and eight weeks," Arain said on Tuesday.

"But we'll have to look back at how he's had an interrupted year from a conditioning point of view, and also his psychological state."

Arain said the early detection of the lump meant surgery was the appropriate course of action, rather than chemotherapy or radiotherapy consistent with other forms of cancer.

The small mass found in his testicle is suggestive of a seminoma, which is a type of cancer

Arain said this form of cancer generally has an excellent prognosis and the swift action that was taken, and the fact the seminoma was in its earliest stage of growth, adds to the positive recovery period.

"He was very lucky," Arain said.

"When they hear that it's an early stage of cancer then their emotions flip around.

"It was really good that Jesse was able to come to us (the doctors) and we were able to follow through."

General manager of football Josh Mahoney said Hogan underwent an ultrasound on Wednesday and was made aware of his cancer diagnosis on Thursday.

"Jesse underwent an ultrasound late last week which revealed a small mass in his testicle suggestive of a seminoma, which is a type of cancer," Mahoney said.

"Jesse has also undergone a CT scan which determined the cancer has not spread to any other part of his body."

Mahoney said in a statement earlier, "The club's collective heart is with Jesse Hogan. This is clearly a very difficult time for Jesse and his health and wellbeing is the number one priority for us. 

"We informed the players of this on Friday and respected Jesse's wishes to keep this information private up until this point."

Hogan was a late withdrawal from the Demons' round eight game against Adelaide and has played just four matches in 2017. 

He recently missed a game after his father Tony died of cancer.

"It's been a really tough year for Jesse and all the things he has gone through," Mahoney said.

"To have news like this has been really difficult.

"What we're seeing is a young 22-year-old mature in front of our eyes.

"The way he was able to handle the death of his father, return to the club and the way he was able to handle himself and play the way he did was a tremendous effort."

Mahoney said the club would continue to support Hogan where it can and said members of the young forward's family would move to Melbourne to be with him during this tough period.

AFL CEO Gill McLachlan said he wanted to pass on the AFL's care and concern for Hogan on behalf of the industry. 

"Our thoughts are with Jesse. We know he is going to have the best care and my understanding is that the diagnosis is positive in the context of bad news," McLachlan said.

"Health and family are pretty much everything and it gives a lot of things a lot of context. He will have all the love and the care that he needs to recover quickly."

Melbourne captain Nathan Jones revealed the players were told the news at Melbourne Airport before their flight to Adelaide last Friday.

Jones said the news about Hogan was used as a motivating factor ahead of the club's 41-point win over Adelaide last Saturday night.

"It was definitely mentioned, particularly when one of our mates is facing some of the things 'Hoges' has faced," Jones said.

"It was an opportunity for us to draw on some of that inspiration, particularly with how he's handled himself and the adversity he's faced. 

"It pales into insignificance the fact that we're playing a game of footy and we've got one of our mates going through the stuff he's been through. 

"Our best way of honouring that was performing on the weekend and making sure we keep a really positive vibe around the footy club and keep supporting him as well as he can."

Hogan joined the Demons in 2013 as a 17-year-old priority selection and played VFL with the Casey Demons for a season until he was eligible to play.

He then missed 2014 with a back injury before making his AFL debut in 2015.

Hogan starred that season, kicking 44 goals in 20 games and winning the NAB AFL Rising Star Award.

He backed up with a solid season in 2016 kicking 41 goals, and overall has played 45 matches and kicked 94 goals.

Key points from media conference

* Last Tuesday, Hogan presented to Dr Zeeshan Arian with a lump. On Wednesday, Hogan had a scan. Last Thursday, Hogan was diagnosed with testicular cancer.

* Hogan will have surgery on Tuesday to remove tumour.

* The outpouring of emotion and support has been unbelievable.

* It was in its early stage of growth. Jesse is expected to make a full recovery and play again this year.

* Josh Mahoney said Hogan is a very resilient character.

* Hogan will be sidelined for four to eight weeks.

* Teammates were told last Friday.

* It’s very different to the type of cancer Jarryd Roughead had.

* Hogan will have some time away from the club, although it’s still to be played out.

* Hogan will spend one day in hospital.