With a fragile immune system,he could not see the children every day while in hospital for fear of picking up a bug from school.
To avoid dwelling on death or slipping into depression,he focused on the words of his haematologist,Dr Sam Milliken,who was so steady and direct that anything positive stood out.
“Because my haematologist said my prognosis was good,that gave me something to hold on to,” he says. “It gave me something positive in my mind to reinforce positive thoughts.”
Sinodinos jokes now that he took his attitude from the election campaigns he fought with John Howard,as his adviser and chief of staff from 1995 to 2006 and 1987-89.
“During the campaigns I used to cross off every day,once we’d been through it,to get through the 33 days,” he says.
“And with chemo,I was told there’d be a certain number of rounds and I’d be counting the rounds off. There’d be a few unscheduled ones,where they’d want to top me up,but I just worked my way through it.”
One of the lowest points came one year ago when a bad infection turned into septicaemia and he spent the late Sydney summer in the intensive care ward. “I almost died of that,” he says,casually,in the middle of a sentence.
“These are the day-to-day things that happen,that you’ve got to deal with along the way.”
One of the greatest improvements came,slowly,after the bone marrow transplant,which was only possible thanks to a 32-year-old donor in Germany. This has given Sinodinos a strong interest in why Australia does not seem to be as effective as Germany or the US with its bone marrow donation system.
Political friends and colleagues helped to lift his spirits. Turnbull visited. So did Peter Dutton,the Home Affairs Minister. The President of the Senate,Scott Ryan,the Speaker of the House of Representatives,Tony Smith,and Senate colleagues like David Fawcett also kept in touch.
Stephen Brady,an adviser with Sinodinos in the Howard government and later Australia’s ambassador to France,visited him in hospital every day.
“A lot of people,and I’m speaking generically here,find it hard to know what to say sometimes,when you’re dealing with a cancer patient,but I can tell you it’s always good to hear from people so you feel you’re part of the swim of things and you’re not isolated,” he says.
“It’s good for your frame of mind. These days I think I’ve become more sensitive to when people are ill – I’m less reluctant to pick up the phone and ask ‘how are you?’ and talk about what they’re going through and maybe talk about what I’ve been through.”
The one thing to avoid saying,he suggests,is:“You’ll be right.” He was happy for friends to ask:“How do you feel?”
He was there when one friend needed him on the night of Wednesday,August 22. Turnbull called to tell him a leadership spill was on the way and he would need his vote.
“I thought I was in a sufficiently good state I could do it and I knew he wouldn’t call unless he thought I could handle it and it was necessary.”
Sinodinos left at 6am the next morning,with a staff member driving him to avoid the risk of infections from a flight.
On the Friday,after Turnbull had been toppled,he returned to Sydney with an unsentimental view of the outcome,even though the sheer turmoil had surprised him.
“Once it had happened,I guess my attitude was:the party room proposes and the party room disposes,and it has ever been thus. I didn’t dwell on it because,frankly,I had to get back to my daily routine.”
His own political career has not been smooth,including a period when he stepped down as Assistant Treasurer when the Independent Commission Against Corruption called him as a witness in its inquiries into Australian Water Holdings and Liberal Party donations.
There were no findings against him and he rose to cabinet after Turnbull became leader in September 2015,only for the cancer to force him to take leave in September 2017.
Now he returns to Parliament as a backbencher with a desire to engage in issues like innovation,urban congestion and decentralisation,to help the government prosecute the case at the election.
His interest in policy remains undimmed from his start in life with a first-class honours degree in economics and commerce from the University of Newcastle,his home town,where he was raised by parents who had migrated from the Greek island of Cephalonia.
“I’m not saying I’m going to solve all these problems by myself but I want to contribute to the debate,” he says.
“One thing I’ve taken from being away and being ill is that time is finite and you’ve got to get on with it.
“It’s taught me to savour every day,to not just rip through the day and do this and do that,but to actually savour having every day.
“We don’t have infinite time. Time can run out. So if you want to do something,do it now,don’t put it off. You won’t necessarily always have the time.”