Initially, he had serious doubts about whether audiences would be able to laugh at what, for most of us, is the ultimate health nightmare.
“I was really nervous about it because I’d never spoken on stage about anything that dark before,” he says. “But then surprisingly it went really well. I think maybe people were laughing because they knew it was so real. They could see I was sharing something that is really vulnerable.”
And once he started re-casting his cancer and treatment as something to laugh about, the material flowed surprisingly easily – from jokes about making sperm donations to people’s eagerness to tell him he now shares with Adolf Hitler the distinction of having only one testicle (Shafar is Jewish).
“The jokes were actually quite easy to write, to be honest,” he says. “I didn’t really have to come up with anything. I just had to say things that I was feeling and thinking and going through at the time.”
However, Shafar recognises that for many people, especially those who have had people close to them die of cancer, his taboo-busting material may go too far.
And for that reason he is very clear his humour is directed only at himself.
“I’m only talking about my own cancer, my own diagnosis,” he says. “At no point do I make a broader statement about cancer survivors or cancer generally. I don’t think I have the authority to do that. I don’t know anything about other people’s experiences, so I just don’t try to talk about it.”
One of the broader issues he does take aim at, though, is the language often used around cancer, in which patients “battle” or “fight” the disease.
“It’s really immature and shallow,” he says. “I would never use that kind of language because I know what it really is. People don’t ‘valiantly battle’ against cancer, they suffer through it and it’s shit.”
And Shafar freely admits the nature of his particular disease has given him some free kicks in the comedy stakes.
“I think that of all the cancers [testicular cancer] is probably the funniest one,” he says. “If I was going to get a cancer, that’s the one to get.”
Michael Shafar is at Marrickville’s Factory Theatre on January 25
Nick Galvin is Arts Editor of The Sydney Morning Herald