The Channel 9 personality shared a selfie of her bandaged head to Instagram, writing that she was “counting my blessings they’re NOT melanomas”.
“Can’t overstate enough to get your skin checked & slap on the sunscreen!!” Gardner added.
Gardner previously had to get a skin cancer removed on her back last year and a squamous cell carcinoma cut out of her face in 2015.
Gardner’s cancer scare comes as she and co-host Karl Stefanovic suffer the worst Today ratings in four years.
The Nine breakfast show has been bested by Channel 7 rivals Sunrise in 22 of the 23 survey weeks this year.
According to media analyst Steve Allen, the tension between Stefanovic and Gardner might be putting viewers off the Channel 9 show.
“Anytime the public sense that there’s not cohesion and there’s some kind of tension between on-air hosts, I think it’s going to have a negative effect and lose viewers,” Mr Allen told news.com.au.
Gardner joined Today earlier this year, replacing Lisa Wilkinson after she abruptly quit the role over a pay dispute in 2017.