Months after Christie Brinkley revealed her skin cancer diagnosis, the 70-year-old supermodel is opening up about the surprising moment she found out. 

During Tuesday's episode of "Today," Brinkley revealed she "wasn't even scheduled for a checkup" at the time her cancer was found and nearly didn't ask about the concern that led to her diagnosis. 

"I was accompanying my daughter to the dermatologist, and I was in the room, and [the doctor] had this little magnifying glass out, and he's looking at a couple of things that she was worried about," Brinkley said. "I thought, 'There is that little spot right on the side of my head right here.... Should I say anything? It's not my appointment.'" 

SUPERMODEL CHRISTIE BRINKLEY TURNS 70 WITH PLANS TO ‘EAT, PRAY, LOVE’

Christie Brinkley smiling

Christie Brinkley revealed she "wasn't even scheduled for a checkup" when she discovered she had cancer. (Sonia Moskowitz/Getty Images)

"Then right at the very end, as he was putting away his little thing, I said, 'Before you put that away, do you think you could just look at this?'" Brinkley asked the doctor. "He looked and he goes, 'We've got to do a biopsy immediately. This is something.' Then the biopsy came back as cancer."

"They took care of it, and luckily, my hair grows in that direction, but the scar is barely noticeable," she said, referencing her surgery. 

The mother of three first announced her diagnosis in March by sharing a series of photos of her surgery scars on social media. 

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"The good news for me is we caught the basal cell Carcinoma early," she wrote in part. "And I had great Doctors that removed the cancer and stitched me up to perfection like an haute couture Dior…"

Christie Brinkley after having skin cancer removed

Christie Brinkley shared that she had basal cell carcinoma on the side of her face.  (christiebrinkley/Instagram)

Brinkley shared with her Instagram followers that she will be making lifestyle changes now that she has received her diagnosis.

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"The good news for you is that all of this can be avoided by being diligent with your sun protection!" she wrote. "I got serious a bit late so now for this ole mermaid/gardener, I’ll be slathering on my SPF 30, reapplying as needed, wearing long sleeves and a wide brim hat. And doing regular total body check ups..that is a MUST !"

Christie Brinkley bloody cancer removal

Christie Brinkley revealed her cancer diagnosis in March. (christiebrinkley/Instagram)

"The Doctor was looking at each freckle with a magnifying glass… it wasn’t my appointment so I wasn’t going to say anything but at the VERY end I asked if he could just look at a little tiny dot I could feel as I applied my foundation," Brinkley wrote. "He took a look and knew immediately it needed a biopsy! He did it then and there! So make your own good luck by making that check-up appointment today. And slather up my friends!"

Ahead of her milestone birthday in March, Brinkley told People magazine that she's looking forward to the next decade and has quite a lot to check off her bucket list. 

"I still have to see India," she shared. "I’ve never been to Tahiti or Thailand. I want to go to Bali also. I’ve got to do an eat, pray, love."

Christie Brinkley New York event

The supermodel turned 70 in February. (Getty Images)

Brinkley told the outlet she is approaching 70 "with a lot of reverence and emotion." She explained she feels similar to when she turned 50, saying both birthdays are "a time when you look both back and forward." 

"The big 7-0 is another one of those [ages] that’s up there in giant block numbers that loom over," she said. "At 62, you start thinking, ‘Well, I'm almost 70.' It cast a shadow all over that whole decade down."

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