On Friday, Griswold posted new content to the short-video sharing app in which he says, "Because of two kind strangers I avoided skin cancer."
The software developer with nearly 476,000 TikTok followers said a week after viewers noticed the irregular growth, he went to a dermatologist who performed a biopsy. A week later, he was told it needed to be removed. On Tuesday, he had the mole and an area around it cut out, he said.
Griswold described the growth as "a moderately atypical mole continuing to change and heading toward melanoma." He said he was advised that the issue has likely been resolved, but that "there still is a chance" growth could re-emerge.
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Dr. J. Leonard Lichtenfeld, deputy chief medical officer of the American Cancer Society, said the mole indeed looked "irregular" and "of concern."
"This is the type of lesion we talk about and try to have people understand could possibly be cancer," he said.
It all started in mid-December when Griswold posted the video about marriage. In the clip, he said "back scratches always turn into pimple-popping sessions." He demonstrated those words with imagery of his back.
Two viewers, Griswold said, noticed the mole and reached out to advise he should have it checked out.
One of those two, 23-year-old Georgia resident Lizzie Wells, said she's a melanoma survivor who's training to be a neurosurgeon. When she spotted the lesion, she commented on the post and tracked down Griswold's email address to warn him.
"You don't look at your back," Wells said. "Imagine if he hadn't created the TikTok about pimple popping?"
She said she relied on parts of the "ABCDE rule" of checking out skin growths: It calls for looking for asymmetry, a border that could be irregular, color that's inconsistent, a diameter that's greater than the size of a pencil eraser, and evolution into a different size, shape or color.
Griswold said he thanked the tipsters directly.
"TikTok saved my life," he declared on his latest video.