The actor took to social media on Wednesday to share the news of his ongoing health battle.
General Hospital star John J. York is opening up to fans about his recent diagnoses and his ongoing health battles.
York has starred as Mac Scorpio on General Hospital since originating the character in 1991. He first announced he'd be taking a hiatus from the series earlier this month.
York took to X (Twitter) on Wednesday to explain what he's been struggling with since late last year.
"Last December, of '22, I was diagnosed with myelodysplastic syndrome, and [Smoldering Multiple Myeloma], two blood and bone marrow disorders," York shared. "Over the past many months, I've had three bone marrow biopsies, many chemo treatments -- I have another one coming up in a couple of weeks -- and I am closing in on a blood stem cell transplant."
According to the National Cancer Institute, myelodysplastic syndrome (MDS) is a type of cancer "in which immature blood cells in the bone marrow do not mature or become healthy blood cells."
Additionally, Smoldering Multiple Myeloma is a slow-growing form of multiple myeloma, which is a form of cancer that affects plasma cells, causing them to overproduce one type of antibody.
"I've been working with some wonderful people at Be the Match, I've been working with some wonderful people on their registry," York said, before encouraging his fans to consider donating to the organization or joining the donor registry, "Not just for me for for thousands and thousands of other people who are in need of a donor."
"I just want to say thanks for all the support over the years," York shared, explaining that this "isn't goodbye," but that he will "have to take a break for at least three, maybe four months. But I'll be back!"
"Thanks for your patience, thanks for your time, thanks for your prayers," he concluded. "I'll keep you updated."