'General Hospital’ Star John J. York Reveals 2 Blood and Bone Marrow Disorder Diagnoses: 'This Isn't Goodbye'

General Hospital star John J. York revealed that he has been undergoing treatment for two blood and bone marrow disorders.

On Wednesday, the actor, 64, posted a video on X to update his followers on his condition after he shared on the platform last week that he would “be taking a brief hiatus” from filming the long-running daytime series.  

“I said I was going to give you an update on the reason I’m taking a little hiatus from General Hospital and here it is,” he said. “So last December of ’22, I was diagnosed with myelodysplastic syndromes, or MDS, and multiple smoldering myeloma — two blood and bone marrow disorders.”

According to the National Cancer Institute, myelodysplastic syndromes (MDS) are classified as “a group of cancers in which immature blood cells in the bone marrow do not mature or become healthy blood cells.” 

Multiple smoldering myeloma is a “precancerous condition that alters certain proteins in blood and/or increases plasma cells in bone marrow, but it does not cause symptoms of [myeloma] disease,” per NCI.

“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’m closing in on a blood stem cell transplant,” York said.

The soap opera star also said that he has “been working with some wonderful people at Be The Match to find a potential donor on their registry.”

“If it’s possible and you would consider being a donor, joining their registry, for not just me but thousands and thousands of other people who are in need of a donor, go to bethematch.org/matchformac,” he said. (Those interested in joining the Be the Match registry must be between the ages of 18-40.)

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“I just want to say thanks for all the support over the years. This isn’t goodbye, this is just, ‘So long,’ ” the TV actor assured his fans. “I’ll have to take a break [from General Hospital] for at least three, maybe four months, but I’ll be back.”

“Thanks a lot. Check out Be the Match. Do whatever you can. Thanks for your patience, thanks for your time, thanks for your prayers. I’ll keep you updated. Talk to you soon,” he concluded his message.

York is best known for his portrayal of Mac Scorpio on ABC's General Hospital. He has appeared in nearly 650 episodes of the daytime soap since his character was first introduced in 1991.