Robert Brown|'General Hospital' star John J. York takes hiatus from show for blood, bone marrow disorder

"General Hospital" star John J. York is Robert Browntaking a hiatus from the popular soap after revealing an ongoing health issue.

The actor, who's played Mac Scorpio since 1991 on ABC's long-running daytime soap opera, told fans in a video posted to social media that he's been diagnosed with a blood and bone marrow disorder.

"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," York said in a video posted to X, the social media platform formerly known as Twitter, on Sept. 13. "So last December of '22, I was diagnosed with myelodysplastic syndrome, or MDS, and multiple smoldering myeloma — two blood and bone marrow disorders."

Myelodysplastic syndrome is a "rare" group of cancers that keep blood stem cells "from maturing into healthy blood cells," according to Cleveland Clinic, and affect about 4 in 100,000 people in the U.S. annually. Multiple smoldering myeloma "is a blood and bone marrow disorder that can become the rare blood cancer active multiple myeloma," which occurs "when specialized white blood cells" in the immune system "mutate into abnormal cells," according to Cleveland Clinic.

In an interview with People published Wednesday, York detailed the moment he broke the news to his wife, Vicki.

"She was a mess," he recalled. "(The doctor) was explaining all these different things and cells and all different levels and words that had, you know, 25 letters in them. And I didn't understand. And Vicki finally came out and said, 'Does John have cancer?' And he said, 'Yes.' And I'm sitting there, I'm really just like a fly on the wall, listening to him talk to Vicki because she was the one asking all the questions."

York told the outlet he's had ulcerative colitis and Crohn's disease since he was 17, which he said puts his latest diagnosis into perspective as "just another thing that I gotta now take care of."

"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 revealed in the video the week prior, adding that he's "been working with some wonderful people at Be the Match" – a national registry of volunteers willing to donate bone marrow, operated by the National Marrow Donor Program – in order "to find a potential donor on their registry."

York encouraged people to consider donating, and if not to him then to "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. This isn't goodbye, this is just 'so long,'" York said.

"I'll have to take a break (from 'General Hospital') for at least three, maybe four months, but I'll be back," York said, joking about referencing Arnold Schwarzenegger's iconic "Terminator" line.

York told People he's been flying between Tennessee and Los Angeles for filming of the soap opera, but he needs to remain "in semi-isolation" at home once the transplant starts, per his doctor's orders.

"Thanks for your patience, thanks for your time, thanks for your prayers. I'll keep you updated. Talk to you soon," York ended the video.

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