General Hospital’s John J. York Begins Blood Stem Cell Transplant Process to Combat Cancer (Exclusive)

General Hospital star John J. York has begun the process of a blood stem cell transplant.

“There’s still a long road ahead, but these next 100 days I would say is rocky terrain,” he told PEOPLE exclusively of the excruciating wait to see if his body accepts the transplant ahead of starting treatment.

The veteran actor, who has played Mac Scorpio on the ABC soap for 22 years, revealed in September that he had been diagnosed last December with two forms of cancer — myelodysplastic syndromes and multiple smoldering myeloma — both of which are blood and bone marrow disorders.

The search for a donor became top priority and, thanks to the efforts of BeTheMatch.org, a match was found. What followed was months of more tests — “a lot, a lot of tests,” he said — for both York, 64, and his donor to absolutely ensure that his body would adapt to the transplanted stem cells.

“It’s literally a whole new ballgame from then on. From what I understand — this is kind of how I received the information — has been like pre-game and practice,” York told PEOPLE leading up to the transplant process which began earlier this week.

It’s a grueling process, but York is staying focused and positive in a “this is what has to be done” way.

“The first week is an 8-day process of heavy-duty chemo, where I’ll probably lose my hair, and that’s OK,” he said. “And, you know, there’s just all kinds of issues. I could, I could pass away. I mean, maybe not from the chemo, but when the transplant starts. So after the eight days of these different chemo treatments that they’re doing, they’re basically wiping my body of what I’ve been living with in terms of my blood and DNA and all this stuff for my entire life. They’re wiping that clean and then they’re gonna put new stuff in me from the donor. And that’s going to be the new me.”

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After he receives the blood stem cell transplant, he goes through a “100-day process” in which he has to go to the hospital every day for 100 days to be tested. 

York explained, “If tests come back after, let’s say after 30 days or 35, 40 days, tests are looking really good, that would be wonderful. Then they may say, ‘You don’t have to come in tomorrow, come in the next day. And then we’ll test after that.’ That goes on for 100 days, and I would say the first probably 20 days [after the transplant] are the crucial days. From the first day of the transplant, I’m guessing 14 to 20 days out, they’ll be able to tell with testing daily how I’m receiving and accepting the stem cells.”

Then there is another year or two of medication and even more testing, some of which includes the painful process of a bone marrow aspiration and biopsy.

According to the Mayo Clinic, the procedure involves a doctor or nurse “inserting a hollow needle through the bone and into the bone marrow. … The bone marrow fluid (aspirate) and tissue sample (biopsy) are usually collected from the top ridge of the back of a hipbone (posterior iliac crest). Sometimes, the front of the hip may be used.”

“I thought I was done doing bone marrow biopsies, but I still have like five bone marrow biopsies out there. Those are just not my favorite things in the world to do,” York said, wincing. 

The star sounds very matter-of-fact about what is in store for him, adding, “Well, you know, what can I do? There’s nothing I can do about it. I said it before: one day at a time.”