1 in 25 million: How an unlikely bone marrow match saved this Montrealer's life

Susan Doherty wrote four letters toher bone marrow donor in the two years before he was allowed to see any of them.

She wrote the first 100 days after receiving the transplant that ultimately saved her life from a very rare and deadly illness calledHemophagocytic Lymphohistiocytosis (HLH).

She wrote the secondon the anniversary of her survival; the third, whileshe was in Berlin after that, and the last, two years after the first, late last summer.

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Doherty, her husband and two children are now heading to England, where on Thursday they'll meet William Ashby-Hall for the first time.

Bone marrow donors aren't allowed to hear from the recipientoftheir bone marrowuntil that person has survived past the two-year mark of the transplant, according to Doherty.

When she and Ashby-Hall, 25, finally got on the phone Sept. 5 and compared stories, Doherty says she realized thematch had been "divine timing."

Ashby-Hall, who was 23 at the time,had just joined the bone marrow registrywhen he learned his typematched Doherty's theonly match out of 25 million names on the list, she says.

Doherty, a spunky 61-year-old Westmount writer and fitness teacher, was diagnosed in 2015 with HLH, a life-threatening immunodeficiency that is treated with chemotherapy.

Doherty's illness was so destructive, shehad to begin treatments the very day she was diagnosed. Those treatmentswere successful, but she relapsed a little less than a year later, in January 2016.

Donor wasn't on list yet, when Doherty needed transplant

Doherty was given a 50 per cent chance of surviving, but only if a bone marrow donor matching her profile could be found within weeks.

A German donor dropped out. Then her brother was found to be a perfect match until doctors ran a test to see if he had the HLH gene, which meant that he could reinfect her. He did.

Thattransplant was cancelled, and Doherty found herself back at square one.

"The existential pain, I've always been saying, is far worse than the physical pain," Doherty toldCBC Montreal'sDaybreakTuesday.

Not for one second did he back down.- Susan Doherty of her bone marrow donor, William Ashby-Hall

"That period of waiting for the match, waiting for the date of the transplant, was perhaps the hardest month of this whole three-year journey.

Human rights victory

Ashby-Hall, who was 23 at the time, wasn't even on the donor list yet as Doherty spent her days waiting. He'd donated blood that winter, and a nurse asked him if he'd like to join the bone marrow registry.

The day after his marrow was tested, he got a call informing him he had matched with a Canadian woman, Doherty says,"and that he had the potential to save a life."

"He didn't hesitate. Not for one second did he back down."

Beyond the sheer luck of it, Doherty calls the match a "human-rights victory."

Ashby-Hall is married to another man, and in Canada, men who have had sex with other men in the previous yearcannot donate blood.

If they want to be on the bone marrow registry, they must undergo further testing, according toHma-Qubec."There was no match for me in Canada, but luckily the British rules are different," Doherty said.

Doherty says she's been imagining what meeting Ashby-Hall will be like.

"I mean, he's such a sensitive man. Like, how many 23-year-old men walk in to give blood in the first place?" Doherty said.

"My children said, 'Mom, you know, you can't wrestle him to the ground,' but I know that that's going to be really hard."

Listen to Susan Doherty's interviews with As It Happens and CBC Montreal's Daybreak: