(CNN) To the travelers at the train station in Cologne, Germany, they probably seemed like two old friends embracing after a long time apart. But it was actually a long-awaited meeting between strangers -- a two-time cancer survivor finally seeing the bone marrow donor who saved her life.

This picture shows Beth Wilson on the day of her transplant, January 21, 2016.

Beth Wilson, 36, an intensive care nurse, was diagnosed 10 years ago with adenocarcinoma in her small intestine. She went through six months of chemotherapy and beat the cancer, but was then diagnosed with leukemia, one of the risks of chemo. Wilson said she believes the chemo was the likely cause.

Wilson then sought treatment at Atlanta's Northside Hospital, where doctors suggested a bone marrow transplant as the best way to treat her leukemia. Since Wilson does not have any siblings, and her parents were only a 50% match, she was put on the donor list. Doctors warned that it could take years before a match was found -- but not only did Wilson end up with two potential donors, but they were both 100% matches, which is extremely rare.

A German university student was a match

Alina Theine, 24, was one of those matches. The resident of Cologne, Germany, had registered as a stem cell donor as part of a registry drive at her university. She said she thought the chances of being matched were slim.

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