Three in a Million

I am one in 350,000. I really wanted to be one in a million, but it's 350,000. That's according to the doctor of someone in my ependymoma (a rare brain tumor) support group. According to that doctor, at age 50, one in 350,000 people have a brain ependymoma. An ependymoma, according to almost anyone, is 2.2 percent of all brain tumors.

Somehow, being three in a million just doesn't sound as special as I feel I am. I once heard a "This American Life" where a mathematician's girlfriend asked him if she was the only one in the world for him, and he replied that she's probably one in four hundred thousand. He thought that sounded good. She didn't. He needed a bit of the poet in his mathematical mind.

According to the 2010 census, 563,374 people reside in Seattle, where I live. Statistically, that means that two Seattle adults might have ependymomas, though with our quality hospitals, I suspect we may have a higher percentage here. I guess two in the whole city sounds a little more special than three in a million. I wonder if I've ever met that one other person. That would be unlikely.

A few years ago, I worked for an educational technology company, and an African-American friend of mine was sent to Maine for a sales jaunt. She said that as she pulled into a gas station to fill up, another customer, an African-American man, got out of his car at the same time. Two African-Americans at the same gas station in Maine. Probably as unlikely as two people in Seattle with ependymomas at the same coffee shop, though it was probably easier for them to recognize the unlikeliness than it would be for us, as I've never made an announcement in a public place: "Excuse me. Does anyone else here have an ependymoma?"

Accordng to the website "True Knowledge" (intriguing title), the population of Raleigh, NC, the city where David Sedaris and I grew up, is 402,589. That means that in Raleigh maybe I would be the only one in the city with an ependymoma. If I moved there, I wonder if it's more likely that there are two people with ependymomas or just one, since I would have increased Raleigh's population by the insigificant number of one, but I already know I have an ependymoma, so would it be likely that there would be two of us?

Somehow, I suspect this mathematical conundrum is like the "Let's Make a Deal" math problem. Do I stick with door number one or change to door number two? Stick with door number one. I'll stick with my ependymoma, thanks. Actually, I've already given it up. Even more complicated.

Special enough. Mary