Thursday, May 24, 2012

Sometimes I Hate My Genes

I haven't posted here in awhile because I've been trying to get my thoughts together. This is a long story and I believe it would be best told beginning with some background.

When I was diagnosed with colon cancer I was sent to see a geneticist once I arrived at Johns Hopkins. He looked over my family history of cancer and told me he believed I had something called Lynch Syndrome. Basically Lynch Syndrome is a deletion of one of your DNA mismatch repair genes. Essentially when your DNA is replicating and it makes a mistake your mismatch repair genes correct those mistakes. When you are missing one of those genes it is harder to repair the mistakes made during replication. Those mistakes begin "piling- up" and eventually lead to the development of cancer. Typically with Lynch Syndrome colon cancer is the most common, followed by endometrial cancer, though there are many cancers that can arise.

Since my cancer diagnosis was in 2008, one year before the genetic in-discrimination act was put in place, I was hesitant to undergo genetic testing for Lynch Syndrome. We decided that it was obvious I had Lynch so I could put off my testing if I proceeded with treatment like I had it. I had a more drastic surgery to prevent future cancer and I get screened annually, if not more often than that. They did however do two tests on my tumor: a microsatellite instability test and immunohistochemistry for MLH1, MSH2, MSH6, and PMS2. Normal results would show up as microsatellite low and all four proteins expressed. My test results were microsatellite high and proteins MLH1 and PMS2 were not expressed. So I had abnormal results. When MLH1 and PMS2 are missing in the immunohistochemical testing then they test MLH1 for hypermethylation. If this test is negative, as mine was, then they suspect that MLH1 is deleted aka. you have Lynch Syndrome. The nest step is blood testing, which is the part I put off.

Until last month.

I think part of me put it off because I was worried it would be negative. Sounds weird huh? Well, when over 14 members of your family have had colon cancer and you were diagnosed at 22, you want answers. I wanted to know the reason. While having a genetic disorder is not something exciting, it is an answer. There is a lot of research that has been done and there are screening methods you can follow and your family members can get tested. It offers hope because you know longer have to wonder why your family has so much cancer.

My genetic test results came back on May 14th. I was negative for a MLH1 deletion. *Sigh*

They are testing me for a PMS2 deletion but for several reasons we expect that to be negative too. So what does this mean? They still believe I have Lynch Syndrome. Basically there are two scenarios: 1. I have a MLH1 mutation that is just not able to be detected with current testing, or 2. I have a deletion in another gene that hasn't been discovered yet that regulates the MLH1 and PMS2 genes. So essentially we are left with no answers.

But the most frustrating part is that now none of my family members can get tested for Lynch. That was the one light at the end of the tunnel for all of this. The idea that now my family could know if they are at risk for these cancers so that they can get proper screening and catch it early. Most people won't screen unless they KNOW they have it. And now they can't know. So frustrated.

But now, in a positive light, maybe this is why I am going into cancer research. Maybe I can figure it out one day. Maybe. I hope somebody does. I wonder how many other families out there have had similar genetic testing results? I was told that less than 10% of Lynch families have an "unknown" gene. I'm itching to do a study on this... if only I already had my PhD :( 4-5 more years of waiting... but I guess when my family has been waiting over 100 years, 4-5 seems pretty short.

Anyone else had frustrations with genetic testing?

No comments:

Post a Comment

"Life's journey is not to arrive at the grave safely in a well preserved body, but rather to skid in sideways, totally worn out, shouting..... 'WHAT A RIDE!'"