As I mentioned in my last couple of posts, St. Jude sent off a bone marrow sample to a lab in San Francisco who specializes in ultra-sensitive detection of minimal residual disease (MRD) in patients with lymphoid cancers.
The results: Deep sequencing shows NO evidence of residual leukemia. So, an independent review of the results was requested and conducted by a well respected pathologist in Singapore. While John’s MRD was difficult to interpret she would favor “MRD NEGATIVE”.
YES, this result is discrepant from the MRD results at St. Jude and what we believed to be low-level MRD these past seven months is no longer considered residual leukemia.
You are probably asking yourself the same question I did – did St. Jude make a mistake all these months? No. We were given several reasons for the discrepancies by the third party pathologist in Singapore – most are above my head. I can’t “yet” comprehend them (but I WILL). However the most logical explanation is easiest to explain to you all: the T-Cells that are staining a dim violet (MRD) could most likely be a population of post-transplant T-Cells regenerating. They express surface markers that would indicate that they are normal activated T-Cells and the staining in these cells is probably false – a pseudo MRD.
When we return to St. Jude in February all tests will be re-run and we’ll meet with Dr. Pui and team to go over these results until we all understand them. We’ll also come up with a plan on how to monitor John going forward.
As you can imagine the updated results bring an array of emotions – most of which I’m not ready to share - sorry. We are still processing the news and everyday seems to bring a new reaction. We’ve been on this rollercoaster a long time and we know better than to declare victory over John’s leukemia. To protect our hearts we are just moving forward with the possibility that John is cancer free but with the reality that John’s leukemia is extremely complex and high-risk. Every day is a gift and everything can change tomorrow.