The biopsy results won't be back for another week or so, and I fervently hope that I haven't gotten any worse since my last biopsy in February. That would be kind of disappointing considering what I've been through since then. I fully expect that the flow cytometry results will show some minimum residual disease, since my recent immunofixation results keep showing a trace of Lambda monoclonal paraprotein in my blood. But that's OK. I've been told that this is normal and that transplant patients usually show various traces of monoclonal protein after the procedure. As long as the plasma level in my bone marrow is less than 5%, I will still be in Complete Response (CR).
My blood tests came back pretty good, although my WBC and neutrophils are still somewhat low from the consolidation therapy. As of now, I am on maintenance therapy consisting of 10 mg/day of Revlimid every day for the next three months. After that, they may increase my dose to 15 mg/day, depending on how I respond to the 10 mg dose. I don't have to go back again until Sept. 24, when I will get another blood draw and an infusion of Zometa. I should be on a monthly schedule of DFCI visits from now on, as long as I stay in remission.
In a previous post, I promised to revisit the issue of whether there is a potential link between Lyme Disease and Multiple Myeloma. Some of my anecdotal evidence from other patients (including my own experience) indicate some possible connection, but I wanted to find some hard data that might reveal whether there is a statistically significant correlation. My initial blog post on this subject was a bit fragmented and didn't include the best data sources. I did a Google search to see what other studies might have been done on this topic, but all I was able to find were some more anecdotal accounts of a possible link. So I guess the burden is on me to carry the torch here. By the way, since Lyme Disease is far more prevalent than MM, I assume that Lyme may possibly contribute to the pathogenesis (e.g., causal mechanism) of MM rather than vice versa.
I've now taken a little deeper look into this subject. Lyme Disease is a fairly recent phenomenon, with the number of cases increasing dramatically over the last fifteen years or so. If there is some correlation with MM, one would expect that those states or regions that have an unusually high incidence of Lyme Disease might start to show some increase in the incidence of MM over time. One good source I used is the CDC website that tracks Lyme Disease case and incidence data by state and year: http://www.cdc.gov/lyme/stats/index.html. Another good source is the CDC National Program of Cancer Registries (NPCR), which provides age-adjusted myloma statistics: http://apps.nccd.cdc.gov/uscs/cancersbystateandregion.aspx. In order to compare MM incidence from one region or state to another, it is necessary to age-adjust the raw incidence data to account for age discrepancies from one area to another. This is because MM primarily affects the older population. For the Lyme disease statistics, I could only assume that they were age-independent.
The good thing about the NPCR data is that they include the 95% confidence intervals for the state-by-state and regional MM data. I wanted to select a region with a large enough population to provide statistically significant results. It was therefore convenient for me to select the Northeast US region (New England and Mid Atlantic), consisting of the nine states of Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, Vermont, New Jersey, New York, and Pennsylvania. The NPCR data conveniently provides average age-adjusted MM incidence for this region and the total US, along with confidence intervals. I have summarized these data in the table below. I wasn't able to get exact correspondence for all of the years for comparison, but I don't think that makes a big difference.
It is interesting to note that this 9-state region has about 18% of the US population, but accounted for 75% of the Lyme Disease cases in 2008! The Lyme Disease incidence for this region was 39 cases/100K population, which is over 4 times the national average of 9.3 cases/100K. Looking at the MM incidence, the age adjusted incidence for this region for 2008 was 6.0 cases/100K, with a 95% confidence interval of 5.8 to 6.2. The US total age-adjusted MM incidence for the same year was 5.6 cases/100K, with a 95% confidence interval of 5.5 to 5.6. I consider these results to be conservative, since a more accurate comparison would be between the 9-state region and the remaining 51-state region, not the US as a whole. That would only increase the discrepancy from the numbers I am presenting here.
My interpretation of these results is that one can say with more than 95% confidence that there is a higher probability of contracting MM in this 9-state region which has a high incidence of Lyme Disease than in the US as a whole. To me, this seems to establish a statistically significant basis for concluding that Lyme Disease is a contributor to the pathogenesis of Multiple Myeloma. There, I've said it!
Now before any of you start sending my name into the Pulitzer or Nobel Prize nominating committees, just remember that figures don't lie, but liars can figure. I'm not sure that I have accounted for all possible variables that might influence these results. There may be other regional variations that I didn't consider that might possibly account for the observed variations. Someone researchers may have already looked at this and dismissed it for one reason or another. I'd be curious to know about any studies on this topic that I may have overlooked. I would also appreciate any comments or suggestions on my analysis approach, methodology, or any glaring errors that I may have made. Furthermore, I welcome any personal stories of MM patients who may also have a history of Lyme Disease.
|State||Population||Lyme cases||Lyme||MM cases||Age-adjusted||MM incidence|
|(millions)||2008||Incidence||2011||MM incidence||95% conf.|
|% of US totals||17.8%||74.6%||20.8%|