Wednesday, December 11, 2013

ASH 2013 - Chronic Infection, MGUS, & Myeloma

Paper 3116: Chronic Infection, a Neglected Cause Of Development Of Monoclonal Gammopathy Of Undetermined Significance (MGUS) and Myeloma

According to this French paper, it is well known that certain chronic infections can cause lymphomas and chronic leukemia, because the infection annoys the cells until they ultimately make a mistake and become malignant (my words - theirs are undoubtedly more clinically correct but well above my pay grade).  Apparently, something similar can happen to our plasma cells, turning them into malignant myeloma cells.

Indeed, the International Myeloma Foundation says "Several studies have linked myeloma to HIV, hepatitis, herpes virus infections (especially herpes virus 8), Epstein Barr Virus (EBV), as well as new 'stealth adapted' viruses such as mutated cytomegalovirus (CMV)."  The studies show that people with those infections are somewhat more likely than average to develop MGUS or myeloma.

Realistically, though, what is the risk for any one person?  The French researchers examined the question another way.  Since specific plasma cells are engineered (by our bodies) to attack specific threats, they tested the malignant cells, by examining the monoclonal immunoglobulins (M-spikes) that they produce, to see what threat they were designed to fight.  They tested the M-spike of 101 patients for reaction against eight different viruses and bacteria, and found that 23% of the patients' cells were specific for HCV (hepatitis C), EBV, or H. Pylori, a bacterium implicated in chronic stomach ulcers.  Any of the three infections can be present without symptoms.  For these 101 patients, no reaction was detected against the other five threats which, by the way, included CMV.

The authors propose: "Efforts should be made to identify the subsets of patients with (M-spikes) specific for HCV, EBV and H. Pylori, preferably at the MGUS stage, as anti-infection treatment is expected to cure MGUS and prevent progression toward myeloma."

A possible cure for MGUS and prevention of myeloma for some patients - wishful thinking?  I'm not a doctor, but I believe that H. Pylori can usually be cured with appropriate antibiotics.  I doubt that a cure is available for either HCV or EBV, but perhaps there are treatments which could reduce their impact on the immune system.

Should doctors be testing to identify patients with M-spikes specific to those infections?  Is it possible that, for some people with symptomatic myeloma, these infections could even cause further mutations of already-malignant myeloma cells, thereby assisting that myeloma in its deadly quest to eventually defeat every treatment?  Can anyone add more information?

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