Monday, September 10, 2007

New CLL Info

Thanks to Chaya Venkat's excellent advocacy, four CLL experts have posted answers to her questions about stem cell transplants as treatment/cure for CLL. It's too soon for Dave to be pursuing this option, but not too soon to be thinking about & planning for it. Although whenever I mention it to him, he dismisses it with, "They almost never work."

Regarding the question of outcome for this procedure, Dr. Andrew Pettitt wrote:
There are essentially three possible outcomes following allografting: (1) the disease is cured; (2) the disease is not cured but the patient survives the procedure; and (3) the procedure itself is fatal. It is always difficult to assign each of these outcomes with a precise probability value. However, taking an ‘average’ CLL patient (of course there is no such thing) who is in a reasonable remission (whatever this means), I find it helpful to think in terms of a ‘rule of fifths’, i.e. there is a 3-in-5 chance of the transplant working, a 1-in-5 chance of the disease relapsing, and a 1-in-5 chance of the transplant shortening the patient’s life due to complications. These figures are only crude approximations of the available data but nevertheless give patients and their families something simple and tangible to chew over. ... Another extremely important issue to be factored into the equation is that, irrespective of the final outcome, the procedure is very likely to have a negative impact on quality of life for a year or more owing to frequent hospital attendances and the problems associated with graft-versus-host disease (GVHD) and infection.

And Dr. Terry Hamblin wrote:
What makes CLL so much worse than other conditions for which mini-allografts are performed is how immunosuppressed the patients are before the transplant. Patients with CLL are immunodeficient from the start in a way that patients with say, MDS are not. Fludarabine, (the drug that that Dave has been getting - Anna) is extremely immunosuppressive, producing AIDS-like levels of CD4+ cells for around 2 years. If the patient has been previously exposed to CMV or EBV (which Dave has - Anna) the reactivation of one of these herpes viruses is on the cards. Most guidelines have suggested that allografting should be reserved for patients refractory to fludarabine containing regimens or those who relapse within one year. This seemed like good advice at the time, since the risks of transplant in CLL are so great that one would not want to expose a patient to them if there was a reasonable chance of prolonged good quality life on immunochemotherapy alone. Remember that before mini-allo's, allografts in CLL carried a treatment related mortality of 40%. It had been hoped that mini-allo's would reduce this, but on what has been revealed so far, this has not been the case.

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