As I'm going to be wittering on at length about this transplant and the various twists and turns I'll encounter on the way perhaps it would help if I outlined what exactly is going to happen as I understand it? Hematopoietic stem cell transplantation, to give it it's full name, is a process by which blood stem cells are extracted from the bone marrow or the blood and then returned to the donor or recipient after a period of high dose chemotherapy; in fact another way of describing the prcedure is as "high dose chemotherapy with stem cell rescue." The rationale is that by putting some stem cells in the bank (or deep freeze) it then allows the doctors to smash you with lethally high doses of chemo knowing that you've got the back-up of those cells which can then be returned and rescue you from what would otherwise be a life threatening situation. The hope is that by destroying much if not all of the bone marrow you pretty much eradicate all of the disease at the same time, or in American military parlance "bomb it back to the stone age." As my cancer is classed as low grade it should take it a good few years to clamber back through the iron and industrial ages to a position where it can again attack me with it's vast array of nasty weaponry!
This ladies and gentlemen is what is known as an autograft as I shall be getting my own cells returned to me. It is not a cure, however, as unfortunately as you return the cells you also return the disease and so it will re-appear.
An allograft on the other hand is the process by which cells are taken from a donor and given to the patient with the disease. This promises a cure as the stem cells in this instance are disease free and perfectly healthy. Hang on.....why am I not doing this? Well as with all transplants from a donor there is a risk of rejection, and in this instance it's that which has been transplanted in that does the rejecting. As the donated stem cells start becoming your new immune system they seek out and destroy anything foreign. This can be a good thing if there are any left over cancer cells that need dealing with but not so good when the alien bodies they identify are your liver heart and lungs! In order to try and prevent this doctors tend to give these transplant patients a course of steroids to damp down the immune response....but this too comes at a price as it increases the length of time you are vulnerable to infection, or neutropenic.
Neutropenia is a problem associated with autografts too but the length of time involved is much shorter, normally only a week to ten days or so. The dangers of the two procedures are starkly illustrated by the mortality figures which currenly stand at around 2-3% for those having an autograft and around 30% for allos! So on balance although I think I will have to have an allo at some point for now I'm not prepared to take the risk.
That's roughly it. They reckon it takes about a month once you get cracking. A week or so to fill you up with chemotherapy, a week to ten days to wait for the new cells to graft onto the bone marrow and get working and another couple of weeks or so to deal with any infections that come along (and they will!) and for the immune system to get back up to safe levels. You've also got to be making enough platelets and red blood cells too before they let you go home. Simple.
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