When they were monitoring Liz over the recent years, watching her myeloma slowly start, they watch something called the "lambda light chains" in her blood. Now, I have no idea what these are, so I will refer to them here as "the magic number" as that is something we can all understand.

When Liz had her first bone marrow biopsy, back in 2006, her magic number was somewhere in the region of 200 - I believe that the "normal" figure is closer to 20 - so that was when we knew that myeloma was coming.

The magic number rose slowly over the years and last year (2011) it was 1,000 in July, again in August and again in October. When her blood test came through in January it had gone up to 2,000 and this was when the consultant said that treatment would probably start this year.

When Liz was admitted in mid-March it had shot up to 5,000. This is a huge increase over a very short period - a very aggressive and completely unexpected sudden onset. But, because there was nothing that could be done about it while the ensuing pancreatitis was being treated, the myeloma ran unchecked, and at it's worst, by the end of March the magic number was 7,000.

The treatment for myeloma is in two parts. The first is the four to six 4 week rounds of chemo, which kill off the cancer cells in the bone marrow, and how effectively it is doing this is shown by the magic number. They will start the second part of the treatment - the stem cell transplant - if the magic number can be reduced to about 10% of it's original value - in Liz's case 700. They would prefer to have it reduced below 200, in an ideal situation it would be below 1% (70 in Liz's case), and 20 would be wonderful.

They need to get it down before the stem cell transplant because it is a measure of how much of the myeloma Liz will carry forward across the transplant. This has a direct effect on the length of the remission period - the lower the number, the longer the remission.