Inspirational 13-year-old Deryn Blackwell is facing up to a heart-breaking setback in his battle against a rare combination of cancers after learning that his bone marrow transplant has failed.
The Wayland Academy student was diagnosed with leukaemia aged 10, and subsequently developed Langerhans Cell Sarcoma as well – one of only six cases in the world.
After chemotherapy in Addenbrooke's Hospital in Cambridge he was taken for specialist care at the Bristol Royal Hospital for Children, where he has been treated since February.
Last week, the teenager made a joyful return home for a Bank Holiday with his family in Watton, marking an upward peak on their 'rollercoaster' of emotion.
A bone marrow transplant in March had offered hope that Deryn's months spent in hospital could be nearing an end, with early signs suggesting the graft had taken well.
On Friday, doctors told the family that they had successfully treated the youngster for graft-versus-host disease (GVHD), a common complication following tissue transplants.
But the family's elation at this progress was short-lived, as it was immediately followed by the heartbreaking news that the drugs given to combat a virus, which Deryn's weakened body had been struggling to fight since April, had effectively killed his new bone marrow.
Deryn's mother Callie said it felt like 'back to square one' after seven months in hospital undergoing operations and transfusions.
On Friday, doctors reintroduced a 'back-up' supply of Deryn's own bone marrow, kept in reserve before his 'conditioning' started in February, in case all else failed.
The hope is that with his own cells returned, his immune system can recover and fight off the virus, with the possibility that he could be home within four to six weeks.
But his family's optimism is tempered by the knowledge that these are the very same cells that needed to be replaced by the transplant in the first place because, they could contain the two cancers that Deryn fought so hard against.
His mother said: 'Once the bone marrow goes in and grafts we will be back to exactly where we were in February before the transplant, and it will be like all of these last seven months will have been for nothing. We had to try – we did try and it didn't work. It is great to think he can be rescued, but obviously he has now been given cells which might have cancer in them, which was the reason they were to be eradicated in the first place. It is six of one, half a dozen of the other.
'Having said that, we were originally supposed to finish the leukaemia treatment in October 2013, so we have come full circle and we are still where we should have been if the transplant had not happened. They gave him as much chemotherapy as they could have done, so we are not really left wondering if we could have done more.
'Because of Deryn's very rare cancer, they didn't even know whether the bone marrow transplant was going to be enough to stop the cancer coming back.
'So we were always going to be looking over our shoulders, whether he had got his own bone marrow or someone else's.
'We have still got to be vigilant and keep an eye on him.
'We just have to take one day at a time. I don't get excited any more, because I know there is always something around the corner. If the bone marrow grafts and it kills this virus, then that is positive enough for me.
'Ultimately he is still here, and we are very, very lucky in that case. We have seen so many children that are not here any more, and their parents have been left behind. So we are the lucky ones.
'We are lucky that there are options. We are lucky that we have never heard the words: 'Sorry, there's nothing more we can do'. We always count our blessings.'
The latest turn has left Deryn lethargic and tired – but not defeated.
In her online blog on Friday, Callie says: 'The bone marrow that has gone in this morning has been through the horrendous four months that Deryn had in Addenbrooke's. It has endured as much adult chemotherapy that they could throw at it.
'Deryn said that if any cells have survived that then he'll happily let it live in his body because it deserves a place for being so tough!
'Deryn doesn't want another transplant – Deryn wants to go home and enjoy his life.
'He told me that he's spent far too many years fighting, missing out, being ill, feeling like death and that now he just wants to go and live.
'He so desperately wants to go on holiday, be with his friends, live a 'normal' life away from all of this, and I don't blame him one bit.'
Tweet Deryn at @_DoEveRYthiNg and follow his mother's blog at www.doeverything.org.uk
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