Dear Editor,

We thank Dr Mattei for his letter: Umbilical Cord Stem Cells The Hidden Swan in a Family of Ugly Ducklings. He has identified an area not covered in our review of stem cells in the development and treatment of glioma.

Dr Mattei makes the case for the potential application of umbilical cord stem cells with respect to glioma. Indeed, they comprise a source of multipotent cells for more widespread applications within the field of regenerative medicine and regenerative neurology.

As Dr Mattei makes clear, the neurosurgical armamentarium in the twenty-first century is likely to contain more than ultrasonic aspirators and bipolar forceps. It is up to us as neurosurgeons to determine how biological tools can best be developed and applied. To do this we need to be aware of the weaknesses as well as the strengths of the technologies as they evolve. Dr Mattei has identified another area for future development. Nevertheless, patient safety must be our priority, so well-designed clinical trials will be essential. Such trials will be predicated on rigorous pre-clinical studies. This is where we are now.

There is still a long road ahead, but the journey has begun.