The results are in...Rilley's tumour has been graded!
We received a call from Rilley's local vet tonight. Dr. Ewing had been speaking with Dr. Pluhar in Minneapolis and Rilley's tumour has finally been graded. When Rilley had his surgery last Thursday, it was thought that because the tumour had grown so much and had begun to attach itself to his brain that it would receive a grade of II or III.
For reference, World Health Organization (WHO) defines the various grades of a meningioma as follows:
Rilley before surgery with his original MRI superimposed.
Grade I: Benign Meningioma
Grade II: Atypical Meningioma
Grade III: Malignant (Anaplastic) Meningioma
Obviously we've been hoping that the tumour would not receive one of the higher grades...so, drum roll please!
Rilley's meningioma tumour is a ...GRADE I!!!!
We cannot say how relieved we were to get this news! It means that it is the grade of meningioma that has the lowest risk of recurrance.