Our patient was discussed at MDT and as many have suggested, he is treated with intensive chemotherapy.

MATRIX – HD MTX, cytarabine, thiotepa and rituximab is the current regime recommended in the UK.  Intrathecal chemotherapy is not advocated in the BSH guidelines.  MTX should be delivered at doses of at least 3g/m2 with an infusion time of 2-4 hours.

He had a repeat MRI after two cycles showing complete remission.  His stem cells were harvested after the second cycle. He goes onto to have a further 2 cycles of MATRIX followed by autologous stem cell transplant.

Repeat MRI at 6 weeks following treatment shows no evidence of disease.  However 5 months following ASCT he presents with slurred speech and further MRI shows two new cerebral lesions.

What is your differential? Management plan?