Gliomatosis cerebri

GC is an aggressive, highly invasive and migratory glial cancer. The tumour is resistant to current therapies¹⁰, and the prognosis is usually poor. A number of factors make this condition hard to treat. They include:

• The tumour invades all surrounding structures as it grows. This means that surgery –other than a surgical biopsy- has no role as part of the therapeutic schema.
• The blood brain barriers (BBB) block the entrance of most drugs.
• The few drugs that penetrate the BBB have to get to the target and reside for as long as needed in the right concentration.
• Cancer cells have the ability to “spit out” drugs that are intended to kill them.
• We do not have a good understanding of the tumour microenvironment. We also do not have a good understanding of how cancer cells cross-talk with mesenchymal or immune cells permitting tumour growth and progression.
• We do not understand the molecular alterations and the key biologic pathways that are necessary for tumour initiation and stabilization.

The prognosis for children with GC is, unfortunately, similar to the one described in adults. Most children and adolescents diagnosed with GC will succumb to their disease within 2 years of diagnosis^10,11.

A few factors can influence prognosis. They include age of diagnosis, sex and low-grade pathology. Molecular studies of GC, primarily based on adult populations, have identified some promoter methylation markers such as IDH1, R132 H and MGMT as potential molecular markers of prognosis. The implications of these markers in paediatric populations, still remain unclear.⁶

Prognosis has also shown to be worse in very young patients (<10yrs) and adults, compared to adolescents.⁶

Given the poor prognosis of GC, conversations around the goals of therapy and quality of life are of utmost importance. These discussions should begin early in the care process. Incorporating palliative care or quality of life services can help patients and families manage symptoms, promote quality of life, and navigate care decisions. 

⁶George, E., Settler, A., Connors, S. & Greenfield, J. P. Pediatric Gliomatosis Cerebri: A Review of 15 Years. J. Child Neurol. 31, 378–387 (2016).

¹⁰Sanson, M. et al. Initial chemotherapy in gliomatosis cerebri. Neurology 63, 270 LP – 275 (2004).

¹¹Benjelloun, A., Delavelle, J., Lazeyras, F. & Dietrich, P. Y. Possible efficacy of temozolomide in a patient with gliomatosis cerebri. Neurology 57, 1932–3 (2001).