July 23, 2016 - 6:00 AM
VICTORIA - Canadian rock band the Tragically Hip begins what is being billed as its final tour after lead singer Gord Downie was diagnosed with a deadly brain cancer. Here are five things to know about the type of illness Downie has, a glioblastoma multiforme (GBM) brain tumour:
WHAT IS GLIOBLASTOMA? It's the most common and most aggressive cancerous-primary brain tumour (a tumour that starts in the brain). Glioblastoma tumours are made up of different cell types and are usually highly cancerous because the cells reproduce quickly and have a large network of blood vessels supporting them. Most of these tumours occur in the cerebral hemispheres, but can develop in other parts of the brain such as the corpus callosum, brain stem or spinal cord. Like many brain tumour types, the exact cause is not known, but increasingly research is pointing toward genetic mutations.
PREVALENCE OF GLIOBLASTOMA: The rate of glioblastoma is about two to three per 100,000 people in Canada, the United States and Europe. Sunnybrook Health Sciences Centre in Toronto says it treats around 250 patients with glioblastoma each year. This type of tumour is more common in older individuals and more common in men than women. Each case is unique, but average survival is less than one year, even with aggressive treatment.
SYMPTOMS: A patient's symptoms depend on the location of the tumour. Some common symptoms include headache, weakness, nausea, seizure, memory difficulties, personality changes and vomiting. Sometimes the tumour starts producing symptoms quickly, but on occasion there are no symptoms until it reaches a larger size.
TYPES OF GLIOBLASTOMA: The American Brain Tumor Association cites two types of glioblastomas. These include primary, or "de novo," and secondary. Primary tumours tend to form and make their presence known quickly. This is the most common form of glioblastoma, which is very aggressive. Secondary tumours have a longer, somewhat slower growth history, but are still very aggressive. They may begin as lower-grade tumours, which eventually become higher grade. They tend to be found in people 45 and younger, and represent about 10 per cent of glioblastomas.
TREATMENT: The first treatment step is surgery to remove as much tumour as possible. Surgery is almost always followed by radiation. Glioblastoma's capacity to wildly invade and infiltrate normal surrounding brain tissue makes complete resection impossible. After surgery, radiation therapy is used to kill leftover tumour cells and to try and prevent recurrence. Chemotherapy is often given at the same time as radiation and may be used to delay radiation in young children.
Source: Sunnybrook Health Sciences Centre; Brain Tumor Foundation of Canada; American Brain Tumor Association.
News from © The Canadian Press, 2016