Malignant glioma in Hong Kong Chinese

Abstract

An analysis of a registry of brain and central nervous system (CNS) tumor patients in Hong Kong comprising of data from both public and private neurosurgical practices (with approximately 98% patients of Chinese origin), suggested geographical or racial variations in disease incidence. The annual incidence of malignant gliomas was 1 case per 100,000 per year for patients of Chinese origin living in Hong Kong; considerably lower than the US incidence of 5.97 cases per 100,000 per year. The most frequently observed glioma subtype was glioblastoma multiforme (GBM, WHO Grade IV), constituting 42% of all glioma cases and 5% of all brain tumor cases in Hong Kong. High--‐‑grade malignant glioma (HGG) was most prevalent in patients aged between 45 and 64 years.

5-ALA-based fluorescence-guided surgery was found to be feasible and safe to adopt in the treatment of 9 local WHO Grade III & IV gliomas patients with positive O’ methylguanine-DNA methyltransferase (MGMT) methylation status. This surgical adjunct helped to achieve a satisfactory extent of removal, and was useful in preserving neurological functions during surgery in eloquent areas when used together with intraoperative functional mapping techniques.

Recent advances in glioma molecular biology have played an important role not only in pathological diagnoses and classification, but also in the development of more effective targeted molecular therapies. Bevacizumab has been documented to be well tolerated in Asian patients. It was approved for use as a single-agent in patients with relapsed GBM by the Department of Health of Hong Kong in September 2009. However, known complications such as cerebral hemorrhage and wound dehiscence are of particular concern to neurosurgeons treating patients who have received bevacizumab either before or after surgery. Salvage therapies with either single agent bevacizumab or bevacizumab plus irinotecan appeared to be effective treatment options in Hong Kong patients with recurrent high-grade malignant glioma (HGG), with a good associated 6-month progression-free survival (PFS) rate which was comparable to previously published overseas data in this disease type in the overall population. No difficulty in achieving hemostasis was reported and no cases of post-operative cerebral hemorrhaging occurred; suggesting the potential for more aggressive treatment strategies for HGG.