Aggressive brain cancers and precision medicine- trends and advances

May 19, 2017

Although brain cancers are a rare occurrence in India, with a mere two or three reported cases for every 1,00,000 patient population, it is still a cause for concern. One of the most common assumptions was that infections and lifestyle habits, mobile phones were linked to be one of the causes of brain cancers. However, studies show that this is not the case and that primary brain tumours arise from hereditary disorders and spontaneous genetic mutations. The most common malignancy in the brain is a spread from cancers in other parts of the body like the breast, stomach, intestine. Gliomas are one of the most common primary “indigenous” tumours that occur in the brain and are made up of glial cells. Gliomas make up close to 30 per cent of all brain tumours, are graded from I to IV with a higher grade indicating the most aggressive tumour. This aggressive tumour termed glioblastoma multiformae represents 80 per cent of all malignant tumours. There are three common types of active gliomas- astrocytomas, oligodendrogliomas and ependymomas. Astrocytomas are caused by the mutation of astrocytes in the brain cells and result for almost 50 per cent of all brain tumours.

Not all brain tumours are cancers. Once a glioma has been identified, treating them depends on the location, grade of malignancy and the cell type. Surgery is perfomed to remove as much tumour as possible and to establish a pathological grade; with radiation therapy and chemotherapy (temozolamide) reserved for malignant tumours. More recently though, studies have shown that angiogenic blockers like bevacizumab, along with second-line chemotherapy have been beneficial in treating high-grade recurrent glioblastoma.

Researchers have also developed models which will help oncologists understand the influence of driver mutations (mutations which promote cancer development) have on the initiation and development of gliomas. These models suggested that the simultaneous activation of certain molecular pathways a in a cell triggered initiation and produced dense low grade gliomas which progressed quickly to glioblastoma multiforme.

Understanding that brain cancers survival rates are low with a majority of patients not crossing the five year period from the time of diagnosis, researchers and oncologists are continuously identifying new treatment methods. As technology advances, treatment methods are keeping pace with newer radiology and chemotherapy methods being developed. Oncologists are also experimenting with new techniques for surgeries. Reputed institutes like the Indian Institute of Science in Bangalore, Tata Memorial Centre in Bombay, Indian Institute of Technology, Chennai among others are also making significant progress in developing new methods of treating brain cancers like molecular and gene therapy. 

In spite of so many advancements in treatment, there is still no permanent solution to brain cancers, though a patient’s life can be prolonged for at least a few months. As an industry though, researchers and oncologists are taking advantage of this information and working to develop immune cells with different tumour targeting proteins. These cells will also be specific to different cancers and are the future of precision medicine being applied to control cancer.