The short answer to this broad question is No. One could argue that treatment for certain brain tumours could be started without knowing a histological diagnosis but this is definitely not the case for all brain tumours, especially if by starting treatment you mean surgical resection. I can imagine identifying a chemotherapy treatment based on histology post-surgery would be possible, however you must consider cases where surgical resection would become a more difficult choice if one did not know the tumour grade. Is it worth risking a difficult resection of a pilocytic astro in a tricky spot without knowing that its a pilocytic astro? You might be more keen to recommend surgical intervention based on tumour grade. I think the patient also deserves to know what the risk/benefit is depending on the tumour they have. Even though imaging technology has developed substantially, I don't think all treatments would be confidently called in all cases. Tumour histology is also important in determining whether focal and craniospinal radiation will be required.

The lack of biopsies for certain tumours and the belief that MRI findings are sufficient for diagnosis have hampered the development of treatments for certain brain tumours such as paediatric DIPG, for which surgery is not an option. Based on initial histological/CT findings in the 1980s it was determined that symptoms and radiological findings will be sufficient for diagnosis. Since that time, clinical trials for these patients were based on the assumption that because the histology of these tumours is most similar to adult GBM, similar treatment regiments will work. For many years there have been clinical trials with TMZ and other agents that had some positive effects in adults yet no chemotherapy/XRT combination has yielded any improvement in survival compared to radiation alone. Why?...because we have ignored the histology and underlying biology of these tumours for many years. In Europe and especially in France, biopsy is again becoming a standard for these patients and they are being more frequently performed in North America as well. I think molecular pathology will be the way of determining treatments for brain tumours in the future as we develop more targeted treatments. We already see the clinical relevance of molecular profiling in medullo and other brain tumours. Whether histology at biopsy will play a different role in the future is yet to be seen, but for sure it is still too early to discount it today.

Actually there is no a diagnostic technique that will replace a brain biopsy. Moreover, treatment of tumor pathology should make based on a real knowledge of the injury.

Most diagnostic methods known until now are complementary, but neither replaces the brain biopsy.

There are some selected cases in which we can start treatment without biopsy, namely secreting germ cell tumours, and some optic gliomas in context of NF I; I am agree with the statements about Pediatric DIPG