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increase of adjuvant therapy. [3-5] mutation only group with 32 patients and triple negative
group with 80 patients. This data shows that almost 75% of
Neuroimaging has been playing an important role in the patients with GBM have only TERT mutation and have
neurosurgery in the last century and technology has come a correlation with aggressive behavior type of gliomas.
to provide details in neuroanatomy, neurological function, Also, patients with Grade II-III with TERT mutation only
metabolic and metabolism, which augments the ability to (59 patients), had an aggressive course and were associated
increase the extent of resection (EOR) while simultaneously, with poor survival, which suggest the need of early adjuvant
minimizes the risk of damage in eloquent brain. [1] therapies and special follow-up. Also only IDH mutation,
was associated with lowest age of diagnosis (37 years) and
Increasing evidences show the importance of GTR the highest rates were found in the only TERT mutation
for glioblastoma multiforme (GBM’s) and adjuvant group (59 years), between all the gliomas. This study opens
radiochemotherapy and demonstrate a 2-8 months survival for further research between the association of TERTp and
benefit in patients with GTR compared to sub-total other previously discussed mutations. [8]
resection. [3-5] Nevertheless, after a first impact, the focus
has changed from just increasing the EOR, to increase the The genetic studies and imaging findings have become
quality of life and safe resection; the tumor relationship allies in the understanding of tumor behavior; nevertheless
critical anatomic structures and eloquent areas have become have also pointed questions on the efficiency of the surgical
the center of the discussion. techniques to improve patient prognosis and the natural
history of these tumors.
Nowadays, molecular genetics came to open further
discussions about tumor behavior, such as isocitrate METHODS
dehydrogenase mutations (IDH) 1/2, 1p19q codeletion,
PTEN deletions, MGMT mutation, telomerase reverse A literature search of the Ovid Medline and PubMed
transciptase (TERTp) mutation, EGFR and TP53. [6-8] The databases for the period January 1980 to September 2015
IDH 1 and 2, were first described in GBM’s, nevertheless was conducted using the following key words: brain tumor,
further research showed that it was more expressive in grade borders, technology, neuronavigation, intra-operative,
II-III diffuse gliomas (about 70%). IDH 1/2 mutations are fluorescein, novel. Main novel technologies were selected
important biomarkers for diffuse gliomas, because they by their relevance and were analyzed by categories.
behave less aggressively and a better prognosis, than other
IDH mutations (IDH wild-types), with a positive predictive RESULTS
value (PPV) for better progression-free survival and overall
survival. The 1p/19q codeletion is found in almost 70% Neurosurgery has rapidly changed in the past years due
[6]
of histologically oligodendrogliomas, thus have an indolent to new technologies and new different possible surgical
progression and might be the molecular defi nition of approaches. These changes have modified neurosurgical
oligodendroglial lineage. Also, these low-grade gliomas concepts, from an aggressive vision to a safe EOR with
(LGG) tend to respond well for chemotherapy, thus have good function. Since the beginning of the microsurgical
better prognosis. The MGMT is an enzyme, which repairs era, the surgical planning has improved from an anatomy-
the DNA and interferes in temozolamide effect. Mutations planned surgery to an optimal non-visible tumor borders
in the MGMT have been correlated with improved resection. [1,2]
prognosis and improved survival rate. [6,7] On the other hand
the ATRX/TP53 mutations might be the objective genetical Several technologies were introduced in the intra-operative
markers of the artrocytic lineage. [6,7] field such as functional monitoring with cortical and sub-
cortical mapping, imaging technologies as neuronavigation,
In GBM’s the most common aberrations are found in the intra-operative magnetic resonance imaging (iMRI),
chromosomes 7 and 10, where the PTEN and EGFR are intraoperative ultrassound (iUS), chemical biomarkers as
located. Aberrations on the PTEN and EGFR amplifications 5-aminolevulinic acid (5-ALA), and sodium fluorescence. [2]
are found in 80% and 30-40%, respectively, both of
them strongly related to poor prognosis and aggressive Some of these advances were possible not only for the
progression, which reinforces the idea that these tumors technology, but also due to anesthetic advances and better
with PTEN and/or EGFR amplifications are IDH-wild neurofunctional knowledge. [9,10]
type tumors. [6,7] Finally, studies points for the association
of promoter region of the TERTp mutation and poor Nevertheless, even with the standard care in neurosurgery,
prognosis. A recent research was published comparing the the 2-year survival rate in GBM’s still is about 38.4% and
[8]
TERTp mutation, 1p19q codeletion and IDH mutation in the 5-year rate is below 5%. [11-13] Also, past reports have
Grade II-III and GBM’s with interesting findings. TERTp shown that even with hemispherectomies, patients could
[8]
mutation only, was found in 347 patients with GBM’s, not be cured. [14,15] Even though, the surgical technology has
compared to the TERT and IDH group with 11 patients, IDH improved the past years, there are no consistent evidences

Journal of Cancer Metastasis and Treatment ¦ Volume 2 ¦ March 11, 2016 ¦ 71