Page 78 - Read Online

Bellu et al. J Cancer Metastasis Treat 2021;7:29 https://dx.doi.org/10.20517/2394-4722.2021.89 Page 7 of 8

It could be an interesting perspective for future insights to investigate novel and more specific radiological
techniques, such as positron emission tomography (PET-CT) or PET-MRI with amino acid tracers such as
11
18 F-fluoro-ethyl-l-tyrosine (FET) and C-methyl-L-methionine (MET), which can probably better
[15]
distinguish more aggressive tumor areas .

The reason a similar OS was obtained in patients with oligodendrogliomas and astrocytomas is not clear.
Indeed, oligodendrogliomas should have a longer OS than astrocytoma. It is likely that our result could be
due to the small number of patients analyzed in this study.

It is also interesting to note that no difference was found between the type of treatment at diagnosis;
however, our results could be due to the small population analyzed or the retrospective design of this study.
Indeed, the type of treatment was unbalanced among the patients: 67% of them received chemotherapy
alone, as the choice of treatment was at the physician’s discretion, which could have influenced clinical
outcomes. This is still a much debated topic, with multiple studies published with different results; in most
of them, CT and RT seem to have the same results [16,17] , so it is reasonable to recommend CT upfront with
the aim of limiting neurotoxicity induced by RT . As regards the chemotherapy regime, TMZ resulted safer
[5]
[18]
than PCV with similar results in terms of PFS and OS ; however, PCV was the only schedule analyzed in a
phase 3 randomized study in patients with anaplastic oligodendroglial tumors. Therefore, it could be correct
to use temozolomide in patients with astrocytoma and PCV for an oligodendroglial tumor. However, it
appears clear that it is absolutely important to identify predictive factors and focus the therapy on specific
targets to obtain a better outcome with minimal toxicity. The recent randomized, phase 3 study (RTOG
9802) analyzing high-risk low-grade glioma patients treated with RT + PCV vs. RT alone demonstrated a
longer OS for the combination regimen . A subsequent genomic analysis showed that IDH-mutant
[20]
[19]
high-risk LGG, regardless of the 1p19q codeletion status, received benefits from the administration of
chemotherapy; conversely, in our population, we showed no significant difference between combination or
single treatment, although multivariate analysis was not performed due to the small number of patients. In
conclusion, based on our results, GC patients with a good performance status, mutated IDH, and/or
methylated MGMT should be treated with combination therapy, where possible. In the case of advanced
disease where RT cannot be performed, CT should be evaluated in selected patients with molecular
alterations and second-line therapy could be recommended for patients with a good clinical condition.

DECLARATIONS
Authors’ contributions
Contributed to patient and data collection: Bellu L, Caccese M, Cerretti C, Berti F, Busato F, Parisi A,
Padovan M, Zagonel V, Lombardi G
Wrote the paper: Bellu L, Lombardi G

Availability of data and materials
All the data are recorded at Veneto Institute of Oncology. No public database exists.

Financial support and sponsorship
Not applicable.

Conflicts of interest
All authors declare that there are no conflicts of interest.