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where 17.5-34.5% of patients had received complete tumor maintained at micromolar levels for days, including brain.
resection prior to study entry. [2,35] All patients in our study This catabolite was recently shown to be able to inhibit
had residual disease after surgery, while 67% of the patients thymidylate synthase. This inhibition, leading to an
[42]
were biopsied-only. A subgroup analysis of TMZ plus accumulation of deoxyuridine triphosphate (dUTP), might
radiotherapy showed that the 93 patients who underwent be basis for an additional radiosensitizing effect. Hence a
[9]
only biopsy had no significant improvement in median dual radiosensitization might be achieved in glioma.
overall survival. [2]
In conclusion, this study shows that fixed dose rate infusion
Although PFS was the secondary objective in the present of gemcitabine given before radiotherapy is clinically
study, our results are not likely to be influenced by sequential effective as a radiosensitizer for newly diagnosed GBM.
temozolomide as it was only given after progression of Gemcitabine has a better cost effectiveness compared to
the patients. In contrast, OS may be affected by the TMZ the financial cost temozolomide. Further investigation of
administered at disease progression. In another study, chemo-radiotherapy is needed and a Phase 3 trial with a
[30]
this might not have been the case. higher number of patients will be initiated, to determine
whether the gemcitabine radiosensitizing effect can be
The combination of gemcitabine plus radiotherapy was achieved irrespective of the methylation status of the
well tolerated. No treatment-related grade 4 toxicities were MGMT promoter. [30]
observed, while there were only 6 cases of grade 3 adverse
events, including 5 patients with hematological toxicity Financial support and sponsorship
and one with hypertransaminasemia .This was in line with This study was supported and coordinated by the Egyptian
toxicity reported for gemcitabine with RTH in high grade ministry of higher education grant, Egypt.
glioma patients with weekly schedule. On the whole,
[30]
the treatment-related morbidity did not differ significantly Conflicts of interest
from that observed with nitrosourea or temozolomide given There are no conflicts of interest.
concurrently with radiotherapy. [2,34,35]
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Journal of Cancer Metastasis and Treatment ¦ Volume 2 ¦ May 18, 2016 ¦