AUTHOR=Huang Yong , Ding Haixia , Luo Min , Li Zhiqiang , Li Sirui , Xie Conghua , Zhong Yahua 

TITLE=A new approach to delineating clinical target volume for radiotherapy of glioblastoma: A phase II trial

JOURNAL=Frontiers in Oncology

VOLUME=Volume 12 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/oncology/articles/10.3389/fonc.2022.931436

DOI=10.3389/fonc.2022.931436

ISSN=2234-943X

ABSTRACT=Purpose:
No consensus has currently been made regarding the optimal radiation volume for radiotherapy of glioblastoma. Here, we have proposed a new delineation approach to delineating clinical target volume based on the relationship between the growth patterns of glioblastoma and neural pathways. Its safety and efficacy were evaluated in a phase II clinical trial.
Methods:
A total of 69 patients with histologically confirmed glioblastoma were enrolled. All patients underwent tumor resection, followed by focal radiotherapy and concomitant temozolomide (TMZ), then received 6 cycles of adjuvant TMZ. The gross tumor volume (GTV) was defined as the surgical resection cavity plus any residual enhancing tumor on contrast enhanced T1 weighted MRI. The clinical target volume (CTV) was delineated through our new approach.
Results:
The median recurrence-free survival (RFS) and overall survival (OS) were 11.4 months and 18.2 months,which were better than the previous reports. Relapse was found in 47 patients, of whom 41 patients (87.2%) were failed in central, 2 patients (4.3%) were failed in field and 4 patients (8.5%) were failed in distance, no marginal recurrence was found. Our regimen showed a trend of lower rates of marginal recurrence and the brain volume of high-dose radiation fields in our regimen was similar with that of EORTC (p=0.257).
Conclusions:
We have proposed a novel method for the delineation of clinical target volume by referencing the nerve fiber bundles for radiotherapy of glioblastoma. The results of the present phase II clinical trial suggested that this approach may be feasible and effective.