PO-0635: Can psychological support during RT improve distress, mood or quality of life in CNS tumor patients?
Bildiriler > Özet Bildiri
Yazarlar: L. Dinapoli, S. Chiesa, N. Dinapoli, F. Beghella Bartoli, S. Bracci, M. Massaccesi, A. Tenore, A. Pesce, V. Valentini, M. Balducci
Radiotherapy and Oncology, , , Uluslararası, Özet Bildiri, Wos, cilt 123, ss S332-S333
DOI: 10.1016/s0167-8140(17)31072-1
Özet
Purpose or Objective Subventricular zone (SVZ) is a paired brain structure situated throughout the lateral walls of the lateral ventricles, a known site of neurogenesis and self-renewing neurons in the adult brain.Some current theories propose that brain tumour stem cells originating from subventricular zone (SVZ) play a role in progression of high-grade gliomas.Since almost all glioblastomas progress locally despite aggressive surgery and radiotherapy, recur within the high-dose irradiation volume in most cases, the theory of tumor cell migration from SVZ is interesting to explore.Irradiation of SVZ supposed to kill brain tumor stem cells which may alter tumour progression and survival.The purpose of this study is to evaluate the impact of the radiation dose to SVZ on progression rates and overall survival in glioblastoma. Material and MethodsStudy population consisted of 80 glioblastoma patients (23 females, 57 males) with a median age of 55.5 (21-75) who were treated from January 2012 to December 2014.All patients underwent surgery followed by adjuvant radiotherapy (60 Gy/30 fractions) and concomitant / adjuvant temozolomid.Bilateral SVZ were contoured on MRI images and registered to planning CT slices.Target volumes and organs at risk were also contoured.Conformal radiotherapy with 3-4 fields or IMRT with 1-2 volumetric arcs were used for planning.Median doses for ipsilateral, contralateral and bilateral SVZ were recorded and relations with progression and survival were analyzed using two threshold values at 40 Gy and 50 Gy.Analyses were performed after a median follow-up of 13 months. ResultsMedian progression free survival (PFS) was 10 months (2-36) and overall survival (OS) was 12 months (3-48).The unfavorable prognostic factors affecting PFS were tumor extending to ventricles (p<0.01),ipsilateral SVZ doses >50 Gy (p<0.05), and contralateral SVZ doses >50 Gy (p<0.05).The unfavorable prognostic factors affecting OS were tumor extending to ventricles (p<0.001),contralateral SVZ doses >40 Gy (p<0.05) and bilateral SVZ doses >40 Gy (p<0.05).In multivariate analysis of prognostic factors, tumor extending to ventricles was the only unfavorable factor for both PFS (p<0.001) and OS (p<0.001).Conclusion PFS and OS were shorter in the patients in whom tumor was extending to ventricles and in those where SVZ received at least 40-50 Gy.The data of this study is supports the previous studies showing an inverse correlation between irradiation of SVZ and prognosis.With the present data we can only speculate that those tumors extending deep into the lateral ventricles likely to be larger in size, closer to nearby sensitive structures, and not amenable to total resection.Radiation volumes should cover some parts of SVZ and lateral ventricles to give the prescribed dose to in those unfavorable tumors, which may explain the inverse correlation with SVZ irradiation and survival.Further research is required to clarify the role of brain tumor stem cells locates at SVZ in the prognosis of high-grade gliomas.