ESTRO 2024 - Abstract Book

S845

Clinical - CNS

ESTRO 2024

mean TC for whole brain was 0.95±0.16, mean CN was 0.92±0.16 and mean HI was 0.1±0.04. The mean PITV and MDPD was 0.94±0.18 and 1.1±0.15 respectively. The mean volume of hippocampus was 4.54cc ±1.43. The minimum dose covering 100% hippocampus volume was 5.2Gy. Maximum dose to hippocampus was 14.4Gy while the mean dose was 7.4Gy. MMSE scores significantly improved from baseline after WBRT but there was no strong association with hippocampus dosage till 4 months post WBRT (p<0.01). HVLT-R parameters demonstrated improvement from baseline values and post 4 months of WBRT, had significant negative association with hippocampus dosimetry. Immediate recall had statistically significant negative correlations with minimum and maximum hippocampal dosage after 4months post RT. Immediate recognition and delayed recall showed strong negative association with mean dosage in addition to minimum and maximum hippocampus dosage. FACT-BR scores showed a significant increase from baseline to completion and had strong positive correlation to MMSE scores and HVLT-R parameters. The strength of association was persistent from baseline to 6months post RT.

Conclusion:

We conclude that helical tomotherapy is capable of delivering an highly conformal and homogenous HS-WBRT plan while achieving dose constraints of hippocampus in a reasonable treatment time. Also, anatomical avoidance of hippocampus contribute to preservation of neurocognition and maintain quality of life. Since, deleterious effect of hippocampus irradiation on neurocognitive function is more pronounced after 4months of HS-WBRT, longer administration of NCF test batteries is desirable. The feasibility of HS-WBRT predicts successful sparing of hippocampus without affecting target coverage even in definitive radiotherapy and should be considered for treatment of curable brain tumors, where the advantage of hippocampal sparing will be more profound.

Keywords: Hippocampal sparing, WBRT, Tomotherapy

1572

Digital Poster

A study comparing temozolomide (TMZ) before CTRT versus standard treatment in high grade glioma

Shubha De Sarkar 1 , Aloke Ghosh Dastidar 2

1 MJN Medical College, Radiotherapy, Cooch Behar, India. 2 IPGME&R and SSKMH, Radiotherapy, Kolkata, India

Purpose/Objective:

In developing countries, often, there is delay between surgery and radiation therapy due lack of adequate radiation oncology set ups. In this study I have tried to find out the advantages and disadvantages of postoperative TMZ before concomitant chemo-radiation in comparison to standard of care.