ESTRO 2024 - Abstract Book

S946

Clinical - CNS

ESTRO 2024

agreement between the patient's perceived neurocognitive functions in the last seven days and the documented tests. Moreover 9/9 patients stated that any found problems (such as difficulty concentrating or remembering) significantly impacted their quality of life. Only in 1/9 cases the caregiver's perceptions of the patient's neurocognitive functions were discordant thought the patient's; in particular the caregiver had a worse perception of the neurocognitive patient's status. Evaluation at the end of concomitant radiochemotherapy was performed in 6/9 patients. In 2/6 patients a consensual worsening of the CDT and MMSE result was detected. In 2/6 patients there was a slight worsening of the result on the CDT compared with substantial stability on the MMSE. In the remaining 2/6 patients, there was stability of the results on both the clock test and the MMSE before and after the treatment. The next step will be the neurocognitive assessment three months after the end of radiochemotherapy.

Conclusion:

Cognitive functioning evaluation should be included among the standard clinical endpoints in treating adult neuro oncology patients. We think developing and validating an efficient and quick neurocognitive assessment tool could be helpful in clinical practice to establish neurocognitive function and the clock drawing test seems to be a sensitive and rapid screening tool.

Keywords: GBM, clock test, MMSE

2789

Digital Poster

First clinical experience of fractionated proton radiotherapy of schwannomas of the cranial nerves

Petra Mozes, Carola Lütgendorf-Caucig, Maciej Pelak, Birgit Flechl, Ulrike Mock, Leonie Brodbek, Eugen B. Hug

MedAustron, Ion Therapy Center, Wiener Neustadt, Austria

Purpose/Objective:

Schwannomas are benign nerve sheath tumors originating from the Schwann cells. Treatment of schwannomas include observation, surgery, stereotactic fractionated radiotherapy (SFRT) and radiosurgery (RS) [1]. Radiotherapy provides excellent 10-years local control rates of 92%. Loss of nerve function occurs somewhat earlier after RS (median 36 months, range 2,3-13,7 years) compared to FSRT (48 months, range 0-13,8 years) [2]. In this study we discuss early clinical outcome of cranial nerve schwannomas treated with fractionated proton radiotherapy (FPRT).

Material/Methods:

From November 2017 to August 2023 n=22 patients were treated with FPRT to a dose of 54 Gy (RBE)/ 27-30 fractions (5 fractions/week). The mean age was 50,5 years (range 24-80 years). 4/22 patient underwent biopsy and 9/22 had at least one partial resection prior to FPRT. Affected nerves were: n=9 n. vestibulocochlearis, n=5 n. facialis, n=2 n. trigeminus, n=2 n. glossopharyngeus, n=1 n. vagus, n=1 n. hypoglossus, n=1 n. abducens. The involvement of