Inclusion Criteria

Inclusion Criteria

Patients meeting all of the following criteria will be considered for admission to the
trial:

- Histologically or imaging confirmed skull base meningioma

- macroscopic tumor - Simpson Grade 4 or 5

- age ≥ 18 years of age

- Karnofsky Performance Score >=60

- For women with childbearing potential, (and men) adequate contraception (sexual
abstinence, estrogen- or gestagen containing contraceptive medication etc.)

- Female participants: No pregnancy present (pregnancy test required)

- Ability of subject to understand character and individual consequences of the
clinical trial

- Written informed consent (must be available before enrolment in the trial)

Exclusion criteria:

Patients presenting with any of the following criteria will not be included in the trial:

- refusal of the patients to take part in the study

- previous radiotherapy of the brain

- histologically confirmed atypical or anaplastic meningioma

- optic nerve sheath meningioma (ONSM)

- Patients who have not yet recovered from acute toxicities of prior therapies

- Known carcinoma < 5 years ago (excluding Carcinoma in situ of the cervix, basal cell
carcinoma, squamous cell carcinoma of the skin) requiring immediate treatment
interfering with study therapy

- Pregnant or lactating women

- Participation in another clinical study or observation period of competing trials,
respectively.