Clinical Trial: Multisession Radiosurgery for Optic Nerve Sheath Meningiomas

Study Status: Recruiting
Recruit Status: Recruiting
Study Type: Interventional

Official Title: Observational Study on Multisession Radiosurgery for Optic Nerve Sheath Meningiomas

Brief Summary:

Traditional treatment options for optic nerve sheath meningiomas (ONSM) include observation, surgery and radiotherapy, but to date none of these has become the clear treatment of choice.

The role of the radiotherapy remained uncertain because of the concern about radiation related optic neuropathy In the recent past two large series of patients treated with a fractionated stereotactic radiotherapy confirmed these positive experiences in tumour control and greatly reduced the concern about the treatment related toxicity.

Under the light of successful meningiomas treatment, radiosurgery, had proposed as a treatment option. Single session, high conformality, frame based radiosurgery systems are seldom if ever proposed as ONSMs treatment due to the known dose tolerance of the optic nerve.

The first experience in ONSMs treatment with multisession radiosurgery treatment was quite promising.

The aim of the present study is to prospectively evaluate the efficacy and safety of multisession radiosurgery in ONSMs treatment.

In order to evaluate multisession radiosurgery 50 patients will be enrolled in the present study.

All patients will be treated by using multisession radiosurgery, with 5 fractions of 5 Gy each to a total dose of 25 Gy prescribed to the 75-85% isodose line. Patients were evaluated both for tumor growth control and visual function.

Detailed Summary:

Introduction Optic Nerve Sheath Meningiomas (ONSMs) are rare tumours. They represent approximately the 2% of all orbital tumours, 1-2% of intracranial meningiomas and one third of the optic nerve lesions (23, 32, 42, 43). Usually these tumour are monolateral but 5% have a bilateral development (33) On the base of the growth pattern these tumours can be classified in primary and secondary forms. The former type arise from the arachnoid cap cell of the fibrous dural capsule of the optic nerve and they usually growth circumferentially along the nerve. Primary ONSMs can be further subdivided in orbital and intracanalicular forms.

Secondary ONSMs usually arise from the sphenoid ridge or the tuberculum sellae and subsequently spread into the optic canal and the orbit (14, 42).

Often the pathological studies show meningotheliomatous or transitional histology.

Middle aged woman are the most often affected (4, 36, 44). The most frequent presentation symptom is a visual loss, both in acuity or visual field. This is nearly an expression of an optic nerve direct compression and of the vascular rearrangement.

Optic nerve atrophy is common. Optociliary shunts are a late and rare sign but they are the direct expression of compressive optic neuropathy and it can be pathognomonic for the diagnosis of ONSM (35, 43).

Traditionally treatment options include observation, surgery and radiotherapy but, until now, any of these had assumed as the treatment of choice.

Nevertheless, the development of the new technology improved the interest in radiotherapy application.

Conservative treatment can be cons
Sponsor: Fondazione I.R.C.C.S. Istituto Neurologico Carlo Besta

Current Primary Outcome: visual function outcome [ Time Frame: 5 year ]

Original Primary Outcome: Same as current

Current Secondary Outcome:

• PFS - progression free survival [ Time Frame: 5 year ]
  Partial response: tumor reduction more than 20%. Progression disease: any increased
• toxicity [ Time Frame: 5 year ]
  according to NCI CTCAE v3.0

Original Secondary Outcome: Same as current

Information By: Fondazione I.R.C.C.S. Istituto Neurologico Carlo Besta

Dates:
Date Received: October 15, 2015
Date Started: January 2011
Date Completion: December 2025
Last Updated: November 2, 2015
Last Verified: November 2015