European Journal of Nuclear Medicine

, Volume 27, Issue 12, pp 1793–1799

Evaluation of the effect of high-energy proton irradiation treatment on meningiomas by means of 11C-L-methionine PET

  • O. Gudjonsson
  • E. Blomquist
  • A. Lilja
  • H. Ericson
  • M. Bergström
  • G. Nyberg
Original Article

DOI: 10.1007/s002590000335

Cite this article as:
Gudjonsson, O., Blomquist, E., Lilja, A. et al. Eur J Nucl Med (2000) 27: 1793. doi:10.1007/s002590000335

Abstract.

A remnant meningioma of WHO grade I that is located at the base of the skull and is treated with radiotherapy has to be followed up for at least 5–10 years to evaluate the treatment effect and detect recurrence. The tumour has to grow considerably to show detectable volume increase on computed tomography (CT) or magnetic resonance imaging (MRI). Owing to the location at the base of the skull, a small increase in tumour volume may be hazardous. It is thus important to find a method to evaluate treatment effects earlier and potentially detect those tumours that have a tendency to grow. Nineteen patients with intracranial meningiomas were given irradiation with the 180-MeV proton beam at the Svedberg Laboratory, Uppsala. The fractionation schedule used was in general a total dose of 24 Gy in four consecutive daily 6-Gy fractions. Serial 11C-L-methionine PET examinations were used to evaluate the effect of stereotactic proton beam treatment. The radioactivity uptake in the tumour was evaluated as the ratio to the uptake in normal brain tissue. The follow-up period thus far is 36 months. In 15 of the 19 patients, 11C-L-methionine uptake was reduced 36 months after irradiation compared with the pre-treatment uptake of the tracer. In the total patient group the average reduction was 19.4%. Our results reveal that proton beam irradiation of meningiomas had an inhibitory effect on the methionine uptake in the meningiomas, although tumour size remained unchanged. The combination of unchanged tumour morphology and a reduction in methionine uptake after irradiation suggests that 11C-L-methionine PET might enable earlier evaluation of the treatment effect than is possible with CT or MRI.

Meningioma 11C-L-methionine Positron emission tomography Stereotactic irradiation Proton beam therapy

Copyright information

© Springer-Verlag 2000

Authors and Affiliations

  • O. Gudjonsson
    • 1
  • E. Blomquist
    • 2
  • A. Lilja
    • 4
  • H. Ericson
    • 1
  • M. Bergström
    • 3
  • G. Nyberg
    • 1
  1. 1.Department of Neurosurgery, University Hospital, UppsalaSweden
  2. 2.Department of Oncology, University Hospital, UppsalaSweden
  3. 3.PET Centre, Uppsala UniversitySweden
  4. 4.Department of Neuroradiology, Karolinska Hospital, StockholmSweden
  5. 5.Correspondence to: Department of Neurosurgery, University Hospital, 751 85 UppsalaSweden