Thema: News: Stereotactic radiotherapy for malignant meningiomas?
News: Stereotactic radiotherapy for malignant meningiomas?
Tom[a]
28.05.2002 11:11:12
Is stereotactic radiotherapy adequate treatment for atypical and malignant meningiomas?
Simon S Lo, Kwan H Cho, Walter A Hall, Wilson L Hernandez, Kimberly K McCollow, Judy Unger, University of Minnesota, Minneapolis, MN.
Objective: To evaluate whether stereotactic radiotherapy alone is an adequate treatment for recurrent atypical and malignant meningiomas.
Method: From 1992 to 2000, 10 patients with 16 recurrent atypical (A) or malignant (M) meningiomas (5 A and 11 M) were treated with stereotactic radiosurgery (SRS) or fractionated stereotactic radiotherapy (FSRT). Patients with tumors greater than 4 cm or closer than 5 mm to the optic apparatus were chosen for FSRT. The SRS doses ranged from 1200 cGy at 50% to 4500 cGy at 50% and the FSRT doses ranged from 4500 cGy at 85% in 25 fractions to 5000 cGy at 90% in 20 fractions. A 2 mm margin was placed around the target as defined on the computerized tomography. The median follow-up ranged from 3 months to 66 months. Five patients had external beam radiation therapy to the same areas previously. All patients had radiologic follow-up with magnetic resonance imaging.
Result: The 5-year actuarial tumor control was 31%. Five (50%) of the 10 patients developed recurrence. Two (40%) of the five patients who developed recurrence had disease recurring in the area outside the treated areas with no evidence of local recurrence. The time to recurrence ranged from 3 to 66 months. Three patients recurred after more than 3 years. The crude tumor shrinkage rate was 19%. The crude local progression rate was 31%.
Result: Our analysis showed that stereotactic therapy alone for the treatment of atypical and malignant was associated with poor tumor control. The suboptimal local control and the propensity of A and M for regional recurrence warrant the investigation of more aggressive and innovative therapies. The potential long latency for tumor recurrence underscores the importance of long-term follow-up of these patients.
Simon S Lo, Kwan H Cho, Walter A Hall, Wilson L Hernandez, Kimberly K McCollow, Judy Unger, University of Minnesota, Minneapolis, MN.
Objective: To evaluate whether stereotactic radiotherapy alone is an adequate treatment for recurrent atypical and malignant meningiomas.
Method: From 1992 to 2000, 10 patients with 16 recurrent atypical (A) or malignant (M) meningiomas (5 A and 11 M) were treated with stereotactic radiosurgery (SRS) or fractionated stereotactic radiotherapy (FSRT). Patients with tumors greater than 4 cm or closer than 5 mm to the optic apparatus were chosen for FSRT. The SRS doses ranged from 1200 cGy at 50% to 4500 cGy at 50% and the FSRT doses ranged from 4500 cGy at 85% in 25 fractions to 5000 cGy at 90% in 20 fractions. A 2 mm margin was placed around the target as defined on the computerized tomography. The median follow-up ranged from 3 months to 66 months. Five patients had external beam radiation therapy to the same areas previously. All patients had radiologic follow-up with magnetic resonance imaging.
Result: The 5-year actuarial tumor control was 31%. Five (50%) of the 10 patients developed recurrence. Two (40%) of the five patients who developed recurrence had disease recurring in the area outside the treated areas with no evidence of local recurrence. The time to recurrence ranged from 3 to 66 months. Three patients recurred after more than 3 years. The crude tumor shrinkage rate was 19%. The crude local progression rate was 31%.
Result: Our analysis showed that stereotactic therapy alone for the treatment of atypical and malignant was associated with poor tumor control. The suboptimal local control and the propensity of A and M for regional recurrence warrant the investigation of more aggressive and innovative therapies. The potential long latency for tumor recurrence underscores the importance of long-term follow-up of these patients.
Tom[a]
