A Nicolato1. 1. Department of Neurosurgery, University Hospital, Verona, Italy.
Abstract
AIM: The purpose of this study is to prospectively investigate the prognostic role of somatostatin receptor scintigraphy (SRS) using an 111Indium-labelled somatostatin analogue, Octreotide, in skull base meningiomas (SBMs) treated with gamma knife (GK) radiosurgery. METHODS: From December 1997 to March 2000, SRS was performed both before and within 1 year of radiosurgery on 12 patients. Semi-quantitative data were calculated as SRS index; the index decrease was arbitrarily considered significant above 10%. A potential correlation between the decrease in post/pre-GK SRS index and radiosurgical outcome was evaluated. RESULTS: The follow-up period was at least 30 months in the whole series (median, 43 months). In all 12 patients, the pre-GK SRS index was always >1, averaging 3.73+/-2.9. A decrease in the post-GK average SRS index (2.35+/-1.5) was observed. The difference between the pre- and post-GK average values was statistically significant (p<0.03). At the 1st high-resolution magnetic resonance imaging (MRI) follow-up within 1 year of GK, there was no tumor shrinkage in any of the 12 patients of our series. A post/pre-GK SRS index decrease >10% was observed in 9 patients and <10% in 3. Delayed MRI follow-up documented tumor reduction in all 9 cases having an 111In uptake decrease >10%, with stable imaging in the others (p=0.00024). CONCLUSION: Our preliminary findings suggest a prognostic correlation between a decrease in concentration of somatostatin receptors on meningioma cells within 1 year of radiosurgery and delayed meningioma shrinkage.
AIM: The purpose of this study is to prospectively investigate the prognostic role of somatostatin receptor scintigraphy (SRS) using an 111Indium-labelled somatostatin analogue, Octreotide, in skull base meningiomas (SBMs) treated with gamma knife (GK) radiosurgery. METHODS: From December 1997 to March 2000, SRS was performed both before and within 1 year of radiosurgery on 12 patients. Semi-quantitative data were calculated as SRS index; the index decrease was arbitrarily considered significant above 10%. A potential correlation between the decrease in post/pre-GK SRS index and radiosurgical outcome was evaluated. RESULTS: The follow-up period was at least 30 months in the whole series (median, 43 months). In all 12 patients, the pre-GK SRS index was always >1, averaging 3.73+/-2.9. A decrease in the post-GK average SRS index (2.35+/-1.5) was observed. The difference between the pre- and post-GK average values was statistically significant (p<0.03). At the 1st high-resolution magnetic resonance imaging (MRI) follow-up within 1 year of GK, there was no tumor shrinkage in any of the 12 patients of our series. A post/pre-GK SRS index decrease >10% was observed in 9 patients and <10% in 3. Delayed MRI follow-up documented tumor reduction in all 9 cases having an 111In uptake decrease >10%, with stable imaging in the others (p=0.00024). CONCLUSION: Our preliminary findings suggest a prognostic correlation between a decrease in concentration of somatostatin receptors on meningioma cells within 1 year of radiosurgery and delayed meningioma shrinkage.
Authors: Henry Ruiz-Garcia; Daniel M Trifiletti; Nasser Mohammed; Yi-Chieh Hung; Zhiyuan Xu; Tomas Chytka; Roman Liscak; Manjul Tripathi; David Arsanious; Christopher P Cifarelli; Marco Perez Caceres; David Mathieu; Herwin Speckter; Gautam U Mehta; Gregory P Lekovic; Jason P Sheehan Journal: J Neurol Surg B Skull Base Date: 2021-01-19