Anterior skull base meningiomas are surgically accessible lesions, whose treatment of choice is the surgical resection. Nevertheless, there are a group of complex tumors, such as those attached to or encasing the optic apparatus and/or neurovascular structures in which total resection cannot be safely achieved. Nonetheless, when a meningioma is subtotally resected, progression rates average 60 % at 10 years. The use of ionizing radiation is an effective strategy to treat those tumors. Currently available advanced radio-oncology techniques, including fractionated stereotactic radiotherapy (FSRT), intensity-modulated radiotherapy (IMRT), and stereotactic radiosurgery (SRS) allow for a steep dose gradient, meaning a favorable dose distribution on target and surrounding critical structures. Particularly, SRS has progressively emerged as the first-line treatment for both adjuvant treatment of residual tumors and an effective primary treatment of selected meningiomas. Radiosurgery for benign meningiomas achieves satisfactory results with local control rates that could rival those of surgical resection. Currently, 5-year progression- free survival averages 95 % and the 10-year progression-free survival reaches 85–90 % in most series. Radiosurgery is virtually noninvasive, but it does carry a risk of radiation-induced complications. The main issue, in such tumors, concerns the proximity of cranial nerves, including optic nerves and chiasm, that are extremely sensitive to radioinduced complications. Hypofractionated radiosurgery has provided interesting results with very limited risks of optic neuropathy, even though longer-term results are still necessary to identify the best dose/fractionation schemes.
Radiotherapy and Radiosurgery
Conti, Alfredo;
2016
Abstract
Anterior skull base meningiomas are surgically accessible lesions, whose treatment of choice is the surgical resection. Nevertheless, there are a group of complex tumors, such as those attached to or encasing the optic apparatus and/or neurovascular structures in which total resection cannot be safely achieved. Nonetheless, when a meningioma is subtotally resected, progression rates average 60 % at 10 years. The use of ionizing radiation is an effective strategy to treat those tumors. Currently available advanced radio-oncology techniques, including fractionated stereotactic radiotherapy (FSRT), intensity-modulated radiotherapy (IMRT), and stereotactic radiosurgery (SRS) allow for a steep dose gradient, meaning a favorable dose distribution on target and surrounding critical structures. Particularly, SRS has progressively emerged as the first-line treatment for both adjuvant treatment of residual tumors and an effective primary treatment of selected meningiomas. Radiosurgery for benign meningiomas achieves satisfactory results with local control rates that could rival those of surgical resection. Currently, 5-year progression- free survival averages 95 % and the 10-year progression-free survival reaches 85–90 % in most series. Radiosurgery is virtually noninvasive, but it does carry a risk of radiation-induced complications. The main issue, in such tumors, concerns the proximity of cranial nerves, including optic nerves and chiasm, that are extremely sensitive to radioinduced complications. Hypofractionated radiosurgery has provided interesting results with very limited risks of optic neuropathy, even though longer-term results are still necessary to identify the best dose/fractionation schemes.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
