Lani
02-02-2010, 03:24 PM
important brain cognitive function
"The limbic system performs a number of vital functions including acquisition and consolidation of memory, regulation of emotional and autonomic responses to external stimuli, psychomotor activation, concentration/ attention span, executive planning, and visual-spatial orientation. Based on many years of clinical experience in treating intracranial metastases, we have noted a very low incidence of involvement of the limbic circuit in metastatic disease. We postulate that it may be reasonable and safe to exclude and/or reduce the dose to these structures when treating patients with either whole-brain radiation therapy (WBRT) or prophylactic cranial irradiation (PCI). In order to confirm this hypothesis, we performed this study."
Int J Radiat Oncol Biol Phys. 2010 Feb 1;76(2):504-512.
Intracranial Metastatic Disease Spares the Limbic Circuit: A Review of 697 Metastatic Lesions in 107 Patients.
Marsh JC, Herskovic AM, Gielda BT, Hughes FF, Hoeppner T, Turian J, Abrams RA.
Department of Radiation Oncology, Rush University Medical Center, Chicago, Illinois.
PURPOSE: We report the incidence of metastatic involvement of the limbic circuit in a retrospective review of patients treated at our institution. This review was performed to assess the feasibility of selectively sparing the limbic system during whole-brain radiotherapy and prophylactic cranial irradiation. METHODS AND MATERIALS: We identified 697 intracranial metastases in 107 patients after reviewing contrast-enhanced CT and/or MR image sets for each patient. Lesions were localized to the limbic circuit or to the rest of the brain/brain stem. Patients were categorized by tumor histology (e.g., non-small-cell lung cancer, small-cell lung cancer, breast cancer, and other) and by total number of intracranial metastases (1-3, oligometastatic; 4 or more, nonoligometastatic). RESULTS: Thirty-six limbic metastases (5.2% of all metastases) were identified in 22 patients who had a median of 16.5 metastases/patient (limbic metastases accounted for 9.9% of their lesions). Sixteen metastases (2.29%) involved the hippocampus, and 20 (2.86%) involved the rest of the limbic circuit; 86.2% of limbic metastases occurred in nonoligometastatic patients, and 13.8% occurred in oligometastatic patients. The incidence of limbic metastases by histologic subtype was similar. The incidence of limbic metastases in oligometastatic patients was 4.9% (5/103): 0.97%, hippocampus; 3.9%, remainder of the limbic circuit. One of 53 oligometastatic patients (1.9%) had hippocampal metastases, while 4/53 (7.5%) had other limbic metastases. CONCLUSIONS: Metastatic involvement of the limbic circuit is uncommon and limited primarily to patients with nonoligometastatic disease, supporting our hypothesis that it is reasonable to selectively exclude or reduce the dose to the limbic circuit when treating patients with prophylactic cranial irradiation or whole-brain radiotherapy for oligometastatic disease not involving these structures. Copyright © 2010 Elsevier Inc. All rights reserved.
PMID: 20117288 [PubMed - as supplied by publisher]
"The limbic system performs a number of vital functions including acquisition and consolidation of memory, regulation of emotional and autonomic responses to external stimuli, psychomotor activation, concentration/ attention span, executive planning, and visual-spatial orientation. Based on many years of clinical experience in treating intracranial metastases, we have noted a very low incidence of involvement of the limbic circuit in metastatic disease. We postulate that it may be reasonable and safe to exclude and/or reduce the dose to these structures when treating patients with either whole-brain radiation therapy (WBRT) or prophylactic cranial irradiation (PCI). In order to confirm this hypothesis, we performed this study."
Int J Radiat Oncol Biol Phys. 2010 Feb 1;76(2):504-512.
Intracranial Metastatic Disease Spares the Limbic Circuit: A Review of 697 Metastatic Lesions in 107 Patients.
Marsh JC, Herskovic AM, Gielda BT, Hughes FF, Hoeppner T, Turian J, Abrams RA.
Department of Radiation Oncology, Rush University Medical Center, Chicago, Illinois.
PURPOSE: We report the incidence of metastatic involvement of the limbic circuit in a retrospective review of patients treated at our institution. This review was performed to assess the feasibility of selectively sparing the limbic system during whole-brain radiotherapy and prophylactic cranial irradiation. METHODS AND MATERIALS: We identified 697 intracranial metastases in 107 patients after reviewing contrast-enhanced CT and/or MR image sets for each patient. Lesions were localized to the limbic circuit or to the rest of the brain/brain stem. Patients were categorized by tumor histology (e.g., non-small-cell lung cancer, small-cell lung cancer, breast cancer, and other) and by total number of intracranial metastases (1-3, oligometastatic; 4 or more, nonoligometastatic). RESULTS: Thirty-six limbic metastases (5.2% of all metastases) were identified in 22 patients who had a median of 16.5 metastases/patient (limbic metastases accounted for 9.9% of their lesions). Sixteen metastases (2.29%) involved the hippocampus, and 20 (2.86%) involved the rest of the limbic circuit; 86.2% of limbic metastases occurred in nonoligometastatic patients, and 13.8% occurred in oligometastatic patients. The incidence of limbic metastases by histologic subtype was similar. The incidence of limbic metastases in oligometastatic patients was 4.9% (5/103): 0.97%, hippocampus; 3.9%, remainder of the limbic circuit. One of 53 oligometastatic patients (1.9%) had hippocampal metastases, while 4/53 (7.5%) had other limbic metastases. CONCLUSIONS: Metastatic involvement of the limbic circuit is uncommon and limited primarily to patients with nonoligometastatic disease, supporting our hypothesis that it is reasonable to selectively exclude or reduce the dose to the limbic circuit when treating patients with prophylactic cranial irradiation or whole-brain radiotherapy for oligometastatic disease not involving these structures. Copyright © 2010 Elsevier Inc. All rights reserved.
PMID: 20117288 [PubMed - as supplied by publisher]