DESCRIPTION Una guia para el manejo enfocado especialmente en tumores hipofisarios funcionantes y... more DESCRIPTION Una guia para el manejo enfocado especialmente en tumores hipofisarios funcionantes y no funcionantes
Mortality rate is dramatically high in high grade brain tumors. The presence of multiple drug res... more Mortality rate is dramatically high in high grade brain tumors. The presence of multiple drug resistance transporters in glioblastoma multiforme, has contributed largely to the poor efficacy of targeted therapy against cancer in the central nervous system. To analyze the percentage of survival and mortality of patients with glioblastoma multiforme in a cohort of patients in Chile and to co-rrelate the chemo-resistance of these cells with the expression level of multiple drug resistance transporters. Eighteen biopsies of glioblastoma multiforme were obtained from patients at the Institute of Neurosurgery Dr. Asenjo (INCA). The tumor cells were obtained from primary cultures and the expression and activity of multiple drug resistance transporters was assessed by RT-PCR and immunohistochemistry. Population-based study was performed using the databases of the Department of Neurosurgery of INCA. The number of patients with glioblastoma multiforme increased between 2007 and 2009, from 3.5...
ABSTRACT Vestibular Schwannomas (VS) are benign intracranial tumors, for which their current mana... more ABSTRACT Vestibular Schwannomas (VS) are benign intracranial tumors, for which their current management is a matter of debate, although microsurgical treatment remains the mode of choice in the majority of cases.
Primary pituitary lymphoma in immunocompetent patients is a rare disease and has been described i... more Primary pituitary lymphoma in immunocompetent patients is a rare disease and has been described in less than 20 cases. Moreover, low-grade lymphomas constitute only 3% of all primary central nervous system lymphoma. The objective of this report is to report a low-grade primary pituitary lymphoma, diagnostic problems and to give more evidence about the evolution of this rare disease. A 49 y.o. woman was referred to our clinic with symptoms of hypopituitarism. A diagnostic work-up showed mild anemia, an erythrocyte sedimentation rate of 122 mm/h and a negative Elisa test for HIV. Panhypopituitarism was confirmed and the MRI showed a 20 mm sellar and suprasellar enhancing mass with a thickening of the pituitary stalk, chiasmal compression and bitemporal hemianopsia. She underwent transsphenoidal resection only 10 months later for non medical reasons. During this period she was clinically asymptomatic on hormonal replacement therapy. A new MRI showed regression of the suprasellar extension and invasion to the left cavernous sinus. A firm and infiltrative mass was found during transsphenoidal surgery, and only partial resection was performed. Biopsy showed a low-grade lymphoplasmacytic lymphoma. Staging was negative for other localizations. She was given chemotherapy and localized radiotherapy. Four years after surgery, the sellar MRI showed a 10 mm residual sellar mass with the persistence of a cavernous sinus invasion and she is considered to be in remission. The neurosurgeon and clinician should consider primary pituitary lymphoma as a potential cause of a sellar mass, especially in the presence of diabetes insipidus and an enhancing invasive mass. Neurosurgical biopsy is crucial for a correct diagnosis and prognosis could be better than classic CNS primary lymphomas.
A continuación se muestra la forma de presentación y de evaluación de los principales tipos de ad... more A continuación se muestra la forma de presentación y de evaluación de los principales tipos de adenomas hipofisiarios. En este artículo se enfocará la discusión en los adenomas no funcionantes. Estos constituyen entre el 20 y 50% de los adenomas hipofisiarios 5-7 , pero las consideraciones clínicas referidas a su volumen, son válidas para todas las estirpes.
Arterial embolization with cyanoacrylate is commonly used for the treatment of arteriovenous malf... more Arterial embolization with cyanoacrylate is commonly used for the treatment of arteriovenous malformations. We report the case of a 40 years old man who four days after an embolization with cyanoacrylate, begins with cough, bloody sputum, and right hemithorax pleuritic pain. Pulmonary embolism was confirmed with chest X ray, CT scan and scyntigraphy. The patient received anticoagulation, with adequate response. The most common complications of cerebral embolization are related to central nervous system and pulmonary embolism is exceptional. Considering the high number of embolization procedures done nowadays, this complication must be borne in mind.
Dopamine agonists (DA) effectively reduce tumor size of macroprolactinomas, with the consequent i... more Dopamine agonists (DA) effectively reduce tumor size of macroprolactinomas, with the consequent improvement of eventual visual impairment. To study the visual outcomes in patients with macroprolactinoma treated with DA. Retrospective cohort study which included patients with macroprolactinoma controlled at a Neuro-endocrinology and Neuro-ophthalmology Department between 1997 and 2011, and treated exclusively with DA (bromocriptine or cabergoline). Patients who were operated or had previous radiotherapy and those with an incomplete follow up, were excluded. We analyzed and compared the visual status before and after the beginning of DA treatment. Thirty one patients aged 8 to 59 years, were included. Eighteen patients (58%) had visual impairment at the moment of diagnosis (group 1) and 13 had no alterations (group 2). Mean follow up was 36.5 months. Fifteen patients from group 1 (83%) had visual improvement, two remained stable (11 %) and one had a visual deterioration (6%). In group...
Background: Mortality rate is dramatically high in high-grade brain tumors. The presence of multi... more Background: Mortality rate is dramatically high in high-grade brain tumors. The presence of multiple drug resistance transporters in glioblastoma multiforme, has contributed largely to the poor efficacy of targeted therapy against cancer in the central nervous system. Aim: To analyze the percentage of survival and mortality of patients with glioblastoma multiforme in a cohort of patients in Chile and to correlate the chemo-resistance of these cells with the expression level of multiple drug resistance transporters. Materials and Methods: Eighteen biopsies of glioblastoma multiforme were obtained from patients at the Institute of Neurosurgery Dr. Asenjo (INCA). The tumor cells were obtained from primary cultures and the expression and activity of multiple drug resistance transporters was assessed by RT-PCR and immunohistochemistry. Population-based study was performed using the databases of the Department of Neurosurgery of INCA. Results: The number of patients with glioblastoma multiforme increased between 2007 and 2009, from 3.5% to 7.9% of total brain tumors. Mortality of these tumors is 90 % at three years. A high expression and activity of the multiple drugs resistance associated protein 1 (Mrp1) transporter was observed in primary cultures of biopsies. Conclusions: We propose that Mrp1 activity is responsible for the chemo-resistance of the glioblastoma multiforme and inhibition of this transporter could represent a plausible strategy for the treatment. (Rev Med Chile 2011; 139: 415-424).
ABSTRACT Background: The treatment of choice for acromegaly is surgery that, according to the lit... more ABSTRACT Background: The treatment of choice for acromegaly is surgery that, according to the literature, is curative in 91% of pituitary microadenomas and 73% of macroadenomas. Aim: To report the results of surgical treatment in 53 patients with acromegaly. Material and methods: Retrospective review of medical records of all patients with acromegaly, operated between 1984 and 2004. When necessary, patients were contacted by telephone to complete information or to perform biochemical or imaging studies. A normal value of insulin like growth factor I (IGF-1) for age and sex, a growth hormone (GH) nadir of less than 1 ng/ml during a glucose tolerance test or a basal GH of less than 2.5 ng/ml, all assessed three months after surgery, were considered as criteria for cure. Results: Biochemical cure was achieved in 67% of patients with pituitary microadenomas and 21% of patients with macroadenomas. In 47% of patients with neuro-ophtalmological involvement, a partial or total recovery in the visual field defect was achieved. The most common surgical complications were transient diabetes insipidus in 19%, persistent diabetes insipidus in 4% and cerebrospinal fluid fistula in 4%. A lower size of the tumor and lower preoperative growth hormone levels were associated with a better chance of cure. Conclusions: The cure rates obtained in this group of patients are clearly lower than those reported abroad. These results stress the importance of having a national registry of acromegaly and the need to train neurosurgeons in the treatment of pituitary tumors.
Glioblastoma multiforme (GBM) is a brain tumour characterised by a remarkably high chemoresistanc... more Glioblastoma multiforme (GBM) is a brain tumour characterised by a remarkably high chemoresistance and infiltrating capability. To date, chemotherapy with temozolomide has contributed only poorly to improved survival rates in patients. One of the most important mechanisms of chemoresistance comes about through the activity of certain proteins from the ATPbinding cassette superfamily that extrudes antitumour drugs, or their metabolites, from cells. We identify an increased expression of the multiple drug resistance-associated protein 1 (Mrp1) in glioblastoma multiforme biopsies and in T98G and G44 cell lines. The activity of this transporter was also confirmed by measuring the extrusion of the fluorescent substrate CFDA. The sensitivity of GBM cells was low upon exposure to temozolomide, vincristine and etoposide, with decreases in cell viability of below 20% seen at therapeutic concentrations of these drugs. However, combined exposure to vincristine or etoposide with an inhibitor of Mrp1 efficiently decreased cell viability by up to 80%. We conclude that chemosensitization of cells with inhibitors of Mrp1 activity might be an efficient tool for the treatment of human GBM.
Cavernomas, or cavernous angiomas, are benign vascular hamartomatous malformations; they are almo... more Cavernomas, or cavernous angiomas, are benign vascular hamartomatous malformations; they are almost always located supratentorially in the brain. The prevalence is about 0.1 to 4% of the general population, and they may arise in sporadic or familial forms. The present ...
DESCRIPTION Una guia para el manejo enfocado especialmente en tumores hipofisarios funcionantes y... more DESCRIPTION Una guia para el manejo enfocado especialmente en tumores hipofisarios funcionantes y no funcionantes
Mortality rate is dramatically high in high grade brain tumors. The presence of multiple drug res... more Mortality rate is dramatically high in high grade brain tumors. The presence of multiple drug resistance transporters in glioblastoma multiforme, has contributed largely to the poor efficacy of targeted therapy against cancer in the central nervous system. To analyze the percentage of survival and mortality of patients with glioblastoma multiforme in a cohort of patients in Chile and to co-rrelate the chemo-resistance of these cells with the expression level of multiple drug resistance transporters. Eighteen biopsies of glioblastoma multiforme were obtained from patients at the Institute of Neurosurgery Dr. Asenjo (INCA). The tumor cells were obtained from primary cultures and the expression and activity of multiple drug resistance transporters was assessed by RT-PCR and immunohistochemistry. Population-based study was performed using the databases of the Department of Neurosurgery of INCA. The number of patients with glioblastoma multiforme increased between 2007 and 2009, from 3.5...
ABSTRACT Vestibular Schwannomas (VS) are benign intracranial tumors, for which their current mana... more ABSTRACT Vestibular Schwannomas (VS) are benign intracranial tumors, for which their current management is a matter of debate, although microsurgical treatment remains the mode of choice in the majority of cases.
Primary pituitary lymphoma in immunocompetent patients is a rare disease and has been described i... more Primary pituitary lymphoma in immunocompetent patients is a rare disease and has been described in less than 20 cases. Moreover, low-grade lymphomas constitute only 3% of all primary central nervous system lymphoma. The objective of this report is to report a low-grade primary pituitary lymphoma, diagnostic problems and to give more evidence about the evolution of this rare disease. A 49 y.o. woman was referred to our clinic with symptoms of hypopituitarism. A diagnostic work-up showed mild anemia, an erythrocyte sedimentation rate of 122 mm/h and a negative Elisa test for HIV. Panhypopituitarism was confirmed and the MRI showed a 20 mm sellar and suprasellar enhancing mass with a thickening of the pituitary stalk, chiasmal compression and bitemporal hemianopsia. She underwent transsphenoidal resection only 10 months later for non medical reasons. During this period she was clinically asymptomatic on hormonal replacement therapy. A new MRI showed regression of the suprasellar extension and invasion to the left cavernous sinus. A firm and infiltrative mass was found during transsphenoidal surgery, and only partial resection was performed. Biopsy showed a low-grade lymphoplasmacytic lymphoma. Staging was negative for other localizations. She was given chemotherapy and localized radiotherapy. Four years after surgery, the sellar MRI showed a 10 mm residual sellar mass with the persistence of a cavernous sinus invasion and she is considered to be in remission. The neurosurgeon and clinician should consider primary pituitary lymphoma as a potential cause of a sellar mass, especially in the presence of diabetes insipidus and an enhancing invasive mass. Neurosurgical biopsy is crucial for a correct diagnosis and prognosis could be better than classic CNS primary lymphomas.
A continuación se muestra la forma de presentación y de evaluación de los principales tipos de ad... more A continuación se muestra la forma de presentación y de evaluación de los principales tipos de adenomas hipofisiarios. En este artículo se enfocará la discusión en los adenomas no funcionantes. Estos constituyen entre el 20 y 50% de los adenomas hipofisiarios 5-7 , pero las consideraciones clínicas referidas a su volumen, son válidas para todas las estirpes.
Arterial embolization with cyanoacrylate is commonly used for the treatment of arteriovenous malf... more Arterial embolization with cyanoacrylate is commonly used for the treatment of arteriovenous malformations. We report the case of a 40 years old man who four days after an embolization with cyanoacrylate, begins with cough, bloody sputum, and right hemithorax pleuritic pain. Pulmonary embolism was confirmed with chest X ray, CT scan and scyntigraphy. The patient received anticoagulation, with adequate response. The most common complications of cerebral embolization are related to central nervous system and pulmonary embolism is exceptional. Considering the high number of embolization procedures done nowadays, this complication must be borne in mind.
Dopamine agonists (DA) effectively reduce tumor size of macroprolactinomas, with the consequent i... more Dopamine agonists (DA) effectively reduce tumor size of macroprolactinomas, with the consequent improvement of eventual visual impairment. To study the visual outcomes in patients with macroprolactinoma treated with DA. Retrospective cohort study which included patients with macroprolactinoma controlled at a Neuro-endocrinology and Neuro-ophthalmology Department between 1997 and 2011, and treated exclusively with DA (bromocriptine or cabergoline). Patients who were operated or had previous radiotherapy and those with an incomplete follow up, were excluded. We analyzed and compared the visual status before and after the beginning of DA treatment. Thirty one patients aged 8 to 59 years, were included. Eighteen patients (58%) had visual impairment at the moment of diagnosis (group 1) and 13 had no alterations (group 2). Mean follow up was 36.5 months. Fifteen patients from group 1 (83%) had visual improvement, two remained stable (11 %) and one had a visual deterioration (6%). In group...
Background: Mortality rate is dramatically high in high-grade brain tumors. The presence of multi... more Background: Mortality rate is dramatically high in high-grade brain tumors. The presence of multiple drug resistance transporters in glioblastoma multiforme, has contributed largely to the poor efficacy of targeted therapy against cancer in the central nervous system. Aim: To analyze the percentage of survival and mortality of patients with glioblastoma multiforme in a cohort of patients in Chile and to correlate the chemo-resistance of these cells with the expression level of multiple drug resistance transporters. Materials and Methods: Eighteen biopsies of glioblastoma multiforme were obtained from patients at the Institute of Neurosurgery Dr. Asenjo (INCA). The tumor cells were obtained from primary cultures and the expression and activity of multiple drug resistance transporters was assessed by RT-PCR and immunohistochemistry. Population-based study was performed using the databases of the Department of Neurosurgery of INCA. Results: The number of patients with glioblastoma multiforme increased between 2007 and 2009, from 3.5% to 7.9% of total brain tumors. Mortality of these tumors is 90 % at three years. A high expression and activity of the multiple drugs resistance associated protein 1 (Mrp1) transporter was observed in primary cultures of biopsies. Conclusions: We propose that Mrp1 activity is responsible for the chemo-resistance of the glioblastoma multiforme and inhibition of this transporter could represent a plausible strategy for the treatment. (Rev Med Chile 2011; 139: 415-424).
ABSTRACT Background: The treatment of choice for acromegaly is surgery that, according to the lit... more ABSTRACT Background: The treatment of choice for acromegaly is surgery that, according to the literature, is curative in 91% of pituitary microadenomas and 73% of macroadenomas. Aim: To report the results of surgical treatment in 53 patients with acromegaly. Material and methods: Retrospective review of medical records of all patients with acromegaly, operated between 1984 and 2004. When necessary, patients were contacted by telephone to complete information or to perform biochemical or imaging studies. A normal value of insulin like growth factor I (IGF-1) for age and sex, a growth hormone (GH) nadir of less than 1 ng/ml during a glucose tolerance test or a basal GH of less than 2.5 ng/ml, all assessed three months after surgery, were considered as criteria for cure. Results: Biochemical cure was achieved in 67% of patients with pituitary microadenomas and 21% of patients with macroadenomas. In 47% of patients with neuro-ophtalmological involvement, a partial or total recovery in the visual field defect was achieved. The most common surgical complications were transient diabetes insipidus in 19%, persistent diabetes insipidus in 4% and cerebrospinal fluid fistula in 4%. A lower size of the tumor and lower preoperative growth hormone levels were associated with a better chance of cure. Conclusions: The cure rates obtained in this group of patients are clearly lower than those reported abroad. These results stress the importance of having a national registry of acromegaly and the need to train neurosurgeons in the treatment of pituitary tumors.
Glioblastoma multiforme (GBM) is a brain tumour characterised by a remarkably high chemoresistanc... more Glioblastoma multiforme (GBM) is a brain tumour characterised by a remarkably high chemoresistance and infiltrating capability. To date, chemotherapy with temozolomide has contributed only poorly to improved survival rates in patients. One of the most important mechanisms of chemoresistance comes about through the activity of certain proteins from the ATPbinding cassette superfamily that extrudes antitumour drugs, or their metabolites, from cells. We identify an increased expression of the multiple drug resistance-associated protein 1 (Mrp1) in glioblastoma multiforme biopsies and in T98G and G44 cell lines. The activity of this transporter was also confirmed by measuring the extrusion of the fluorescent substrate CFDA. The sensitivity of GBM cells was low upon exposure to temozolomide, vincristine and etoposide, with decreases in cell viability of below 20% seen at therapeutic concentrations of these drugs. However, combined exposure to vincristine or etoposide with an inhibitor of Mrp1 efficiently decreased cell viability by up to 80%. We conclude that chemosensitization of cells with inhibitors of Mrp1 activity might be an efficient tool for the treatment of human GBM.
Cavernomas, or cavernous angiomas, are benign vascular hamartomatous malformations; they are almo... more Cavernomas, or cavernous angiomas, are benign vascular hamartomatous malformations; they are almost always located supratentorially in the brain. The prevalence is about 0.1 to 4% of the general population, and they may arise in sporadic or familial forms. The present ...
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