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Enlace permanente de la investigaciónTreatment of invasive silent somatotroph pituitary adenoma with temozolomide. Report of a case and review of the literature / Luis Vicente Syro Moreno
Título : Treatment of invasive silent somatotroph pituitary adenoma with temozolomide. Report of a case and review of the literature Tipo de documento : documento electrónico Autores : Luis Vicente Syro Moreno, Fecha de publicación : 2015 Títulos uniformes : Endocrine Pathology Idioma : Inglés (eng) Palabras clave : MGMT pathology pituitary somatotroph adenoma temozolomide Resumen : Improved imaging techniques have contributed to increased diagnosis of pituitary tumors. These tumor types can be microadenomas or macroadenomas and can either be functional or non-functional. Atypical or aggressive pituitary adenomas are tumors that rapidly increase in size and may invade into the suprasellar or parasellar regions. They are characterized by a Ki-67 nuclear labeling index greater than 10 %. Management of these tumors is difficult, and many recur after surgery. Temozolomide, a second generation alkylating agent, has been showing promising results in the treatment of these tumors. The patient was a 39-year-old male diagnosed with an invasive silent somatotroph pituitary macroadenoma treated with temozolomide after surgery. We present the case along with the review of the literature of the therapeutic effects of temozolomide in somatotroph macroadenomas. Mención de responsabilidad : Ali A Ghazi, Fabio Rotondo, Kalman Kovacs, Alireza Amirbaigloo, Luis V Syro, Hussein Fathalla, Antonio Di Ieva, Michael D Cusimano Referencia : Endocr Pathol. 2015 May;26(2):135-9. DOI (Digital Object Identifier) : 10.1007/s12022-015-9361-z PMID : 25716461 En línea : https://link.springer.com/article/10.1007%2Fs12022-015-9361-z Enlace permanente : https://hospitalpablotobon.cloudbiteca.com/pmb/opac_css/index.php?lvl=notice_display&id=3882 Treatment of invasive silent somatotroph pituitary adenoma with temozolomide. Report of a case and review of the literature [documento electrónico] / Luis Vicente Syro Moreno, . - 2015.
Obra : Endocrine Pathology
Idioma : Inglés (eng)
Palabras clave : MGMT pathology pituitary somatotroph adenoma temozolomide Resumen : Improved imaging techniques have contributed to increased diagnosis of pituitary tumors. These tumor types can be microadenomas or macroadenomas and can either be functional or non-functional. Atypical or aggressive pituitary adenomas are tumors that rapidly increase in size and may invade into the suprasellar or parasellar regions. They are characterized by a Ki-67 nuclear labeling index greater than 10 %. Management of these tumors is difficult, and many recur after surgery. Temozolomide, a second generation alkylating agent, has been showing promising results in the treatment of these tumors. The patient was a 39-year-old male diagnosed with an invasive silent somatotroph pituitary macroadenoma treated with temozolomide after surgery. We present the case along with the review of the literature of the therapeutic effects of temozolomide in somatotroph macroadenomas. Mención de responsabilidad : Ali A Ghazi, Fabio Rotondo, Kalman Kovacs, Alireza Amirbaigloo, Luis V Syro, Hussein Fathalla, Antonio Di Ieva, Michael D Cusimano Referencia : Endocr Pathol. 2015 May;26(2):135-9. DOI (Digital Object Identifier) : 10.1007/s12022-015-9361-z PMID : 25716461 En línea : https://link.springer.com/article/10.1007%2Fs12022-015-9361-z Enlace permanente : https://hospitalpablotobon.cloudbiteca.com/pmb/opac_css/index.php?lvl=notice_display&id=3882 Reserva
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Código de barras Número de Ubicación Tipo de medio Ubicación Sección Estado DD000462 AC-2015-015 Archivo digital Producción Científica Artículos científicos Disponible
Título : O-6-methylguanine-DNA methyltransferase (MGMT) immunohistochemical expression in pituitary corticotroph adenomas Tipo de documento : documento electrónico Autores : Luis Vicente Syro Moreno, Fecha de publicación : 2012 Títulos uniformes : Neurosurgery Idioma : Inglés (eng) Palabras clave : Crooke cell adenoma cushing disease MGMT pituitary adenoma silent corticotroph adenoma temozolomide Resumen : Background: O-6-methylguanine-DNA methyltransferase (MGMT) is a DNA repair enzyme that counteracts chemotherapeutic cytotoxicity of alkylating agents such as temozolomide. Low levels of MGMT expression have been shown to correlate with longer survival in glioma patients treated with temozolomide. The same is true in pi- tuitary adenomas. Objective: We investigated the immunohistochemical expression of MGMT in a variety of corticotroph adenoma subtypes to determine the potential utility of temozolomide as a therapeutic agent. Methods: The tumors consisted of 40 cases of adrenocorticotropin-secreting pituitary tumors in Cushing disease, 12 Crooke cell adenomas, and 7 subtype I silent corticotroph adenomas. Staining for MGMT was assessed by light microscopy; nuclear reactivity was estimated semiquantitatively as present in , 10%, 10% to 25%, 25% to 50%, 50% to 75%, and . 75% of cells. Results: Immunoexpression showed no correlation with patient age, sex, tumor size, invasiveness, or recurrence in patients with Cushing disease. Among adrenocorticotropin- ecreting adenomas associated with Cushing disease, most invasive (60%) and recurrent (86%) tumors showed low MGMT immunopositivity, defined as , 25%. Most (75%) Crooke cell adenomas exhibited an MGMT immunoreactivity of # 50%. All sub-type I silent corticotroph adenomas showed , 10% MGMT staining. Conclusion: Our descriptive findings of low MGMT expression in adrenocorticotropin-producing pituitary adenomas, particularly aggressive tumors, suggest that they may be suitable candidates for temozolomide therapy. Mención de responsabilidad : Fateme Salehi, Bernd W Scheithauer, Kalman Kovacs, Eva Horvath, Luis V Syro, Soniya Sharma, Branavan Manoranjan, Michael Cusimano Referencia : Neurosurgery. 2012 Feb;70(2):491-6. DOI (Digital Object Identifier) : 10.1227/NEU.0b013e318230ac63 PMID : 21822153 En línea : https://academic.oup.com/neurosurgery/article-abstract/70/2/491/2744231?redirect [...] Enlace permanente : https://hospitalpablotobon.cloudbiteca.com/pmb/opac_css/index.php?lvl=notice_display&id=3633 O-6-methylguanine-DNA methyltransferase (MGMT) immunohistochemical expression in pituitary corticotroph adenomas [documento electrónico] / Luis Vicente Syro Moreno, . - 2012.
Obra : Neurosurgery
Idioma : Inglés (eng)
Palabras clave : Crooke cell adenoma cushing disease MGMT pituitary adenoma silent corticotroph adenoma temozolomide Resumen : Background: O-6-methylguanine-DNA methyltransferase (MGMT) is a DNA repair enzyme that counteracts chemotherapeutic cytotoxicity of alkylating agents such as temozolomide. Low levels of MGMT expression have been shown to correlate with longer survival in glioma patients treated with temozolomide. The same is true in pi- tuitary adenomas. Objective: We investigated the immunohistochemical expression of MGMT in a variety of corticotroph adenoma subtypes to determine the potential utility of temozolomide as a therapeutic agent. Methods: The tumors consisted of 40 cases of adrenocorticotropin-secreting pituitary tumors in Cushing disease, 12 Crooke cell adenomas, and 7 subtype I silent corticotroph adenomas. Staining for MGMT was assessed by light microscopy; nuclear reactivity was estimated semiquantitatively as present in , 10%, 10% to 25%, 25% to 50%, 50% to 75%, and . 75% of cells. Results: Immunoexpression showed no correlation with patient age, sex, tumor size, invasiveness, or recurrence in patients with Cushing disease. Among adrenocorticotropin- ecreting adenomas associated with Cushing disease, most invasive (60%) and recurrent (86%) tumors showed low MGMT immunopositivity, defined as , 25%. Most (75%) Crooke cell adenomas exhibited an MGMT immunoreactivity of # 50%. All sub-type I silent corticotroph adenomas showed , 10% MGMT staining. Conclusion: Our descriptive findings of low MGMT expression in adrenocorticotropin-producing pituitary adenomas, particularly aggressive tumors, suggest that they may be suitable candidates for temozolomide therapy. Mención de responsabilidad : Fateme Salehi, Bernd W Scheithauer, Kalman Kovacs, Eva Horvath, Luis V Syro, Soniya Sharma, Branavan Manoranjan, Michael Cusimano Referencia : Neurosurgery. 2012 Feb;70(2):491-6. DOI (Digital Object Identifier) : 10.1227/NEU.0b013e318230ac63 PMID : 21822153 En línea : https://academic.oup.com/neurosurgery/article-abstract/70/2/491/2744231?redirect [...] Enlace permanente : https://hospitalpablotobon.cloudbiteca.com/pmb/opac_css/index.php?lvl=notice_display&id=3633 Reserva
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Código de barras Número de Ubicación Tipo de medio Ubicación Sección Estado DD000204 AC-2012-044 Archivo digital Producción Científica Artículos científicos Disponible
Título : Temozolomide in aggressive pituitary adenomas and carcinomas Tipo de documento : documento electrónico Autores : Luis Vicente Syro Moreno, Fecha de publicación : 2012 Títulos uniformes : Clinics (Sao Paulo) Idioma : Inglés (eng) Palabras clave : Pituitary adenoma pituitary carcinoma MGMT temozolomide review Resumen : Temozolomide is an alkylating agent used in the treatment of gliomas and, more recently, aggressive pituitary adenomas and carcinomas. Temozolomide methylates DNA and, thereby, has antitumor effects. O6 -methylguanine- DNA methyltransferase, a DNA repair enzyme, removes the alkylating adducts that are induced by temozolomide, thereby counteracting its effects. A Medline search for all of the available publications regarding the use of temozolomide for the treatment of pituitary tumors was performed. To date, 46 cases of adenohypophysial tumors that were treated with temozolomide, including 30 adenomas and 16 carcinomas, have been reported. Eighteen of the 30 (60%) adenomas and 11 of the 16 (69%) carcinomas responded favorably to treatment. One patient with multiple endocrine neoplasia type 1 and an aggressive prolactin-producing adenoma was also treated and demonstrated a good response. No significant complications have been attributed to temozolomide therapy. Thus, temozolomide is an effective treatment for the majority of aggressive adenomas and carcinomas. Evidence indicates that there is an inverse correlation between levels of O6 -methylguanine-DNA methyltransferase immunoexpression and therapeutic response. Alternatively, high-level O6 -methylguanine-DNA methyltransferase immunoexpression correlates with an unfavorable response. Here, we review the use of temozolomide for treating pituitary neoplasms. Mención de responsabilidad : Leon D Ortiz, Luis V Syro, Bernd W Scheithauer, Fabio Rotondo, Humberto Uribe, Camilo E Fadul, Eva Horvath, Kalman Kovacs Referencia : Clinics. 2012;67(S1):119-23. DOI (Digital Object Identifier) : 10.6061/clinics/2012(Sup01)20 PMID : 22584716 En línea : https://www.revistas.usp.br/clinics/article/view/19731 Enlace permanente : https://hospitalpablotobon.cloudbiteca.com/pmb/opac_css/index.php?lvl=notice_display&id=3606 Temozolomide in aggressive pituitary adenomas and carcinomas [documento electrónico] / Luis Vicente Syro Moreno, . - 2012.
Obra : Clinics (Sao Paulo)
Idioma : Inglés (eng)
Palabras clave : Pituitary adenoma pituitary carcinoma MGMT temozolomide review Resumen : Temozolomide is an alkylating agent used in the treatment of gliomas and, more recently, aggressive pituitary adenomas and carcinomas. Temozolomide methylates DNA and, thereby, has antitumor effects. O6 -methylguanine- DNA methyltransferase, a DNA repair enzyme, removes the alkylating adducts that are induced by temozolomide, thereby counteracting its effects. A Medline search for all of the available publications regarding the use of temozolomide for the treatment of pituitary tumors was performed. To date, 46 cases of adenohypophysial tumors that were treated with temozolomide, including 30 adenomas and 16 carcinomas, have been reported. Eighteen of the 30 (60%) adenomas and 11 of the 16 (69%) carcinomas responded favorably to treatment. One patient with multiple endocrine neoplasia type 1 and an aggressive prolactin-producing adenoma was also treated and demonstrated a good response. No significant complications have been attributed to temozolomide therapy. Thus, temozolomide is an effective treatment for the majority of aggressive adenomas and carcinomas. Evidence indicates that there is an inverse correlation between levels of O6 -methylguanine-DNA methyltransferase immunoexpression and therapeutic response. Alternatively, high-level O6 -methylguanine-DNA methyltransferase immunoexpression correlates with an unfavorable response. Here, we review the use of temozolomide for treating pituitary neoplasms. Mención de responsabilidad : Leon D Ortiz, Luis V Syro, Bernd W Scheithauer, Fabio Rotondo, Humberto Uribe, Camilo E Fadul, Eva Horvath, Kalman Kovacs Referencia : Clinics. 2012;67(S1):119-23. DOI (Digital Object Identifier) : 10.6061/clinics/2012(Sup01)20 PMID : 22584716 En línea : https://www.revistas.usp.br/clinics/article/view/19731 Enlace permanente : https://hospitalpablotobon.cloudbiteca.com/pmb/opac_css/index.php?lvl=notice_display&id=3606 Reserva
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Código de barras Número de Ubicación Tipo de medio Ubicación Sección Estado DD000176 AC-2012-016 Archivo digital Producción Científica Artículos científicos Disponible
Título : Aggressive silent corticotroph adenoma progressing to pituitary carcinoma : the role of temozolomide therapy Tipo de documento : documento electrónico Autores : Luis Vicente Syro Moreno, Fecha de publicación : 2011 Títulos uniformes : Hormones Idioma : Inglés (eng) Palabras clave : Carcinoma MGMT pituitary adenoma temozolomide treatment Resumen : Temozolomide (TMZ) has recently been recommended as a novel approach in the management of aggressive pituitary tumors. Herein, we present the case of a 43-year-old man with a 20-year history of silent subtype 2 pituitary corticotroph adenoma. Nine surgical resections and radiotherapy had failed to provide a cure. Morphological evaluation of the tumor revealed a mildly pleomorphic adenoma, the cells of which showed low-level cell proliferative activity with Ki67, increased topoisomerase II alpha index and conclusive O-6-methylguanine-DNA methyltransferase (MGMT) as well as vascular endothelial growth factor (VEGF) immunoreactivity. Given its aggressive behavior and failure of conventional therapy, TMZ was administered. The treatment was continued even after MGMT immunopositivity was identified, but failed to decrease MGMT immunoexpression and exerted no morphologic effect. Examination of the lesion after TMZ therapy showed neither morphologic nor immunohistochemical alterations. In our case, TMZ administration, despite changing the TMZ dosing regimen to prompt a drug response, was incapable of depleting MGMT stores. Mención de responsabilidad : Olga Moshkin, Luis V Syro, Bernd W Scheithauer, Leon D Ortiz, Camilo E Fadul, Humberto Uribe, Ricardo Gonzalez, Michael Cusimano, Eva Horvath, Fabio Rotondo, Kalman Kovacs Referencia : Hormones (Athens). 2011 Apr-Jun;10(2):162-7. DOI (Digital Object Identifier) : 10.14310/horm.2002.1307 PMID : 21724542 En línea : https://link.springer.com/article/10.14310/horm.2002.1307 Enlace permanente : https://hospitalpablotobon.cloudbiteca.com/pmb/opac_css/index.php?lvl=notice_display&id=3549 Aggressive silent corticotroph adenoma progressing to pituitary carcinoma : the role of temozolomide therapy [documento electrónico] / Luis Vicente Syro Moreno, . - 2011.
Obra : Hormones
Idioma : Inglés (eng)
Palabras clave : Carcinoma MGMT pituitary adenoma temozolomide treatment Resumen : Temozolomide (TMZ) has recently been recommended as a novel approach in the management of aggressive pituitary tumors. Herein, we present the case of a 43-year-old man with a 20-year history of silent subtype 2 pituitary corticotroph adenoma. Nine surgical resections and radiotherapy had failed to provide a cure. Morphological evaluation of the tumor revealed a mildly pleomorphic adenoma, the cells of which showed low-level cell proliferative activity with Ki67, increased topoisomerase II alpha index and conclusive O-6-methylguanine-DNA methyltransferase (MGMT) as well as vascular endothelial growth factor (VEGF) immunoreactivity. Given its aggressive behavior and failure of conventional therapy, TMZ was administered. The treatment was continued even after MGMT immunopositivity was identified, but failed to decrease MGMT immunoexpression and exerted no morphologic effect. Examination of the lesion after TMZ therapy showed neither morphologic nor immunohistochemical alterations. In our case, TMZ administration, despite changing the TMZ dosing regimen to prompt a drug response, was incapable of depleting MGMT stores. Mención de responsabilidad : Olga Moshkin, Luis V Syro, Bernd W Scheithauer, Leon D Ortiz, Camilo E Fadul, Humberto Uribe, Ricardo Gonzalez, Michael Cusimano, Eva Horvath, Fabio Rotondo, Kalman Kovacs Referencia : Hormones (Athens). 2011 Apr-Jun;10(2):162-7. DOI (Digital Object Identifier) : 10.14310/horm.2002.1307 PMID : 21724542 En línea : https://link.springer.com/article/10.14310/horm.2002.1307 Enlace permanente : https://hospitalpablotobon.cloudbiteca.com/pmb/opac_css/index.php?lvl=notice_display&id=3549 Reserva
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Código de barras Número de Ubicación Tipo de medio Ubicación Sección Estado DD000118 AC-2011-003 Archivo digital Producción Científica Artículos científicos Disponible
Título : Treatment of pituitary neoplasms with temozolomide: a review Tipo de documento : documento electrónico Autores : Luis Vicente Syro Moreno, Fecha de publicación : 2011 Títulos uniformes : Cancer Idioma : Inglés (eng) Palabras clave : Temozolomide pituitary carcinoma pituitary adenoma O6 methylguanine-DNA methyltransferase MGMT treatment Resumen : Temozolomide, an orally administered alkylating agent, is used to treat malignant gliomas. Recent reports also have documented its efficacy in the treatment of pituitary adenomas and carcinomas. Temozolomide methylates DNA and thereby exhibits an antitumor effect. O6‐methylguanine‐DNA methyltransferase (MGMT), a DNA repair enzyme, removes alkylating adducts induced by temozolomide, counteracting its effects. The authors of this review conducted a Medline database search regarding temozolomide in the treatment of pituitary tumors. Demographic characteristics, tumor types, and therapeutic responses were noted in all patients. Data regarding MGMT immunoexpression, which was documented in some studies, were correlated with information regarding clinical and radiologic responses. To date, there have been 19 reported cases of adenohypophyseal tumors treated with temozolomide, including 13 adenomas and 6 carcinomas. Ten of those 13 adenomas responded favorably, and 2 nonresponsive tumors had high‐level MGMT immunoexpression. All 6 carcinomas responded to therapy, but data regarding MGMT expression were available for only 3 patients, and each had low MGMT expression. In 2 adenomas, morphologic studies were performed both before and after the patients received temozolomide. The responsive tumor had necrosis, hemorrhage, fibrosis, and neuronal differentiation. The nonresponsive tumor had no changes. There have been no reported complications attributable to temozolomide. The current results indicated that temozolomide is efficacious in the treatment of aggressive pituitary adenomas and pituitary carcinomas. Evidence indicated that low‐level MGMT immunoexpression is correlated with a favorable response. A significant proportion of pituitary adenomas and carcinomas had low MGMT immunoexpression. Mención de responsabilidad : Luis V Syro, Leon D Ortiz, Bernd W Scheithauer, Ricardo Lloyd, Queenie Lau, Ricardo Gonzalez, Humberto Uribe, Michael Cusimano, Kalman Kovacs, Eva Horvath Referencia : Cancer. 2011 Feb 1;117(3):454-62. DOI (Digital Object Identifier) : 10.1002/cncr.25413 PMID : 20845485 En línea : https://onlinelibrary.wiley.com/doi/10.1002/cncr.25413 Enlace permanente : https://hospitalpablotobon.cloudbiteca.com/pmb/opac_css/index.php?lvl=notice_display&id=3576 Treatment of pituitary neoplasms with temozolomide: a review [documento electrónico] / Luis Vicente Syro Moreno, . - 2011.
Obra : Cancer
Idioma : Inglés (eng)
Palabras clave : Temozolomide pituitary carcinoma pituitary adenoma O6 methylguanine-DNA methyltransferase MGMT treatment Resumen : Temozolomide, an orally administered alkylating agent, is used to treat malignant gliomas. Recent reports also have documented its efficacy in the treatment of pituitary adenomas and carcinomas. Temozolomide methylates DNA and thereby exhibits an antitumor effect. O6‐methylguanine‐DNA methyltransferase (MGMT), a DNA repair enzyme, removes alkylating adducts induced by temozolomide, counteracting its effects. The authors of this review conducted a Medline database search regarding temozolomide in the treatment of pituitary tumors. Demographic characteristics, tumor types, and therapeutic responses were noted in all patients. Data regarding MGMT immunoexpression, which was documented in some studies, were correlated with information regarding clinical and radiologic responses. To date, there have been 19 reported cases of adenohypophyseal tumors treated with temozolomide, including 13 adenomas and 6 carcinomas. Ten of those 13 adenomas responded favorably, and 2 nonresponsive tumors had high‐level MGMT immunoexpression. All 6 carcinomas responded to therapy, but data regarding MGMT expression were available for only 3 patients, and each had low MGMT expression. In 2 adenomas, morphologic studies were performed both before and after the patients received temozolomide. The responsive tumor had necrosis, hemorrhage, fibrosis, and neuronal differentiation. The nonresponsive tumor had no changes. There have been no reported complications attributable to temozolomide. The current results indicated that temozolomide is efficacious in the treatment of aggressive pituitary adenomas and pituitary carcinomas. Evidence indicated that low‐level MGMT immunoexpression is correlated with a favorable response. A significant proportion of pituitary adenomas and carcinomas had low MGMT immunoexpression. Mención de responsabilidad : Luis V Syro, Leon D Ortiz, Bernd W Scheithauer, Ricardo Lloyd, Queenie Lau, Ricardo Gonzalez, Humberto Uribe, Michael Cusimano, Kalman Kovacs, Eva Horvath Referencia : Cancer. 2011 Feb 1;117(3):454-62. DOI (Digital Object Identifier) : 10.1002/cncr.25413 PMID : 20845485 En línea : https://onlinelibrary.wiley.com/doi/10.1002/cncr.25413 Enlace permanente : https://hospitalpablotobon.cloudbiteca.com/pmb/opac_css/index.php?lvl=notice_display&id=3576 Reserva
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