ABSTRACT
BACKGROUND: Classification of growth hormone (GH) - secreting tumors by the granular pattern might predict their clinical behavior in acromegalic patients. There are several other prognostic factors. AIM: To compare the features at presentation and cure rates of patients with GH secreting tumors according to the granular pattern, and to define independent prognostic factors for surgical treatment in these patients. MATERIAL AND METHODS: A retrospective, observational study of 85 active acromegalic patients surgically treated in two medical centers. RESULTS: Seventy-four patients (87%) were classified as having densely granulated (DG) and 11 (13%) as sparsely granulated (SG) tumors. The latter were less active biochemically, had a higher rate of macroadenoma and cavernous sinus invasion and had a lower rate of biochemical cure than the DG group. Several characteristics were associated with disease persistence but only age (Odds ratio (OR) = 0.93) and cavernous sinus invasion (OR = 21.7) were independently associated in the logistic regression model. CONCLUSIONS: The sparsely granulated pattern is associated with a more aggressive behavior, but the main determinants of prognosis are age and cavernous sinus invasion.
Subject(s)
Growth Hormone-Secreting Pituitary Adenoma/pathology , Adult , Female , Growth Hormone-Secreting Pituitary Adenoma/diagnostic imaging , Humans , Immunohistochemistry , Magnetic Resonance Imaging , Male , Middle Aged , Prognosis , Retrospective StudiesABSTRACT
Background: Classification of growth hormone (GH) - secreting tumors by the granular pattern might predict their clinical behavior in acromegalic patients. There are several other prognostic factors. Aim: To compare the features at presentation and cure rates of patients with GH secreting tumors according to the granular pattern, and to define independent prognostic factors for surgical treatment in these patients. Material and Methods: A retrospective, observational study of 85 active acromegalic patients surgically treated in two medical centers. Results: Seventy-four patients (87%) were classified as having densely granulated (DG) and 11 (13%) as sparsely granulated (SG) tumors. The latter were less active biochemically, had a higher rate of macroadenoma and cavernous sinus invasion and had a lower rate of biochemical cure than the DG group. Several characteristics were associated with disease persistence but only age (Odds ratio (OR) = 0.93) and cavernous sinus invasion (OR = 21.7) were independently associated in the logistic regression model. Conclusions: The sparsely granulated pattern is associated with a more aggressive behavior, but the main determinants of prognosis are age and cavernous sinus invasion.
Subject(s)
Growth Hormone-Secreting Pituitary Adenoma/pathology , Prognosis , Immunohistochemistry , Magnetic Resonance Imaging , Retrospective Studies , Growth Hormone-Secreting Pituitary Adenoma/diagnostic imagingABSTRACT
BACKGROUND: Patients with Glioblastoma multiforme (GBM) have a five years survival of less than 5%, but the response to chemotherapy with alkylating agents can vary depending on the methylation status of O6-methylguanine-DNA-methyltransferase (MGMT). Genetic testing has limitations for routine use, while immunohistochemistry (IHC) offers a fast and affordable technique but with heterogeneous results in the literature. AIM: To evaluate MGMT expression by IHC in tumor tissue of Chilean patients with GBM. MATERIAL AND METHODS: Tumor samples of 29 patients with a pathological diagnosis of GBM were studied. We performed IHC staining and manual analysis of positive and negative cells for MGMT expression. A cut-off of at least 10% of cells expressing MGMT was used. Demographic and clinical features of patients were obtained from clinical records. RESULTS: The median number of cells counted per case was 692 (interquartile range [IQR] 492-928). Fifteen cases (52%) were positive for MGMT expression. Median overall survival was 5.3 months (IQR 3.4-12-8). The effect of MGMT expression on the therapeutic response was not studied since only 3 patients received chemotherapy. CONCLUSIONS: Our results are similar to international reports, but we were not able to determine the association between MGMT expression and therapeutic response.
Subject(s)
Biomarkers, Tumor/metabolism , Brain Neoplasms/enzymology , Glioblastoma/enzymology , O(6)-Methylguanine-DNA Methyltransferase/metabolism , Adult , Aged , Biomarkers, Tumor/genetics , Brain Neoplasms/genetics , Chile , Female , Gene Expression Regulation, Neoplastic , Glioblastoma/genetics , Humans , Immunohistochemistry , Male , Middle Aged , O(6)-Methylguanine-DNA Methyltransferase/genetics , Prognosis , Retrospective Studies , Survival RateABSTRACT
Background: Patients with Glioblastoma multiforme (GBM) have a five years survival of less than 5%, but the response to chemotherapy with alkylating agents can vary depending on the methylation status of O6-methylguanine-DNA-methyltransferase (MGMT). Genetic testing has limitations for routine use, while immunohistochemistry (IHC) offers a fast and affordable technique but with heterogeneous results in the literature. Aim: To evaluate MGMT expression by IHC in tumor tissue of Chilean patients with GBM. Material and Methods: Tumor samples of 29 patients with a pathological diagnosis of GBM were studied. We performed IHC staining and manual analysis of positive and negative cells for MGMT expression. A cut-off of at least 10% of cells expressing MGMT was used. Demographic and clinical features of patients were obtained from clinical records. Results: The median number of cells counted per case was 692 (interquartile range [IQR] 492-928). Fifteen cases (52%) were positive for MGMT expression. Median overall survival was 5.3 months (IQR 3.4-12-8). The effect of MGMT expression on the therapeutic response was not studied since only 3 patients received chemotherapy. Conclusions: Our results are similar to international reports, but we were not able to determine the association between MGMT expression and therapeutic response.
Subject(s)
Humans , Male , Female , Adult , Middle Aged , Aged , Brain Neoplasms/enzymology , Biomarkers, Tumor/metabolism , Glioblastoma/enzymology , O(6)-Methylguanine-DNA Methyltransferase/metabolism , Prognosis , Brain Neoplasms/genetics , Immunohistochemistry , Biomarkers, Tumor , Gene Expression Regulation, Neoplastic , Chile , Survival Rate , Retrospective Studies , Glioblastoma/genetics , O(6)-Methylguanine-DNA Methyltransferase/geneticsABSTRACT
Immunohistochemistry (IHC) for O6-methylguanine-DNA-methyltransferase (MGMT) has shown heterogeneous results. Cell staining intensity has not been included as a quantifiable variable in IHC analyses. We performed MGMT IHC in 29 patients diagnosed as glioblastoma classifying cells into three categories based on nuclear staining intensity compared with adjacent endothelium. The median proportions of strong-moderate, weak and no staining cells were 10%, 16% and 71%, respectively. The proportion of positive cases for MGMT expression varies from 38% to 52% depending on the classification of weakly stained cells. This letter challenges previous studies that have not included intensity as a variable for IHC analysis.
