Prognostic significance of O6-methylguanine-DNA methyltransferase determined by promoter hypermethylation and immunohistochemical expression in anaplastic gliomas.

PURPOSE: Anaplastic gliomas constitute a heterogeneous group of tumors with different therapeutic responses to adjuvant chemotherapy with alkylating agents. O6-Methylguanine-DNA methyltransferase (MGMT), a DNA repair protein, is one of the implicated factors in glioma chemoresistance. The prognostic value of MGMT remains controversial due in part to the fact that previous published studies included heterogeneous groups of patients with different tumor grades. The aim of this study was to evaluate the prognostic significance of MGMT in patients with anaplastic glioma. EXPERIMENTAL DESIGN: Ninety-three patients with anaplastic glioma were analyzed for MGMT protein expression by immunohistochemistry. In addition, for those patients from whom a good yield of DNA was obtained (n = 40), MGMT promoter methylation profile was analyzed by methylation-specific PCR. MGMT prognostic significance was evaluated together with other well-known prognostic factors. RESULTS: Fifty-one tumors (54.8%) showed nuclear staining of MGMT. There was a trend towards longer overall survival for those patients with negative MGMT immunostaining (hazard ratio, 1.66; P = 0.066). In a secondary analysis including those patients who actually received chemotherapy (n = 72), the absence of MGMT expression was independently associated with better survival (hazard ratio, 2.12; P = 0.027). MGMT promoter methylation was observed in 50% of the analyzed tumors. No statistical correlation between MGMT expression and MGMT promoter hypermethylation was observed. CONCLUSIONS: Unlike previous studies, we did not find a correlation between MGMT promoter methylation and survival. However, we observed a correlation between MGMT protein expression and survival in those patients who received chemotherapy thus suggesting that the absence of MGMT expression is a positive predictive marker in patients with anaplastic glioma.

Impact of radiotherapy delay on survival in glioblastoma.

BACKGROUND: Previous studies in glioblastoma have concluded that there is no decrease in survival with increasing time to initiation of RT up to 6 weeks after surgery. Unfortunately, the number of glioblastoma patients who start RT beyond 6 weeks is not small in some countries. The aim of our study was to evaluate the effect of RT delay beyond 6 weeks on survival of patients who have undergone completed resection of a glioblastoma. METHODS: We reviewed 107 consecutive glioblastoma patients who had a complete surgical resection at our hospital. Clinical data, including delay in initiation of RT, were prospectively collected. The impact of single parameters on overall survival was determined by univariate and multivariate analyses. RESULTS: According to univariate analysis, variables that had a prognostic influence on survival were age (p = 0.036), KPS (p = 0.031), additional treatment with CHT (p < 0.0001), and initiation of RT before 42 days (p = 0.009). Multivariate analysis indicated that Karnofsky performance scale, additional treatment with chemotherapy, and initiation of RT before 6 weeks after surgery were favorable, independent prognostic factors of survival. CONCLUSIONS: Survival is significantly reduced in glioblastoma patients if RT is not initiated within the 6 weeks after complete resection of the tumor.

Anesthetic management of a patient in prone position with a drill bit penetrating the spinal canal at C1-C2, using a laryngeal mask.

UNLABELLED: Airway management in patients with penetrating neck trauma must guarantee cervical spine stability. Moreover, the prone position increases the risk of difficult ventilation and cervical spine injury. A 19-yr-old patient was brought to the emergency room in prone position with a drill bit protruding from the posterolateral aspect of his neck. The bit had entered the spinal canal below the first cervical vertebra, and placed near the odontoid peg. He was referred for surgical removal of the drill. The use of an inhaled induction of anesthesia, avoiding muscle relaxants, and ventilation through a laryngeal mask airway inserted in the prone position seemed to offer a satisfactory approach. IMPLICATIONS: Management of patients with penetrating neck trauma must guarantee cervical spine stability. Moreover, the prone position increases the risk of difficult ventilation and cervical spine injury. Anesthesia may be induced and the airway can be managed with the patient already in the prone position for surgery.

Prognostic implication of clinical, radiologic, and pathologic features in patients with anaplastic gliomas.

BACKGROUND: The clinical evolution of anaplastic glioma (anaplastic astrocytoma, oligodendroglioma, and oligoastrocytoma) is variable. Previous studies merged patients with anaplastic glioma and the much more common glioblastoma multiforme. Therefore, the conclusions on prognostic factors reflected in part the consequences of an analysis in a heterogeneous population. METHODS: To identify clinical, neuroradiologic, pathologic, and molecular factors with prognostic significance, we analyzed 95 treated patients with a histologic diagnosis of anaplastic glioma. Variables included age, gender, clinical manifestations at diagnosis (seizures, focal neurologic deficit, and cognitive changes), computed tomographic (CT) scan characteristics (diffuse, ring, and no enhancement), tumor location, extent of resection, histopathology, postoperative Karnofsky performance status (KPS) score, adjuvant chemotherapy, tumor response, proliferation index (Ki-67 expression), and p53, p16, pRb, and epidermal growth factor receptor immunohistochemical expression. RESULTS: Ninety-five patients with a histologic diagnosis of anaplastic astrocytoma (73%), anaplastic oligoastrocytoma (16.6%), or anaplastic oligodendroglioma (10.4%) constituted the basis of this study. Median overall survival was 29 months. Multivariate analysis revealed that an age of 49 years or younger (P < 0.03), postoperative KPS score of 80 or higher (P < 0.007), absence of ring enhancement (P = 0.03), and a proliferation index of 5.1% or lower (P = 0.044) were independently associated with longer survival. The presence of an oligodendroglial component was associated with better prognosis in the univariate analysis (P = 0.009), although this lost power in the multivariate analysis. CONCLUSIONS: In addition to previously recognized prognostic variables such as age and KPS score, CT ring enhancement and tumor proliferation index were identified as independent predictors of survival in a homogeneous series of patients with anaplastic gliomas.