Clinicopathological study of oligodendroglial tumors: the effectiveness of interferon beta, ACNU/MCNU, and radiation (IAR/IMR) for anaplastic tumors

Forced Gazing: A Stimulus-bound Behavior

We studied four patients with acquired brain injury who were compelled to gaze at a moving object or the face of an individual who came into their sight, especially the person's eyes. The patients continued to gaze at the object or person until it disappeared from their sight. This behavior, referred to as forced gazing, is related to visual groping (part of the instinctive grasp reaction), and, together with a similar sign of visual grasping, constitutes a spectrum of visual stimulus-bound behaviors. In addition to forced gazing, the patients exhibited a primitive reflex such as a grasp or sucking reflex. Each of the patients had lesions in the bilateral frontal lobes of the brain. We considered forced gazing to be a stimulus-bound behavior, in which patients become extremely dependent on a specific external stimulus. As gaze-related communication is considered one of the bases of an infant's social development, forced gazing may have its basis in innate human behavior that might manifest itself under specific pathological circumstances such as bilateral frontal-lobe damage.

Induction of apoptosis in glioma cells and upregulation of Fas expression using the human interferon-β gene

We investigated whether IFN-β inhibits the growth of human malignant glioma and induces glioma cell apoptosis using the human IFN-β gene transfected into glioma cells. A eukaryonic expression vector (pSV2IFNβ) for IFN-β was transfected into the glioma cell line SHG44 using liposome transfection. Stable transfection and IFN-β expression were confirmed using an enzyme-linked immunosorbent assay (ELISA). Cell apoptosis was also assessed by Hoechst staining and electron microscopy. In vivo experiments were used to establish a SHG44 glioma model in nude mice. Liposomes containing the human IFN-β gene were injected into the SHG44 glioma of nude mice to observe glioma growth and calculate tumor size. Fas expression was evaluated using immunohistochemistry. The IFN-β gene was successfully transfected and expressed in the SHG44 glioma cells in vitro. A significant difference in the number of apoptotic cells was observed between transfected and non- transfected cells. Glioma growth in nude mice was inhibited in vivo, with significant induction of apoptosis. Fas expression was also elevated. The IFN-β gene induces apoptosis in glioma cells, possibly through upregulation of Fas. The IFN-β gene modulation in the Fas pathway and apoptosis in glioma cells may be important for the treatment of gliomas.

Fractionated stereotactic radiation therapy in the management of primary oligodendroglioma and oligoastrocytoma

PURPOSE

To retrospectively analyze the outcomes and benefits from radiation therapy (RT) as a component of multimodal treatment for oligodendroglioma and oligoastrocytoma, assessing local control and survival rates and evaluating prognostic factors.

METHODS AND MATERIALS

We retrospectively reviewed 56 adult patients with supratentorial oligodendroglioma or oligoastrocytoma treated at our institution from January 1990 to December 2003 with fractionated stereotactic RT (FSRT).

RESULTS

Fractionated stereotactic RT was well tolerated in all patients, without side effects. Median survival and progression-free survival calculated from the initiation of radiotherapy were 48 months (range, 2-133 months) and 38 months (range, 2-132 months), respectively. Progression-free survival rates after radiation were 89% at 1 year and 52% at 5 years. Of 26 recurrences, 92% developed in field. With regard to histology, overall survival rates in the World Health Organization (WHO) Grade II group were 89% and 74% at 5 and 10 years, respectively. In patients with WHO Grade III tumors, overall survival rates at 5 and 10 years were 69% and 46%, respectively. No prognosticators could be identified for median survival and progression-free survival after radiotherapy. Median overall survival calculated from primary diagnosis was 77.5 months (range, 3-214 months). The Cox regression multivariate analysis for age and neurologic symptoms showed a significance of p = 0.003 for age and p = 0.037 for the presence of neurologic symptoms on overall survival since primary diagnosis.

CONCLUSIONS

Commonly, conventional conformal RT is applied in the treatment of brain tumors. In FSRT, the tumor volume can be irradiated with high doses, sparing volume of normal brain tissue. Our data are in accordance with survival times found in the literature. Ninety-two percent of all recurrences occurred within the defined target volume, confirming that reduction of the RT portals by the use of FSRT does not lead to an increased rate of recurrences at the field border or out of field. Fractionated stereotactic RT can therefore be implemented as an effective and safe modality in the therapy of primary oligodendroglioma and oligoastrocytoma.

Oligodendroglioma and anaplastic oligodendroglioma:

BACKGROUND

Recent advances that have been made in diagnostic imaging, surgical technique, chemotherapy, molecular biology, and prediction of therapeutic response could have potential impact on the optimal diagnosis and treatment of patients with brain tumors, especially those with oligodendrogliomas. In this article, the topic of oligodendroglioma and anaplastic oligodendroglioma is reviewed, highlighting the new clinical developments.

METHODS

Information for this review was obtained by performing a Medline search for recent references using the term "oligodendroglioma." The bibliographies of papers obtained also were checked for articles that could provide additional understanding of this disease and its current treatment.

RESULTS

The incidence of oligodendroglioma is increasing, most likely due to its improved recognition. Seizures and/or headaches are still common presenting features, and surgery continues to be the primary treatment. Positron emission tomography (PET) and molecular analysis of the surgical specimen are emerging as important diagnostic tools. Patients having either oligodendroglioma or anaplastic oligodendroglioma are likely to respond to chemotherapy. This has had an impact upon the timing of radiation therapy. Survival times are increasing, and patients can now be divided into prognostic subgroups based on the molecular features of their tumors. While procarbazine-CCNU-vincristine (PCV) chemotherapy has been the standard, other agents, notably temozolomide, are currently being tested.

CONCLUSIONS

The algorithm for diagnosing and treating patients with oligodendrogliomas has changed. Neurosurgeons need to be aware of the new developments so they can offer sound advice to their patients.

Posterior fossa oligodendroglioma

Oligodendroglioma are the tumors of glial cells. They are rare in children and are more common in the cerebral hemispheres. A rare case of infratentorial oligodendroglioma in a female child is being reported here.

Efficacy of adjuvant therapy with procarbazine, MCNU, and vincristine for oligodendroglial tumors

An adjuvant chemotherapy regimen consisting of procarbazine, MCNU, and vincristine (PMV) was evaluated for the treatment of malignant oligodendroglial tumors. Ten patients with histologically proven oligodendroglial tumors were treated with PMV therapy and the effectiveness was assessed using magnetic resonance imaging. Four patients with primary tumors underwent PMV after radiation therapy, and six patients with recurrent tumors were treated using PMV only. Tumor response was defined as radiological evidence of mass size change after completion of three courses of PMV. Complete or partial responses (more than 50% reduction in tumor mass) were noted in six patients, and tumor growth stabilized in four patients. In particular, inhibition of tumor growth using PMV was achieved in three patients with recurrent oligodendroglial tumors, despite the initial response after chemoradiation therapy (interferon-beta, MCNU, radiation) or nitrosourea chemotherapy (ACNU, MCNU). This PMV regimen (a modified PCV regimen using drugs available in Japan) is effective for treating malignant oligodendroglial tumors despite recurrence after other initial treatment procedures.