Kenji Muro

Progressive multifocal leukoencephalopathy after rituximab therapy in HIV-negative patients: a report of 57 cases from the Research on Adverse Drug Events and Reports project

Rituximab improves outcomes for persons with lymphoproliferative disorders and is increasingly used to treat immune-mediated illnesses. Recent reports describe 2 patients with systemic lupus erythematosus and 1 with rheumatoid arthritis who developed progressive multifocal leukoencephalopathy (PML) after rituximab treatment. We reviewed PML case descriptions among patients treated with rituximab from the Food and Drug Administration, the manufacturer, physicians, and a literature review from 1997 to 2008. Overall, 52 patients with lymphoproliferative disorders, 2 patients with systemic lupus erythematosus, 1 patient with rheumatoid arthritis, 1 patient with an idiopathic autoimmune pancytopenia, and 1 patient with immune thrombocytopenia developed PML after treatment with rituximab and other agents. Other treatments included hematopoietic stem cell transplantation (7 patients), purine analogs (26 patients), or alkylating agents (39 patients). One patient with an autoimmune hemolytic anemia developed PML after treatment with corticosteroids and rituximab, and 1 patient with an autoimmune pancytopenia developed PML after treatment with corticosteroids, azathioprine, and rituximab. Median time from last rituximab dose to PML diagnosis was 5.5 months. Median time to death after PML diagnosis was 2.0 months. The case-fatality rate was 90%. Awareness is needed of the potential for PML among rituximab-treated persons.

A phase 2 trial of single‐agent bevacizumab given in an every‐3‐week schedule for patients with recurrent high‐grade gliomas

The authors evaluated a 3‐week schedule of bevacizumab in patients with recurrent high‐grade glioma (HGG).

Preoperative Onyx Embolization of Aggressive Vertebral Hemangiomas

SUMMARY: We report the first use of Onyx in the embolization of spinal tumors in 2 cases of aggressive vertebral hemangioma. In both cases, Onyx embolization provided effective preoperative tumor devascularization after the initial prolonged particulate embolization with Embospheres made little overall impact. Onyx enables a more rapid and visible embolization than particles and is less technically demanding than traditional liquid embolic agents, such as n-butyl cyanoacrylate.

The use of infraorbital nerve block for postoperative pain control after transsphenoidal hypophysectomy

Objectives: The transsphenoidal approach for pituitary resection is often used for a suprasellar tumor. The use of infraorbital nerve block for pain control in the postoperative period is described in this case report. Case report: An 11-year old male was scheduled for a transsphenoidal approach to a pituitary tumor. After induction of general anesthesia and placement of an endotracheal tube, bilateral infraorbital nerve blocks (maxillary division of the trigeminal nerve) were performed using an intraoral approach. This block was repeated at the conclusion of surgery. The patient was very comfortable in the postoperative period without need for additional analgesia. Conclusions: Bilateral infraorbital nerve blocks may provide adequate pain control following transsphenoidal hypophysectomy. The avoidance of opoids may allow better neurological examination following major neurosurgical procedures.

Convection-Enhanced and Local Delivery of Targeted Cytotoxins in the Treatment of Malignant Gliomas

Despite advances in our knowledge about the genesis, molecular biology, and natural history of malignant gliomas and the use of a multi-disciplinary approach to their treatment, patients harboring this diagnosis continue to face a grim prognosis. At the time of diagnosis, patients typically undergo surgery for the establishment of a histologic diagnosis, the reduction of tumor burden, and the relief of mass effect, with the maintenance of the patients neurological function in mind. This is followed by the administration of adjuvant therapeutics, including radiation therapy and chemotherapy. Many investigational agents with laboratory evidence of efficacy against malignant gliomas have not met their promise in the clinical setting, largely due to the barriers that they must overcome to reach the tumor at a therapeutically meaningful concentration for a durable period of time. The relevant aspects of the blood-brain barrier, blood-tumor barrier, and blood-cerebrospinal fluid barrier, as they pertain to the delivery of agents to the tumor, will be discussed along with the strategies devised to circumvent them. This discussion will be followed by a description of agents currently in preclinical and clinical development, many of which are the result of intense ongoing research into the molecular biology of gliomas.

Multiple brain abscesses due to Actinomyces species

We report a case of multiple brain abscesses due to Actinomyces species in a 35-year-old immunocompetent man who presented with a 2-month history of headache, diplopia, fever, and weight loss. Despite receipt of broad-spectrum antibiotics for over a month, he continued to have headaches and diplopia. He subsequently underwent right anterior temporal lobectomy and evacuation of abscesses. The diagnosis was aided by identification of sulfur granule on histopathological examination of cerebral cavitary lesion and Gram-positive filamentous rods seen on tissue-Gram stain.

Generation of embryonic stem cells: limitations of and alternatives to inner cell mass harvest

Embryonic stem (ES) cells are pluripotent cells derived from the inner cell mass of the early mammalian embryo. Because of their plasticity and potentially unlimited capacity for self-renewal, ES cells have generated tremendous interest both as models for developmental biology and as possible tools for regenerative medicine. This excitement has been attenuated, however, by scientific, political, and ethical considerations. In this article the authors describe somatic cell nuclear transfer and transcription-induced pluripotency, 2 techniques that have been used in attempts to circumvent the need to derive ES cells by the harvest of embryonic tissue.

Chordomas of the craniospinal axis: Multimodality surgical, radiation and medical management strategies

Chordomas are neoplasms of the primitive notochord remnants and are characterized by slow growth kinetics, locally aggressive behavior and resistance to conventional therapeutic options. They are found primarily in the skull base or the sacral region, although they can occur anywhere in the craniospinal axis. If an oncologic surgical resection can be performed safely, patients derive the maximal benefit. Adjuvant radiotherapy has a proven benefit in both progression-free and overall survival. Chemotherapy plays a limited role and currently remains an option at tumor recurrence, although increasing knowledge of the molecular biology of chordomas may lead to targeted therapeutic strategies. In this review, the current multimodality treatment strategy for chordomas will be discussed and future directions will be highlighted.

True aneurysm on the posterior meningeal artery associated with a dural arteriovenous fistula: Case report

BACKGROUNDWe report an unusual case of a true dural aneurysm arising from the posterior meningeal artery that fed a symptomatic dural arteriovenous fistula located at the right transverse-sigmoid sinus junction. CLINICAL PRESENTATIONA 29-year-old right-handed white woman presented with aneurysmal dilatation of hypertrophied posterior meningeal artery feeding a partially treated dural arteriovenous fistula. INTERVENTIONThe aneurysm, which measured approximately 3 mm in width and 5 mm in length, was located in the intracranial space with a thin-walled dome projecting toward the cerebellum. Its afferent and efferent vessels were identified, secured, and the lesion was excised en bloc. CONCLUSIONA thorough evaluation of all diagnostic studies should be performed for patients with vascular malformations to help identify these or other unusual lesions that may aid in the risk stratification process and management plan.

High-grade dural arteriovenous fistula simulating a bilateral thalamic neoplasm

Dural arteriovenous fistulae (dAVF) provide a diagnostic challenge and must be part of a broad differential in pursuit of a difficult diagnosis or unusual presentation. This case report demonstrates an initially misguided diagnosis of bilateral thalamic neoplasm and demonstrates the importance of continued pursuit until the correct diagnosis is obtained. Moreover, to our knowledge, this is the first reported case of a dAVF simulating a bilateral thalamic neoplasm. We present a patient with a provisional diagnosis of bilateral thalamic neoplasm based on clinical history and an advanced imaging workup including MR spectroscopy. Subsequent biopsy suggested venous congestion, hypoxia, and edema without neoplasia. Routine post-operative CT the following day revealed suggestion of dAVF due to the presence of residual contrast from prior unrelated abdominal CT. Cerebral angiography eventually revealed a Cognard grade IIb dAVF. Trans-arterial Onyx embolization resulted in a dramatic clinical and radiographic improvement. This case highlights an unusual presentation and challenging diagnosis of a dAVF and the importance of pursuing the correct diagnosis.