Michael Salcman

Hyperthermia for brain tumors: biophysical rationale.

Hyperthermia has great potential as an antineoplastic agent because: (a) it is effective against relatively radioresistant hypoxic cells and cells in S phase; (b) unlike most chemotherapeutic agents, it is effective against poorly vascularized and metabolically quiescent tissues; (c) as a physical agent, its biological effect is related to the duration and intensity of its application; (d) it seems to have no cumulative toxicity; and (e) it potentiates the effects of both chemotherapy and ionizing radiation at the cellular level. The use of hyperthermia for malignant brain tumors is constrained by a relatively narrow therapeutic index and the considerable thermal sensitivity of normal neural tissue. Glioblastoma multiforme, by virtue of its low growth fraction and heterogeneous cell populations, seems to be an ideal candidate for hyperthermia administered as part of a combined modality treatment program. Focal hyperthermia can be produced by a number of energy sources, including those utilizing ultrasound, microwave, and radiofrequency generators. The clinical safety and feasibility of a miniature microwave radiator/sensor system for direct implantation have been demonstrated. In comparison to normal feline brain, malignant brain tumors in humans are unable to dissipate heat efficiently.

Neurosarcoidosis: A review of the rarer manifestations

Neurosarcoidosis characteristically presents with the onset of cranial nerve palsies or endocrine and electrolyte disturbances in a patient with known systemic sarcoid. However, the disease may occasionally manifest itself in patients with no evidence of somatic involvement and with a variety of neurological signs and symptoms. We present two cases that demonstrate several of the rare manifestations of the illness and review the literature on the diagnosis and treatment.

Survival in GlioblastomaHistorical Perspective

The accumulated retrospective experience with glioblastoma multiforme was reviewed. Data were extracted from 17 reports in the literature, comprising 2532 patients. Survival curves were constructed for 1561 selected cases that did not include limited surgery and/or astrocytoma Grade III. The median

Multiple intracerebral arteriovenous malformations: Report of three cases and review of the literature

Multiple intracerebral arteriovenous malformations are thought to be exceedingly rare lesions and have usually been reported as single cases. During the past 2 years, we have treated three patients with multiple cerebral arteriovenous malformations, representing 3.2% of a consecutive series of 95 arteriovenous malformation patients seen since 1976. Details on 17 other cases are available in the literature and are summarized here. The incidence of multiple arteriovenous malformations in major series ranges from 0.3% to 3.2%; the average incidence is 1.9% based on 21 cases encountered in a total population of 1102 arteriovenous malformation patients. Patients with multiple arteriovenous malformations often have other vascular anomalies of the brain or soft tissues, but the clinical mode of presentation, age, sex, and anatomical distribution of the lesions are the same as those of patients with single arteriovenous malformations. The use of four-vessel angiography in combination with magnetic resonance imaging may result in a higher detection rate for such cases.

Primitive neuroectodermal tumor in a 57-year-old man

Primitive neuroectodermal tumors are rare cerebral neoplasms previously described only in children and young adults. This report describes such a tumor arising in the left frontal lobe of a 57-year-old man. After surgical resection and radiation therapy to the primary site, the patient developed extensive central nervous system metastases that led to his death. The histopathologic, radiographic, and clinical features of this case suggest that future therapeutic protocols for primitive neuroectodermal tumor should be similar to those for childhood medulloblastoma or neuroblastoma.

Giant posttraumatic aneurysm of the intracranial carotid artery: evolution and regression documented by computed tomography.

Posttraumatic aneurysms of the proximal intracranial internal carotid artery are rare. A case is presented in which the evolution and regression of such an aneurysm is documented by computed tomography as well as by arteriography. The coexistence of a proximal dissection of the cervical carotid artery probably contributed to the growth of the aneurysm.

Occurrence of glioblastoma multiforme in three generations of a cancer family.

We report a cancer family in which glioblastoma multiforme occurred in each of three successive generations and strictly in the paternal lineage. The pedigree is consistent with an autosomal-dominant pattern of inheritance, and this conclusion is supported by the incidence of other tumors within the family. Ten of the 23 blood relations of the proband have developed cancers (43.5%), and 5 of these have been breast carcinomas. The clinical importance of the cancer family syndrome is discussed, as is the relevance of genetic factors in the expression of the neoplastic phenotype.

A multiple floating microelectrode for chronic implantation and longterm single unit recording in the cat

This paper describes a multiple electrode, suitable for chronic implantation and single unit recording in the superficial cerebral cortex of the cat. The electrodes are fine wires, 5-8 per implant, not kept together in a bundle; a segment of them floats freely in saline in a closed chamber over the place of penetration. The electrode tips are not sharpened electrolytically, but cut at a bevel during surgery. Longevity of the implants is improved by slowing down the occasional rapid head shaking characteristic of cats, which tends to tear out implanted electrodes, by means of a small weight attached by a bar to the head.

Arteriovenous Malformations of the Superior Cerebellar Artery: Excision via an Occipital Transtentorial Approach

Arteriovenous malformations (AVMs) of the superior cerebellar artery (SCA) are unusual and difficult lesions to treat, representing less than half of all AVMs located in the posterior fossa. Traditional approaches for surgical extirpation include the subtemporal transtentorial and suboccipital supracerebellar routes. On the basis of our recent experience with three SCA-supplied AVMs, we advocate an occipital transtentorial approach similar to that used for neoplasms of the pineal gland. Exposure of the AVM from above and in the midline provides superior visualization of the deep veins, the SCA arborization in the retrocollicular space, and the rostral cerebellum, without exposing the temporal lobe and the 4th nerve to surgical trauma in a narrow, confined space. Superior cerebellar AVMs that arise from the caudal branch of the SCA on the superolateral aspect of the hemisphere are more easily handled by standard suboccipital methods.

Laser microsurgery: A review of 105 intracranial tumors

The relative importance or utility of the carbon dioxide laser within the total context of multimodality therapy and in comparison to conventional surgical techniques is unknown. Over a 36 month period, 421 operations for tumors of the brain and spinal cord were performed in our clinic. Of these, 111 (26%) were carried out with the aid of the laser. After excluding stereotactic and transsphenoidal operations, a comparison was made between 105 laser and 216 non-laser craniotomies. With the exception of pituitary tumors, the most frequent diagnoses in both the laser and non-laser cases were the same: malignant astrocytoma (48.6 vs 33.9%), meningioma (11.4 vs 14.2%) and low grade astrocytoma (8.6 vs 8.7%). The number of reoperations in the laser group (60.1%) was higher than in the non-laser group (32.7%; p < 0.000001) and the mean operating time (299 minutes vs 237 minutes; p < 0.00001) was longer, but there was no significant mean difference in mortality, CNS morbidity, mean blood loss (638 ml vs 671 ml) or mean length of stay (23 vs 25 days). For the subgroup of 134 cases of malignant astrocytoma, 82% of laser procedures were reoperations versus 50% for non-laser cases (p < 0.0002) and the mean operating time was slightly longer (p < 0.02). The length of stay for laser cases tended to be less (21 vs 27 days; p < 0.04), but there was again no difference in blood loss (457 ml vs 522 ml), CNS morbidity (7.8 vs 4.8%) or mortality. We conclude that the essential equivalence in outcomes, despite a higher number of reoperations and difficult benign tumors in the laser group, may indicate the usefulness of the laser but that less than 25% of all tumor patients will benefit from this surgical tool. It is not possible to statistically demonstrate the benefits of laser surgery by standard measures of outcome.