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Biomedical subjects

J B Posner

Publications and source records attributed to J B Posner.

At least 181 records · Page 10Linked to original sources
PubMed1981

Brachial plexus lesions in patients with cancer: 100 cases.

In patients with cancer, brachial plexus signs are usually caused by tumor infiltration or injury from radiation therapy (RT). We analyzed 100 cases of brachial plexopathy to determine which clinical criteria helped differentiate tumor from radiation injury. Seventy-eight patients had tumor (34 with previous RT), and 22 had radiation injury. Severe pain occurred in 80% of tumor patients but in only 19% of patients with radiation injury. The lower trunk (C7-8, T1) was involved in 72% of the tumors, and 32% also had epidural tumors. Seventy-eight percent of the radiation injuries affected the upper plexus (C5-6). Horner syndrome was more common in tumor, and lymphedema in radiation injury. The time from RT to onset of plexus symptoms, and the dose of RT, also differed. For symptoms within 1 year of RT, doses exceeding 6000 R were associated with radiation damage, whereas lower doses were associated with infiltration. Therefore, painless upper trunk lesions with lymphedema suggest radiation injury, and painful lower trunk lesions with Horner syndrome imply tumor infiltration.

Brachial Plexus↗
PubMed1981

Metastasis to the base of the skull: clinical findings in 43 patients.

We studied 43 patients with metastases to the base of the skull to determine whether clinical symptoms localized the lesions accurately. We identified five clinical syndromes: orbital, parasellar, middle fossa, jugular foramen, and occipital condyle. The orbital and parasellar syndromes were characterized by frontal headache, diplopia, and first-division trigeminal sensory loss. Proptosis occurred with the orbital but not the parasellar syndrome. The middle-fossa syndrome was characterized by facial pain or numbness. The jugular foramen syndrome was characterized by hoarseness and dysphagia, with paralysis of the ninth through eleventh cranial nerves. The occipital condyle syndrome was characterized by unilateral occipital pain and unilateral tongue paralysis.

Adolescent↗
PubMed1980

Radiation-induced malignant and atypical peripheral nerve sheath tumors.

The reported peripheral nerve complications of therapeutic irradiation in humans include brachial and lumbar plexus fibrosis and cranial and peripheral nerve atrophy. We have encountered 9 patients with malignant (7) and atypical (2) peripheral nerve tumors occurring in an irradiated site suggesting that such tumors represent another delayed effect of radiation treatment on peripheral nerve. The neoplasms appeared 4 to 41 years following radio-therapy, at a time when the patients (6 females and 3 males) were 16 to 70 years old and cured of their original tumors. Eight patients had received irradiation to treat malignant disease; the ninth had a benign condition. The sites of peripheral nerve tumor were the brachial plexus in 5, cervical plexus in 1, lumbar plexus in 2, and retroperitoneum in 1. Eight patients presented with painful masses, and in 6 of the 8 there was a progressive neurological deficit. Seven patients died with metastases within two years of diagnosis. In all instances the radio-therapy was within an acceptable radiation dosage, yet 3 patients developed local radiation-induced skin and bony abnormalities. In 3 patients there were either clinical signs or a family history of von Recklinghausen disease, but the malignant peripheral nerve sheath tumors developed only in the radiation port. Animal studies support the clinical observation that malignant peripheral nerve sheath tumors can occur as a delayed effect of irradiation. Other etiological mechanisms, including an increased risk of second primaries in cancer patients and a genetic predisposition to peripheral nerve tumors, may also play a role.

Adolescent↗
PubMed1980

Acute parotitis and hyperamylasemia following whole-brain radiation therapy.

Parotitis, an infrequent, previously unreported complication of whole-brain radiation therapy, was observed in 4 patients. The acute symptoms, which include fever, dry mouth, pain, swelling, and tenderness, are accompanied by hyperamylasemia. Among 10 patients receiving whole-brain irradiation, 8 had serum amylase elevations without symptoms. Both acute parotitis and asymptomatic hyperamylasemia result from irradiation of the parotid glands.

Adult↗
PubMed1980

Radiation therapy for brain metastases.

We treated 183 patients who had brain metastases with whole-brain radiation therapy (RT) and adrenocorticosteroids utilizing a new high-dose radiation protocol. Treatment produced neurological improvement in 135 patients (74%); there was no change in 37 (20%), and deterioration occurred in 11 (6%). Of those patients who improved, two-thirds maintained neurological improvement for the remainder of their lives or for at least nine months, and one-third relapsed. One-third of those who relapsed improved again with steroids or further RT. Clinical improvement paralleled tumor regression on CT scan. Despite the clinical response, median survival was only twelve weeks; 24% lived six months and 8% lived one year. Death resulted from progressive brain disease in 16% of the patients. Two-thirds of the patients died of advancing systemic disease in the setting of stable, improved neurological function. These data suggest that the majority of patients with brain metastases benefit from RT and that systemic cancer, not central nervous system disease, limits the length of life.

Adrenal Cortex Hormones↗
PubMed1980

Progressive white matter destruction following irradiation of an extracranial neoplasm.

Although numerous "cures# have been reported following surgical extirpation of symptomatic foci of cerebral radiation nerosis, delayed progressive white matter destruction and neurological deterioration may occur in some patients who survive for prolonged periods after operation. The postoperative appearance on CT scans of hypodensity within heavily irradiated white matter structures at a distance from the initial radionecrotic focus or operative site suggests continuing radiation-induced tissue injury and a poor prognosis. Anticipated survival as well as administered radiation dose must be taken into account when "safe# radiation thresholds are calculated.

Carcinoma, Squamous Cell↗
PubMed1980

Epidural spinal cord compression from metastatic tumor: results with a new treatment protocol.

Eighty-three patients with epidural spinal cord compression, from metastatic cancer were treated with high-dose adrenocorticosteroids and a new radiation fractionation protocol. Only those patients were included who had complete or almost complete block on myelography and who had not received prior radiation therapy to the area of compression. Patients were given 100 mg of dexamethasone intravenously at the time of diagnosis and 500 rads of radiation on each of the first three days. After a four-day rest, radiation therapy was continued at 300 rads to a total dose of 3,000 rads. The effects of this new protocol on the patient's motor abilities did not differ from those of previous protocols, namely, 47 of 83 patients (57%) were ambulatory after treatment, with no responses in patients totally paraplegic before treatment. However, early administration of high doses of dexamethasone substantially ameliorated pain in the majority of patients, with relief often coming within hours after the drug was given. On the basis of these data, we recommend high doses of adrenocorticosteroids combined with radiation therapy for acute treatment of spinal cord compression. The optimum fractionation schedule for radiation therapy is not established.

Adolescent↗
PubMed1980

Cerebrospinal fluid biochemical markers of central nervous system metastases.

beta-Glucuronidase and carcinoembryonic antigen (CEA) were measured in the cerebrospinal fluid of patients with cancer. Both substances were found to reliably detect the presence of leptomeningeal infiltration by carcinoma. Neither substance was reliable in the detection of leptomeningeal infiltration by lymphoma or of metastases to the brain parenchyma or spinal epidural space. beta-Glucuronidase was moderately elevated in chronic infectious meningitis, whereas CEA was not. Both markers approached control levels with favorable treatment of the leptomeningeal metastases, reflecting the effectiveness of treatment. Both beta-glucuronidase and CEA hold promise as indicators of early metastatic involvement of the leptomeninges by carcinoma.

Arachnoid↗
PubMed1980

Hypothesis: the pathogenesis of pseudotumor cerebri.

In susceptible individuals, one of a variety of known or unknown precipitants affects the arachnoid villi so as to produce a large increase in CSF outflow resistance, Ra. This increase in Ra raises CSF pressure (CSFP), which rise provokes a redistribution of arteriovenous pressures across the cerebrovascular bed. The end result is a measurable increase in cerebral blood volume, compression of the ventricular system and compromise of the convexity subarachnoid space, which further increases CSF outflow resistance. Ultimately, a new steady state CSFP is attained.

Brain Edema↗
PubMed1979

Subacute motor neuronopathy: a remote effect of lymphoma.

Ten patients developed a subacute lower motor neuron syndrome as a remote effect of Hodgkin's disease or other lymphoma. The illness usually followed a benign course independent of the activity of the underlying neoplasm. Seven of the patients improved spontaneously, and 3 became neurologically normal. Two patients died of intercurrent infections related to immunosuppression. Neuropathological examination of these 2 patients and 3 previously reported cases showed prominent neuronal degeneration restricted to the anterior horns of the spinal cord and mild posterior column demyelination. Demyelination was also present in the anterior roots of our autopsied patients and was accompanied by large, hyperchromatic Schwann cells. The cause of the illness is obscure, but both radiation therapy and opportunistic infection may be contributing factors. Attempts at virus isolation have been unsuccessful. The syndrome should be distinguished from the more common direct effects of lymphoma on the nervous system, since its identification spares the patient additional, potentially harmful therapy.

Adult↗
PubMed1979

beta-Endorphin: analgesic and hormonal effects in humans.

The pharmacokinetics and the hormonal, analgesic, and behavioral effects of several doses of human beta-endorphin were evaluated after intravenous administration to three patients and intracerebroventricular administration to one patient with pain caused by cancer. These effects were compared to the hormonal effects of intravenously administered morphine sulfate in two patients and an enkephalin analog in two baboons. The mean terminal half-life after intravenous administration of 5 or 10 mg of human beta-endorphin to three patients was 37 min; the mean volume of distribution was 178 ml/kg, and the metabolic clearance rate was 3.2 (ml/min)/kg. The half-life of beta-endorphin in cerebrospinal fluid after intracerebroventricular administration was 93 min, and the volume of distribution was 0.74 ml/kg. A rapid rise in plasma prolactin followed both intravenous and intracerebroventricular beta-endorphin. Intravenous administration did not affect plasma growth hormone, but intracerebroventricular administration suppressed plasma growth hormone. No significant change in plasma growth hormone was noted after intravenous administration of morphine to humans, but plasma growth hormone decreased in one baboon after administration of the enkephalin analog. beta-Endorphin-stimulated release of prolactin occurred at doses lower than those required to produce analgesic and other behavioral effects. When both hormonal and analgesic effects were observed (after 7.5 mg were given intracerebroventricularly), the onset of the hormonal response slightly preceded the analgesic and behavioral responses. These studies suggest that the hormonal effects of beta-endorphin are species dependent and are similar to those of morphine. Hormonal and analgesic effects of beta-endorphin appear to result from the activation of opiate receptors that differ in their locations and characteristics.

Adult↗
PubMed1979

Human brain tumor transplantation into nude mice.

Seven human brain tumors were transplanted into the brains (6/7 takes) and subcutaneous tissues (7/7 takes) of athymic nude mice. Compared to experimental animal brain tumors, these tumors, taken directly from patients in the operating room and transplanted, grew more slowly in the mice; their growth rates following explant generally paralleled those in the patients. A rough correlation was seen between the degree of the tumor's malignancy and both successful take and rate of growth following explant. The tumors' growth rates increased during serial transplantation after explant. Two tumors developed into long-term serial lines; both came from gliosarcomas. Preliminary chemotherapy experiments with these two lines demonstrated different chemosensitivities. One line was very sensitive to the nitrosoureas and resistant to procarbazine; the other line was more sensitive to procarbazine than to the nitrosoureas. This model permits study of the biologic behavior of human brain tumors growing intracerebrally and subcutaneously in nude mice.

Animals↗
PubMed1979

Malignant cells in cerebrospinal fluid (CSF): the meaning of a positive CSF cytology.

We reviewed the correlation between malignant cells in cerebrospinal fluid (CSF) (positive cytology) and pathologic findings at autopsy. The purpose was to discover: (1) the incidence of negative CSF cytology in patients with CNS malignancy, (2) the incidence of false-positive cytology, and (3) the relationship between a true-positive cytology and the distribution of malignant tumor at autopsy. Of 117 patients with CNS tumor and premortem cytologic examination of the CSF, 31 (26 percent) were positive and 86 (74 percent) were negative. Only 1 of 66 patients with tumor that did not reach the leptomeninges had a positive cytology. Of 51 patients with leptomeningeal tumor at autopsy, cytology was positive in 30 (59 percent) and negative in 21 (41 percent). Five potentially "false-positive" cytologies were encountered: three patients were treated, and tumor may have been eradicated; in two patients with lymphoma, inflammatory cells associated with infection were apparently mistaken for malignant cells. These data indicate that a positive CSF cytology is a reliable indicator of CNS malignancy and almost always reflects leptomeningeal tumor.

Brain Neoplasms↗
PubMed1979

Nonmetastatic superior sagittal sinus thrombosis complicating systemic cancer.

Seven patients with cancer complicated by nonmetastatic sagittal sinus thrombosis were encountered in a 7-year period. Five had hematologic malignancies and two had solid tumors. There were two different presentations. In the first, neurologic signs and symptoms (e.g., headaches, seizures, hemiparesis, lethargy) occurred suddenly in five patients shortly after initiation of cancer therapy. Four of these five patients recovered with minimal residua; the fifth died as a direct result of the sinus thrombosis. The second presentation occurred in the two patients with terminal cancer who declined gradually without focal signs; both patients died. Only arteriography can reliably establish the diagnosis of sagittal sinus occlusion. In patients with cancer, sagittal sinus occlusion probably results from a "hypercoagulable state" associated with the systemic neoplasm.

Adenocarcinoma↗
PubMed1979

Sterilization of cerebral metastases by radiation therapy.

It is generally acknowledged that radiation therapy (RT) provides effective palliative treatment for the majority of patients with brain metastases. It is less well known that RT can be "curative." In 10 years, we examined five patients with brain metastases treated with whole-brain radiotherapy and with no residual tumor in the brain at autopsy. These five patients represented about 3 percent (5 of 187) of patients treated for brain metastases and later examined at autopsy. Some metastatic brain tumors are eradicated by RT, and all nonterminal patients should be offered such treatment.

Adenocarcinoma↗