Convection-enhanced drug delivery of interleukin-4 Pseudomonas exotoxin (PRX321): increased distribution and magnetic resonance monitoring.

Convection-enhanced drug delivery (CED) enables achieving a drug concentration within brain tissue and brain tumors that is orders of magnitude higher than by systemic administration. Previous phase I/II clinical trials using intratumoral convection of interleukin-4 Pseudomonas exotoxin (PRX321) have demonstrated an acceptable safety and toxicity profile with promising signs of therapeutic activity. The present study was designed to assess the distribution efficiency and toxicity of this PRX321 using magnetic resonance imaging (MRI) and to test whether reformulation with increased viscosity could enhance drug distribution. Convection of low- [0.02% human serum albumin (HSA)] and high-viscosity (3% HSA) infusates mixed with gadolinium-diethylenetriamine pentaacetic acid and PRX321 were compared with low- and high-viscosity infusates without the drug, in normal rat brains. MRI was used for assessment of drug distribution and detection of early and late toxicity. Representative brain samples were subjected to histological examination. Distribution volumes calculated from the magnetic resonance images showed that the average distribution of 0.02% HSA was larger than that of 0.02% HSA with PRX321 by a factor of 1.98 (p < 0.02). CED of 3.0% HSA, with or without PRX321, tripled the volume of distribution compared with 0.02% HSA with PRX321 (p < 0.015). No drug-related toxicity was detected. These results suggest that the impeded convection of the PRX321 infusate used in previous clinical trials can be reversed by increasing infusate viscosity and lead to tripling of the volume of distribution. This effect was not associated with any detectable toxicity. A similar capability to reverse impeded convection was also demonstrated in a CED model using acetic acid. These results will be implemented in an upcoming phase IIb PRX321 CED trial with a high-viscosity infusate.

Elevated expression of the CC chemokine regulated on activation, normal T cell expressed and secreted (RANTES) in advanced breast carcinoma.

Breast carcinoma is the most common malignant disease among women and the second most lethal one. In search for a better understanding of the role of cellular mediators in the progression of this disease, we investigated the potential involvement of the CC chemokine Regulated on Activation, Normal T Cell Expressed and Secreted (RANTES) in breast carcinoma progression. To this end, RANTES expression was determined in breast tumor cell lines and in sections of breast carcinomas, followed by analysis of the incidence and intensity of its expression in different stages of the disease. Our study reveals that high and physiologically relevant levels of RANTES are constitutively produced by T47D and MCF-7 breast tumor cell lines. Analysis of RANTES expression in sections of breast carcinomas demonstrates a high incidence of RANTES expression in epithelial tumor cells; the chemokine was expressed in 74% of the sections. RANTES expression was rarely detected in normal duct epithelial cells or in epithelial cells that constitute benign breast lumps, which were located in proximity to tumor cells. High incidence and intensity of RANTES expression were detected in sections of most of the patients with stage II and stage III of the disease (expression was detected in 83 and 83.3%, respectively), whereas RANTES was expressed at a lower incidence and intensity in sections of patients with stage I of breast carcinoma (55% of the cases). Most importantly, the expression of RANTES was minimally detected in sections of patients diagnosed with benign breast disorders and of women that underwent reduction mammoplasty (15.4% of the cases). These results indicate that the expression of RANTES is directly correlated with a more advanced stage of disease, suggesting that RANTES may be involved in breast cancer progression. Moreover, it is possible that in patients diagnosed with benign breast disorders, RANTES expression may be indicative of an ongoing, but as yet undetectable, malignant process.

Monitoring response to convection-enhanced taxol delivery in brain tumor patients using diffusion-weighted magnetic resonance imaging.

Convection-enhanced drug delivery (CEDD) is a novel approach to enhance the delivery of drugs directly into brain tumors. We have used diffusion-weighted MRI (DWMRI) to monitor the effects of intratumoral CEDD in three brain tumor patients treated with Taxol. Clear changes in the images and the water diffusion parameters were observed shortly after the initiation of treatment. Initially, a bright area corresponding to decreased diffusion appeared, followed by the appearance of a dark area of increased diffusion within the bright area. The time to appearance of the dark area varied among the patients, suggesting different response rates. In this work, we have demonstrated the feasibility of using DWMRI as a noninvasive tool to achieve unique early tissue characterization not attainable by other conventional imaging methods.

Early Biomarkers from Conventional and Delayed-Contrast MRI to Predict the Response to Bevacizumab in Recurrent High-Grade Gliomas.

BACKGROUND AND PURPOSE: The interpretation of the radiologic response of bevacizumab-treated patients with recurrent high-grade gliomas represents a unique challenge. Delayed-contrast MR imaging was recently introduced for calculating treatment-response-assessment maps in patients with brain tumors, providing clear separation between active tumor and treatment effects. We studied the application of standard and delayed-contrast MR imaging for assessing and predicting the response to bevacizumab. MATERIALS AND METHODS: Twenty-four patients with recurrent high-grade gliomas were scanned before and during bevacizumab treatment by standard and delayed-contrast MR imaging. The mean change in lesion volumes of responders (overall survival, ≥1 year) and nonresponders (overall survival, <1 year) was studied. The lesion volumes at baseline and the changes in lesion volumes 1 month after treatment initiation, calculated from standard and delayed-contrast MRIs, were studied as possible predictors of outcome. In scans acquired at progression, the average change in lesion volume from previous follow-up in standard and delayed-contrast MRIs was compared. RESULTS: Response and progression patterns were identified from the mean change in lesion volumes, depicted from conventional T1WI, delayed contrast-enhanced MR imaging, and DSC MR imaging. Thresholds for early prediction of response were calculated by using these sequences. For each predictor, sensitivity, specificity, positive predictive values, and negative predictive values were calculated, reaching 85.7%, 87.5%, 75%, and 93.3% for conventional T1WI; 100%, 87.5%, 77.8%, and 100% for delayed-contrast MR imaging; and 75%, 78.6%, 50%, and 91.7% for DSC MR imaging. The benefit of delayed-contrast MR imaging in separating responders and nonresponders was further confirmed by using log-rank tests (conventional T1WI, P = .0022; delayed-contrast MR imaging, P < .0001; DSC MR imaging, P = .0232) and receiver operating characteristic analyses. At progression, the increase in lesion volumes in delayed-contrast MR imaging was 37.5% higher than the increase in conventional T1WI (P < .01); these findings suggest that progression may be depicted more effectively in treatment-response-assessment maps. CONCLUSIONS: The benefit of contrast-enhanced MR imaging for assessing and predicting the response to bevacizumab was demonstrated. The increased sensitivity of the treatment-response-assessment maps reflects their potential contribution to the management of bevacizumab-treated patients with recurrent high-grade glioma.

Intracoronary injection of basic fibroblast growth factor enhances angiogenesis in infarcted swine myocardium.

OBJECTIVES: This study was performed to examine the effect of intracoronary exogenous basic fibroblast growth factor (bFGF) on angiogenesis in infarcted myocardial regions. BACKGROUND: Exogenous bFGF is a potent promoter of angiogenesis. Little information is available on its effect on myocardial angiogenesis. METHODS: Myocardial infarction was induced in 10 pigs by intracoronary injection of microscopic beads. Four pigs served as a control group; in six pigs slow-release bFGF was delivered by the beads. Cardiac performance was evaluated by repeated echocardiographic measurement and angiogenesis was evaluated by immunohistochemical studies 14 days later. RESULTS: As compared with control pigs, pigs treated with bFGF had higher microvessel counts (mean +/- SEM) in both viable tissue (141 +/- 27 per field vs. 39 +/- 4, p = 0.01) and nonviable tissue (329 +/- 26 per field vs. 95 +/- 7, p < 0.001) within the infarct area. No significant differences in total regional left ventricular wall motion were noted between the two groups throughout the 14-day study period. CONCLUSIONS: In the swine, direct intracoronary application of bFGF to infarcted myocardium enhances myocardial neovascularization within 2 weeks.

Carcinoid tumors frequently display genetic abnormalities involving chromosome 11.

Carcinoid tumors are neuroendocrine neoplasms that are encountered either sporadically or as part of a familial syndrome, most notably-multiple endocrine neoplasia type 1 (MEN1). The MEN1 gene localizes to chromosome 11 (11q13) and presumably functions as a tumor suppressor gene. The molecular mechanisms underlying carcinoid tumor development and their clonal composition remain largely unknown. To establish whether carcinoid tumors develop via a mechanism similar to other MEN1-associated tumors, and indirectly determine their clonal composition, we analyzed 36 sporadically occurring carcinoid tumors with 16 chromosome 11 microsatellite markers, mostly from around the MEN1 region for loss of heterozygosity (LOH). Twenty one tumors (58%) displayed LOH of at least three markers, five lost almost an entire allele and the rest displayed a discontinuous pattern. Similar, but less extensive analysis was also carried out for 10 additional carcinoid tumors from Brazil, 6 of the 10 showed LOH with at least one marker. Overall, 36 of 46 tumors (78%) displayed LOH. In addition, 20 of 46 (43%) tumors exhibited a pattern of genomic instability. Thus, the majority of sporadically occurring carcinoid tumors are monoclonal whose tumorigenesis involves inactivation of a tumor suppressor gene on chromosome 11 and DNA mismatch repair genes mutations.

Ovarian hyperstimulation without elevated serum estradiol associated with pure follicle-stimulating hormone-secreting pituitary adenoma.

We report a unique case of a 28-yr-old woman with a gonadotroph adenoma secreting FSH, presented with ovarian hyperstimulation, without elevation of serum estradiol. She presented with abdominal pain and large ovaries (both 10 cm in diameter) with multiple follicular cysts shortly after discontinuing oral contraceptive pills. She had a supranormal PRL level of 71 microg/liter (normal, <20), FSH of 8.4-9.2 IU/liter (normal for follicular phase, 2.4-10), LH of 0.01 IU/liter (normal, 1.6-9.3), estradiol of 108 pmol/liter (normal for follicular phase, 80-790), and free alpha-subunit level of 0.11 microg/liter (normal, <1.8). A nuclear magnetic resonance study revealed invasive pituitary macroadenoma, 30 mm in diameter. Dopamine agonist (cabergoline) treatment normalized serum PRL but had no affect on FSH levels. A transsphenoidal surgery was performed, and most of the adenoma was resected. One month after surgery the patient resumed menstruation, and the hormonal profile included serum FSH of 6.3 IU/liter, LH of 2.1 IU/liter, estradiol of 156 pmol/liter, and PRL of 10 microg/liter. The excised adenoma tissue exhibited intense immunostaining for FSH and secreted this hormone to culture medium. Stimulation with TRH (both in vivo preoperatively and in vitro study of the excised tumor) had no effect on FSH secretion from the adenoma. Estradiol did not suppress FSH release from cultured adenoma cells. Patient serum samples showed significant FSH bioactivity when tested in a human granulosa cell line. This case is remarkable because the ovarian hyperstimulation related to the FSH-secreting adenoma was not associated with high levels of serum estradiol, probably due to insufficient LH production by the normal pituitary. Thus, it supports the two-cell, two-gonadotropin theory, that both FSH and LH are necessary for normal ovarian estrogen production.

Another complication of thoracostomy--perforation of the right atrium.

Tube thoracostomy is an invasive procedure that is frequently life-saving but carries a risk of complications. We describe herein a complication not documented before-laceration of the right atrium. This occurred in a severely kyphoscoliotic patient with a markedly narrowed chest and led to his demise. This case attests to the extreme caution warranted when using trocar-type thoracostomy in patients with thoracic deformities.

CD44 expression in normal adrenal tissue and adrenal tumours.

BACKGROUND: CD44 is a cell surface glycoprotein found on many normal cells, mainly lymphoid and epithelial. Normal cells usually express standard CD44 (CD44-S), whereas malignant tumours may express CD44 variant isoforms (CD44-V). CD44 expression has been described for neural crest derivatives. Characterisation of differences in CD44 expression may help in the diagnosis and differentiation of distinct adrenal tumours. AIMS: To examine CD44 expression in different layers of cortical cortex, in adrenal medulla, and in adrenal tumours. METHODS: CD44-S and CD44-V6 expression were studied in 12 cases of adrenal cortical adenoma, 3 of adrenal cortical carcinoma, 10 of pheochromocytoma, and 4 normal adrenal glands. RESULTS: CD44-V6 staining showed cytoplasmic expression in normal adrenal cortex and in cortical adenomas and carcinomas. Pheochromocytomas also showed CD44-V6 expression but in 5 of the 10 cases it was sparse, focal, and sometimes perinuclear. Strong membranous staining for CD44-S was observed in normal adrenal medulla. Analysis of CD44-S expression revealed differences between cortical adrenal tumours and pheochromocytomas. Ten of 12 cortical adenomas and 2 of 3 cortical carcinoma cells showed weak to moderate cytoplasmic staining, but all cases of pheochromocytoma had strong membranous staining. CONCLUSIONS: Membranous CD44-S staining may help to distinguish pheochromocytoma from adrenal cortical adenoma.

Traumatic intratumoral hemorrhage as the presenting symptom of a spinal neurinoma. Case report.

Intratumoral hemorrhage as the presenting symptom of spinal tumors is rare. The authors describe a patient who presented with rapidly progressing paraplegia 24 hours after sustaining a minor traumatic injury of the thoracic spine. Radiological evaluation demonstrated a low-thoracic intradural tumor that was resected and found to be a neurinoma in which severe intra- and peritumoral hemorrhage was revealed. The radiological, surgical, and pathological findings are presented and discussed.

Laminin alpha2 deficient congenital muscular dystrophy: prenatal diagnosis.

Laminin alpha2 chain-deficient congenital muscular dystrophy (CMD) is diagnosed by genetic analysis and by immunohistochemistry. Since laminin alpha2 chain is expressed in placental trophoblasts, the demonstration of its deficiency in chorionic villi is a useful aid to prenatal diagnosis. We present our experience with the use of the immunohistochemical method for prenatal diagnosis in four women, all of whom had at least one child with laminin alpha2 chain-deficient CMD. Immunohistochemistry provided a rapid procedure for prenatal diagnosis, and follow-up of these four cases confirmed its reliability.

Intraarterial delivery of genetic vectors for the treatment of malignant brain tumors.

BACKGROUND: The transfer of therapeutic genes into malignant brain tumors has been the subject of intense preclinical and clinical research in recent years. Most approaches have used direct intratumoral placement of a variety of vectors and genes, such as retroviruses or adenoviruses carrying drug-susceptibility genes, modified replication-competent herpes virus, and several vectors carrying tumor suppressor genes such as the p53 gene. However, clinical results have so far been disappointing, mainly due to the limited ability to effectively distribute the genetic material into the target cell population. Accordingly, alternative delivery approaches into the central nervous system, e.g., intravascular, are under investigation. Genetic vectors administered intravascularly are unlikely to penetrate the blood-brain barrier and transfer a gene into brain or tumor parenchyma. However, intravascular delivery of vectors may target endothelial cells lining the blood vessels of the brain. Since endothelial cells participate in a variety of physiological and pathological processes in the brain, their modulation by gene transfer may be used for a variety of therapeutic purposes. Angiogenically stimulated endothelial cells within tumors replicate rapidly and hence may become targets for retroviral-mediated gene transfer. OBJECTIVE: To assess the anti-tumor effect of transferring a drug-susceptibility gene into endothelial cells of the tumor vasculature. METHODS: As a model for this approach we delivered concentrated retroviral vectors carrying a drug-susceptibility gene via the internal carotid artery of rats with malignant brain tumors. The safety and efficacy of this approach, without and with subsequent treatment with a pro-drug (ganciclovir), was evaluated. RESULTS: No acute or long-term toxicity was observed after intraarterial infusion of the vector. Treatment with ganciclovir resulted in variable hemorrhagic necrosis of tumors, indicating preferential transduction of the angiogenically stimulated tumor vasculature. This was accompanied by severe toxicity caused by subarachnoid hemorrhage and intracerebral hemorrhage in vascular territories shared by the tumor and adjacent brain. CONCLUSION: The data indicate that endothelial cells can be targeted by intraarterial delivery of retroviral vectors and can be used for devising new gene therapy strategies for the treatment of brain tumors.

[Giant lesions in multiple sclerosis--a diagnostic challenge].

Multiple sclerosis is the most common demyelinating disease of the central nervous system affecting young adults, in which destruction of the axon myelin sheath disturbs signal transduction. The disease course is usually remitting and relapsing, but sometimes there is steady neurological deterioration. The diagnosis depends mainly on an adequate clinical history and neurological examination. Evoked potentials, elevated cerebrospinal fluid gamma globulin with oligoclonal bands, and imaging studies, mainly magnetic resonance imaging (MRI), also contribute to the diagnosis. Multiple sclerosis may occasionally present as a mass lesion that clinically and radiologically is indistinguishable from a brain tumor. We present 2 cases of giant tumefactive lesions, proven by brain biopsy to be of demyelinating nature.

[Tonsillar lymphoma].

3 patients with tonsillar lymphoma are described (a man of 68 and women of 62 and 57 years, respectively). The first had intermediate grade lymphoma localized in the tonsil and was treated by tonsillectomy and combined systemic chemotherapy. The second had low-grade lymphoma of the tonsil and widespread involvement of lymphoid tissue in the liver, spleen, mediastinum and retroperitoneum for which chemotherapy was given. The last had intermediate grade lymphoma, but had been misdiagnosed 4 years before as an undifferentiated carcinoma of the tonsil and was irradiated. After the malignant process had extended to the stomach, the correct diagnosis of diffuse large-cell lymphoma was made. Subtotal gastrectomy was followed by combined systemic chemotherapy. All patients responded well to treatment.

[Extraskeletal Ewing's sarcoma].

5 patients diagnosed as having extraskeletal Ewing's sarcoma have been referred to our adult oncology unit since 1980. All were men, ranging in age from 18-57 (mean 32 years). The primary tumor was located on the trunk in 4 and in an extremity in 1. Wide tumor excision was feasible in only 2. 3 died within 27 months and 2 are alive, 13 and 67 months, respectively, following diagnosis. This study demonstrates the highly aggressive nature of extraskeletal Ewing's sarcoma and the need for early diagnosis and efficient chemotherapy.

[Endometriosis of the bladder].

We report a case of endometriosis of the bladder in a 32-year-old healthy woman suffering from longstanding suprapubic pain, and urinary urgency and frequency. The disease, which is uncommon, usually has a high morbidity rate and is difficult to diagnose. A high level of suspicion is necessary for diagnosis, since neither the clinical presentation, nor imaging procedures are pathognomonic for endometriosis.

[An unusual case of subacute sclerosing panencephalitis].

A 25-year-old man was admitted following deterioration in behavior and onset of blindness. He soon became comatose and died 6 weeks later. Brain biopsy showed nuclear inclusion bodies resembling viral capsids, astrocytosis and perivascular lymphocytic cuffing but no demyelination. The diagnosis of subacute sclerosing panencephalitis was made on finding: measles virus antigens in both serum and cerebrospinal fluid, the identification of measles RNA sequences in brain tissue by the polymerase chain reaction, and intense, oligoclonal, IgG-banding in the CSF. However, the relatively advanced age of the patient, the absence of myoclonus and the nondistinctive EEG profile lacking synchronous bursts of high-voltage slow and sharp waves, are unusual.