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.

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.

Effects of selective somatostatin analogs and cortistatin on cell viability in cultured human non-functioning pituitary adenomas.

Clinically "non-functioning" human pituitary adenomas (NFPA) constitute about 35% of pituitary adenomas. Somatostatin receptors (SSTR) expression in these adenomas has previously been described both in vitro and in vivo, without evidence for a correlation with tumor volume or the therapeutic efficacy of somatostatin analogs. This study was performed on 13 surgically removed pituitary macroadenomas, diagnosed before surgery as "non-functioning". In addition, 3 growth hormone (GH)-secreting adenomas served as controls. A specimen from each tumor was dispersed and digested to isolate and culture the tumor cells, and the in vitro effects of SSTR2 and SSTR5 selective analogs and Cortistatin (CST) (100nM) on cell viability were studied. The quantity of viable cells was estimated using the XTT method. RNA purification of tumor samples and subsequent RT-PCR studies for SSTR2 and SSTR5 expression were performed. Somatostatin analog with high affinity for SSTR2 reduced cell viability by 20-80% in 8 of 13 NFPAs studied, all expressing the SSTR2. The inhibitory effect on cell viability of SSTR5-selective analog was 15-80% in 10 of 13 NFPAs studied, all but three expressing the SSTR5. CST, however, effectively reduced cell viability in only 6 NFPAs. Cell viability was inhibited by all peptides studied in 2 out of 3 GH-secreting adenomas, expressing both receptors. The third adenoma responded to SSTR2 analog and expressed only SSTR2. These results suggest the involvement of SSTR2 and SSTR5 in the anti-proliferative effects of somatostatin; however, CST is less potent in reducing cell viability in these tumors.

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.

Reduced expression of plakoglobin correlates with adverse outcome in patients with neuroblastoma.

Plakoglobin and its homologue beta-catenin are cytoplasmic proteins that mediate adhesive functions by interacting with cadherin receptors and signaling activities by interacting with transcription factors. It has been suggested that plakoglobin can suppress tumorigenicity whereas beta-catenin can act as an oncogene. We investigated the correlation between the expression pattern of N-cadherin, beta-catenin, and plakoglobin and tumor behavior in primary tumors of 20 neuroblastoma patients of all stages and in 11 human neuroblastoma cell lines. N-cadherin and beta-catenin were detected in 9 of 11 and 11 of 11 cell lines, respectively, whereas plakoglobin was undetectable or severely reduced in 6 of 11 cell lines. Tumor cells from 16 of 20 patients expressed N-cadherin and 20 of 20 patients expressed beta-catenin at levels similar to those of normal ganglion cells. Plakoglobin was undetectable in 9 of 20 tumors. Plakoglobin deficiency in the primary tumors was significantly associated with adverse clinical outcome. Five of the patients with plakoglobin-negative tumors died whereas four patients are alive without evident disease. In contrast, all patients with plakoglobin-positive tumors are alive; 2 of 11 are alive with the disease and 9 of 11 are alive without evident disease. These results suggest that down-regulation of plakoglobin may be of prognostic value for neuroblastoma patients as predictor of poor outcome.

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.

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.

Pituitary macroadenoma secreting thyrotropin and growth hormone: remission of bihormonal hypersecretion in response to lanreotide therapy.

We report a case of mixed TSH- and GH-secreting pituitary adenoma in a 60-year-old female patient. She presented with bitemporal hemianopsia and large invasive pituitary macroadenoma. Blood hormone levels determinations revealed elevated thyroid hormones, TSH, and IGF-1 with a relatively low GH. The patient had a mild acromegalic appearance but did not display signs of thyrotoxicosis or goiter. She underwent two pituitary surgical procedures followed by radiotherapy, but despite treatment was still hormonally active. Pathological examination of the resected tumor immunostained positively for both TSH and GH. The patient was subsequently treated with injections of lanreotide, a depot long-acting somatostatin analog, resulting in suppression of blood TSH, thyroid hormones, alpha-subunits, GH and IGF-1.

Acromegaly with normal growth hormone levels: response to Sandostatin-LAR treatment.

We report a case of acromegaly with relatively low GH secretion in a patient with GH-secreting pituitary macroadenoma. The 44-year-old male patient presented with left temporal hemianopsia and characteristic acromegalic face, but had relatively low baseline and post-glucose GH levels. IGF-1 and IGFBP-1 were elevated. Transsphenoidal surgery did not achieve clinical or biochemiacl remission, and the patient still had elevated IGF-1 levels with low GH. Histological examination of the resected tumor revealed a pituitary adenoma stained weakly for GH. The patient was treated then with monthly injections of Sandostatin-LAR, with clinical improvement and suppression of IGF-I to the normal range. This is a rare case of acromegaly without elevated GH levels, and good response to treatment with somatostatin analog, as expected in classical GH-secreting pituitary adenomas.

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.

[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.

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.

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.

Basic fibroblast growth factor induces myocardial hypertrophy following acute infarction in rats.

Basic fibroblast growth factor (bFGF) is a potent mitogen which induces growth of collateral vessels in ischaemic and infarcted myocardium. The effect of systemically administered bFGF on left ventricular (LV) function, myocardial hypertrophy and LV remodelling following acute myocardial infarction (MI) have not yet been fully investigated. Thirty Sprague-Dawley male rats were randomized to receive bFGF (0.5 mg) or rat albumin intraperitoneally for 1 week, beginning immediately after the induction of MI. Five animals served as controls and did not undergo any operation. Animals were killed 6 weeks after surgery and the hearts were perfused and fixed at physiological pressure. Transverse cross-sections from infarcted areas were stained with antibodies against proliferating cell nuclear antigen (PCNA) and Masson-trichrome and analysed with a coloured-image analyser for LV area (mm2), LV cavity diameter (mm), infarcted area (%), and wall thickness (mm) in infarcted and non-infarcted regions. LV area was similar in MI rats and in controls (41.7 +/- 6.9 and 43.0 +/- 1.5 mm2, respectively) and was significantly larger in MI bFGF-treated (MI/bFGF) animals (47.6 +/- 7.1 mm2) (P = 0.023). LV cavity diameter was significantly larger in the MI group than in MI/bFGF and control animals (6.0 +/- 0.8, 4.9 +/- 1.4, and 4.4 +/- 0.8 mm, respectively, P = 0.018). Wall thickness in the non-infarcted region was significantly smaller in MI animals (1.4 +/- 0.3 mm) than in MI/bFGF animals (1.6 +/- 0.4 mm) and the control group (1.6 +/- 0.1 mm) (P = 0.015). The ratio between LV cavity diameter/non-MI wall thickness was higher in MI than in control and MI/bFGF groups (4.8 +/- 1.6, 2.7 +/- 0.6 and 3.3 +/- 1.8, respectively, P = 0.03). Proliferating endothelial cells were significantly more abundant in infarcted than in normal areas in both MI and MI/bFGF groups, but with no significant differences between the groups. Intraperitoneal administration of bFGF did not cause any untoward extracardiac effects. Thus, systemic bFGF administration following acute MI in rats prevents dilatation of the LV, induces hypertrophy of the non-infarcted myocardium and exerts no untoward effects on extracardiac organs.

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.

Clinical-pathological study of uterine leiomyomas with high mitotic activity.

OBJECTIVE: To evaluate clinical-pathological aspects of mitotically active leiomyomas. STUDY DESIGN: Twenty patients with smooth muscle tumors of the uterus, with 5-9 mitotic figures per 10 high power fields and without atypia or necrosis were studied. The clinical and pathological characteristics of these tumors were reviewed and analyzed. RESULTS: Patients' ages ranged from 33 to 63 years (mean 42.5 years). The size of the tumors ranged from 1.5 to 9.5 cm (mean 5.4 cm). On gross examination all tumors appeared as typical leiomyomas. Treatment included hysterectomy in 16 patients and myomectomy in four. Follow-up periods ranged from 1.5 to 11 years (mean 6.8 years). None of the patients developed a recurrent tumor. CONCLUSION: The benign clinical behavior of such tumors supports their current designation as mitotically active leiomyomas, thus deleting the previous misnomer 'smooth muscle tumors of uncertain malignant potential'. Myomectomy is an appropriate treatment, particularly in young patients interested in reproduction.

An investigation of the possible neurotoxic effects of intrathecal midazolam combined with fentanyl in the rat.

In previous work, midazolam was injected intrathecally and produced reversible, segmental, spinally mediated anti-nociception sufficient for abdominal surgery in a rat model. The neurotoxic effect of midazolam, alone or combined with fentanyl, injected intrathecally repeatedly on 15 occasions over a period of 1 month, was studied in the same model. We sought to establish whether this would produce neurological damage or neurotoxic injury. Histopathological examination of the excised spinal cord and paraspinal tissues was carried out. Thirty Wistar strain rats with nylon catheters chronically implanted in the lumbar subarachnoid space were divided into five groups: group 1 (n = 6) received 40 microL of midazolam 0.1%; group 2 (n = 6) received 40 microL of fentanyl 0.005%; group 3 (n = 6) received 20 microL of midazolam 0.1% plus 20 microL of fentanyl 0.005%; group 4 (n = 6) received 40 microL of lignocaine 2%; group 5 (n = 6) received 40 microL of phenol in water. All substances were injected through the implanted catheters. The neurological recovery of all the animals in the four groups that received intrathecal midazolam alone, fentanyl alone, midazolam plus fentanyl and lignocaine alone was similar and complete. There were no significant differences in the histological changes in the neural tissues of these groups, despite repeated application of the test substances. Group 5 demonstrated the typical neurolytic lesions of phenol when injected intentionally into the subarachnoid space.