[Optical coherence tomography of bladder resection specimen]

INTRODUCTION

The diagnosis of bladder urothelial tumors is based on bladder resection and histological analysis of the specimen. The time to obtain the results of the histological analysis increases the treatment delay. Furthermore, the lack of muscle on the specimen forces the surgeon to practice on other procedure. Full field optical coherence tomography (FFOCT) is a recent imaging technique to analyze tissue. The aim of our study was to evaluate the feasibility and diagnostic accuracy of FFOCT to detect muscle and tumor in bladder resection specimen.

PATIENTS AND METHODS

We analyzed with the FFOCT technique bladder resection specimen of 24 consecutives patients. Three readers did the blind analyze of the images, looking for the presence of muscle and tumor on each specimen. Their results were compared with histological analysis to calculate diagnostic accuracy for each reader.

RESULTS

Mean sensibilities for the detection of muscle and tumor were respectively 75% and 81%. Mean specificities for the detection of muscle and tumor were respectively 78.3% and 55.3%.

CONCLUSIONS

Our results suggest that the FFOCT is feasible to analyze bladder resection specimen. Sensibilities and specificities calculated are encouraging for the detection of muscle and tumor. The accuracy of this detection and early-staging tool should be validated by larger studies.

LEVEL OF EVIDENCE

3.

[Pathological findings of visible and non-visible tumors on multiparametric magnetic resonance imaging (MRI) prior to radical prostatectomy]

INTRODUCTION

As urologists are questioned about the overtreatment of localized prostate cancer, multiparametric MRI can diagnose significant prostate cancer thanks to targeted biopsies. However, some tumors cannot be detected by MRI. What are the pathological characteristics of those tumors?

MATERIALS AND METHODS

We have selected 144 consecutive patients treated with radical prostatectomy for clinically localized prostate cancer diagnosed on systematic and targeted biopsies (Koelis^®) according to multiparametric MRI findings. On MRI, each suspicious area was graded according to the PI-RADS score v1.0. On radical prostatectomy specimen, tumor foci with a Gleason score greater than 3+3 and/or a tumor volume greater than 0,5cm³ were considered significant. The grade-four tumoral volume was calculated by multiplying the tumoral volume by grade 4 tumoral percentage.

RESULTS

Two hundred and seventy seven tumors were identified. A hundred and thirty nine were non-visible on MRI. They had a significantly lower volume (0.15cm³ versus 1.45cm³, P<0.0001) and a Gleason score significantly lower (P<0.0001) than apparent tumors. 17.3% of non-apparent tumors were significant. Moreover, the grade-four tumoral volume of significant non-apparent tumors was significantly lower than that of significant apparent tumors (0.11cm³ versus 0.66cm³, P<0.0001).

CONCLUSION

Non-apparent prostate tumors on multiparametric MRI have a Gleason score, a tumor volume - and consequently - a grade 4 tumor volume significantly lower than apparent tumors.

LEVEL OF PROOF

4.

Self-assembling peptide matrix for the prevention of esophageal stricture after endoscopic resection: a randomized controlled trial in a porcine model

Esophageal stricture formation after extensive endoscopic resection remains a major limitation of endoscopic therapy for early esophageal neoplasia. This study assessed a recently developed self-assembling peptide (SAP) matrix as a wound dressing after endoscopic resection for the prevention of esophageal stricture. Ten pigs were randomly assigned to the SAP or the control group after undergoing a 5-cm-long circumferential endoscopic submucosal dissection of the lower esophagus. Esophageal diameter on endoscopy and esophagogram, weight variation, and histological measurements of fibrosis, granulation tissue, and neoepithelium were assessed in each animal. The rate of esophageal stricture at day 14 was 40% in the SAP-treated group versus 100% in the control group (P = 0.2). Median interquartile range (IQR) esophageal diameter at day 14 was 8 mm (2.5-9) in the SAP-treated group versus 4 mm (3-4) in the control group (P = 0.13). The median (IQR) stricture indexes on esophagograms at day 14 were 0.32 (0.14-0.48) and 0.26 (0.14-0.33) in the SAP-treated and control groups, respectively (P = 0.42). Median (IQR) weight variation during the study was +0.2 (-7.4; +1.8) and -3.8 (-5.4; +0.6) in the SAP-treated and control groups, respectively (P = 0.9). Fibrosis, granulation tissue, and neoepithelium were not significantly different between the groups. The application of SAP matrix on esophageal wounds after a circumferential endoscopic submucosal dissection delayed the onset of esophageal stricture in a porcine model.

Topical hemostatic powder promotes reepithelialization and reduces scar formation after extensive esophageal mucosal resection

The development of techniques for endoscopic resection has provided new strategies for radical conservative treatment of superficial esophageal neoplasms, even those that are circumferential, such as Barrett's neoplasia. However, it is necessary to prevent the formation of scar tissue that can be responsible for esophageal strictures following circumferential resection. Preliminary data have suggested the possible efficacy of a hemostatic powder in the promotion of wound healing. The study aims to assess the effectiveness of Hemospray (Cook Medical) in a swine model of post-endoscopic esophageal stricture. Our prospective controlled study included 21 pigs. A 6-cm circumferential submucosal dissection of the esophagus (CESD) was performed in each pig. Group 1 (n = 11) only underwent CESD and Group 2 (n = 10) had repeated Hemospray applications after CESD. Clinical, endoscopic, and radiological monitoring were performed, blood levels of four inflammatory or pro-fibrotic cytokines were assessed, and histological analysis was performed. Median esophageal diameter was greater in the group treated with Hemospray (2 mm [1-3] vs. 3 mm [2-4], P = 0.01), and the rate of symptomatic esophageal stricture was 100% and 60% in Groups 1 and 2, respectively (P = 0.09). The thicknesses of esophageal fibrosis and inflammatory cell infiltrate were significantly lower in Group 2 than in Group 1 (P = 0.002 and 0.0003, respectively). The length of the neoepithelium was greater in Group 2 than in Group 1 (P = 0.0004). Transforming growth factor-β levels were significantly lower in Group 2 than in Group 1 (P = 0.01). The application of Hemospray after esophageal CESD reduces scar tissue formation and promotes reepithelialization, and therefore is a promising therapeutic approach in the prevention of post-endoscopic esophageal stricture.

Systematic review: the prevention of oesophageal stricture after endoscopic resection

BACKGROUND

Extensive endoscopic resections for the treatment of early oesophageal neoplasia can result in fibro-inflammatory strictures that require repeated interventions, which significantly alter the patients' quality of life.

AIMS

To review current evidence about the prevention of oesophageal strictures following endoscopic resections.

METHODS

Systematic search of PubMed and Embase from inception to March 2015 using appropriate keywords. All original publications in English were included, and articles on the treatment of oesophageal stricture were excluded.

RESULTS

Of the 461 hits, 62 studies were included in the analysis. Among the wound-protective strategies, polyglycolic acid sheets showed the most convincing evidence with a 37.5% stricture rate and excellent safety. Regenerative medicine, using cell sheets of autologous keratinocytes, resulted in a 25% stricture rate, although with cost and availability concerns. Among anti-proliferative treatment modalities, steroid treatment, either endoscopically injected triamcinolone in the resection wound or orally administered prednisolone, proved effective with an overall stricture rate of 13.5%, with safety concerns regarding late oesophageal perforations and infectious morbidity. Among mechanical treatment options, poorly effective and high-risk preventive balloon dilation tend to be replaced by prophylactic covered stent, with 18-28% stricture rates.

CONCLUSIONS

Although oral or locally injected steroids are promising options, no currently available technique is sufficiently efficient and devoid of significant safety concerns to recommend its routine use for the prevention of strictures after extensive endoscopic resection. Improving our knowledge in the mechanisms of oesophageal wound healing will guide the development of novel methods for stricture prevention.

Imaging in lower urinary tract infections

In epididymo-orchitis, a sonogram shows a non-homogenous and hypertrophied epididymis and testis, with increased vascularisation seen on a Doppler sonogram. Abscesses must be investigated using sonography so that a necrotic tumour is not misdiagnosed. In prostatitis, sonography is indicated to investigate urine retention and where treatment has failed (to look for a blockage, an abscess, or pyelonephritis). Endorectal sonography is the best imaging modality for analysing the parenchyma, but otherwise has limited value. Chronic prostatitis is the main differential diagnosis from prostate cancer; the two may be distinguished using diffusion MRI. In cases of cystitis, imaging is indicated when a patient has recurrent cystitis (to investigate what the causative factors might be), or an infection with a less common bacterium (to look for calcifications, emphysema, any involvement of the upper urinary tract), and in cases of cystitis with pseudotumour.

[pT3N0 prostate cancer treated with radical prostatectomy as sole treatment: Oncological results and predictive factors of recurrence]

OBJECTIVES

To evaluate biological free survival in patients with locally advanced prostate cancer treated with radical prostatectomy (RP) as sole treatment, and to analyse predictive factors of recurrence.

PATIENTS AND METHOD

We retrospectively studied patients treated between 1996 and 2006 for a pT3N0 prostate cancer with RP without any adjuvant treatment. The main endpoint was PSA relapse, defined as two successive elevations of PSA>0.2 ng/mL. An association between PSA free survival and PSA, Gleason score, pathological stage and surgical margins status was statistically assessed.

RESULTS

A total of 147 patients were included. Median preoperative PSA was of 10 ng/mL. Pathological stage was pT3b in 30% of the cases and surgical margins showed cancer involvement in 63% of the cases. Gleason score was ≥3+4 in 74% of the cases. Postoperative PSA was undetectable in 121 (82%) patients. Median follow up following RP was of 5 years. The 5-year-PSA free survival was of 48%. Multivariate analysis showed that preoperative and postoperative PSA, as well as Gleason score were predictors of PSA relapse (P<0.05). In patients with undetectable postoperative PSA, 5-year-PSA free survival was of 56%. Seminal vesicle involvement and Gleason score ≥3+4 were the only independent predictors of PSA relapse.

CONCLUSIONS

After RP for pT3N0 prostate cancer, the only predictive factors of recurrence were postoperative PSA and Gleason score. In case of undetectable postoperative PSA, surveillance seems acceptable if Gleason score is <3+4 and in the absence of seminal vesicle involvement.

Multiparametric MRI is helpful to predict tumor focality, stage, and size in patients diagnosed with unilateral low-risk prostate cancer

To study the staging accuracy of multiparametric magnetic resonance imaging (MRI) in patients showing unilateral low-risk cancer on prostate biopsy. A total of 58 consecutive patients with low-risk cancer (D'Amico classification) and unilateral cancer involvement on prostate biopsies were included prospectively. All patients underwent multiparametric endorectal MRI before radical prostatectomy, including T2-weighted (T2W), diffusion-weighted (DW) and dynamic contrast enhanced (DCE) sequences. Each gland was divided in eight octants. Tumor foci >0.2 cm(3) identified on pathological analysis were matched with MRI findings. Pathological examination showed tumor foci >0.2 cm(3) in 50/58 glands (86%), and bilateral tumor (pathological stagepT2c) in 20/58 (34%). For tumor detection in the peripheral zone (PZ), T2W+DWI+DCE performed significantly better than T2W+DWI and T2W alone (P<0.001). In the transition zone (TZ), only T2W+DWI performed better than T2W alone (P=0.02). With optimal MR combinations, tumor size was correctly estimated in 77% of tumor foci involving more than one octant. Bilateral tumors were detected in 80% (16/20) of cases. In patients with unilateral low-risk prostate cancer on biopsy, multiparametric MRI can help to predict bilateral involvement. Multiparametric MRI may therefore have a prognostic value and help to determine optimal treatment in such patients.

FDG-PET improves surgical outcome in negative MRI Taylor-type focal cortical dysplasias

OBJECTIVE

To determine the diagnostic accuracy and prognostic value of ¹⁸FDG-PET in a recent series of patients operated for intractable partial epilepsy associated with histologically proven Taylor-type focal cortical dysplasia (TTFCD) and negative MRI.

METHODS

Of 23 consecutive patients (12 male, 7-38 years old) with negative 1.5-Tesla MRI, 10 exhibited subtle nonspecific abnormalities (e.g., unusual sulcus depth or gyral pattern) and the 13 others had strictly normal MRI. FDG-PET was analyzed both visually after coregistration on MRI and using SPM5 software. Metabolic data were compared with the epileptogenic zone (EZ) determined by stereo-EEG (SEEG) and surgical outcome.

RESULTS

Visual PET analysis disclosed a focal or regional hypometabolism in 18 cases (78%) corresponding to a single gyrus (n = 9) or a larger cortical region (n = 9). PET/MRI coregistration detected a partially hypometabolic gyrus in 4 additional cases. SPM5 PET analysis (n = 18) was concordant with visual analysis in 13 cases. Location of PET abnormalities was extratemporal in all cases, involving eloquent cortex in 15 (65%). Correlations between SEEG, PET/MRI, and histologic findings (n = 20) demonstrated that single hypometabolic gyri (n = 11) corresponded to EZ and TTFCD, which was localized at the bottom of the sulcus. Larger hypometabolic areas (n = 9) also included the EZ and the dysplastic cortex but were more extensive. Following limited cortical resection (mean follow-up 4 years), seizure freedom without permanent motor deficit was obtained in 20/23 patients (87%).

CONCLUSIONS

¹⁸FDG-PET coregistered with MRI is highly sensitive to detect TTFCD and greatly improves diagnosis and surgical prognosis of patients with negative MRI.

[Diffusion-weighted MR imaging of the prostate]

Functional imaging complements T2-weighted imaging in the evaluation of the prostate. The most frequently used techniques are diffusion-weighted imaging and perfusion imaging following the intravenous administration of contrast material. Perfusion imaging has high sensitivity and moderate specificity, even when using a quantitative technique, because contrast kinetics in some cases of peripheral zone prostatitis and benign transition zone hyperplasia may simulate cancer. Diffusion-weighted imaging is currently under evaluation but appears to be preferable to dynamic perfusion MR imaging because of its higher specificity and simpler acquisition. Functional imaging of the prostate is performed to detect cancers missed on biopsies or evaluate the volume of a newly diagnosed clinically localized cancer to assist in therapy selection. Future applications for image-guidance of targeted therapies to the tumor are currently investigational.

Le syndrome de Rasmussen à début tardif : caractéristiques cliniques et thérapeutiques

Rasmussen's syndrome is a rare inflammatory brain disease characterized by severe intractable epilepsy, and unilateral progressive motor defect associated with controlateral hemispheric atrophy. The disorder usually affects children, although occasional reports of adult-onset Rasmussen's syndrome have been reported. We report her four patients in whom seizures began in adolescence or adulthood with clinical and radiological symptoms suggesting the diagnosis of Rasmussen's syndrome. We compared them with thirty-three cases described in the literature between 1987 and 2004. While adult-onset Rasmussen's syndrome may mimic the early-onset form, symptoms often progress more slowly and the neurological defect is more variable. Occipital lobe involvement appears to be more common than in the childhood form, and some atypical features may be noted such as bilateral hemispheric involvement or a picture of temporal lobe epilepsy or the présence of movement disorders at the beginning of the disease. Surgical hemispheric disconnection that appears the most effective treatment in children to improve seizure control is not indicated in adults for evident functional reasons. Based on recent pathogenic concepts, different medical treatments may be proposed. Large multicentric controlled studies are mandatory to define a clear medical therapeutic strategy in these cases of adult-onset.

[Criteria of diagnosis and grading of oligodendrogliomas or oligo-astrocytomas according to the WHO and Sainte-Anne classifications]

Two main classification systems are used in France for the histological typing and grading of oligodendrogliomas: the WHO and Sainte-Anne Hospital (SA) classifications. According to the WHO, the typing of diffuse gliomas is based on the predominant cell type, oligodendroglial versus astrocytic. In contrast, the SA classification is based on the distinction of two patterns of tumor growth, solid tumor tissue versus isolated tumor cells and also relies on imaging and clinical features. According to this approach, the SA classification includes in the category of oligodendrogliomas, the fibrillary or gemistocytic diffuse astrocytomas (WHO grade II) as well as a substantial proportion of astrocytomas WHO grade III, 2) the WHO uses multiple histological criteria for the grading of oligodendrogliomas (grade II versus grade III), including the degree of differentiation, cellular atypia, mitotic activity and necrosis. In contrast, the SA grading of these tumors (grade A versus B) only uses two criteria: the presence or absence of endothelial hyperplasia, and the presence or absence of contrast enhancement. This last criterion allows overcoming the problems related to the representativeness of surgical samples. Difficulties and discrepancies regarding the diagnosis of oligodendrogliomas are in part due to the lack of immunomarker for the identification of tumoral oligodendrocytes. The potential interest of new markers of oligodendroglial precursors for the diagnosis of these tumors will further be discussed.

[Oligodendrogliomas: historical background of classifications]

The story of the classifications for gliomas is related to the development of the techniques used for cytological and histological examination of brain parenchyma. After a review of these techniques and the progressive discovery of the central nervous system cell types, the main classifications are presented. The first classification is due to Bailey and Cushing in 1926. It was based on histoembryogenetic theory. Then Kernohan introduced, in 1938, the concept of anaplasia. The WHO classification was published in 1979, then revised in 1993 and 2000. It took into account some data from both previous systems and introduced gradually the notion of histological criteria of malignancy. More recently; molecular genetics data and clinical evolution were retained. The Sainte-Anne classification for oligodendrogliomas is based on both histological and imaging data. It includes the notion of spatial histological structure of oligodendrogliomas. Contrast enhancement is closely related to endotheliocapillary hyperplasia. Gliomas classifications are changing and confusions can be made because of lack of reproductibility and misinterpretations of samples.

[Results of the Sainte-Anne - Lyons series of 318 oligodendroglioma in adults]

INTRODUCTION

Incidence of cerebral oligodendrogliomas is increasing because of better recognition made possible by improved classifications. We studied a homogeneous series using the Sainte-Anne grading scale in order to better understanding the history of these tumors with or without treatment and to assess prognosis and associated factors.

PATIENTS AND METHODS

A retrospective series of 318 adult patients with oligodendroglioma (OLG) treated at Hôpital Sainte-Anne, Paris (SA) and Hôpital Neurologique, Lyons (L) between 1984 and 2003 was analyzed: 182 grade A OLG (SA + L), 136 grade B among which a homogenous series of 98 (SA) were included. For grade A: age at diagnosis ranged from 21 to 70 (mean: 41), sex ratio was 1.28. For grade B: age at diagnosis ranged from 12 to 75 (mean: 45.5), sex-ratio was 1.58. The main first symptoms were: epilepsy (A: 91.5%; B: 76%), intracranial hypertension (A: 7.9%; B: 14.6%), neurological deficit (A: 5.1%; B: 17.7%). The most frequent locations were: frontal, insular and central for both A and B. Mean size was 55 mm for grade A, 62 mm for B. Calcifications were found in 20% of A, 48.5% of B. No tumor was enhanced on imaging (CT/MRI) in grade A, all but 7 in grade B. All patients underwent surgery either for biopsy (A: 47.2%; B: 53%), or removal which was partial (A: 26.4% vs B: 19.4%) or extended (A: 36.3% vs B: 37.8%). Fifty-six patients underwent 2 procedures and 12 three procedures. Radiotherapy was performed in 76.9% of grade A, and 91% of B patients, in the immediate postoperative period for 71% A and 82.7% B. Chemotherapy was delivered for 36% of grade A (in the event of transformation to grade B or failure of radiotherapy) and 67.5% of B patients. Among grade A tumors, 38% transformed into grade B within a mean delay of 51 months with a mean follow-up of 78 months.

RESULTS

Median survival was 136 months for grade A and 52 for grade B. Survival at 5, 10 and 15 was 75.5%, 51% and 22.4% for grade A vs 45.2%, 31.3% and 0% for grade B respectively. In univariate and multivariate analysis, grade A survival was associated with age at diagnosis, tumor size, large removal and response to radiotherapy. Grade B survival was associated with age at diagnosis, wide removal and sharply defined limits of the tumor on imaging.

CONCLUSIONS

Analysis of both published data and this series underlines many prognostic parameters. It shows that OLG are heterogeneous tumors even in each grade (A and B). Treatment should consequently progress towards more targeted procedures for patients mainly with postoperative radiotherapy and chemotherapy.

[Cerebral cavernomas, epilepsy and seizures. Natural history and therapeutic strategy]

PURPOSE

To review, from a retrospective series of 48 patients presenting with seizures associated with one or more supratentorial cavernoma(s), the natural history of the seizures and outcome according to medical and surgical treatment.

METHODS

Patients were divided into two groups: group A included patients presenting with a single seizure or rare seizures (n=21), and group B patients having intractable epilepsy (n=27). All received antiepileptic drugs and 35 were operated on (12 in the group A and 23 in the group B). Stereo-EEG was performed in 8 patients in group B. Surgery included lesionectomy alone (n=16), resection of the cavernoma and perilesional tissue (n=7) or tailored corticectomy including the cavernoma (n=12).

RESULTS

The natural history of seizures was different in the two groups: mean age at seizure onset was 25 years in group B and 33 years in group A (p<0.05), seizures were partial in all patients in group B and 8 patients in group A (p<0.05). Seizure frequency and periodicity also varied. Prolonged seizure-free periods were observed. The cavernoma was temporal in 17 patients in group B and 4 patients in group A (p<0.01). In group A, seizure outcome was favorable following surgery or with antiepileptic medication only (7 patients out of 12 operated were seizure-free, as were 5 out of 7 non-operated). In group B, seizure outcome was better after surgery than with medication only (17 patients out of 23 operated were in Engel's Class I, while 3 patients of 4 non-operated patients had persisting seizures despite antiepileptic polytherapy).

CONCLUSION

Variations in seizure severity in patients harboring cavernomas suggest different therapeutic approaches. In case of unique or rare seizures, surgical resection of the cavernoma is appropriate, but benefits of surgery over antiepileptic medication in terms of seizure control remains unclear. Intractable epilepsy associated with cavernomas is better controlled after surgery rather than with medication only. In these patients, a detailed preoperative work-up is necessary and should be followed by wide resection associated or not with corticectomy, especially in the temporal lobe. Evaluation of outcome after surgery should consider the surgical strategy, antiepileptic medications and the patient's seizure history.

Functional endothelin ET B receptors are selectively expressed in human oligodendrogliomas

Endothelin-1 (ET-1), a vasoactive and mitogenic peptide mainly produced by vascular endothelial cells, may be involved in the progression of several human tumors. Here, we present an immunohistochemical analysis of the expression pattern of ET-1 receptor subtypes (ET(A)-R and ET(B)-R) and a functional study of their potential role in human oligodendrogliomas and oligoastrocytomas. By comparison, we assessed the corresponding expression patterns of glioblastomas. Interestingly, a nuclear localization of ET-1 receptor subtypes (associated or not with a cytoplasmic labeling) was constantly observed in tumor cells from all three glioma types. Moreover, we noted a distinct receptor distribution in the different gliomas: a nuclear expression of ET(B)-R by tumor cells was found to be restricted to oligodendrogliomas and oligoastrocytomas, while a nuclear expression of ET(A)-R was only detected in tumor cells from some glioblastomas. Using primary cultures of oligodendroglial tumor cells, we confirmed the selective expression of nuclear ET(B)-R, together with a plasma membrane expression, and further demonstrated that this receptor was functionally coupled to intracellular signaling pathways known to be involved in cell survival and/or proliferation: extracellular signal-regulated kinase and focal adhesion kinase activation, actin cytoskeleton reorganization. In addition, impairment of ET(B)-R activation in these cells by in vitro treatment with an ET(B)-R-specific antagonist induced cell death. These data point to ET-1 as a possible survival factor for oligodendrogliomas via ET(B)-R activation and suggest that ET(B)-R-specific antagonists might constitute a potential therapeutic alternative for oligodendrogliomas.

The expression of PEA-15 (phosphoprotein enriched in astrocytes of 15 kDa) defines subpopulations of astrocytes and neurons throughout the adult mouse brain

Phosphoprotein enriched in astrocytes of 15 kDa (PEA-15) is an abundant phosphoprotein in primary cultures of mouse brain astrocytes. Its capability to interact with members of the apoptotic and mitogen activated protein (MAP) kinase cascades endows PEA-15 with anti-apoptotic and anti-proliferative properties. We analyzed the in vivo cellular sources of PEA-15 in the normal adult mouse brain using a novel polyclonal antibody. Immunohistochemical assays revealed numerous PEA-15-immunoreactive cells throughout the brain of wild-type adult mice while no immunoreactive signal was observed in the brain of PEA-15 -/- mice. Cell morphology and double immunofluorescent staining showed that both astrocytes and neurons could be cellular sources of PEA-15. Closer examination revealed that in a given area only part of the astrocytes expressed the protein. The hippocampus was the most striking example of this heterogeneity, a spatial segregation restricting PEA-15 positive astrocytes to the CA1 and CA3 regions. A PEA-15 immunoreactive signal was also observed in a few cells within the subventricular zone and the rostral migratory stream. In vivo analysis of an eventual PEA-15 regulation in astrocytes was performed using a model of astrogliosis occurring along motor neurons degeneration, the transgenic mouse expressing the mutant G93A human superoxyde-dismutase-1, a model of amyotrophic lateral sclerosis. We observed a marked up-regulation of PEA-15 in reactive astrocytes that had developed throughout the ventral horn of the lumbar spinal cord of the transgenic mice. The heterogeneous cellular expression of the protein and its increased expression in pathological situations, combined with the known properties of PEA-15, suggest that PEA-15 expression is associated with a particular metabolic status of cells challenged with potentially apoptotic and/or proliferative signals.

Stereotactic CT-guided brain biopsy in the dog

This study evaluated the accuracy of a new stereotactic CT-guided brain biopsy (SCTGBB) device on 23 client-owned dogs which presented with a brain lesion. Biopsy of the lesion was achieved in 95 per cent of cases. The target tissue was not sampled in one dog. Complications were observed in six dogs. Two dogs with highly vascularised brainstem tumours died after SCTGBB. Minor complications (slight variation in the neurological status) were observed in a further four cases. A diagnosis was reached in 16 dogs after cytological examination and in 21 dogs after histological evaluation. SCTGBB is an accurate diagnostic method for the diagnosis of brain lesions.

Dysembryoplastic neuroepithelial tumors: CT, MR findings and imaging follow-up: a study of 53 cases

PURPOSE

To evaluate CT and MRI features and long term imaging follow-up of a large series of dysembryoplastic neuroepithelial tumors (DNTS).

PATIENTS AND METHODS

We retrospectively analyzed CT (100%) and MR imaging (83%) findings of 53 patients with complex (n = 14), simple (n = 6) or non specific histological forms (n = 33) of DNTS. All patients underwent epilepsy surgery for the treatment of drug resistant partial seizures. Preoperative radiological follow-up from two to 10 years (81%) and a post-operative follow-up from one to 13 years (92%) were available.

RESULTS

DNTs are intracortical tumors with no mass effect and no peritumoral edema. An associated deformity of the overlying skull was observed in 44% of the 34 patients with a cortical lesion of the convexity. We found a contrast enhancement of the lesion in 21% of cases, a calcic hyperdensity in 36% of cases and a cystic part in 7.5% of cases. DNTs were hypodense (82%) on CT examinations and had a decreased signal on the T1 Weighted Images (95%) and a hypersignal in T2 Weighted Images (100%) on MR imaging. Eighty-one percent of patients had a mean preoperative radiological follow-up of four years and the tumor was stable in size in all cases; 92% of patients had a mean post-operative radiological follow-up of 4.5 years and no recurrence was seen.

CONCLUSION

Three radiological features of DNTs are helpful for the diagnosis: cortical location, absence of mass effect and no surrounding edema. Clinical, radiological and histopathological findings have to be considered together in order to assess the diagnosis and to differentiate DNTs, which are stable lesions from gliomas.

[Parenchymal changes after radiosurgery of cerebral arteriovenous malformations. Clinical and MRI data]

BACKGROUND AND PURPOSE

Purposes of this study are to describe different parenchymal changes seen after radiosurgery of cerebral arteriovenous malformations and the clinical symptoms which can be associated, and risk factors correlated with them.

PATIENTS

and method. From the whole population of 705 patients with a cerebral arteriovenous malformations treated by radiosurgery between 1984 and 1998, clinical from 615 patients and post radiosurgery MRI data from 367 patients were reviewed. Neurological deficit occurred in 5.37% of cases and was still persistant in 1.46% of cases. Delay of occurrence of deficits ranged from 6 to 83 months (mean: 27 months, median: 15 months). Parenchymal changes seen in MRI were classified in 4 grades: 1 without parenchymal changes, 2 hypersignal in sp T2, 3=2 with homogenous enhancement with gadolinium, 4 with hyposignal in spT1 and annular irregular enhancement. Several parameters (size, volume, angioarchitecture of the cerebral arteriovenous malformation, dosimetric parameters) were studied and correlations were searched by uni and multivariate analysis with occurrence and delay of occurrence of deficits or parenchymal changes.

RESULTS

In multivariate analysis, only size was significantly correlated with occurrence of parenchymal changes (p=0.0016); only size of the malformation was significantly correlated with delay of occurrence of parenchymal changes (p=0.0082); only grade 4 was correlated with occurrence of neurological deficit (p<0.00001). However, when only "a priori" parameters (known before radiosurgery) are introducted in logistic model, size taille (p=0.02) and hypoplasy of a sinus (p=0.0049) are significantly correlated with occurrence of neurological deficit. Only parenchymal changes grade 4 was significantly correlated with delay of occurrence of a neurological deficit (p<0.00001). However, when only a priori parameters (known before radiosurgery) are introducted in logistic model, only arterial steal (p=0.054) was significantly correlated with delay of occurrence of a neurological deficit.

CONCLUSION

Parenchymal changes are various in expression, signification and clinical symptoms associated with them. They must be known and recognized for better prevention and symptomatic treatment as well.

[Surgical removal of radio-induced lesions after radiosurgery of cerebral arteriovenous malformations]

Radioinduced lesions after radiosurgery of cerebral arteriovenous malformations may be associated with an increased signal on T2-weighted and gadolinium enhancement on T1-weighted MR images. They do not have necessarily a poor prognosis. These lesions are mostly asymptomatic. But in a few cases they can be associated with severe clinical symptoms which can become corticodependant or corticoresistant. We present the 5 cases of such cerebral arteriovenous malformations treated by radiosurgery, out of our series of 705 patients. The removal was easier than that of untreated cerebral arteriovenous malformations, and led to a complete recovery of symptoms and progressive decrease of imaging abnormalities. Such surgery should be proposed in case of symptomatic radioinduced lesions which fail to respond to steroids.

[The "smears" technique for the extemporaneous examination: diagnostic contribution to neurosurgical pathology]

Smear preparation is a fairly accurate, simple and reliable tool for rapid intraoperative diagnosis of central nervous system tumors. Compared with frozen sections this technique has the advantage of being both more accurate for cytological details and of requiring less tissue. In addition final histological analysis after direct formalin fixation is of better quality than post freezing fixation. This technique is most helpful in the field of neuro-oncological pathology specially in glial tumors and in stereotactic biopsy procedures. The cytological aspects and smear patterns disclose important complementary diagnostic information for the histopathological examination.

Vascular endothelial growth factor expression in oligodendrogliomas: a correlative study with Sainte-Anne malignancy grade, growth fraction and patient survival

Microangiogenesis is a delayed but crucial event in the malignant progression of oligodendrogliomas. Accord-ingly, in the new Sainte-Anne grading system of oligodendrogliomas, endothelial hyperplasia and contrast enhancement, both being indicators of microangiogenesis, are key criteria for the distinction of grade A from grade B tumours. Vascular endothelial growth factor (VEGF) is a potent angiogenic factor: a strong correlation between VEGF expression, Sainte-Anne malignancy grade and patient outcome might thus be expected. In order to assess this hypothesis, VEGF immunostaining was performed in a series of 34 oligodendrogliomas that included 11 grade B and 23 grade A, of which nine became grade B during the study period (mean clinical and imaging follow-up: 41 months). VEGF expression correlated strongly with Sainte-Anne tumour grade (P < 0.001), and inversely with patient survival (P < 0.001) and recurrence-free survival (P = 0.002). One hundred per cent of grade B but only 17% of grade A were VEGF-positive. By contrast, the MIB-1 labelling index did not correlate with VEGF expression, total survival or recurrence-free survival. In accordance with the grading system, this study showed that, in oligodendrogliomas, VEGF expression and microangiogenesis are progression-related phenomena that confer on these tumours a growth advantage by presumably reducing hypoxia-induced apoptotic cell death. These findings might have important implications in the future for the indication and timing of anti-angiogenic therapies.

[High grade (B) oligodendroglioma. Concerns and pitfalls in the intraoperative examination of smears]

According to the Ste Anne hospital classification and grading system of oligodendrogliomas the presence of contrast enhancement on MRI and/or the presence of an histological endothelial hyperplasia are correlated with a pejorative prognosis (high grade or grade B). Surgical tumoral exerese and adjuvant chemo or radiotherapy are indicated. When clinical and radiological aspects are typical the extemporaneous diagnosis of oligodendroglioma on smear is usually easy (1). In case of atypical forms: unusual localization or cytological appearance, especially with a small cell hyperchromatic undifferenciated tumor few diagnostic hypothesismay be considered. Four cerebellar tumors are presented with relevant and differential cytological diagnostic criteria. A comparative study between clinical and radiological aspects of medulloblastoma, primitive lymphoma, undifferenciated small cell lung carcinoma, and grade B oligodendroglioma is presented.

Dysembryoplastic neuroepithelial tumors: nonspecific histological forms -- a study of 40 cases

OBJECTIVE

To demonstrate that DNTs include a large morphological spectrum of tumors that cannot be histologically distinguished from conventional categories of gliomas.

METHODS

All tumors from patients who underwent epilepsy surgery in Sainte-Anne hospital (Paris) that histologically resembled gliomas and did not conform to current histological criteria for DNTs or gangliogliomas were entered in the study.

RESULTS

According to the WHO histological classification, the 40 tumors resembled: pilocytic astrocytomas (4 cases), astrocytomas (16 cases), anaplastic astrocytoma (1 case), oligodendrogliomas (10 cases), oligo-astrocytomas (8 cases) or anaplastic oligo-astrocytomas (1 case). However foci of cortical dysplasia could be observed in 47% of the cases. Clinical presentation and imaging features were strikingly similar to that observed in typical DNTs. Although surgical removal was incomplete in 28% of the cases and none of the patients underwent chemo or radiotherapy, none of the tumors recurred (mean follow-up: 7 years). Moreover, serial preoperative imaging in 26 patients (mean follow-up: 4.5 years) demonstrated that these lesions were perfectly stable.

CONCLUSIONS

Whatever the histological appearance of a glial tumor, the diagnosis of DNT must be considered when all the following criteria are associated: (1) partial seizures, with or without secondary generalization, beginning before the age 20 years, (2) no neurological deficit or stable congenital deficit, (3) cortical topography of the lesion as better demonstrated by MRI and (4) no mass effect on imaging.

Oligodendrogliomas. Part I: Patterns of growth, histological diagnosis, clinical and imaging correlations: a study of 153 cases

The present study has attempted to demonstrate that the morphological spectrum of oligodendrogliomas includes tumors which are traditionally misinterpreted as 'diffuse fibrillary astrocytoma'. We have shown that these tumors are in fact made of isolated neoplastic oligodendrocytes which are entrapped in a fibrillary background composed of axons and fibrillary reactive gliosis. Analysis in a series of 153 'pure' supratentorial oligodendrogliomas composed of 'classical' or pseudo 'diffuse fibrillary oligodendrogliomas' diagnosed by imaging-based serial stereotactic biopsies showed that 2/3 of the tumors were exclusively made of isolated tumor cells (ITCs) (structure type III) and that only 1/3 of them exhibited both ITCs and solid tumor tissue components (structure type II). The tumor tissue destroys the brain parenchyma and contains new formed microblood vessels whereas ITCs do not destroy the parenchyma and are not associated with microangiogenesis. These fundamentally opposite morphological characteristics were reflected by the following findings: 1) contrast enhancement was observed in 64% of structure type II but was never seen in structure type III oligodendrogliomas. 2) a neurological deficit occurred in 57% of structure type II but in only 8% of structure type III oligodendrogliomas. 3) using the new grading system described in the companion paper to this study, we found that the biological behavior of oligodendrogliomas was also closely related to the patterns of tumor growth. From a synthesis of data gathered in this study it is suggested that emergence of microangiogenesis within a tumor which at first grows slowly with a structure type III pattern is a crucial event toward more aggressive behavior.

Oligodendrogliomas. Part II: A new grading system based on morphological and imaging criteria

This second part of our study of 'pure' oligodendrogliomas focuses on survival data analysis. In order to identify potentially useful prognostic factors and to assess the effectiveness of a new grading system, the 79 patients in the previously analyzed series for whom adequate follow-up could be obtained (52%) were entered in the present analysis. Statistical analysis demonstrated that contrast enhancement and endothelial hyperplasia had powerful and similar influence on survival. Median survival with and without contrast enhancement were: 3 versus 11 years, and with or without endothelial hyperplasia were: 3.5 versus 11 years. Conversely, the degree of nuclear atypia and presence or absence of mitosis or necrosis were not correlated with survival. These findings allowed us to devise a simple grading system which discriminates two malignancy grades as follows: absence of endothelial hyperplasia and of contrast enhancement = Grade A, presence of endothelial hyperplasia and/or of contrast enhancement = Grade B. Of the 79 oligodendrogliomas in this study, 59 tumors were categorized as grade A and 20 as grade B. Median survival were: 11 years in grade A and 3.5 years in grade B. Five-year and 8-year survival rates were: 89% and 60% in grade A and: 33% and 15% in grade B. Double blind grading between two independent observers was concordant in 96% of the cases. Application of this simple efficient and reproducible grading scheme should permit reliable comparison of retrospective or prospective therapeutic data emanating from various institutions.

Characterization of stable RNAs from the resected intestinal tissues of individuals with either Crohn's disease or ulcerative colitis

Circular RNAs reminiscent of viroids and the human hepatitis delta virus have been proposed as possible nonconventional pathogens responsible for Crohn's disease and ulcerative colitis, two inflammatory bowel diseases. Consequently, RNA was extracted from various areas of intestinal tissues from individuals with either Crohn's disease or ulcerative colitis as well as several appropriate control diseases, and analyzed by two-dimensional gel electrophoresis. No circular viroid-like RNAs (< 1500 nucleotides) were detected, confirming a previous report that was limited to the investigation of small RNAs (< 300 nucleotides). However, three small, unusually stable, linear RNAs were shown to be associated to both Crohn's disease and ulcerative colitis tissues: a specific 28S ribosomal RNA cleavage product characterized previously; a 5.8S ribosomal RNA conformer; and a fragment homologous to transcripts from DNA CpG islands. The two last RNAs were detected prior to visible morphological tissue alterations, suggesting that they are produced early during the inflammation and that they have value as molecular diagnostic tools for the inflammatory bowel diseases. The potential cellular mechanisms producing these RNAs and their involvement in inflammatory bowel disease are discussed.

Rapid washout of technetium-99m-MIBI from a large parathyroid adenoma

We report a case of rapid 99mTc-methoxyisobutylisonitrile (MIBI) clearance from a parathyroid adenoma. A double-phase 99mTc-MIBI parathyroid scintigraphy was performed on a 62-yr-old female evaluated for primary hyperparathyroidism. A large parathyroid adenoma was visualized caudal to the left lobe of the thyroid gland with an unusually rapid washout of the tracer from tumor tissue. Histologic tissue examination confirmed the presence of a parathyroid adenoma and the absence of oxyphil cells. Care should be taken in interpretation of 99mTc-MIBI parathyroid scintigrams because some adenomas can present a rapid release of the radiotracer in a double-phase study. Technetium-99m-MIBI retention could be related to the number of mitochondria-rich cells in parathyroid adenomas or to hyperplasia.

Anti-colony-stimulating factor-1 antibody staining in primary breast adenocarcinomas correlates with marked inflammatory cell infiltrates and prognosis

BACKGROUND

Clinical studies have shown that a marked lymphoplasmocytic reaction in breast tumors is associated with poor prognosis. Such findings raise the possibility that an inflammatory cell reaction might be a tumor-induced response that tends to promote tumor growth.

PURPOSE

We assessed the expression of colony-stimulating factor-1 (CSF-1) as well as the prevalence of specific tumor-infiltrating lymphocytes and monocytes in breast tumors.

METHODS

Tissue sections were obtained from archival paraffin blocks from 196 breast cancer patients. Seventy-eight percent of the women had been treated by mastectomy and 22% by lumpectomy. Median age of the patients was 54 years, and median follow-up was 7.3 years. Immunohistochemical and in situ hybridization techniques were used to characterize the specimens.

RESULTS

Markedly high numbers of CD45RO-positive T- and L26-positive B-cell infiltrates were found in 13% and 17% of the tissue specimens, respectively. CSF-1 receptor-positive monocytes were detected in 48% and CD68-positive monocytes in 90% of the tumors. In turn, tumors with large fractions of CD68-positive monocytes also showed CSF-1 receptor-positive monocytes (P < .0001). CSF-1 was expressed significantly in 74% of the tumors and the CSF-1 receptor in more than 50% of the tumors. Tumors with high percentages of CSF-1 expressing cells also had marked monocyte infiltrates (P = .035). The presence of marked CD45RO-positive T-cell infiltrates and apparent nuclear staining of CSF-1 in tumor cells were associated with the more frequent occurrence of metastases (P = .02 and P = .04, respectively) and with poor survival (P = .02 and P = .03, respectively).

CONCLUSIONS

Large numbers of CD45RO-positive (activated memory but noncytotoxic) T cells as well as a predominant nuclear staining pattern for CSF-1 are associated with a poor outcome in breast cancer patients.

IMPLICATIONS

Nuclear retention of CSF-1 could reflect CSF-1 turnover and function in tumor cells, but new approaches are needed to establish the significance of these observations. Secreted CSF-1 appears to cause monocyte recruitment and activation, thereby modulating immune functions and potentially the expression of the CD45RO phenotype in T cells.

[CSF-1 (colony stimulating factors 1) and CSF-1 receptor. General review and expression in invasive breast tumors]

CSF-1 (colony stimulating factor-1), initially considered to be a monocyte specific growth and differentiation factor [4], has recently been shown to be produced in human endometrium [16], placenta [7], as well as in numerous solid tumors [19-23, 26, 27]. The CSF-1 receptor (a protein product of c-fms) [24] is a member of the tyrosine kinase receptor family and an autocrine or paracrine mechanism of activation has been suggested. Overactivation of this receptor can lead to a malignant phenotype in various cell systems [20, 21]. We review the biology of CSF-1 and fms expression in normal as well as in malignant tissues with particular reference to a potential role for CSF-1 in breast tumour invasion.