Imaging characterization of an adult H3 K27M-altered diffuse midline glioma of the medulla oblongata with a confounding steroid response

We report an uncommon, infratentorial localization of adult H3 K27M-altered diffuse midline glioma arising in a particularly rare site (medulla oblongata). In addition to this unusual presentation, the lesion exhibited a substantial contrast enhancement and size decrease after dexamethasone, generating diagnostic dilemmas. Histology, molecular details, advanced Magnetic Resonance imaging features and differential diagnoses are here described and discussed, as well as common misconceptions about steroid-sensitive mass lesions, and practical difficulties for clinicians involved in the process of making diagnosis.

A cervical solitary fibrous tumor with intramedullary invasion

Solitary fibrous tumor is a tumor originating from the mesenchymal cells, which occurrence in the central nervous system is extremely rare and was described in few patients as to yet. We report on a 53-years old male patient presenting with right upper limb radicular pain and ipsilateral limbs paresis, who was diagnosed with a cervical spinal lesion which, after surgical resection, resulted to be a solitary fibrous tumor (SFT). We discuss imaging, clinical and histopathological findings to allow considering this tumor early in the differential diagnosis.

Primary sellar melanocytoma: pathological, clinical and treatment review

BACKGROUND

Sellar melanocytomas represent a small subgroup of primary melanocytic tumors. They arise from melanocytes located in the meningeal lining of the sellar floor or in the diaphragma sellae and this location is very uncommon. Usually, sellar melanocytomas are benign and slow-growing tumors with a high likelihood of recurrence.

PURPOSE

To our knowledge, due to the rarity of this condition, there are no guidelines regarding their diagnosis and treatment in the medical literature to date. We have developed a narrative review, analyzing the available studies regarding primary sellar melanocytomas reported in the medical literature. We have found ten papers on this topic and all of them are case reports. In all patients, tumor diagnosis was performed after the occurrence of neurological symptoms, in particular progressive visual loss or endocrinological disorders. The diagnosis is difficult, and it requires several preoperative and postoperative investigations, but histological examination is crucial.

CONCLUSIONS

Transsphenoidal surgery is the first-choice treatment. In case of tumor's recurrence or regrowth, the role of radiation therapy and chemotherapy is not entirely clear.

Primary sellar melanocytoma: report of two cases treated at the same institution and their long-term outcome

Sellar melanocytomas represent a small subgroup of primary melanocytic tumors arising from leptomeningeal melanocytes. They are benign, slow-growing tumors with a high risk of recurrence. We report two cases of sellar melanocytoma treated at the same institute. A 35-year-old woman presented with amenorrhea and an intrasellar mass with suprasellar extension simulating a hemorrhagic pituitary adenoma. The second case is a 51-year-old man with progressive visual loss and a recurrence of primary sellar and suprasellar melanocytoma. The first patient underwent gross total resection and the second patient underwent subtotal resection. Neither of them was treated with postoperative adjuvant therapies. The second patient had tumor regrowth 75 months after surgery; he therefore underwent gamma knife radiosurgery. Both patients are alive and well at the last follow-up (140 and 93 months, respectively).

Gene expression profiling in human corticotroph tumours reveals distinct, neuroendocrine profiles

Adrenocorticotrophic hormone (ACTH)-secreting pituitary adenomas give rise to a severe endocrinological disorder, comprising Cushing's disease, with multifaceted clinical presentation and treatment outcomes. Experimental studies suggest that the disease variability is inherent to the pituitary tumour, thus indicating the need for further studies into tumour biology. The present study evaluated transcriptome expression pattern in a large series of ACTH-secreting pituitary adenoma specimens in order to identify molecular signatures of these tumours. Gene expression profiling of formalin-fixed, paraffin-embedded specimens from 40 human ACTH-secreting pituitary adenomas revealed the significant expression of genes involved in protein biosynthesis and ribosomal function, in keeping with the neuroendocrine cell profile. Unsupervised cluster analysis identified 3 distinct gene profile clusters and several genes were uniquely overexpressed in a given cluster, accounting for different molecular signatures. Of note, gene expression profiles were associated with clinical features, such as the age and size of the tumour. Altogether, the findings of the present study show that corticotroph tumours are characterised by a neuroendocrine gene expression profile and present subgroup-specific molecular features.

Long-term outcomes after cosmetic customized prostheses and dermis fat graft in congenital anophthalmia: a retrospective multicentre study

PURPOSE

To evaluate long-term outcomes of progressively enlarging cosmetic customized prostheses (CCP) early after birth followed by dermis fat graft (DFG), as a strategy of socket rehabilitation in children with clinical congenital anophthalmia (CCA).

METHODS

Twenty patients with unilateral and two patients with bilateral CCA were enrolled. All patients were treated by inserting a CCP at the time of their first assessment which was then enlarged. Subsequently they underwent DFG. Differences in vertical palpebral aperture (VPA) and horizontal palpebral length (HPL), between affected and unaffected sides, were recorded at the first CCP fitting as well as before and after DFG. Satisfaction with cosmetic results, prosthetic retention, and complications rate were assessed. Magnetic resonance imaging of the orbit was performed in all patients before and after surgery.

RESULTS

A significant decrease in the difference between the normal and the anophthalmic side of both PA and HPL was found over follow-up. Both VPA and HPL differences decreased by 47.6% (10.5 mm, range 1-28 mm) and by 7.1% (5.8 mm, range 0-18 mm), respectively. Satisfaction in terms of cosmetic outcomes proved to be very positive, being "very satisfied" for families and "satisfied" for physicians. Excellent retention of prostheses was observed in all cases.

CONCLUSIONS

A rehabilitating strategy combining early CCP and further DFG proved to be a valuable approach in children with CCA, offering significant benefits in terms of socket expansion, prosthetic retention, psychological impact, and cosmetic outcomes.

Palate perforation differentiates cocaine-induced midline destructive lesions from granulomatosis with polyangiitis

Cocaine abuse occasionally causes extensive destruction of the osteocartilaginous structures of the nose, sinuses and palate, which mimics the clinical picture of other diseases associated with necrotising midfacial lesions. The differentiation of cocaine-induced midline destructive lesions (CIMDL) and limited granulomatosis with polyangiitis (GPA) may be difficult, particularly if patients do not readily admit substance abuse. We studied 10 patients with CIMDL and palate perforation referred to our Unit between 2002 and 2015. All cases underwent nasal endoscopy, sinus CT or MRI and ANCA test. In 8 patients, a nasal biopsy was performed. The PubMed database was searched to review all cases of palate perforation described in patients affected by CIMDL or GPA. All 10 cases presented with septal perforation and inferior turbinate destruction. We found hard palate perforation in 7 patients, soft palate perforation in 2 patients, and perforation of both in one patient. ANCA testing was negative in 8 patients and positive in 2, with C-ANCA and P-ANCA specificity, respectively. A review of the English literature identified palate perforation in 5 patients with GPA and in 73 patients with CIMDL. The presence of palate perforation in patients with MDL may represent a clinical marker that strongly favors CIMDL over GPA.

Irradiation Fields and Doses in Glioblastoma Multiforme: Are Current Standards Adequate?

Aims and background

The optimum conventional radiotherapy in glioblastoma multiforme patients has not been clearly defined by prospective trials. To better characterize a standard radiotherapy in glioblastoma multiforme, the impact on survival of different fields and doses was analyzed in a retrospective single center series.

Methods

One hundred and forty-seven patients with glioblastoma multiforme, submitted to biopsy only (n = 15), subtotal (n = 48) or total resection (n = 82) and who completed the planned postsurgical radiotherapy, were considered. The median age was 57 years, the male/female ratio 1.5/1, and the performance status ≥70 in 76%. Whole brain irradiation, followed by a boost to partial brain, was used in 75 cases with a whole brain dose of 44–50 Gy (median, 46) and a partial brain dose of 56–70 Gy (median, 60 Gy). Partial brain irradiation alone was used in 72 patients with a dose of 56–70 Gy (median, 61 Gy). Ninety-eight patients received 56–60 Gy (median, 59 Gy) to partial brain whereas 49 patients received 61–70 Gy (median, 63 Gy).

Results

There was an almost significantly longer survival in patients irradiated to the partial brain alone with respect to those also receiving whole brain radiotherapy (P = 0.056). Doses <60 Gy significantly prolonged survival (P = 0.006). Multivariate analysis confirmed that the impact on survival of radiation dose was independent of age, performance status, extent of surgery, field of irradiation and the use of chemotherapy. The extent of irradiation field was not independently related to improved survival.

Conclusions

Our retrospective findings suggest that we reflect on the adequacy of the current standard irradiation parameters. Well-designed prospective trials are necessary to standardize the radiotherapy control group in patients with glioblastoma multiforme to be compared in phase III trials with innovative therapeutic approaches.

Pediatric cerebellar pilocytic astrocytoma presenting with spontaneous intratumoral hemorrhage

Pilocytic astrocytomas (PAs) are benign glial tumors and one of the most common childhood posterior fossa tumors. Spontaneous intratumoral hemorrhage in PAs occurs occasionally, in about 8-20% of cases. Cerebellar hemorrhages in pediatric population are rare and mainly due to head injuries, rupture of vascular malformations, infections, or hematological diseases. We have investigated the still controversial and unclear pathophysiology underlying intratumoral hemorrhage in PAs. Bleeding in low-grade tumors might be related to structural abnormalities and specific angio-architecture of tumor vessels, such as degenerative mural hyalinization, "glomeruloid" endothelial proliferation, presence of encased micro-aneurysms, and glioma-induced neoangiogenesis. The acute hemorrhagic presentation of cerebellar PA in childhood although extremely uncommon is of critical clinical importance and necessitates promptly treatment. We described a case of hemorrhagic cerebellar PA in a 9-year-old child and reviewed the English-language literature that reported spontaneous hemorrhagic histologically proven cerebellar PA in pediatric patients (0-18 years). According to our analysis, the mortality was not related to symptom onset, tumor location, hemorrhage distribution, presence of acute hydrocephalous, and timing of surgery, while the GCS at hospital admission resulted to be the only statistically significant prognostic factor affecting survival outcome. The abrupt onset of signs and symptoms of acute hydrocephalous and consequent raised intracranial pressure are life-threatening conditions, which need emergent medical and neurosurgical treatments. At a later time, the identification of posterior fossa hemorrhage etiology is crucial to select the appropriate treatment and address the surgical strategy, optimizing the postoperative results.

The GIP/GIPR axis is functionally linked to GH-secretion increase in a significant proportion of gsp- somatotropinomas

OBJECTIVE

Glucose-dependent insulinotropic polypeptide receptor (GIPR) overexpression has been recently described in a proportion of gsp^- somatotropinomas and suggested to be associated with the paradoxical increase of GH (GH-PI) during an oral glucose load.

DESIGN AND METHODS

This study was aimed at linking the GIP/GIPR pathway to GH secretion in 25 somatotropinomas-derived primary cultures and correlating molecular with clinical features in acromegalic patients. Given the impairment of the GIP/GIPR axis in acromegaly, an additional aim was to assess the effect of GH/IGF-1 stimulation on GIP expression in the enteroendocrine cell line STC-1.

RESULTS

Nearly 80% of GIPR-expressing somatotropinomas, all of them negative for gsp mutations, show increased GH secretion upon GIP stimulation, higher sensitivity to Forskolin but not to somatostatin analogs. Besides increased frequency of GH-PI, GIPR overexpression does not appear to affect acromegalic patients' clinical features. In STC-1 cells transfected with GIP promoter-driven luciferase vector, IGF-1 but not GH induced dose-dependent increase in luciferase activity.

CONCLUSIONS

We demonstrate that GIPR mediates the GH-PI in a significant proportion of gsp^- acromegalic patients. In these cases, the stimulatory effect of IGF-1 on GIP promoter support the hypothesis of a functional GH/IGF-1/GIP axis. Further studies based on larger cohorts and the development of a stable transgenic model with inducible GIPR overexpression targeted to pituitary somatotroph lineage will be mandatory to establish the real role of GIPR in the pathogenesis of somatotropinomas.

Suprasellar granular cell tumor of the neurohypophysis: surgical outcome of a very rare tumor

PURPOSE

Granular cell tumors of the neurohypophysis are rare, solitary lesions, mostly presenting in the adult age. They rarely grow to a sufficient size to cause mass effect related symptoms and they may be found in most cases incidentally at autopsy. Because of their rarity as of now they have been described only as case reports or included in small clinical series.

METHODS

We report a series of 11 patients, who underwent surgery for granular cell tumors of the neurohypophysis between 1996 and 2013 in a single center.

RESULTS

Mean follow-up time after treatment was 92.2 months (range 9-231 months). Mean age at surgery was 40.7 years (range 12-66 years). There were 7 males (63.6 %) and 4 females (36.4 %). Main symptoms at presentation were: hyperprolactinemia (72.7 %), visual impairment (45.5 %) and headache (36 %). Except for 2 patients, all the others underwent surgery as primary treatment at our Institution, through a transsphenoidal (54.5 %) or a transcranial approach (45.5 %). Overall- and progression-free survival times for the entire series (calculated from the time of diagnosis) were 112.9 and 100.5 months respectively. There was one case of perioperative death in a patient who had undergone repeat transcranial surgery for residual tumor.

CONCLUSIONS

Although extremely rare, granular cell tumors of the neurohypophysis have to be considered in the differential diagnosis of suprasellar masses, to avoid misleading interpretation and consequent wrong therapeutic management. Early diagnosis, extensive tumor removal, opportune indication of adjuvant radiotherapy are the keys to manage these cases.

Dynamic contrast-enhanced and dynamic susceptibility contrast perfusion MR imaging for glioma grading: Preliminary comparison of vessel compartment and permeability parameters using hotspot and histogram analysis

INTRODUCTION

Dynamic susceptibility contrast (DSC)-MRI is a perfusion technique with high diagnostic accuracy for glioma grading, despite limitations due to inherent susceptibility effects. Dynamic contrast-enhanced (DCE)-MRI has been proposed as an alternative technique able to overcome the DSC-MRI shortcomings. This pilot study aimed at comparing the diagnostic accuracy of DSC and DCE-MRI for glioma grading by evaluating two estimates of blood volume, the DCE-derived plasma volume (Vp) and the DSC-derived relative cerebral blood volume (rCBV), and a measure of vessel permeability, the DCE-derived volume transfer constant K(trans).

METHODS

Twenty-six newly diagnosed glioma patients underwent 3T-MR DCE and DSC imaging. Parametric maps of CBV, Vp and K(trans) were calculated and the region of highest value (hotspot) was measured on each map. Histograms of rCBV, Vp and K(trans) values were calculated for the tumor volume. Statistical differences according to WHO grade were assessed. The diagnostic accuracy for tumor grading of the two techniques was determined by ROC analysis.

RESULTS

rCBV, Vp and K(trans) measures differed significantly between high and low-grade gliomas. Hotspot analysis showed the highest correlation with grading. K(trans) hotspots co-localized with Vp hotspots only in 56% of enhancing gliomas. For differentiating high from low-grade gliomas the AUC was 0.987 for rCBVmax, and 1.000 for Vpmax and K(trans)max. Combination of DCE-derived Vp and K(trans) parameters improved the diagnostic performance of the histogram method.

CONCLUSION

This initial experience of DCE-derived Vp evaluation shows that this parameter is as accurate as the well-established DSC-derived rCBV for glioma grading. DCE-derived K(trans) is equally useful for grading, providing different informations with respect to Vp.

A novel composite type I collagen scaffold with micropatterned porosity regulates the entrance of phagocytes in a severe model of spinal cord injury

Traumatic spinal cord injury (SCI) is a damage to the spinal cord that results in loss or impaired motor and/or sensory function. SCI is a sudden and unexpected event characterized by high morbidity and mortality rate during both acute and chronic stages, and it can be devastating in human, social and economical terms. Despite significant progresses in the clinical management of SCI, there remain no effective treatments to improve neurological outcomes. Among experimental strategies, bioengineered scaffolds have the potential to support and guide injured axons contributing to neural repair. The major aim of this study was to investigate a novel composite type I collagen scaffold with micropatterned porosity in a rodent model of severe spinal cord injury. After segment resection of the thoracic spinal cord we implanted the scaffold in female Sprague-Dawley rats. Controls were injured without receiving implantation. Behavioral analysis of the locomotor performance was monitored up to 55 days postinjury. Two months after injury histopathological analysis were performed to evaluate the extent of scar and demyelination, the presence of connective tissue and axonal regrowth through the scaffold and to evaluate inflammatory cell infiltration at the injured site. We provided evidence that the new collagen scaffold was well integrated with the host tissue, slightly ameliorated locomotor function, and limited the robust recruitment of the inflammatory cells at the injury site during both the acute and chronic stage in spinal cord injured rats. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1040-1053, 2017.

Polycomb dysregulation in gliomagenesis targets a Zfp423-dependent differentiation network

Malignant gliomas constitute one of the most significant areas of unmet medical need, owing to the invariable failure of surgical eradication and their marked molecular heterogeneity. Accumulating evidence has revealed a critical contribution by the Polycomb axis of epigenetic repression. However, a coherent understanding of the regulatory networks affected by Polycomb during gliomagenesis is still lacking. Here we integrate transcriptomic and epigenomic analyses to define Polycomb-dependent networks that promote gliomagenesis, validating them both in two independent mouse models and in a large cohort of human samples. We find that Polycomb dysregulation in gliomagenesis affects transcriptional networks associated with invasiveness and de-differentiation. The dissection of these networks uncovers Zfp423 as a critical Polycomb-dependent transcription factor whose silencing negatively impacts survival. The anti-gliomagenic activity of Zfp423 requires interaction with the SMAD proteins within the BMP signalling pathway, pointing to a novel synergic circuit through which Polycomb inhibits BMP signalling.

Intracranial Melanotic Schwannomas

STUDY AIMS

Melanotic schwannomas (MSs) are an extremely rare variant of nerve sheath tumor. Lesions are characterized by melanin-producing cells that resemble ultrastructural features of Schwann cells. The main location is the paraspinal thoracic region, followed by other extraneural locations such as skin, soft tissues, bone, and viscera. Craniofacial and intracranial lesions are extremely rare. They may occur either sporadically or related to familiar syndromes, such as neurofibromatosis type II and Carney complex, a rare multisystemic autosomal dominant hereditary syndrome. Despite the benign histologic appearance, these tumors can recur or metastasize, even after a long time. We provide an overview of the epidemiological, clinical, radiologic, and histopathologic characteristics of intracranial MSs, with particular emphasis on diagnostic and therapeutic strategies and related clinical outcomes.

MATERIAL AND METHODS

We performed a literature review on MSs (1932-2012) regarding intracranial and other localization. An illustrative case is reported.

RESULTS

To the best of our knowledge, 17 papers reporting 18 cases of intracranial MSs were previously published. All these studies are either case report or clinical series describing intracranial MSs. Therapeutic results and prognostic factors were reviewed.

CONCLUSION

Radical surgical resection is considered the treatment of choice for MS, but treatment guidelines still do not exist. Radiotherapy seems to play an important role in reducing the risk of recurrence in the case of subtotal tumor resection. Despite the reported encouraging results, only anecdotal data are available in the pertinent literature. Future studies should focus on the role of radiotherapy as adjuvant treatment when radical surgical excision cannot be achieved.

Metallothioneins as dynamic markers for brain disease in lysosomal disorders

OBJECTIVE

To facilitate development of novel disease-modifying therapies for lysosomal storage disorder (LSDs) characterized by nervous system involvement such as metachromatic leukodystrophy (MLD), molecular markers for monitoring disease progression and therapeutic response are needed. To this end, we sought to identify blood transcripts associated with the progression of MLD.

METHODS

Genome-wide expression analysis was performed in primary T lymphocytes of 24 patients with MLD compared to 24 age- and sex-matched healthy controls. Genes associated with MLD were identified, confirmed on a quantitative polymerase chain reaction platform, and replicated in an independent patient cohort. mRNA and protein expression of the prioritized gene family of metallothioneins was evaluated in postmortem patient brains and in mouse models representing 6 other LSDs. Metallothionein expression during disease progression and in response to specific treatment was evaluated in 1 of the tested LSD mouse models. Finally, a set of in vitro studies was planned to dissect the biological functions exerted by this class of molecules.

RESULTS

Metallothionein genes were significantly overexpressed in T lymphocytes and brain of patients with MLD and generally marked nervous tissue damage in the LSDs here evaluated. Overexpression of metallothioneins correlated with measures of disease progression in mice and patients, whereas their levels decreased in mice upon therapeutic treatment. In vitro studies indicated that metallothionein expression is regulated in response to oxidative stress and inflammation, which are biochemical hallmarks of lysosomal storage diseases.

INTERPRETATION

Metallothioneins are potential markers of neurologic disease processes and treatment response in LSDs.

Solitary clival plasmocytomas: Misleading clinical and radiological features of a rare pathology with a specific biological behaviour

BACKGROUND

Tumours of the clivus are exceptionally rare, representing a diagnostic and a therapeutic challenge. Clival solitary plasmocytomas have been described only as single case reports or included in small clinical series with other intracranial location.

METHODS

Authors report clinical, radiological, and survival data of four patients, who underwent surgery for clival plasmocytomas between 1989 and 2012 in a single centre. Current knowledge about solitary plasmocytomas of the clivus are reviewed.

RESULTS

Follow-up time was 54 months (range: 9-165). Mean age of patient was 57 years, no gender predilection was observed. Main symptoms were headache (75 %) and double vision (75 %), due to third or sixth cranial nerve palsy. Mean time to diagnosis was 8.2 months. All patients underwent surgery as primary treatment, through either a transsphenoidal (75 %) or a transmaxillary approach (25 %). In all cases adjuvant conventional radiotherapy was performed with a median delivered dose of 45 Gy. Only one case of progression into multiple myeloma was observed 13 months after surgery, and the patient died 9 months later. No other recurrences or progression were observed. Mean overall survival and progression free survival time were, respectively, 54 and 51.7 months.

CONCLUSIONS

Although extremely rare, clival plasmocytomas have to be considered in the differential diagnosis of a solitary clival lesion. Biological and clinical features of these tumours strongly differ from those of similar lesions in other part of the body. Early diagnosis, extensive tumour removal, opportune indication of adjuvant treatment with radiotherapy and chemotherapy are the keys to manage these cases.

Primary lymphoma of the central nervous system--a diagnostic challenge

Primary lymphoma of the central nervous system is a distinct diffuse large B-cell lymphoma confined to the nervous system. Whereas classical cases can be classified easily, differential diagnosis can be a challenge in particular in patients who had received treatment prior to biopsy. In the differential diagnosis, other tumours and inflammatory diseases of autoimmune and infectious aetiology need to be considered.

Review of cerebellopontine angle medulloblastoma

Cerebellopontine angle (CPA) medulloblastomas (MB) are rare lesions with few cases previously described in the literature. We report two further cases of CPA MB. The patients were a 22-year-old man and a 26-year-old woman with a mass developing in the CPA. The preoperative radiological diagnosis was vestibular schwannoma in the first case and petrosal meningioma in the second case. The patients were operated on through a retrosigmoid approach. The intraoperative findings revealed an intra-axial tumour and the histological diagnosis was classic type of MB in both cases. We review the literature and discuss pathological and radiological features and possible pathogenesis of CPA MB, underlining the necessity to consider MB in the differential diagnosis of CPA lesions.

The glucose-dependent insulinotropic polypeptide receptor is overexpressed amongst GNAS1 mutation-negative somatotropinomas and drives growth hormone (GH)-promoter activity in GH3 cells

Somatic mutations in the GNAS1 gene, encoding the α-subunit of the heterotrimeric stimulatory G protein (Gαs), occur in approximately 40% of growth hormone (GH)-secreting pituitary tumours. By altering the adenylate cyclase-cAMP-protein kinase A pathway, they unequivocally give somatotroph cells a growth advantage. Hence, the pathogenesis of somatotropinomas could be linked to anomalies in receptors coupled to the cAMP second-messenger cascade. Among them, the glucose-dependent insulinotropic polypeptide receptor (GIPR) is already known to play a primary role in the impaired cAMP-dependent cortisol secretion in patients affected by food-dependent Cushing's syndrome. In the present study, 43 somatotropinomas and 12 normal pituitary glands were investigated for GIPR expression by quantitative reverse transcriptase-polymerase chain reaction, western blotting and immunohistochemistry. Tumoural specimens were also evaluated for GNAS1 mutational status. The effect of GIPR overexpression on cAMP levels and GH transcription was evaluated in an in vitro model of somatotropinomas, the GH-secreting pituitary cell line GH3. GIPR was expressed at higher levels compared to normal pituitaries in 13 GNAS1 mutation-negative somatotropinomas. GIP stimulated adenylyl cyclase and GH-promoter activity in GIPR-transfected GH3 cells, confirming a correct coupling of GIPR to Gαs. In a proportion of acromegalic patients, GIPR overexpression appeared to be associated with a paradoxical increase in GH after an oral glucose tolerance test. Whether GIPR overexpression in acromegalic patients may be associated with this paradoxical response or more generally involved in the pathogenesis of acromegaly, as suggested by the mutually exclusive high GIPR levels and GNAS1 mutations, remains an open question.

Abstract 324: Classic and molecular cytogenetic characterization of adult malignant gliomas

Over the past years there has been an increasing use of molecular markers in the evaluation of adult malignant gliomas, as chromosome 1p/19q codeletion, O-6 methylguanine-DNA methyltransferase (MGMT) gene promoter methylation, and epidermal growth factor receptor (EGFR) gene amplification. However treatment challenges posed by malignant gliomas remain considerable, many of those deriving from their complex and still unclear molecular heterogeneity.

In order to shed further light into genetic aberrations characterizing human malignant gliomas we performed classical and molecular cytogenetic analysis on 35 CNS tumors (21 glioblastoma, 6 astrocitoma, 4 oligodendroglioma, 2 mixed neuroglial tumors, 1 oligoastrocitoma, 1 gliosarcoma). Metaphases were obtained in 25 cases for which conventional karyotyping was carried on by Q-banding: 22 cases showed complex karyotypes, with both numerical and structural chromosomal abnormalities. For 5 cases, M-FISH analysis was performed allowing better definition of such aberrations. EGFR gene copy number was studied by FISH in 27 cases and 5 of them (18,5%) showed EGFR amplification. MGMT gene promoter methylation was analysed by MS-PCR in 17 gliomas and methylation was observed in 9 cases (53%).

1p/19q FISH analysis showed codeletion in 1 oligodendroglioma, 1p deletion in 1 oligodendroglioma and 1 glioblastoma and 19q deletion in 1 astrocitoma and 1 glioblastoma.

In oligodendrogliomas 1p/19q codeletion is caused by the unbalanced translocation t(1;19)(q10;p10) and 1p/19q loss has been validated as both prognostic marker and predictive of radio-chemosensitivity. It is important to distinguish 1p/19q codeletion from 1p partial distal deletions, typically involving 1p36 region. Indeed, 1p36 partial deletions occur in astrocytic tumors and are associated with a poor prognosis; in fact they have not yet been extensively investigated, and no specific gene mapping to this deleted region has been identified so far.

We identified two balanced translocations [t(1;7)(p36;q22); t(1;15)(p36;p21)] in 2 different astrocitomas and 1p36 deletion and 1p36 inversion [inv(1)(p36.2;q42)] in the same glioblastoma. Interestingly, these translocations may represent the first of the two events needed to inactivate a tumor suppressor gene; a second event, such as 1p36 deletion, could lead to the astrocitoma progression to glioblastoma. In particular the glioblastoma carrying both 1p36 deletion and inversion may represent the index case for searching the gene targeted by these alterations. Remarkably, as several chromosome 1p studies in gliomas have been conducted on archival materials by FISH, the real involvement of 1p36 in specific aberrations, such as translocations, may have been underestimated. Further investigation is needed to better characterize 1p36 aberrations in gliomas, and to identify genes involved in these aberrations and potentially related to disease progression.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 324. doi:10.1158/1538-7445.AM2011-324

Salvage therapy with temozolomide in patients with aggressive or metastatic pituitary adenomas: experience in six cases

OBJECTIVE

The prognosis of either pituitary carcinoma or aggressive pituitary adenoma resistant to standard therapies is poor. We assessed the efficacy of treatment with temozolomide, an oral second-generation alkylating agent, in a consecutive series of six patients with aggressive pituitary adenomas.

DESIGN

This was a 1-year prospective study of temozolomide therapy in six consecutive patients with pituitary carcinoma (one case) or atypical pituitary adenoma (five cases) resistant to standard therapies. There were three males and three females. Age at enrollment ranged between 52 and 64 years. Temozolomide was given orally at a dose of 150-200 mg/m(2) per day for 5 days every 4 weeks for a maximum of 12 cycles.

METHODS

Response assessment was based on measurable change in tumor size, as assessed on magnetic resonance imaging, and hormone levels. Response was defined as reduction of at least 50% of tumor size and hormone levels.

RESULTS

Four patients completed the 12 cycles of temozolomide treatment, as planned. Two patients stopped the drug after 3 and 6 months respectively because of the progression of disease. Two patients responded to temozolomide, while the remaining two patients had stable disease. Immunohistochemistry for O(6)-methylguanine-DNA methyltransferase (MGMT) in tumor sample showed a partial association with treatment response.

CONCLUSIONS

Temozolomide treatment has a wide range of efficacy in patients with pituitary carcinoma or locally aggressive pituitary adenoma. Positive staining for MGMT seems likely to predict a lower chance of response.

Early results of surgery in patients with nonfunctioning pituitary adenoma and analysis of the risk of tumor recurrence

OBJECT

Nonfunctioning pituitary adenomas (NFPAs) are benign tumors of the pituitary gland that typically cause visual and/or hormonal dysfunction. Surgery is the treatment of choice, but patients remain at risk for tumor recurrence for several years afterwards. The authors evaluate the early results of surgery and the long-term risk of tumor recurrence in patients with NFPAs.

METHODS

Between 1990 and 2005, 491 previously untreated patients with NFPA underwent surgery at the Università Vita-Salute. Determinations of recurrence or growth of the residual tumor tissue during the follow-up period were based on neuroradiological criteria.

RESULTS

Residual tumor after surgery was detected in 173 patients (36.4%). Multivariate analysis showed that invasion of the cavernous sinus, maximum tumor diameter, and absence of tumor apoplexy were associated with an unfavorable surgical outcome. At least 2 sets of follow-up neuroimaging studies were obtained in 436 patients (median follow-up 53 months). Tumors recurred in 83 patients (19.0%). When tumor removal appeared complete, younger age at surgery was associated with a risk of tumor recurrence. In patients with incomplete tumor removal, adjunctive postoperative radiotherapy had a marked protective effect against growth of residual tumor.

CONCLUSIONS

Complete surgical removal of NFPAs can be safely achieved in > 50% of cases. Visual symptoms and, less frequently, pituitary function may improve after surgery. However, tumor can recur in patients after apparently complete surgical removal. In patients with incomplete tumor removal, radiation therapy is the most effective adjuvant therapy for preventing residual tumor growth.

Evolution of a prolactin-secreting pituitary microadenoma into a fatal carcinoma: a case report

Pituitary carcinomas are very rare tumors, nearly always presenting as widely invasive masses, although the hallmark of these lesions is the finding of distant metastases. One third of reported cases are prolactin (PRL)-secreting tumors. We report the case of a fatal pituitary carcinoma evolving within 4 years from a PRL-secreting microadenoma. A 22-year-old woman presented because of galactorrhea. Evaluation of the patient disclosed slight hyperprolactinemia and magnetic resonance imaging (MRI) showed a 7-mm intrapituitary lesion, which responded to treatment with cabergoline. About 4 years after the first evaluation she developed sudden headache, ptosis, and diplopia in the right eye. MRI disclosed the growth of a large pituitary mass, invading the right cavernous sinus. Despite two trans-sphenoidal surgical procedures followed by gamma-knife radiosurgery, the patient showed rapid local progression of the tumor and the occurrence of new lung lesions, probably of metastatic nature. The patient died 7 months after the development of her first neurological symptoms because of tumor apoplexy and subsequent subarachnoid hemorrhage. This case represents the first documented rapid evolution from a microprolactinoma initially responding to dopamine agonists to a fatal pituitary carcinoma.

Expression study of the target receptor tyrosine kinase of Imatinib mesylate in skull base chordomas

Chordomas are rare neoplasms arising along the axial skeleton. Up to now, the most suitable therapeutic approach is based on a combination of surgical excision and radiotherapy. Chemotherapy in not applied due to its reported low efficacy. Recently, evidence on the efficacy of Imatinib mesylate in two patients has been reported. We analyzed 14 chordoma samples for the expression of the Imatinib mesylate targets by means of RT-PCR and immunohistochemistry and found that PDGFR alpha and PDGFR beta are in some cases expressed in neoplastic cells, while the stromal counterpart of the same tumor shows the above receptors. Findings on the PDGFA/PDGFB expression suggest a receptor-activated status. Our study provides new insights into the specific localization of Imatinib mesylate targets in skull base chordomas that could be taken into account for the setting up of a pharmacological treatment for this tumor.

Reactive perivascular T-cell infiltrate predicts survival in primary central nervous system B-cell lymphomas

Well-established histopathological prognostic factors are lacking in primary central nervous system (CNS) lymphomas (PCNSL). The present study investigated the presence and prognostic role of tumour necrosis (TN) and reactive perivascular T-cell infiltrate (RPVI), defined as a rim of small reactive T-lymphocytes occurring alone or located between the vascular wall and large neoplastic cells, in tumour samples from 100 immunocompetent patients with PCNSL. World Health Organization histotypes of the patients were: 96 diffuse large B-cell lymphomas, two Burkitt-like lymphomas, one anaplastic large T-cell lymphoma and one unclassified B-cell lymphoma. TN was observed in 24 (24%) cases and RPVI in 26 (36%) of 73 assessable cases. Patients with RPVI-positive lesions exhibited a significantly better overall survival (OS) than patients with RPVI-negative lymphoma, particularly among patients treated with high-dose methotrexate-based chemotherapy (3-year OS: 59 +/- 14% vs. 42 +/- 9%, P = 0.02). By contrast, the presence of TN did not demonstrate prognostic significance. Multivariate analysis confirmed an independent association between RPVI and survival. In conclusion, the presence of RPVI is independently associated with survival in PCNSL. This parameter can be easily and routinely assessed at diagnosis on histopathological specimens.

Intrasellar paraganglioma: a case report and review of the literature

Intrasellar paragangliomas are very rare lesions with only six previous cases described in the literature. We present a further case of intrasellar paraganglioma. The patient was a 52 yr-old man who developed two transient ischemic attacks. A CT scan showed an intra- and supra-sellar expanding lesion, which was regarded as a possible non-functioning pituitary macro-adenoma. Removal of the lesion was accomplished by transsphenoidal surgery. Histological examination was diagnostic of a paraganglioma. We review the literature and discuss pathological features and possible pathogenesis of sellar and parasellar paragangliomas, underlining the necessity to consider paraganglioma in the differential diagnosis of sellar lesions.

Neuromelanin and iron in human locus coeruleus and substantia nigra during aging: consequences for neuronal vulnerability

In this study a comparative analysis of iron molecules during aging was performed in locus coeruleus (LC) and substantia nigra (SN), known targets of Parkinson's Disease (PD) and related disorders. LC and SN neurons, especially the SN pars compacta, degenerate in PD and other forms of parkinsonism. Iron and its major molecular forms, such as ferritin and neuromelanin (NM), were measured in LC and SN of normal subjects at various ages. Iron levels were lower, H-ferritin/iron ratio was higher and the iron content in NM was lower in LC than in SN. Iron deposits were abundant in SN tissue, very scarse in LC tissue and completely absent in pigmented neurons of both SN and LC. In both regions H- and L-ferritins were present only in glia. This suggests that in LC neurons iron mobilization and toxicity is lower than that in SN and is efficiently buffered by NM. Ferritins accomplish the same buffering function in glial cells.

Correlation between clinical characteristics and proliferative activity in patients with craniopharyngioma

OBJECTIVES

The aim of the study was to correlate the Ki-67 and cyclin A labelling index (LI) with clinical characteristics and risk of recurrence of craniopharyngiomas.

METHODS

47 consecutive patients were studied, 21 female and 26 male, aged 34.3 (2.8) years. Immunohistochemical analysis was performed on paraffin wax embedded material using monoclonal antibodies directed against the proliferation associated nuclear antigen Ki-67 and cyclin A.

RESULTS

The median Ki-67 LI was 8.6% (interquartile range, 4.4%-14.0%). Ki-67 LI was significantly higher in tumours with a heavy inflammatory reaction and diabetes insipidus at presentation, whereas other clinical and histological features were not associated with the proliferation index. There was a strong linear correlation between Ki-67 LI and cyclin A LI (r = 0.77; p<0.0001); therefore, cyclin A LI showed the same clinical and histological relations described for Ki-67 LI. Recurrence of craniopharyngioma occurred in 13 of 46 patients (28.3%). The median Ki-67 LI in the 13 recurrent craniopharyngiomas (9.0%) was not significantly different from that of non-recurring tumours (7.9%). Cyclin A LI was also not associated with the risk of relapse.

CONCLUSIONS

This study confirms the great variability of proliferative activity in craniopharyngiomas. Ki-67 and cyclin A LIs were associated with the presence of a heavy inflammatory reaction and diabetes insipidus, but did not correlate with the long term risk of tumour regrowth.

Meningioma presenting with Cushing's syndrome: an unusual clinical presentation

We report a patient with a meningioma presenting with Cushing's syndrome, an unprecedented paraneoplastic presentation. Molecular studies, bioassay, and high-performance liquid chromatography of tumor specimens demonstrated the synthesis and secretion of bioactive corticotropin-releasing hormone. To our knowledge, this appears to be the first report of a hormone-secreting meningioma and, further, the first clearly proven case of Cushing's syndrome due to ectopic corticotropin-releasing hormone secretion without concomitant corticotropin production.

Primary brain CD30+ ALK1+ anaplastic large cell lymphoma ('ALKoma'): the first case with a combination of 'not common' variants

BACKGROUND

Primary central nervous system lymphomas (PCNSLs) are rare tumors, mostly represented by diffuse large B cells. PCNSLs with a T phenotype are less frequently reported; even rarer are anaplastic large cell lymphomas (ALCLs). PCNSL ALCLs are commonly represented, like their systemic counterpart, by a variably prevalent amount of large pleomorphic tumor cells ('hallmark cells'), and this feature enhances their recognition. Patient and methods We report the first case of primary brain CD30+ ALK-1+ ALCL with a T-cell phenotype, showing the combination of both the 'lymphohistiocytic' and the 'small cell' variants of the disease. A few elements consistent with 'hallmark cells' were recognizable. However, these cells were never prominent, increasing diagnostic difficulties. Immunohistochemistry results were critical for the correct interpretation. Our findings also differ from the majority of PCNSL ALCLs for the absence of tumor necrosis and the lack of prominent mitotic activity. The neuroimaging picture was not specific. A comparison with literature data concerning the clinical/instrumental features shows a very frequent meningeal involvement in PCNSL ALCLs, in contrast to the majority of PCNSLs.

CONCLUSION

The occurrence of such a rare form of ALCL may widen the spectrum of differential diagnoses in PCNSL and their recognition may allow a rapid diagnosis, thus encouraging adequate treatment, which should take into account the high rate of meningeal involvement observed in these cases.

Effects of octreotide treatment on the proliferation and apoptotic index of GH-secreting pituitary adenomas

To investigate the effects of octreotide administration on the growth rate of GH-secreting pituitary adenomas, we measured both the Ki-67 labeling index (LI) and the apoptotic index in tumor specimens from octreotide-treated or matched untreated acromegalic patients. Thirty-nine patients who received octreotide until the day of or the day before surgery and 39 untreated patients matched for sex, age, tumor size, extension, and invasiveness were studied. Immunocytochemical analysis was performed on paraffin-embedded material using a monoclonal antibody (MIB-1) directed against a proliferation-associated nuclear antigen, Ki-67, to measure the growth fraction. Apoptosis was assessed by the terminal deoxynucleotidyl transferase-mediated deoxy-UTP nick endlabeling method, using a monoclonal antibody recognizing areas of DNA fragmentation. The Ki-67 LI and apoptosis were counted on separate slides in at least 1000 evaluable cells. Octreotide-treated patients showed a lower Ki-67 LI (1.8 +/- 0.3%) than untreated controls (3.8 +/- 0.7%; P < 0.02). Overall, the mean Ki-67 LI of treated patients was 53% lower than that in untreated patients. The antiproliferative effect of octreotide occurred independently of tumor extension and invasiveness. Octreotide-treated and untreated patients showed similar apoptotic indexes (0.6 +/- 0.2% and 0.8 +/- 0.3%, respectively). There was a positive correlation between the Ki-67 LI and the apoptotic index (r = 0.29; P < 0.03). Our study demonstrates that acromegalic patients receiving chronic octreotide treatment have a lower value of the proliferation marker Ki-67, but no significant difference in the apoptotic index compared with matched untreated patients. The antiproliferative effect of octreotide on GH-secreting adenomas should imply a lower risk of tumor growth during long-term chronic treatment with the drug.

Primary angiitis of the central nervous system: serial MRI of brain and spinal cord

MRI findings in primary angiitis of the central nervous system (PACNS) are highly variable, ranging from normal to diffusely abnormal. We describe brain and spinal cord abnormalities in patients with PACNS and changes over time, to provide criteria which could be useful for differential diagnosis. We reviewed six patients, with a final diagnosis of PACNS, who underwent serial contrast-enhanced brain and spinal MRI. Follow-up ranged from 12 to 60 months. Brain MRI showed multiple small abnormalities in all patients, giving high signal on T2-weighted images, focal or diffuse, mainly in deep and subcortical white matter; four patients had both supra- and infratentorial lesions. On the initial MRI, in five patients, almost 90% of the abnormal foci showed contrast enhancement. Virchow-Robin perivascular spaces were enlarged and simultaneously enhancing in four patients. Three patients also had spinal cord abnormalities, in the cervical and thoracic segments in two, and exclusively cervical segment in one. Two patients had brain biopsy-proven PACNS; in the remainder, the diagnosis of PACNS was presumptive, considering similarities in clinical and MRI features and MRI follow-up. On MRI, after steroid and immunosuppressive therapy, a significant decrease in the number and size of the abnormalities, enhancing and nonenhancing and of enhancing perivascular spaces was observed. Simultaneous enhancement of brain and spinal cord lesions and of perivascular spaces, at the onset of the disease, which resolves during follow-up, can therefore suggest PACNS.

Combined treatment with high-dose methotrexate, vincristine and procarbazine, without intrathecal chemotherapy, followed by consolidation radiotherapy for primary central nervous system lymphoma in immunocompetent patients

OBJECTIVES

To assess the feasibility and the activity, as well as the efficacy to treat meninges, of chemotherapy (CHT) containing high-dose methotrexate (HD-MTX) followed by radiation therapy (RT), without intrathecal CHT, in patients with primary central nervous system lymphoma.

METHODS

Eligibility criteria were histologically proven diagnosis, disease limited to the CNS, age < or = 70, ECOG performance status < or = 3, HIV-negative and no prior treatment. Thirteen patients (1996-1999; median age 54 years) received two courses of vincristine 1.4 mg/m2 day 1, MTX 3 g/m2 days 3 and 10 and procarbazine 100 mg/m2 days 1-14 every 4 weeks. Patients who achieved a complete remission were referred to RT, those with progressive disease were excluded from further study; all the remaining patients received a third course of CHT followed by RT.

RESULTS

Twelve patients responded to CHT (overall response rate = 92%, complete response rate = 77%): 9 underwent consolidation RT, 3 did not. Two patients experienced severe acute toxicity; lethal pulmonary thromboembolism and transient renal failure. Five patients relapsed: 2 after CHT and 3 after RT. Relapse was local in all cases, with a case of concomitant hepatic involvement. No cases of ocular or meningeal relapse were observed. In contrast to high-dose cytarabine-containing CHT, salvage therapy with temozolomide produced good results. Two patients died of treatment-related neurotoxicity. Six patients are alive with a median follow-up of 17 months, and a 2-year overall survival (OS) of 61%. The median survival of the 9 patients who completed the planned treatment is 25+ months with a 2-year OS of 80%.

CONCLUSIONS

HD-MTX, procarbazine and vincristine followed by RT, without intrathecal therapy, produce similar results with respect to other HD-MTX-containing regimens. These results seem to suggest that adequate meningeal treatment is possible without intrathecal drug delivery, even in CSF-positive patients. Corroborating data from a larger series are, however, necessary. Temozolomide should be tested in relapsed patients in a phase II prospective trial.

Spinal cord involvement in primary angiitis of the central nervous system: a report of two cases

SUMMARY

We report two patients with suspected primary angiitis of the CNS who underwent serial contrast-enhanced MR imaging of the spinal cord. MR abnormalities were multiple and enhancing, and located within the cervical and thoracic cord. Brain MR findings and brain biopsy specimens were positive for primary angiitis of the CNS. On follow-up MR studies, obtained after steroid and immunosuppressive therapy, a significant decrease in the number and size of the enhancing and nonenhancing abnormalities was observed, along with clinical improvement. Numerous small and enhancing abnormalities with a primarily posterior location, seen at the onset of the disease and resolved on follow-up studies, may be considered suggestive of a diagnosis of primary angiitis of the CNS.

Proliferation index of nonfunctioning pituitary adenomas: correlations with clinical characteristics and long-term follow-up results

OBJECTIVE

The recurrence of nonfunctioning pituitary adenomas (NFPAs) after surgical removal is common. The aim of our study was to investigate and correlate the growth fraction of NFPAs with clinical characteristics and long-term follow-up results.

METHODS

Tumor specimens were obtained from 101 consecutive patients with NFPAs (48 female patients and 53 male patients; mean age, 52.0 +/- 1.5 yr). Specimens were immediately fixed in 10% buffered formalin and then embedded in paraffin. The Ki-67 antigen was assessed by immunocytochemical analysis using the monoclonal antibody MIB-1. The Ki-67 antigen labeling index (LI) was determined by counting a total of at least 1,000 neoplastic nuclei.

RESULTS

The mean Ki-67 LI for the 101 patients was 2.4 +/- 0.3% (range, 0-23.0%). Only age at surgery was inversely correlated with the Ki-67 LI; sex, maximal tumor diameter, and invasiveness into the cavernous sinuses did not significantly affect the Ki-67 LI. The mean follow-up period was 39.7 +/- 2.1 months. During follow-up monitoring, 23 patients experienced tumor recurrence, after a mean period of 28.6 +/- 4.8 months. Invasiveness of the tumor on preoperative magnetic resonance imaging scans was the strongest predictor of late tumor recurrence, followed by previous pituitary surgery, younger age, and lack of postoperative radiotherapy. The Ki-67 LI had no independent prognostic value.

CONCLUSION

Our study suggests that the clinical characteristics of patients with NFPAs, except for age at surgery, are not correlated with the Ki-67 LI. Moreover, the Ki-67 LI does not seem to provide independent information to identify patients at high risk for tumor recurrence.

Acromegaly associated with a granular cell tumor of the neurohypophysis: a clinical and histological study. Case report

Acromegaly is usually caused by a growth hormone (GH)-secreting pituitary adenoma, and hypersecretion of GH-releasing hormone (GHRH) from a hypothalamic or neuroendocrine tumor accounts for other cases. The authors report on the unusual association of acromegaly with a granular cell tumor of the neurohypophysis. A 42-year-old woman with a 10-year history of acral enlargement, headache, and menstrual abnormalities was referred to our department for a suspected GH-secreting pituitary adenoma. The patient's basal GH levels were mildly elevated at 4.8 microg/L, were not suppressed in response to an oral glucose tolerance test, and increased paradoxically after administration of thyrotropin-releasing hormone. The patient's insulin-like growth factor-1 (IGF-1) level was elevated at 462 microg/L, whereas a magnetic resonance image of the sella turcica revealed an intra- and suprasellar lesion that was compatible with a diagnosis of pituitary adenoma. A transsphenoidal approach to remove the lesion, which was mainly suprasellar, was successful during a second operative attempt, resulting in the clinical and biochemical regression of the patient's acromegaly. Four months postoperatively, the patient's basal GH level was 0.9 microg/L and her IGF-1 level was 140 microg/L. Histological analysis of the operative specimen demonstrated a granular cell tumor of the neurohypophysis, which when stained proved negative for pituitary hormones and GHRH. This case represents the first reported association between a granular cell tumor of the neurohypophysis and acromegaly. Granular cell tumor of the neurohypophysis could be added to the restricted list of neoplastic causes of acromegaly secondary to hypersecretion of a GH-releasing substance.

Glial cyst of the pineal gland: case report and considerations about surgical management

Symptomatic glial cyst of the pineal gland are rare lesions. Origin, natural history and factors leading to cyst enlargement are not completely clear; thus management remain uncertain in some cases. We report a case of symptomatic glial cyst and analyze the implication for surgery. Surgical management is indicated in patients presenting hydrocephalus, mass effect or symptoms related to mesencephalic dysfunction. The infratentorial supracerebellar approach represent the first choice for this condition allowing easy orientation with wide exposure of the tumor and good visibility of deep venous systems that may be preserved. Size of the tumor is a key element in evaluation of the treatment and the appropriate course for asymptomatic cyst less than 1 cm in size consist of conservative management. Periodic follow up is always indicated.

Determination of the proliferation and apoptotic index in adrenocorticotropin-secreting pituitary tumors : comparison between micro- and macroadenomas

We investigated the growth fraction and cell loss fraction in a large group of patients with Cushing's disease subdivided according to tumor size. Fifty-one patients, 8 males and 43 females, aged 12 through 61 years (mean age 34.6 +/- 1.5 years), were studied. Thirty-six patients had a microadenoma and the remaining 15 a macroadenoma. Immunohistochemical analysis was performed on paraffin-embedded material using a monoclonal antibody (MIB-1) directed against a proliferation-associated nuclear antigen, Ki-67, to measure the growth fraction. Apoptosis was assessed by the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling method, using a monoclonal antibody recognizing areas of DNA fragmentation. Ki-67 labeling index and apoptosis were counted on separate slides in at least 1000 evaluable cells. Patients with a macroadenoma had a significantly higher value of Ki-67 index (9.3 +/- 2.7%) than patients with microadenoma (2.8 +/- 0.5%; P < 0.002), whereas the apoptotic index was not significantly different in the two groups (1.7 +/- 0.8% in macroadenomas versus 0.8 +/- 0.3% in microadenomas). Our study shows that ACTH-secreting macroadenomas are characterized by a higher cell growth fraction than microadenomas, whereas the cell loss fraction is not different. A high proliferation rate seems to play a major role in determining the progression from small to large pituitary tumors in Cushing's disease.

Human herpesvirus 6 in cerebrospinal fluid of patients infected with HIV: frequency and clinical significance

The objective was to evaluate the frequency of human herpesvirus 6 (HHV-6) DNA detection in the CSF of patients infected with HIV and its relation to brain disease and systemic HHV-6 infection. Nested polymerase chain reaction (PCR) was used to analyse CSF samples from 365 consecutive HIV infected patients with neurological symptoms. When available, plasma and brain tissues from patients whose CSF was HHV-6 positive were also studied. HHV-6 was found in the CSF of eight of the 365 patients (2.2%): two had type A and four type B; the HHV-6 variant could not be defined in the remaining two. All eight patients had neurological symptoms and signs related to concomitant opportunistic brain diseases, including cytomegalovirus (CMV) encephalitis in five patients whose CSF was also positive for CMV-DNA. Opportunistic infections but no other unexplained lesions were also found in the brain of all of the four patients who underwent neuropathological examination. Both HHV-6 and CMV were also detected in the plasma of respectively five and seven of seven patients whose CSF was HHV-6 positive. In conclusion, HHV-6 type A or B DNA was infrequently found in the CSF of HIV infected patients, in association with both CMV brain infection and systemic HHV-6 replication. However, no certain relation between HHV-6 and brain disease was found.

Usefulness of markers of cell proliferation in the management of pituitary adenomas

1. Pituitary adenomas are benign and slow-growing tumours whose clinical manifestations depend mainly on the secretory activity of the adenomatous cells. Except for prolactinomas, surgical removal of the tumour is the therapy of choice. 2. Despite extensive research on their clinical and pathophysiological aspects, few studies have explored the oncological characteristics of these rare lesions. Among these, the growth fraction of pituitary adenomas has been determined by different methods, of which the most useful are those performed in archival material. 3. The results reported in the literature show that adrenocorticotropic hormone-secreting tumours seem to be characterized by a higher proliferation index than the other types of pituitary adenomas, despite their usually small tumour size. 4. In small series of patients radiotherapy and medical treatment with dopaminergic drugs and octreotide were associated with a lower proliferation index than untreated tumours. Tumour size was not correlated with the growth fraction of the pituitary tumours, whereas invasiveness was correlated in most studies. 5. From a clinical point of view, however, the more promising utilization of the proliferation index seems to be in predicting the potential of recurrence of the tumour, thus allowing a more rational approach to follow-up and further treatment of patients with pituitary adenomas.