Marcello Ravegnani

High levels of PROM1 (CD133) transcript are a potential predictor of poor prognosis in medulloblastoma

The surface marker PROM1 is considered one of the most important markers of tumor-initiating cells, and its expression is believed to be an adverse prognostic factor in gliomas and in other malignancies. To date, to our knowledge, no specific studies of its expression in medulloblastoma series have been performed. The aims of our study were to evaluate the expression profile of the PROM1 gene in medulloblastoma and to assess its possible role as a prognostic factor. The PROM1 gene expression was evaluated by quantitative- polymerase chain reaction on 45 medulloblastoma samples by using specific dye-labeled probe systems. A significantly higher expression of PROM1 was found both in patients with poorer prognosis (P= .007) and in those with metastasis (P= .03). Kaplan-Meier analysis showed that both overall survival (OS) and progression-free survival (PFS) were shorter in patients with higher PROM1 mRNA levels than in patients with lower expression, even when the desmoplastic cases were excluded (P= .0004 and P= .002, for OS and PFS for all cases, respectively; P= .002 and P= .008 for OS and PFS for nondesmoplastic cases, respectively). Cox regression model demonstrated that PROM1 expression is an independent prognostic factor (hazard ratio, 4.56; P= .008). The result was validated on an independent cohort of 42 cases by microarray-based analysis (P= .019). This work suggests that high mRNA levels of PROM1 are associated with poor outcome in pediatric medulloblastoma. Furthermore, high PROM1 expression levels seem to increase the likelihood of metastases. Such results need to be confirmed in larger prospective series to possibly incorporate PROM1 gene expression into risk classification systems to be used in the clinical setting.

Successful isolation and long-term establishment of a cell line with stem cell-like features from an anaplastic medulloblastoma

Aims: Herein we report on the successful isolation and establishment of a novel, long‐term, primary, neurosphere‐like cell line called 1603‐MED from a 5‐year‐old boy affected by a highly aggressive anaplastic medulloblastoma. Methods: Elaboration of the new protocol for neurosphere assay is extensively discussed, together with a complete immuno‐histochemical and cytogenetic characterization of 1603‐MED. Results: Clinical course and histopathology are briefly discussed. The 1603‐MED possesses a high capacity for proliferation, CD133 expression, self‐renewal and differentiation, thus indicating that anaplastic medulloblastoma contains a subpopulation of cancer stem cells as observed in classic medulloblastoma. Conclusions: 1603‐MED provides us with the first in vitro model of anaplastic medulloblastoma that may be suitable for studying both tumour progression and the genetic mechanisms related to therapy resistance, and may lead to the development and testing of chemosensitivity and new therapeutic targets.

Sinus pericranii: diagnosis and management in 21 pediatric patients.

OBJECT Sinus pericranii (SP) is a rare venous anomaly abnormally connecting the intracranial dural sinuses with the epicranial veins. In the present study the authors aimed to clarify this clinicoradiological entity, define the role of angiography in its preoperative assessment, and suggest a diagnostic-therapeutic flow chart for management purposes. METHODS The authors retrospectively reviewed the clinical charts and neuroimages of 21 patients with SP. All patients underwent brain MRI, MR venography, and craniocerebral CT. Diagnostic digital subtraction angiography was performed in 19 of 21 patients, and the SPs were categorized as dominant (draining the majority of the intracranial venous outflow) or accessory (draining only a minority of the intracranial venous outflow). RESULTS SP was median or paramedian in 20 patients and lateral in 1 patient. There were 5 dominant and 14 accessory SPs. The dominant SPs were not treated. Among the patients with accessory SP, 4 were not treated, 2 underwent surgical ligature, and 8 were treated endovascularly (with either transvenous or percutaneous embolization). No complications were observed, and symptoms disappeared after treatment in all cases. CONCLUSIONS Accepted guidelines or recommendations concerning the management, diagnosis, and treatment of SP are still lacking. The authors define here a diagnostic-therapeutic flow chart, in which angiography plays a crucial role in the classification of SP and choice of the optimal treatment. Only accessory SP is amenable to treatment, whereas dominant SP must be preserved. The endovascular approach is becoming increasingly relevant and has proven to be safe and effective.

Cervico-medullary desmoplastic infantile ganglioglioma. An unusual case with diffuse leptomeningeal dissemination at diagnosis

Desmoplastic infantile ganglioglioma (DIG) is a rare intracranial tumor affecting newborns and infants, and generally arising in the supratentorial region. We report a case of an unusual DIG, arising at the cervico‐medullary junction, with diffuse leptomeningeal seeding at diagnosis that was treated with chemotherapy (CT) and delayed partial surgery. The case we describe demonstrates that DIG can occur in the subtentorial region and can show leptomeningeal dissemination like other low‐grade gliomas.

Novel MNX1 mutations and clinical analysis of familial and sporadic Currarino cases.

Currarino Syndrome (CS) is a rare congenital malformation characterized by three major clinical aspects: sacral anomalies, anorectal malformation and presacral mass. In familial settings the disorder is transmitted as autosomal dominant trait, with a wide phenotype variability and low penetrance. The causative gene of CS is the motor neuron and pancreas homeobox-1 (MNX1), mapped at 7q36, and coding for a transcription factor. Mutations in the MNX1 have been implicated in almost all familial but only in 30% of sporadic cases. In our cohort of 28 CS cases, 8 were familiar, 18 were sporadic and 2 were not determined cases. We performed mutational analysis of MNX1 in all cases by DNA sequencing as well as by Multiplex Ligation-dependent Probe Amplification (MLPA) in those CS cases where no MNX1 mutations were found, to exclude a MNX1 heterozygous loss. We identified 10 novel and 4 recurrent mutations. Among the novel mutations, 2 were frameshift variants (p.Ser4IlefsX52, p.Phe248SerfsX35), 6 were missense variants (p.Pro27Leu, p.Gly103Arg, p.Leu254Pro, p.Leu278Pro, p.Glu282Lys, p.Arg292Gly), one was a non-sense variant (p.Lys297X), and the last one was a synonymous variant (p.Gln290Gln). Mutated patients showed a variability of phenotypes but all share at least the association of sacral agenesis and presacral mass, and this co-occurrence can constitute a pathognomonic sign to perform MNX1 analysis. Genetic heterogeneity could be a possible explanation for some of the sporadic not mutated patients even if a mis-diagnosis could not be excluded. Finally, we provide an up-date of the more recent literature, reporting a total number of 82 MNX1-CS related mutations.

Voriconazole for cryptococcal meningitis in children with leukemia or receiving allogeneic hemopoietic stem cell transplant.

Cryptococcus neoformans is an encapsulated heterobasidiomycetous that represents a major human pathogen in immunocompromised hosts 1, but invasive cryptococcosis is a rare complication during chemotherapy in patients with acute leukemia or following allogeneic hemopoietic stem cell transplant (HsCT) 2-6. The clinical picture of C. neoformans infections varies from asymptomatic colonization of the respiratory tract to disseminated disease, with meningitis being the most frequent clinical picture 1. Amphotericin B is the golden standard therapy for cryptococcosis, and its association with flucytosine leads to more rapid clearance of the fungus from the cerebrospinal fluid (CsF) 7,8. After treating the invasive infection, long term prophylaxis is required in patients persistently immunocompromised, and fluconazole represents the drug of choice 8. Other triazoles, such as itraconazole and voriconazole, have been proven to be active in vitro against C. neoformans 9. We report two cases of invasive C. neoformans meningitis infections in immunocompromised children who were successfully managed with voriconazole. Case 1: The first patient was a 6-year-old girl affected with acute lymphoblastic leukemia who developed pneumonia with severe acute respiratory insufficiency that required mechanical ventilation during administration of high dose dexamethasone for the treatment of her leukemia. Blood cultures showed the presence of yeasts that were subsequently identified as C. neoformans, and the search for the cryptococcal antigen in the serum was positive. she received antifungal therapy with liposomal amphotericin B (3 mg/kg/q24 h) that led to an improvement in her condition. After 3 weeks of this treatment, serum antigen became negative and fluconazole prophylaxis (10 mg/kg/q24 h) was started. One week later, fever reappeared and serum cryptococcal antigen became positive again. she received liposomal amphotericin B at the same dosage for another week and achieved negative antigen, but abdominal ultrasound demonstrated the presence of spleen nodules. Moreover, cryptococcal antigen was also positive in the CsF despite the absence of clinical signs of central nervous system involvement. since the patient desired to be discharged from the hospital, voriconazole was administered (7 mg/kg q12 h for 3 days, then 200 mg q12 h orally, on empty stomach) because of the availability of an oral formulation that allowed good compliance and considering its in vitro activity, ability to cross the blood-brain barrier, the failure of fluconazole prophylaxis and the persistence of antigen in the CsF. Cryptococcal antigen in the CsF resulted negative after 10 days of voriconazole. This drug was administered until 7 months after elective discontinuation of chemotherapy without any reactivation of the infection or any adverse effects. The patient relapsed with her acute lymphoblastic leukemia 2 months after discontinuation of voriconazole. At this time, cryptococcal antigen resulted negative both in the blood and CsF. she received an allogeneic HsCT from her brother after a myeloablative-conditioning regimen including body irradiation. During the first 100 days after HsCT she received fluconazole as prophylaxis (6 mg/kg/q24 h) for invasive mycosis on the basis of our standard procedures, and C. neoformans was never again detected in the blood or in the CsF. Case 2: The second patient was an 18-year-old boy with incomplete immunological reconstitution (CD4+ lymphocytes, 9%, 54/cmm and absence of CD19+/CD20+ lymphocytes) after alternative donor HsCT. He developed sudden fever associated with impaired consciousness, headache, blurred vision and rash 36 months after HsCT. Magnetic Resonance imaging showed the presence of mild intracranial hypertension and C. neoformans was isolated from cerebrospinal fluid. in view of the fact that the patient RepRint

Bilateral germinoma of the basal ganglia

Germinoma arising in the bilateral basal ganglia is exceedingly rare, with only five cases reported to date. Owing to non‐specific clinical findings and the frequent presence of ill‐defined abnormalities without a definite tumor mass on neuroimaging, the diagnosis can be difficult. We describe a case in which magnetic resonance spectroscopy (MRS) findings suggested a tumor and supported the decision to perform biopsy of the lesion. Pediatr Blood Cancer 2008;50:177–179.

Cystic angiomatosis of the craniocervical junction associated with Chiari I malformation

IntroductionCystic angiomatosis of the skull and spine is an exceptionally rare, benign vascular lesion. Both the vertebral bones and the skull may be affected. Diagnosis and treatment of this disease is multidisciplinary.DiscussionHistological examination is ultimately required to make a diagnosis. When the craniocervical junction is involved, the site of biopsy should be carefully selected so as to reduce procedure-related morbidity, including cerebrospinal fluid leakage and spinal deformity. We present a case report of a 4-year-old boy with cystic angiomatosis of the skull base and upper cervical spine associated with a Chiari I malformation and provide a review of the pertinent literature.

Intracerebral schwannoma in a child

This 7-year-old boy presented with generalized seizures and normal physical and neurological examination. MRI (Fig. 1) revealed a left parietooccipital intraaxial mass surrounded by abundant oedema...

Post-chemotherapy maturation of a pineoblastoma

Pineoblastoma is defined as a highly malignant embryonal tumour of the pineal gland [3]. As conveyed by the adjective embryonal, it is a small blue cell tumour resembling a PNET [2, 3]. It is found at one end of a morphological spectrum, at the other end of which lies the pineocytoma. In between, amidst poorly and better differentiated tumours, are parenchymal pineal tumours of intermediate differentiation, consisting of a variety of transitional types [2, 3]. Seldom are the latter composed of both poorly and well differentiated tissues. Tumours of intermediate differentiation and pineocytomas are rare in the first decade, while pineoblastomas occur in the first and second decades, though rarely in infants. We describe a case of infantile pineoblastoma showing diffuse neuronal maturation after treatment. An 8-month-old male developed symptoms related to increased intracranial pressure. Neuroimaging revealed a pineal tumour with hydrocephalus, without craniospinal seeding (Fig. 1a–c). CSF cytology was negative. Third ventriculostomy was performed owing to the hydrocephalus; after a few days, several biopsies from distinct parts of the tumour were obtained. Histologically, the tumour was composed of small cells with round to oval nuclei and scant, slightly basophilic cytoplasms, embedded in a myxoid matrix (Fig. 2a, c). The nuclei varied moderately in size, with only slightly irregular contours and small eosinophilic nucleoli. A few Homer-Wright rosettes were seen. Neither calcifications nor necrosis were encountered. Mitotic index was 7/10 HPF; labelling index was 30% (Fig. 2g). Tumour cells expressed chromogranin A (Fig. 2e), synaptophysin, and focally NeuN. GFAP was negative. INI1 expression was retained. The patient underwent intensive induction chemotherapy, followed by high-dose chemotherapy with peripheral blood stem cell reinfusion. Neuroimaging demonstrated reduction of tumour volume (Fig. 1d–f). Thereafter, a two-step subtotal resection was performed. This time, the histology showed a hypocellular tumour composed of a mixture of small round cells with neurocytic appearance and larger, often bi-nucleated, ganglion cells (Fig. 2b–d). No mitoses were present; labelling index, 1% (Fig. 2h). The tumour cells expressed neurofilament protein (Fig. 2f), synaptophysin, and NeuN. Chromogranin A and GFAP were negative. Fractional conformal radiotherapy on the tumour bed concluded the treatment. The only sequela was mild converging strabismus with diplopia. Remission status was ongoing 9 months after the end of therapy. In this case a difference between the first biopsies and those performed after therapy appears clearly. At first surgery, the lesion fulfilled the criteria of an embryonal small cell tumour with a neuronal phenotype consistent, on the basis of location, with a pineoblastoma. The latest biopsies disclosed a neuronal tumour composed of a mixture of ganglion and neurocytic cells (the final diagnosis was low-grade neuronal tumour). P. Nozza (&) Unità Operativa di Anatomia Patologica, Istituto Giannina Gaslini, Largo Gerolamo Gaslini, 5, 16148 Genoa, Italy e-mail: paolonozza@ospedale-gaslini.ge.it