[Two Cases of Primary Intracranial Solitary Fibrous Tumor:Genetic Examination of NAB2-STAT6 Fusion and Its Association with Hemangiopericytoma].

Using whole exome and transcriptome sequencing, NAB2-STAT6 gene fusions have recently been identified in patients with solitary fibrous tumors (SFT). We report two cases of SFT in which NAB2-STAT6 fusions were identified. The patients were a 32-year-old man with a parasagittal tumor involving the superior sagittal sinus, and a 40-year-old man with a cerebellar convexity tumor partially involving the transverse sinus. Their tumors were gross totally resected and diagnosed to be SFT according to the following pathological findings:the tumors were composed of spindle cells with a patternless architecture, with prominent stromal collagen and staghorn vessels. An immunohistochemical study yielded positive results for CD34, CD99, and Bcl-2 and negative results for EMA, GFAP, and S100. The MIB-1 indexes were 13 and 7%, respectively. NAB2-STAT6 fusions were detected in both cases with a common fusion variant, NAB2ex6-STAT6ex16/17. We also identified NAB2-STAT6 fusions in two hemangiopericytomas diagnosed in the past with a common variant of NAB2ex6-STAT6ex16/17. These findings suggest that solitary fibrous tumor and hemangiopericytoma may be diagnosed based on the presence of NAB2-STAT6 fusion, and not classified separately because of the same genetic background.

Cranial molding helmet therapy and establishment of practical criteria for management in Asian infant positional head deformity.

BACKGROUND: The growing number of infants with deformational plagiocephaly (DP) has raised clinical questions about which children, at what age, and how molding helmet therapy (MHT) should be performed especially in Japan. METHODS: A total of 1,011 Japanese pediatric head deformity infants had undergone MHT after being diagnosed with non-synostotic DP. Three ratios of left to right comparison (anterior, posterior, and overall) were created and analyzed comparing age of starting treatment, helmet wearing period, and severity of skull deformity before with after MHT. RESULTS: The averages of head symmetry ratios after treatment in all groups (for the occipital region) showed apparent improvement; t(930) = -60.86, p = 0.000. (t(932) = -57.8, p = 0.000.) In the "severe" deformation group, the earlier the treatment was started, the higher symmetry ratio recovery was obtained. Treatment was especially effective when started in 4-month-old infants. In contrast to the "severe" group, the "mild" deformation group showed that MHT was most effective if treatment started before 6 months of age. Again, the earlier the treatment was started, the higher symmetry ratio was achieved, but compared to the "severe" group, it had a modest effect when treatment was started in infants older than 8 months. CONCLUSION: This is the first large-scale molding helmet study reporting the method and efficacy in Japanese infants. It demonstrated that despite the structural and physiological differences from infants of other races, molding helmet therapy is effective in Asian-born infants, provided that intervention timing and recognition conditions are met.

[A case of cavernous sinus epidermoid: anatomical classification and surgical approach].

Epidermoid rarely appears in the cavernous sinus. We encountered a 41-year-old man with left abducens nerve palsy. A round-shaped, low-density lesion on CT was located lateral to the left cavernous sinus with a compressed and thinned lateral wall of the sphenoid sinus. We could not identify cranial nerves in the cavernous sinus, which was found to be packed with a non-enhanced, high-intensity tumor on both T1 and T2 MRI. Part of the tumor capsule and its pearly contents were removed with an intradural subtemporal approach, and an inner membranous layer with cranial nerves and a tumor capsule were seen at the bottom of the tumor cavity. Postoperatively, complete cure was achieved. Reviewing similar cases, we found 18 cavernous sinus epidermoids:extracavernous type in 5;interdural in 10;and intracavernous in 3. The interdural type could be further divided into two subtypes:superficial cavernous sinus and inner membranous types. The present case belongs to the former. Frontotemporal and subtemporal procedures via both intra- and extradural approaches are relatively safe for lesions except for the intracavernous type, because cranial nerves are not located in the lateral wall of the tumor. MRI provides more useful information on cranial nerves and aid in choosing a better treatment strategy.

A highly sensitive and specific chemiluminescent enzyme immunoassay for placental alkaline phosphatase in the cerebrospinal fluid of patients with intracranial germinomas.

BACKGROUND: Placental alkaline phosphatase (PLAP) in cerebrospinal fluid (CSF) has been proposed as a tumor marker for intracranial germinomas. The purpose of the present study was to develop a sensitive assay for measuring CSF PLAP and to evaluate the clinical significance of PLAP in patients with germinomas. METHODS: A chemiluminescent enzyme assay for PLAP was developed using an anti-human-PLAP monoclonal antibody. PLAP concentrations were determined in 37 controls, 36 germinomas, 3 nongerminomatous germ cell tumors, 21 gliomas and 12 other brain tumors. RESULTS: The assay detection limit was 5 pg/ml. The median PLAP concentration in the control group was below the detection limit. Significantly higher PLAP levels were detected in all 36 germinoma patients, with values ranging from 16 to 3,700 pg/ml. The high PLAP concentrations of 17 germinoma patients decreased to below the detection limit after complete remission had been achieved with radiochemotherapy. The sensitivity and specificity of PLAP for germinomas were 94 and 97%, respectively, with a cutoff value of 30 pg/ml. CONCLUSIONS: The results of this study suggest that the determination of CSF PLAP by the chemiluminescent method described here provides a clinically useful tumor marker for the diagnosis and monitoring of intracranial germinomas.

Shared molecular targets in pediatric gliomas and ependymomas.

BACKGROUND: Recent advances in multidisciplinary treatment approaches have improved the overall prognosis of pediatric brain tumors, but some patients remain refractory to treatment and do poorly. Several molecularly targeted therapies are under development for the treatment of brain tumors, and high-grade gliomas in adults are a particular area of study. PROCEDURE: To better understand if these new therapies can be used in pediatric populations, we examined the expression of the following seven marker genes involved in signaling pathways targeted by new therapies: ß-catenin, suppressor of fused (SUFU), erythroblastic leukemia viral oncogene homolog (ERBB) 2, platelet-derived growth factor receptorα (PDGFRα), proliferating cell nuclear antigen (PCNA), secreted protein acid and rich in cysteine (SPARC), and granulocyte colony-stimulating factor receptor (G-CSFR). Samples from 27 patients with the primitive neuroectodermal tumor (PNET)/medulloblastomas (MBs) (n = 8), ependymomas (n = 5), or gliomas (n = 14) were assessed by quantitative real-time PCR. [Correction made here after initial online publication]. We assigned an EXP score to compare across samples and determined the levels of gene expression among tumor cell types. RESULTS: Gene expression varied among the different tumors, but, within a tumor type, clear expression patterns were seen. The expression of SUFU, ERBB2, and PCNA in metastatic MBs were greater than that seen in non-metastatic MBs. Most glioma cases highly expressed PDGFRα and G-CSFR. Additionally, the expression patterns of gliomas and ependymomas were similar (r = 0.77, P = 0.04), but PNET/MBs substantially differed from gliomas (r = -0.37, P = 0.41) or ependymomas (r = 0.23, P = 0.62). CONCLUSIONS: The development of new drugs targeting up-regulated pathways may be useful for the treatment of pediatric brain tumors. As new drugs are developed, gliomas and ependymomas may be treated with similar compounds.

A case of TSH-producing adenoma treated with octreotide in combination with thiamazole for the control of TSH and thyroid hormones after trans-sphenoidal neurosurgery.

While TSH-producing adenoma (TSHoma) is rare, the diagnosis is often delayed because the clinical features are heterogeneous. The patient was a 69-year-old woman who had been referred to the Yachiyo Medical Center in August 2008, because of dyspnea, loss of appetite, weight loss of 10 kg, and diarrhea that lasted 4 years. We diagnosed this patient with pituitary TSH-producing macroadenoma. Thyroid hormone concentration was increasing although the serum TSH level was within a normal range after trans-sphenoidal surgery. We considered that because of enlargement of the thyroid gland due to long-term stimulation by TSH, a low concentration of TSH could stimulate the thyroid gland to produce excess T3 or T4. The somatostatin analogue, octreotide was used to control the TSHoma and serum TSH concentration but not thyroid hormone. The octreotide in combination with thiamazole treatment for 14 months controlled thyroid hormone concentration and decreased the thyroid mass, and ultimately, the thiamazole could be stopped. To date, the use of combination therapy of octreotide with thiamazole in patients with remaining TSH-producing adenoma without Basedow's disease is rare, and we suggest that this treatment is one of the therapeutic means to treat recurrence of TSH-producing adenoma after surgery with progressive complications or large thyroid gland.

A case-case study of mobile phone use and acoustic neuroma risk in Japan.

Results of case-control studies of mobile phone use and acoustic neuroma have been inconsistent. We conducted a case-case study of mobile phone use and acoustic neuroma using a self-administered postal questionnaire. A total of 1589 cases identified in 22 hospitals throughout Japan were invited to participate, and 787 cases (51%) actually participated. Associations between laterality of mobile phone use prior to the reference dates (1 and 5 years before diagnosis) and tumor location were analyzed. The overall risk ratio was 1.08 (95% confidence interval (CI), 0.93-1.28) for regular mobile phone use until 1 year before diagnosis and 1.14 (95% CI, 0.96-1.40) for regular mobile phone use until 5 years before diagnosis. A significantly increased risk was identified for mobile phone use for >20 min/day on average, with risk ratios of 2.74 at 1 year before diagnosis, and 3.08 at 5 years before diagnosis. Cases with ipsilateral combination of tumor location and more frequently used ear were found to have tumors with smaller diameters, suggesting an effect of detection bias. Furthermore, analysis of the distribution of left and right tumors suggested an effect of tumor-side-related recall bias for recall of mobile phone use at 5 years before diagnosis. The increased risk identified for mobile phone users with average call duration >20 min/day should be interpreted with caution, taking into account the possibilities of detection and recall biases. However, we could not conclude that the increased risk was entirely explicable by these biases, leaving open the possibility that mobile phone use increased the risk of acoustic neuroma.

High-dose chemotherapy followed by autologous and allogeneic peripheral blood stem cell transplantation for recurrent disseminated trilateral retinoblastoma.

INTRODUCTION: Trilateral retinoblastoma (TRb) is an intracranial neurogenic tumor associated with unilateral or bilateral retinoblastoma and has very poor prognosis. Patients typically die from leptomeningeal tumor dissemination. CASE REPORT: A 3-year-old girl who had been diagnosed with TRb had a disseminated relapse after a tumorectomy, cerebrospinal irradiation, and conventional chemotherapy. The disseminated tumor disappeared after the first autologous peripheral blood stem cell transplantation (PBSCT) with high-dose melphalan and thiotepa. During the second complete remission, a second autologous PBSCT with high-dose busulfan and melphalan was performed. Seven months after the first PBSCT, the second relapse occurred, and we subsequently performed an allogeneic PBSCT with myeloablative chemotherapy consisting of melphalan, thiotepa, and cyclophosphamide. The patient showed clinical improvement after the allogeneic PBSCT. CONCLUSION: Although high-dose chemotherapies have a curative effect for some patients with TRb, the prognoses of disseminated tumors are still poor. Further examination of the high-dose chemotherapy is necessary for the time, the conditioning drugs, and the hematopoietic stem cell sources.

Double high-dose chemotherapy followed by autologous peripheral blood stem cell transplantation for primary disseminated medulloblastoma: a report of 3 cases.

We performed double high-dose chemotherapy followed by peripheral blood stem cell transplantation (PBSCT) in 3 children with medulloblastoma and primary leptomeningial dissemination, including spinal metastasis. After resection of the main tumor mass, 30.6 Gy whole craniospinal radiation therapy and 4 or 5 courses of conventional chemotherapy with vincristine (1.5 mg/m), carboplatin (560 mg/m), ifosfamide (9000 mg/m), and etoposide (500 mg/m), and 2 courses of high-dose thiotepa (680 mg/m) and melphalan (240 mg/m) therapy with PBSCT were administered. Two patients with low erythroblastic leukemia viral oncogene homolog 2 (ERBB2) gene expression achieved long-term survival (41 mo and 40 mo) but the patient with high ERBB2 expression relapsed 9 months after the second PBSCT.

Power-frequency magnetic fields and childhood brain tumors: a case-control study in Japan.

BACKGROUND: The strength of the association between brain tumors in children and residential power-frequency magnetic fields (MF) has varied in previous studies, which may be due in part to possible misclassification of MF exposure. This study aimed to examine this association in Japan by improving measurement techniques, and by extending measurement to a whole week. METHODS: This population-based case-control study encompassed 54% of Japanese children under 15 years of age. After excluding ineligible targeted children, 55 newly diagnosed brain tumor cases and 99 sex-, age-, and residential area-matched controls were included in the analyses. The MF exposures of each set of matching cases and controls were measured in close temporal proximity to control for seasonal variation; the average difference was 12.4 days. The mean interval between diagnosis and MF measurements was 1.1 years. The weekly mean MF level was defined as the exposure. The association was evaluated using conditional logistic regression analysis that controlled for possible confounding factors. RESULTS: The odds ratios (95% CI) for exposure categories of 0.1 to 0.2, 0.2 to 0.4, and above 0.4 microT, against a reference category of <0.1 microT, were 0.74 (0.17-3.18), 1.58 (0.25-9.83), and 10.9 (1.05-113), respectively, after adjusting for maternal education. This dose-response pattern was stable when other variables were included in the model as possible confounding factors. CONCLUSIONS: A positive association was found between high-level exposure-above 0.4 microT-and the risk of brain tumors. This association could not be explained solely by confounding factors or selection bias.

Optimal treatment strategy for craniopharyngiomas based on long-term functional outcomes of recent and past treatment modalities.

Although many authors have described treatment strategies for craniopharyngiomas, the optimal treatment of craniopharyngiomas remains controversial. This study aimed to define an adequate surgical strategy for craniopharyngiomas by reviewing the long-term functional performance of patients treated by current and past treatment modalities. Fifty-five patients with longer than 5 years of follow-up were selected for the present long-term study. The duration of follow-up ranged from 5.5 to 33 years (median, 14.8 years). There were 28 adult patients (14 males; median age, 44.4 years) and 27 children younger than 16 years of age (15 males; median age, 8.1 years). The patients were divided into the following treatment groups: single surgery (group A; n=14 multiple surgeries (group B; n=8), surgery or surgeries followed by radiotherapy (group C; n=23), surgery or surgeries (partial removal) followed by radiotherapy + additional treatments (multiple surgeries and/or re-irradiation; group D; n=10). In addition to the routine assessments of neurological, endocrine, and visual outcomes, the level of daily functioning was analyzed using the Karnofsky Performance Scale (KPS). Statistical analysis of relationship between KPS score and treatment mode demonstrated that group D had a significantly lower KPS score (F=5.82, p=0.0017). Furthermore, mortality, cognitive function, and visual function were significantly better in groups A, B, and C than in group D. Multiple regression analysis demonstrated that cognitive dysfunction, visual disturbance, and treatment mode were independent covariates that significantly affected postoperative KPS score. Adequate primary treatment for craniopharyngiomas is important to avoid subsequent multiple treatments. Craniopharyngiomas should be removed surgically as far as possible but without further deteriorating cognitive and visual functions, either as total resection or subtotal resection with a small remnant that is controllable by radiation therapy.

[A case of gangliocytoma: a six-year follow-up of cyst formation].

We report a case of gangliocytoma at a cortical and subcortical area in the right parietal lobe. The patient had a generalized seizure at 11 years of age. The MRI shows an ill-demarcated high intensity area in T2 weighted images including an enhancing tumor of 10 mm in diameter. At first, the tumor was carefully followed up because of its small size and the surgical risk. Three years after the onset, a cyst formed at the area of the brain edema adjacent to the tumor. The cyst gradually grew to 21 mm in diameter, the edema had disappeared, and the size of the tumor became smaller (7 mm) within the next 3 years. A mural nodule, jelly-like tumor with calcification was totally removed and diagnosed as gangliocytoma. The cyst fluid was watery-clear, its wall did not contain any tumor. This is the first report of a six-year follow-up of cyst formation of gangliocytoma supporting the concept that edema is a precursor to central nervous system peritumoral cyst formation based on the similar observation of hemangioblastomas.

Coincidence of central neurocytoma and multiple glioblastomas: a rare case report.

Coincidence of parenchymal primary brain tumors of different histogenesis is extremely rare. To the best of our knowledge, the present case of simultaneous appearance of a central neurocytoma and multiple glioblastomas is the first to be reported. Multiple intraaxial brain neoplasms were disclosed in a 39-year-old man and were surgically resected. Histological diagnosis of the tumor located in the right lateral ventricle was central neurocytoma whereas two tumors of the left temporal lobe were glioblastomas. The latter were located in close proximity to the subarachnoid space, had atypical radiological appearance, and were slightly positive for synaptophysin and neurofilament protein. It can be speculated that both malignant neoplasms were, in fact, dedifferentiated central neurocytoma, which developed from distant tumor deposits. This case seems to be in agreement with the hypothesis that central neurocytoma arises from the progenitor cells with potential for both neuronal and glial differentiation. Better understanding of histogenesis of this tumor is definitely needed.

Oral administration of choline does not affect metabolic characteristics of gliomas and normal-appearing white matter, as detected with single-voxel (1)H-MRS at 1.5 T.

INTRODUCTION: The present study was done for evaluation of the possible influence of the oral administration of choline on metabolic characteristics of gliomas detected with proton magnetic resonance spectroscopy ((1)H-MRS). MATERIALS AND METHODS: Thirty patients (22 men and eight women; mean age 38 +/- 15 years) with suspicious intracranial gliomas underwent single-voxel long-echo (TR 2,000 ms, TE 136 ms, 128-256 acquisitions) (1)H-MRS of the tumor, peritumoral brain tissue, and distant normal-appearing white matter before and several hours (median, 3 h; range, 1.2-3.7 h) after ingestion of choline with prescribed dose of 50 mg/kg (median actual dose, 52 mg/kg; range, 48-78 mg/kg). Investigations were done using 1.5 T clinical magnetic resonance imager. The volume of the rectangular (1)H-MRS voxel was either 3.4 or 8 cm(3). At the time of both spectroscopic examinations, similar voxels' positioning and size and technical parameters of (1)H-MRS were used. Surgery was done in 27 patients within 1 to 68 days thereafter. In all cases, more than 80% resection of the neoplasm was attained. RESULTS: There were 12 low-grade gliomas and 15 high-grade gliomas. MIB-1 index varied from 0% to 51.7% (median, 13.8%). Statistical analysis did not disclose significant differences of any investigated metabolic parameter of the tumor, peritumoral brain tissue and distant normal-appearing white matter between two spectroscopic examinations. CONCLUSION: Single-voxel (1)H-MRS at 1.5 T could not detect significant changes of the metabolic characteristics of gliomas, peritumoral brain tissue, and distant normal-appearing white matter after oral administration of choline.

Prospective study of high-dose cabergoline treatment of prolactinomas in 150 patients.

CONTEXT: Cabergoline fails to normalize hyperprolactinemia in a considerable proportion of prolactinomas, especially macroadenomas. OBJECTIVE: We examined the effect of individualized high-dose cabergoline treatment on hyperprolactinemia in prolactinomas. PATIENTS: The study included 122 women and 28 men (93 microadenomas and 57 macroadenomas). Forty-seven had undergone transsphenoidal surgery. According to the preceding medical treatment, the participants were separated into untreated (group U; n = 60), intolerant (group I; n = 64), and resistant (group R; n = 26) groups. INTERVENTIONS: We promptly increased cabergoline dose on the basis of individual prolactin levels. Length of treatment was 1 yr. RESULTS: Cabergoline normalized hyperprolactinemia in all patients except one. The proportion of prolactin normalization in both groups U and I was 83% at 3 months and 95% at 6 months. By contrast, that in group R was 35% at 3 months and 58% at 6 months. Mean cabergoline dose in milligrams per week at the time of prolactin normalization was 2.0 +/- 0.3 in group U, 0.9 +/- 0.1 in group I, and 5.2 +/- 0.6 in group R. Prolactin normalization rate at the 3 mg/wk dose was 84% overall but only 35% in group R. Serum progesterone or testosterone levels, diminished in 122 women or 16 men, respectively, were recovered in all except one resistant and four postmenopausal or panhypopituitary patients. CONCLUSION: Individualized high-dose cabergoline treatment can normalize hyperprolactinemia and hypogonadism in nearly all prolactinomas irrespective of tumor size or preceding treatments. Hyperprolactinemia could be controlled in poor responders within 1 yr with doses higher than 3 mg/wk.

Long-term prognostic assessment of 185 newly diagnosed gliomas: Grade III glioma showed prognosis comparable to that of Grade II glioma.

OBJECTIVE: We evaluated the prognoses of newly diagnosed gliomas through WHO Grades II, III and IV to assess the overall tendency of treatment results for glioma in our institute. Furthermore, statistical analysis was performed to determine factors influencing the prognosis. METHODS: A total of 185 newly diagnosed glioma patients were operated on from 2000 to 2006. The primary endpoint was the overall survival from the date of surgery. The factors assessed as to whether they influenced the prognosis were the WHO grades of sex, age, location of the lesion, pre-operative Karnofsky Performance Status (KPS), extent of resection and whether or not radiation therapy was performed. RESULTS: The WHO grades influenced the survival significantly (P < 0.0001). The Grades II and III showed no statistically significant difference in survival (P = 0.174), whereas Grades III and IV showed a significant difference (P < 0.0001). The factor influencing survival as well as the grades was the KPS (P < 0.0001). The comparison of survival over WHO grades in the same KPS group was performed for 2 KPS groups (KPS = 100, KPS 80-90), and these also showed significant differences (P = 0.0009 and 0.0143, respectively). CONCLUSIONS: Despite the different distributions of the KPS, the Grade III glioma patients showed survival comparable to that of the Grade II. On the other hand, the Grade IV glioma patients showed significantly poorer survival compared with Grade II or III.

Successful treatment of a blood blister-like aneurysm of the internal carotid artery by trapping with a high-flow bypass.

Treatment of blood blister-like aneurysms of the internal carotid artery (ICA) is difficult because the wall of the aneurysm is fragile and there is a high risk of rebleeding. There has been no consensus on the best way to treat these aneurysms. A 32-year-old woman presented with subarachnoid hemorrhage (SAH) caused by a ruptured blood blister-like aneurysm of the ICA. The site of the aneursym was clipped. Although angiography 1week after the operation showed that the aneurysm had been treated successfully, 3 weeks after the initial operation, the aneurysm was found to have recurred to the distal side. In a second operation, the aneurysm was successfully treated by trapping with a high-flow bypass. This case shows that clipping of the rupture site can be insufficient to treat blood blister-like aneurysm of the ICA causing SAH, even if the aneurysm seems to have resolved in follow-up angiographic studies. Trapping of the ICA with a bypass, if necessary a high-flow bypass, is recommended.

Placental alkaline phosphatase levels in cerebrospinal fluid can have a decisive role in the differential diagnosis of intracranial germ cell tumors.

OBJECTIVE: Placental alkaline phosphatase (PLAP) in CSF can provide a very high diagnostic value in cases of intracranial germ cell tumors (GCTs), especially in pure germinomas, to the level of not requiring histological confirmation. Unlike other tumor markers, reliable data analysis with respect to the diagnostic value of PLAP serum or CSF levels has not been available until now. This is the first systematic and comprehensive study examining the diagnostic value of CSF PLAP in patients with intracranial GCTs. METHODS: From 2004 to 2014, 74 patients (average age 19.6 ± 10.6 years) with intracranial GCTs were evaluated using PLAP from their CSF and histological samples. Chemiluminescent enzyme immunoassay was utilized to measure CSF PLAP in the following tumor sites: pineal (n = 32), pituitary stalk, suprasellar (n = 16), basal ganglia (n = 15), intraventricular (n = 9), and cerebellar (n = 5) regions. In addition to classifying GCT cases, all patients underwent tumor biopsy for correlation with tumor marker data. RESULTS: PLAP in combination with other tumor markers resulted in extremely high sensitivity and specificity of the diagnostic value of intracranial GCTs. Intracranial GCT cases were classified into 1) germinomas, both "pure" and syncytiotrophoblastic giant cell types (n = 38); 2) nongerminomatous GCTs, choriocarcinomas (n = 9) and teratomas (n = 4); and 3) nongerminomas, other kinds of tumors (n = 23). Consequently, all patients received chemoradiation therapy based on elevation of PLAP and the histopathological results. It was also speculated that the level of PLAP could show the amount of intracranial germ cell components of a GCT. PLAP was 100% upregulated in all intracranial germinoma cases. The absence of CSF PLAP proved that the tumor was not a germinoma. CONCLUSIONS: The current study is the first systematic and comprehensive examination of the diagnostic value of the tumor marker PLAP in pediatric patients with intracranial GCT. Using the level of PLAP in CSF, we were able to detect the instances of intracranial germinoma with very high reliability, equivalent to a pathological diagnosis.

An infant case of intracranial peripheral-type primitive neuroectodermal tumor with long-term survival.

Supratentorial primitive neuroectodermal tumors (S-PNET) that develop in children have recently been classified into two types: central-type PNET (C-PNET), which has been reported over the years, and peripheral-type PNET (P-PNET), which develops intracranially and was referred to as Ewing's sarcoma in the past. P-PNET is fundamentally a malignant tumor, but the patient reported here represents a case of long-term survival from onset without recurrence. At the age of 21 months, a male infant developed a cranial bone deformity and symptoms of high intracranial pressure. A CT scan revealed a cystic tumor attaching to the falx, and cyst drainage operation was immediately performed. The intracranial tumor was then resected. The tumor was an intradural extramedullary tumor, and it was totally excised with the falx attachment. The tumor was initially diagnosed as a neuroblastoma, and postoperative treatment consisted of administration of radiotherapy and chemotherapy using cyclophosphamide and vincristine. Twenty years have now passed without any recurrence. Recent repeated performance of histopathological analysis resulted in a diagnosis of P-PNET. In recent years, studies in molecular biology have demonstrated that P-PNET involves the EWS-FLI1 chimeric gene, and immunohistochemical staining has shown P-PNET to be MIC2 positive. P-PNET also differs from C-PNET with regard to prognosis, and for this reason it is believed that P-PNET and C-PNET should be considered separate entities. That is, in spite of the fact that P-PNET is a malignant tumor, patient survival can be comparatively long. Because P-PNET originates intracranially, it is fundamentally an intradural extramedullary tumor. For this reason, treatment should consist of surgical excision that is as complete as possible, followed by appropriate radiotherapy and chemotherapy. This approach can be expected to result in the patient's long-term survival.

Management and prognosis of cysts developed on long-term follow-up after Gamma Knife radiosurgery for intracranial arteriovenous malformations.

BACKGROUND: Delayed cyst formation is a well-recognized complication after radiosurgery for intracranial AVM. The objective of the present study was the evaluation of the different management options for these lesions and the corresponding prognosis of patients. METHODS: Between 2000 and 2005, 12 patients with intracranial AVM initially treated by GKR were reevaluated at Tokyo Women's Medical University because of delayed cyst formation in the vicinity of the target area. There were 7 men and 5 women. The mean age of the patients was 31.8 years at the time of GKR and 41.1 years at the time of complication. The average period between treatment and diagnosis of the complication constituted 6.7 years. All AVMs had lobar location and showed complete angiographic obliteration after GKR. RESULTS: The most common neurological signs and symptoms at the time of cyst presentation were headache (10 cases) and seizures (4 cases). Two patients were asymptomatic. Three patients underwent surgery soon after the diagnosis of the cyst, whereas initial observation was done in another 9. Among the latter, 5 patients had to be treated surgically thereafter because of persistent or aggravated neurological symptoms associated with radiological cyst expansion. Four other patients, including both asymptomatic ones, are in stable condition without surgery. Follow-up after treatment of the cyst varied from 7 to 60 months (average, 34.3 months). All patients are in good condition. CONCLUSIONS: Although delayed formation of cysts after GKR for intracranial AVM should be considered as a complication of the radiosurgical treatment, it has a relatively good prognosis. Observation can be recommended as initial option for compensated and asymptomatic patients.