Detailed dynamical features of the slow hydration water in the vicinity of poly(ethylene oxide) chains.

Poly(ethylene oxide) (PEO) is a well-known biocompatible polymer and has widely been used for medical applications. Recently, we have investigated the dynamic behavior of hydration water in the vicinity of PEO chains at physiological temperature and shown the presence of slow water with diffusion coefficient one order of magnitude less than that of bulk water. This could be evidence for the intermediate water that is critical for biocompatibility; however, its detailed dynamical features were not established. In this article, we analyze the quasi-elastic neutron scattering from hydration water through mode distribution analysis and present a microscopic picture of hydration water as well as its relation to cold crystallization.

Treatment outcomes of proton beam therapy combined with retrograde intra-arterial infusion chemotherapy for locally advanced oral cancer in the elderly.

The aim of this study was to evaluate the therapeutic efficacy and safety of proton beam therapy combined with retrograde intra-arterial infusion chemotherapy in elderly patients with locally advanced oral cancer. Between February 2009 and October 2019, 42 oral cancer patients aged ≥75 years were treated with this therapy. Median age was 80 years (range 75-90 years) and the median follow-up duration was 39 months (range 2-106 months). Of the 42 patients, 34 (81%) were diagnosed with stage IV cancer. The 3-year overall survival, local control, progression-free survival, and disease-specific survival rates were 56%, 69%, 32%, and 67%, respectively. Regarding acute toxicities, grade 3 neutropenia was observed in six patients (14%), anaemia in five (12%), acute kidney injury in one (2%), and oral mucositis in 18 (42%). Late toxicities of grade 3 were observed in seven patients: dysphagia in six (14%) and osteonecrosis of the jaw in one (2%). This study showed that proton beam therapy combined with retrograde intra-arterial infusion chemotherapy was effective for elderly patients with oral cancer, and toxicities were tolerable and manageable. The study findings suggest that this therapy is a potential treatment option for elderly oral cancer patients with difficulty in surgery and systemic chemotherapy.

Feasibility of laparoscopic-assisted transanal pelvic exenteration in locally advanced rectal cancer with anterior invasion.

BACKGROUND: Transanal (Ta) pelvic exenteration is a promising, minimally invasive method for treating locally advanced colorectal cancer. However, since it is technically difficult to perform, Ta pelvic exenteration is rarely reported in locally advanced T4 rectal cancer cases. The aim of this study was to evaluate the feasibility of transabdominal laparoscopy-assisted Ta pelvic exenteration. METHODS: Six patients (4 males and 2 females) had laparoscopy-assisted Ta total or posterior pelvic exenteration for locally advanced or recurrent colorectal cancer cases at the Nagasaki University Hospital between September 2018 and August 2019. Clinical and pathological outcomes were measured and analyzed. RESULTS: The median operation time and intraoperative blood loss were 481 (range 456-709) minutes and 352.5 (range 257-1660) ml, respectively. R0 resection was achieved in all cases, and no patient required open surgery. Two patients had grade 3 complications (Clavien-Dindo) or higher. There was no mortality, and no reoperation was required. CONCLUSIONS: The results suggest that laparoscopic-assisted Ta pelvic exenteration is an acceptable procedure, may help overcome the current technical difficulties, and may improve outcomes in patients with locally advanced rectal cancer.

Prognostic impact of residual lateral lymph node metastasis after neoadjuvant (chemo)radiotherapy in patients with advanced low rectal cancer.

Background: There is a lack of large studies focusing on the prognostic significance of lateral lymph node (LLN) metastasis following LLN dissection (LLND) in rectal cancer. The aim of this study was to evaluate the prognostic impact of LLN metastases on survival of patients with advanced low rectal cancer. Methods: Consecutive patients with locally advanced, but not metastatic, extraperitoneal rectal cancer treated with neoadjuvant (chemo)radiotherapy plus total mesorectal excision between 2004 and 2015 were included in the study. LLND was performed when pretreatment imaging documented enlarged LLNs (7 mm or greater in size). Localization of nodal metastases and long-term outcomes were analysed. Kaplan-Meier analysis was used to compare the survival of patients with ypN0 disease with that of patients with mesorectal ypN+/LLN- status and patients with positive LLNs. The Cox proportional hazards model was used to evaluate predictors of disease-free survival (DFS) and local recurrence. Results: A total of 613 patients were included in the study; LLND was performed in 212 patients (34·6 per cent) and 57 (9·3 per cent) had LLN metastasis. Patients with LLN metastasis had improved DFS and local recurrence cumulative incidence rates compared with patients with mesorectal ypN2+/LLN- disease (DFS: P = 0·014; local recurrence: P = 0·006). Although the DFS rate of patients with LLN metastasis was worse than that of patients with ypN0 disease (P < 0·001), the cumulative incidence of local recurrence was similar (P = 0·491). In multivariable analysis, residual LLN metastasis was not an independent predictor of worse DFS or local recurrence. Conclusion: LLN metastasis is not an independent predictor of local recurrence or survival. Survival of patients presenting with LLN metastasis after (chemo)radiotherapy was intermediate between that of patients with ypN0 status and those with mesorectal ypN2 positivity.

Antecedentes: No existen en la literatura grandes estudios dirigidos a investigar la importancia pronóstica de las metástasis en los ganglios linfáticos laterales (lateral lymph nodes, LLN) después de la disección de los mismos (LLN dissection, LLND) en pacientes con cáncer de recto. El objetivo de este estudio fue evaluar el impacto pronóstico de las metástasis en los LLN sobre la supervivencia de los pacientes con cáncer de recto. Métodos: Se analizaron 613 pacientes consecutivos con cáncer de recto localmente avanzado extraperitoneal y no metastásico tratados con (quimio)radioterapia neoadyuvante seguida de resección total del mesorrecto (total mesorectal excision, TME) entre 2004 y 2015. Se realizó una LLND cuando el estudio mediante pruebas de imagen previo el tratamiento mostró LLN aumentados de tamaño ≥ 7 mm. Se analizó la localización de las metástasis ganglionares y los resultados a largo plazo. El análisis de supervivencia se realizó mediante el método de Kaplan­Meier para comparar las supervivencias de los pacientes ypN0 frente a los pacientes ypN con positividad mesorrectal/LLN negativos y frente a los pacientes LLN positivos. Se utilizó el modelo de riesgo proporcional de Cox para evaluar los factores predictivos de supervivencia libre de enfermedad y de recidiva local. Resultados: Se realizó una LLND en 212 (34,6%) pacientes, y 57 (9,3%) pacientes presentaban metástasis en los LLN. Los pacientes con metástasis en los LLN presentaron mejores curvas de incidencia acumulada de recidiva local y de supervivencia libre de enfermedad en comparación con los pacientes con ganglios mesorrectales ypN2 positivos/LLN negativos (respectivamente, P = 0,0135 y P = 0,0060). Aunque la curva de la supervivencia libre de enfermedad de los pacientes con metástasis en los LLN fue peor que la de los pacientes ypN0 (P < 0,0001), la incidencia acumulada de recidiva local fue similar (P = 0,4905). En el análisis multivariable, la metástasis residual en los LLN no fue un factor predictivo independiente de peor supervivencia libre de enfermedad ni de recidiva local. Conclusión: Las metástasis en los LLN no es un factor predictivo independiente de recidiva local o supervivencia. Los pacientes que presentaron metástasis en los LLN después de (quimio)radioterapia mostraron características de supervivencia intermedias entre ypN0 y pacientes con ganglios mesorrectales ypN2 positivos.

High-Convexity Tightness Predicts the Shunt Response in Idiopathic Normal Pressure Hydrocephalus.

BACKGROUND AND PURPOSE: Although neuroimaging plays an important role in the diagnosis of idiopathic normal pressure hydrocephalus, its predictive value for response to shunt surgery has not been established. The purpose of the current study was to identify neuroimaging markers that predict the shunt response of idiopathic normal pressure hydrocephalus. MATERIALS AND METHODS: Sixty patients with idiopathic normal pressure hydrocephalus underwent presurgical brain MR imaging and clinical evaluation before and 1 year after shunt surgery. The assessed MR imaging features included the Evans index, high-convexity tightness, Sylvian fissure dilation, callosal angle, focal enlargement of the cortical sulci, bumps in the lateral ventricular roof, and deep white matter and periventricular hyperintensities. The idiopathic normal pressure hydrocephalus grading scale total score was used as a primary clinical outcome measure. We used measures for individual symptoms (ie, the idiopathic normal pressure hydrocephalus grading scale subdomain scores, such as gait, cognitive, and urinary scores), the Timed Up and Go test, and the Mini-Mental State Examination as secondary clinical outcome measures. The relationships between presurgical neuroimaging features and postoperative clinical changes were investigated by using simple linear regression analysis. To identify the set of presurgical MR imaging features that best predict surgical outcomes, we performed multiple linear regression analysis by using a bidirectional stepwise method. RESULTS: Simple linear regression analyses demonstrated that presurgical high-convexity tightness, callosal angle, and Sylvian fissure dilation were significantly associated with the 1-year changes in the clinical symptoms. A multiple linear regression analysis demonstrated that presurgical high-convexity tightness alone predicted the improvement of the clinical symptoms 1 year after surgery. CONCLUSIONS: High-convexity tightness is a neuroimaging feature predictive of shunt response in idiopathic normal pressure hydrocephalus.

Correlation of [RuCl3(dppb)(VPy)] cytotoxicity with its effects on the cell membranes: an investigation using Langmuir monolayers as membrane models.

One of the major challenges in drug design is to identify compounds with potential toxicity toward target cells, preferably with molecular-level understanding of their mode of action. In this study, the antitumor property of a ruthenium complex, mer-[RuCl3(dppb)(VPy)] (dppb = 1,4-bis(diphenylphosphine)butane and VPy = 4-vinylpyridine) (RuVPy), was analyzed. Results showed that this compound led to a mortality rate of 50% of HEp-2 cell with 120 ± 10 µmol L(-1), indicating its high toxicity. Then, to prove if its mode of action is associated with its interaction with cell membranes, Langmuir monolayers were used as a membrane model. RuVPy had a strong effect on the surface pressure isotherms, especially on the elastic properties of both the zwitterionic dipalmitoylphosphatidylcholine (DPPC) and the negatively charged dipalmitoylphosphatidylglycerol (DPPG) phospholipids. These data were confirmed by polarization-modulated infrared reflection-absorption spectroscopy (PM-IRRAS). In addition, interactions between the positive group from RuVPy and the phosphate group from the phospholipids were corroborated by density functional theory (DFT) calculations, allowing the determination of the Ru complex orientation at the air-water interface. Although possible contributions from receptors or other cell components cannot be discarded, the results reported here represent evidence for significant effects on the cell membranes which are probably associated with the high toxicity of RuVPy.

Measurement and analysis of internal stress distributions created in gelatin simulated-brain tissue by a pulsed laser-induced liquid jet.

Transsphenoidal surgery is currently employed to treat complex lesions beyond the sella turcica; however, the procedure can be limited by difficulties encountered in dealing with small blood vessels, deep and narrow working spaces, and awkward working angles. To overcome these problems, we have developed a pulsed laser-induced liquid jet system that can dissect tumor tissue while preserving fine blood vessels within deep and narrow working spaces. We have previously evaluated the utility and safety of this procedure. However, the effects of the pulsejet after being injected into the brain are not yet well understood. Especially, the behavior of the stress distribution created by the jet is important because it has recently been reported that high acoustic pressures can affect the brain. In this study, we measured internal stress distributions in a gelatin simulated-brain using photoelasticity experiments. We used a high-speed camera with an image sensor on which an array of micropolarizers was attached to measure the stresses and the shear wave created when the pulsejet enters the simulated brain.

Analysis of liquid reservoir effect induced by pulsed laser liquid jet.

A pulsed-laser-induced liquid jet (LILJ) is a new device used in neurosurgery to simultaneously crush, incise, and aspirate tissues and tumors, preserving blood vessels and nerves. In addition, a feature of a pulsed LILJ is its ability to excavate tissue at constant depth while a liquid jet is being repeatedly focused at the same point. To clarify the mechanisms of constant depth of excavation, we employed a gelatin phantom and extracted brain tissue using a high-speed camera, and we then confirmed that the liquid-reservoir-induced LILJ played an important role in enabling the safe usage of an LILJ.

International models of investigator-initiated trials: implications for Japan.

BACKGROUND: Academic/institutional investigator-initiated clinical trials benefit individuals and society by supplementing gaps in industry-sponsored clinical trials. MATERIALS: In May 2010, experts from Japan, the Republic of Korea, the UK, and the United States, met at a symposium in Tokyo, Japan, to discuss how policies related to the conduct of clinical trials, which have been shown to be effective, may be applied to other regions of the world. RESULTS: In order to increase the availability of anticancer drugs world-wide, nations including Japan should examine the benefits of increasing the number of investigator-initiated clinical trials. These trials represent one of the most effective ways to translate basic scientific knowledge into clinical practice. These trials should be conducted under GCP guidelines and include Investigational New Drug application submissions with the ultimate goal of future drug approval. CONCLUSIONS: To maximize the effectiveness of these trials, a policy to educate health care professionals, cancer patients and their families, and the public in general on the benefits of clinical trials should be strengthened. Finally, policies that expedite the clinical development of novel cancer drugs which have already been shown to be effective in other countries are needed in many nations including Japan to accelerate drug approval.

Bactericidal activity and oral pathogen inactivation by electromagnetic wave irradiation.

AIMS: The aim of this work was to clarify the effects of electromagnetic wave irradiation (EMWI) on oral bacterial pathogens. METHODS AND RESULTS: A Gram-negative (Porphyromonas gingivalis) or Gram-positive (Streptococcus mutans, S. intermedius, Enterococcus faecalis) bacterial suspension was irradiated by EMW apparatus (500-1000 kHz, 5-15 times, 1 s time(-1) ). Quantification of survival bacteria by CFU counting revealed that EMWI exhibited marked bactericidal activity against all tested bacteria and bactericidal activity at 500 kHz increased in an irradiation number-dependent manner. After EMWI at 500 kHz, scanning electron microscopic observations showed that the chain of S. mutans cells was shortened after 5 irradiations and the outlines of bacterial cells (S. mutans and P. gingivalis) were unclear after 5-10 irradiations. EMWI inhibited the inductive effect of S. mutans on pro-inflammatory cytokine production in human monocytes and this inhibitory effect was comparable with that of heat-killed bacteria. Furthermore, using an enzyme activity assay, EMWI partially inactivated the activities of gingipains from P. gingivalis. CONCLUSIONS: These findings demonstrated that EMWI has inactivation and bactericidal activities against single microbial species among four kinds of oral pathogens. SIGNIFICANCE AND IMPACT OF THE STUDY: Electromagnetic wave irradiation may be applicable for medical disinfection and sterilization, such as refractory periapical periodontitis.

Preoperative evaluation of the deep cerebral veins using 3-tesla magnetic resonance imaging.

BACKGROUND: Surgical treatment of deep-seated tumors such as supratentorial intraventricular and thalamic-pineal-tectal region tumors carries a risk of postoperative deficits due to possible damage to deep cerebral veins including the internal cerebral vein. It is often difficult to identify whether the vessel encountered during surgery needs to be preserved or not through the small operative field. Therefore, preoperative evaluation of deep venous structures is important. We evaluated the usefulness of 3-Tesla magnetic resonance imaging (3 T MRI) for this purpose. METHODS: First, the ability to detect deep venous structures was compared with both 3-dimensional computed tomographical angiography (3D-CTA) and 3 T MRI in patients without any damage to deep venous structures. Images of 7 consecutive patients suffering from insulo-opercular gliomas who underwent both imaging modes for the identification of lateral striate arteries were reconstructed for evaluation of the deep cerebral veins. Subsequently, surgery for tumors at the supratentorial intraventricular and thalamic-pineal-tectal regions was prospectively performed with preoperative evaluation of deep venous system only using 3 T MRI. RESULTS: Information on the deep venous systems acquired by 3 T MRI was as useful as that acquired by 3D-CTA. Until today, we have treated 8 cases of supratentorial intraventricular and thalamic-pineal-tectal region tumors with preoperative evaluation of the deep venous system using 3 T MRI without any morbidity. CONCLUSION: Information on the deep venous system obtained with 3 T MRI aids the surgery of supratentorial intraventricular and thalamic-pineal-tectal region tumors. As the required sequences of 3 T MRI are same as those necessary for the neuronavigation system, and 3 T MRI can be achieved without the use of iodine-based contrast agents, 3 T MRI can be an alternative for preoperative evaluation of the deep venous systems.

Clinicopathological study of prognostic factors in patients with pituitary adenomas and Ki-67 labeling index of more than 3%.

BACKGROUND: Pituitary adenoma is generally indolent, but an aggressive subtype including atypical adenoma has uncertain prognosis, and an unclear relationship between prognosis and morphology. AIM: To investigate the prognostic factors of adenomas with Ki-67 labeling index of more than 3%. SUBJECTS AND METHODS: Patients with surgically treated pituitary adenomas with Ki-67 labeling index of more than 3% were retrospectively identified as 13 males and 20 females aged from 15 to 73 yr (mean 47.2 yr) among 527 patients with pituitary adenoma treated at the Department of Neurosurgery, Tohoku University and Department of Neurosurgery, Kohnan Hospital between January 2001 and December 2007. RESULTS: The tumors included 12 cases of gross totally removed pituitary adenomas, and 21 non-totally removed adenomas. Statistical analysis found significant differences in recurrence between gross total and non-total removal (log-rank test, p<0.001), and giant adenomas had higher risk of recurrence or re-growth (log-rank test, p<0.01); 71.4% of re-growth was detected within 12 months if the patients had tumor remnants after the operation. Both immunohistochemical types of tumor and invasion of the surrounding tissue had no statistical correlation with tumor regrowth, and high Ki-67 and p53 labeling index had no relationship with duration of stable disease among these patients independently. CONCLUSIONS: Gross total removal is the most important prognostic factor in patients with adenoma with Ki-67 labeling index of more than 3%. In contrast, giant adenoma carries higher risk of recurrence and/or re-growth. If gross total removal is not achieved immediate adjuvant therapy should be performed.

A case of masticatory disturbance incidental to trigeminal schwannoma: changes in occlusal force and masticatory sensation before and after radiosurgery.

We report here a case of masticatory disturbance evoked by trigeminal schwannoma, in which we have evaluated the changes in occlusal force and masticatory sensation before and after treatment for the tumour. The patient was a 43-year-old woman and her chief complaint was a loss of masticatory sensation on her left side. MR imaging revealed an enhanced tumour in the left cavernous sinus/Meckel's cave. The left masseter muscle function and occlusal force showed remarkable decreases before treatment; however, the sensory thresholds of her facial skin and dental pulp were not significantly different from the control side, indicating that her loss of masticatory sensation was not due to sensory disturbance but to occlusal force weakness. Gamma-knife radiosurgery resulted in a significant improvement in masticatory sensation following an increase in occlusal force.

Pulsed laser-induced liquid jet microcatheter system for rapid and reliable fibrinolysis in acute cerebral embolisms: experiments on safety and preliminary application in porcine cranial vessels.

OBJECTIVE: The authors have incorporated a holmium: YAG laser-induced liquid jet (LILJ) within a microcatheter for rapid, safe, and reliable fibrinolysis, and reported its effectiveness in vitro. The purpose of this study is to evaluate an appropriate operation mode to minimize debris size and to apply the system in in vivo experiments using a porcine cranial artery model. MATERIALS: Evaluation of debris size: The relationships between laser energy and the size of the debris have been evaluated in in vitro experiments. Pulsed LILJ (3 Hz for 60 seconds) were applied to the artificial thrombi (made out of human blood taken from healthy volunteers) in a teflon tube (internal diameter: 4 mm) in the following operation modes: firstly, the laser energy was set at 0.6, 0.8, 1.0, 1.2, 1.4 W, and urokinase (UK) solution (12000 IU/mL) was supplied at rate of 40 mL/hour. In the 0.8 W operation, the concentrations of UK were changed between 0, 1200, 6000, and 12000 lU/mL. Immediately after application of LILJ, the remnant debris were collected and fixed with formaldehyde, and the size and numbers of debris were evaluated under a light microscope. Application in a porcine cranial artery model: The acute embolic models were made using four pigs: the artificial thrombi were made of porcine blood and 1 mL of embolus was used to occlude the left lingual artery via a catheter. After occlusion of lingual artery for 30 minutes, the LILJ microcatheter system was brought to the occlusion site via a guiding catheter and with the assistance of guide-wire. After every 2.5 minutes application of LILJ, angiographies were performed to evaluate the recanalization of the occluded vessels. Cold UK (1200 IU/mL) solution (4 degrees C) was supplied at the rate of 40 mL/hour with laser operation (2 pigs) and without laser operation (2 pigs: control). The pigs were decapitated, and vessels at the laser irradiation sites were obtained to evaluate the damage to the vessel wall. RESULTS: Evaluation of debris size: After application of UK solution by the LILJ (12000 lU/mL), 48.7 (1.0 W) to 72.0% (0.8 W) of debris were under 200 microm in size, while 3.7 (0.8 W) to 17.0% (1.2 W) of them exceeded 600 microm, and the 0.8 W operation mode had a tendency to be the better operation mode. During the 0.8 W operation mode, 58 (without UK) to 72% (12000 lU/mi) of debris were under 200 microm in size, while 3.5 (12000 lU/mL) to 8.5% (without UK) of them exceeded 600 microm. Application in a porcine cranial artery model: Recanalization of the occluded vessels was obtained at 15 and 20 minutes in the treatment group. Histological specimens showed neither apparent mechanical nor thermal damage. CONCLUSION: Although an additional system to collect debris, which cannot be dealt with in the pharmacological effect of fibrinolytics in the short-term, should be developed, the present results show the possibility of the LILJ microcatheter system to become a useful assistant device for the mechanical fragmentation of embolus and the enhancement of fibrinolytics.

Primary CNS lymphoma treated with combined intra-arterial ACNU and radiotherapy.

OBJECT: To assess whether nimustine (ACNU), a drug that can cross the blood brain barrier, combined with radiotherapy, improved the survival of patients with primary central nervous system lymphoma (PCNSL). CLINICAL MATERIALS AND METHODS: Between 1995 and 2005, we treated 63 immunocompetent PCNSL patients with combination therapy consisting of intra-arterial ACNU (100 mg/m(2)) and whole brain radiotherapy (36-50 Gy). Their median age was 60 years (range 28-81). The median follow-up was 24 months. FINDINGS: With this regimen we achieved a complete response rate of 75% (43 of 57 patients). Kaplan-Meier estimates for median progression-free survival and median overall survival were 26 and 39 months, respectively. The 3- and 5-year survival rates were 51% (95% confidence interval [CI], 36-65%) and 32% (95% CI, 17-47%), respectively. By multivariate analysis, age (<60 vs. > or =60 years) was the only statistically significant prognostic factor; the WBRT dose, sex, and number of tumors were not significant prognostic factors in this study. Myelosuppression was the most frequent side effect, 60% of patients experienced grade 3-4 leukopenia. Late neurotoxicity as a result of treatment was observed in 14 of 43 patients (34%) and higher age (>60) was associated with a high risk of neurotoxicity. CONCLUSION: The intra-arterial administration of ACNU combined with radiation therapy yielded a high response rate at acceptable toxicity levels in younger patients with PCNSL. However, late neurotoxicity was a serious complication in patients above 60 years of age.

Development of shock wave assisted therapeutic devices and establishment of shock wave therapy.

In order to exploit systems for shock wave therapy, we are working for the development of clinical devices that are based on the concept of shock waves or related phenomena. The paper describes these new therapeutic devices designed for the minimally invasive approach to vascular thromboloysis, selective dissection of tissues, and drug or DNA delivery. To investigate the response of cells to shock loading, a precise method of shock waves generation in space and time has been developed. This method has been studied for application in cardiovascular therapy, cancer treatment, and cranioplasty in close vicinity of the brain. A laser ablation shock wave assisted particle acceleration device has been developed for delivering drug and DNA into soft targets in the human body. The penetration depth of microparticles observed in the experimental targets is believed to be sufficient for pharmacological treatments. In order to achieve an efficient method for rapid revascularization of cerebral thrombosis, a laser induced liquid jet (LILJ) system has been developed. The LILJ has been successfully applied for selective dissection of soft tissue preserving nerve and blood vessels. The system has been further improved by using piezoelectric actuators to drive the liquid jets, as an alternative to pulse laser.

Malignant transformation of pleomorphic xanthoastrocytoma.

A 31-year-old woman presented with a pleomorphic xantho-astrocytoma (PXA) manifesting as epilepsy. The tumour was partially resected. Histological examination revealed cellular pleomorphism and cytoplasmic vacuolation consistent with PXA, but no mitoses, necrosis, or endothelial proliferation. Follow-up neuro-imaging showed the residual tumour had grown rapidly with dissemination in the spinal cord. The recurrent lesion was totally resected and was shown to be glioblastoma. The patient has survived without signs of recurrence for 36 months after adjuvant radiochemotherapy. The biological behaviour of PXA cannot be predicted based on the histological features and careful follow up is essential.

Stereotactic radiosurgery followed by whole ventricular irradiation for primary intracranial germinoma of the pineal region.

Intracranial germinomas can be cured by radiotherapy and/or chemotherapy. Three patients with pineal germinoma were treated with stereotactic radiosurgery using the gamma knife (10 - 12 Gy) to the tumors followed by whole ventricular irradiation (24 Gy). All patients had solitary pineal tumor measuring less than 3 cm, clinically compatible with germinoma, normal cerebrospinal fluid (CSF) and serum levels of alpha-fetoprotein and beta-human chorionic gonadotropin, no disseminated disease on spinal magnetic resonance (MR) imaging, and no abnormal CSF cytology. All patients showed complete response to the combined radiotherapy, and MR imaging has shown no recurrence of the tumor. Combined radiotherapy using gamma knife radiosurgery is effective for pineal germinoma, and reduced the cost of treatment with less need for hospitalization.