• Radiation Oncology Journal
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• v.20 no.2
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• pp.100-107
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• 2002

Purpose : The aim of this retrospective study was to assess the treatment results of 30 patients with pineal region tumors who were underwent radiation therapy under the diagnosis by either CT or MRI. There was no histological verification. We analyzed the prognostic factors that have a significant effect on the overall survival (OS) and disease free survival (DFS) rates. Materials and Methods : A total 30 patients with pineal region tumors were treated between March 1983 and August 1995. After a trial radiation therapy of $20\~30\;Gy/2\~3$ weeks, the patients were evaluated for their clinical response and radiological response by either CT or MRI and the final treatment direction was then decided. According to their response to the trial radiation therapy and the involved site, radiation treatment was given in various fields i.e., local, ventricle, whole brain and craniospinal field. The radiation dose ranged from 40.8 to 59.4 Gy (Median 50.4 Gy). The median follow up was 36.5 months $(4\~172\;months)$. Results : An improvement or stability in the clinical symptoms was observed in 28 patients $(93.3\%)$ after the trial RT. Nineteen patients $(63.3\%)$ showed a partial or complete response by CT or MRI. The two-year and five-year survival rates of the patients were $66.7\%$ and $55.1\%$, respectively. No significant difference in the survival rates according to the degree of the radiological response was abserved after the trial RT. The results of univariate analysis showed that age, the primary site, the performance status $(KPS\geq70)$, the degree of response after completing RT and the RT field were significant prognostic factors affecting the survival and disease free survival rates (p<0.05). Conclusion : The clinical and histological characteristics of pineal region tumors are quite complex and diverse. Therefore, it is difficult to predict the histological diagnosis and the possibility of radiocurability only with the initial response to RT. We think that the development of less invasive histological diagnostic techniques and tailored treatment to the histological type of each tumor are needed.

• Radiation Oncology Journal
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• v.15 no.3
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• pp.197-206
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• 1997

Purpose : Phospholipase D (PLD) catalyzes the hydrolysis of phosphatidylcholine to phosphatidic acid (PA) and choline. Recently, PLD has been drawing much attentions and considered to be associated with cancer Process since it is involved in cellular signal transduction. In this experiment, oleate-PLD activities were measured in various tissues of the living rats after whole body irradiation. Materials and Methods : The reaction mixture for the PLD assay contained $0.1\;\muCi\;1,2-di[1-^{14}C]palmitoyl$ phosphatidylcholine 0.5mM phosphatidylcholine, 5mM sodium oleate, $0.2\%$ taurodeoxycholate, 50mM HEPES buffer(pH 6.5), 10mM $CaCl_2$, and 25mM KF. phosphatidic acid, the reaction product, was separated by TLC and its radioactivity was measured with a scintillation counter. The whole body irradiation was given to the female Wistar rats via Cobalt 60 Teletherapy with field size of 10cmx loom and an exposure of 2.7Gy per minute to the total doses of 10Gy and 25Gy. Results : Among the tissues examined, PLD activity in lung was the highest one and was followed by kidney, skeletal muscle, brain, spleen, bone marrow, thymus, and liver. Upon irradiation, alteration of PLD activity was observed in thymus, spleen, lung, and bone marrow. Especially PLD activities of the spleen and thymus revealed the highest sensitivity toward $\gamma-rar$ with more than two times amplification in their activities In contrast, the PLD activity of bone marrow appears to be reduced to nearly $30\%$. Irradiation effect was hardly detected in liver which showed the lowest PLD activity. Conclusion : The PLD activities affected most sensitively by the whole-body irradiation seem to be associated with organs involved in immunity and hematopoiesis. This observation s1ron91y indicates that the PLD is closely related to the physiological function of these organs, Furthermore, radiation stress could offer an important means to explore the phenomena covering from cell Proliferation to cell death on these organs.

• Radiation Oncology Journal
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• v.20 no.3
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• pp.193-198
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• 2002

Purpose : Oligodendrogliomas (ODG) are a rare, slow growing, tumor in the brain, which can be cured by complete surgical resection, but as yet it is not known if postoperative adjuvant radiation therapy (RT) is essential, We analyzed the treatment results of patients with irradiated ODG to investigate the efficacy of RT in terms of survival rates and other influencing prognostic factors. Methods and Materials : Between March 1983 and December 1997, 42 patients with ODG were treated with RT at our hospital. The RT was peformed dally at a dose of $1.8\~2.0\;Gy$, at 5 fractions per week, to a total dose of between 39.6 Gy and 64.8 Gy (mean 53.3 Gy). The ages of the patients ranged between 5 and 62 years, with a median age of 39 years. The mean follow-up period was 63.4 months (8-152 months). The Kaplan-Meier method was used to assess the survival, and 5 year survival rates (5-YSR). Log rank tests and Cox regression analyses were used to define the significance of prognostic factors. Results : The majority of ODG in this study were located in the cerebral hemisphere $(83.3\%)$. ODG are slightly more common in men than women, and commonly occurs in middle age, between the 3rd and 4th decades. It has been recommended that RT is commenced within 4 weeks following surgery (5-YSR; $86\%\;vs.\;49\%;\;p<0.03$). Histologically well differentiated, as opposed to poorly differentiated, tumors were found to have a more favorable prognosis (p<0.02). The actuarial 5-YSR was $65.3\%$ (median survival 90 months). 5-YSR for the various extents of surgical excision, followed by external RT, was superior to that of biopsy only followed by external RT $(69.9\%\;vs.\;25.6\%,\;p<0.01)$. Tumor size and location, overall elapsed irradiation days, age, sex, whole brain irradiation as a course of treatment and chemotherapy, had no influence on the 5-YSR (p>0.05). Conclusion : A local involved field irradiation with conventional fractionation, commencing within 4 weeks following surgical excision of the tumor, was beneficial for the 5-YSR, but a total radiation dose exceeding 60 Gy did not improve the 5-YSR.

• 대한방사선치료학회:학술대회논문집
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• 2005.06a
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• pp.23-26
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• 2005

Introduction: To evaluate whether modified MUPIT applicator can effectively eradicate recurrent tumor in uterine cervix cancer and reduce rectal complication after complete radiation treatment. Methods and Materials: Modified MUPIT applicator basically consists of an acrylic cylinder with flexible brain applicator , an acrylic template with a predrilled array of holes that serve as guides for interstitial needles and interstitial needles. CT scan was performed to determine tumor volume and the position of interstitial needles. Modified MUPIT applicator was applied to patient in operation room and the accuracy for position of interstitial needles in tumor volume was confirmed by CTscan. Brachytherapy was delivered using modified MUPIT applicator and RALS (192-Ir HDR) after calculated computer planning by orthogonal film. The daily dose was 600cGy and the total dose was delivered 3000cGy in tumor volume by BID. Rectal dose was measured by TLD at 5 points so that evaluated the risk of rectal complication. Result: The application of modified MUPIT applicator improved dramatically dose distributions in tumor volume and follow-up of 3 month for this patient was clinically partial response without normal tissue complication, Rectal dose was measured 34.1cGy, 57.1cGy, 103.8cGy, 162.7cGy, 165.7cGy at each points, especially the rectal dose including previous EBRT and ICR was 34.1cGy, 57.1cGy Conclusion: Patients with locally recurrent tumor in uterine cervix cancer treated with modified MIUPIT applicator can expect reasonable rates of local control. The advantages of the system are the fixed geometry Provided by the template and cylinders, and improved dose distributions in irregular tumor volume without rectal complication

• Radiation Oncology Journal
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• v.9 no.2
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• pp.177-184
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• 1991

From December 1984 to February 1990, 16 patients with tumors of pineal and suprasellar location were treated with radiation therapy. Tissue diagnoses were obtained before radiation therapy in 5 patients and 11 were irradiated without histologic confirmation. Initial treatments for these patients were craniospinal plus boost primary irradiation(six), whole brain plus boost primary irradiation(nine), primary tumor site irradiation(one). The 5 year actuarial survival rate is $71\%$. Three cases with elevated beta-human chorionic gonadotropin(HCG) responded favorably to radiation, but pineal tumors with elevated alpha-fetoprotein(AFP) did not respond well. Spinal metastasis developed in 2 cases(2/15) with elevated AFP : one received prophylactic spinal irradiation, another did not. Our studies suggest that more aggressive treatment would be necessary in patient with elevated AFP and in this patient, radiation therapy may be initiated without pathologic confirmation. From the result of our study, routine use of prophylactic spinal irrdiation for all patients with pineal region tumor is not indicated and use of prophylactic spinal irradiation is considered for the patients with positive craniospinal fluid cytology, meningeal seeding, disease extension along the ventricular wall and biopsy proven germinoma.

• Journal of Korean Neurosurgical Society
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• v.38 no.3
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• pp.184-189
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• 2005

Objective : Hemangioblastomas are highly vascular and benign neoplasm of the central nervous system[CNS]. They can often be found as multiple lesions, as is commonly observed in von Hippel-Lindau[VHL] disease. The aim of this study is to determine the proper management for multiple hemangioblastomas. Methods : Since 1990, 78cases of hemangioblastoma have been encountered. Among these, 9cases were multiple hemangioblastomas that were treated with surgical resection with or without radiosurgery. The medical, radiological, surgical and histological records were reviewed retrospectively and analyzed statistically. Results : Nine patients presented with multiple hemangioblastomas and were diagnosed as VHL disease. The mean follow-up duration was 75.7months [$6.6{\sim}159.2months$] after the first surgical treatment. Three patients were treated with surgical resection alone and six patients were treated by both surgical resection and radiosurgery. Twenty-one surgical procedures [13 surgical resections and 8 radiosurgery] were performed. One patient required ventriculoperitoneal shunt and a posterior fossa decompressive craniectomy because of post-radiation brain swelling. Another patient refused additional treatment for the newly developed lesions after the successful treatment of initial lesions. The other patient who presented with numerous lesions in the whole brain and spine underwent cranio-spinal irradiation. Remaining patients showed good results. Conclusion : The surgical outcomes for the patients with a single lesion of the CNS hemangioblastoma are favorable. However. the treatment of multiple hemangioblastoma is more difficult, and should be treated by surgical resection and radiosurgery with careful consideration.

• Journal of Korean Neurosurgical Society
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• v.45 no.2
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• pp.107-111
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• 2009

Meningiomas are usually benign neoplasms in which extracranial metastases occur very rarely. We report a case of multiple extracranial metastases of an atypical meningioma following a local recurrence. A 68-year-old man presented with left-side motor weakness and dysarthria for two weeks. A computed tomography (CT) scan and magnetic resonance imaging (MRI) showed an intraventricular tumor. We performed a total mass removal, and the histopathologic findings were consistent with benign meningioma. Eight months later, the meningioma recurred. We performed a reoperation and whole brain radiation therapy postoperatively. The histopathologic findings showed atypical meningioma. Six months later, CT and MRI revealed metastases to multiple vertebrae, lung, ribs and perirenal soft tissue so a decompressive laminectomy with mass removal was performed. The histopathologic findings of the spinal tumors showed atypical meningioma. The results from perirenal biopsies were consistent with metastatic meningioma. In conclusion, extracranial metastasis as well as local recurrence must be considered in atypical or anaplastic meningioma. There must be regular follow-ups. Finally, an evaluation of the chest, abdomen and bone is necessary, especially when related symptoms or signs develop.

• Journal of Radiation Industry
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• v.9 no.3
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• pp.143-151
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• 2015

A PET-MR system is particularly useful in diagnosing brain diseases. We have developed a prototype positron emission tomography (PET) system which can be inserted into the bore of a whole-body magnetic resonance imaging (MRI) system that enables us to obtain PET and MRI images simultaneously with a reduced cost. Silicon photomultipliers (SiPM) are appropriated as a PET detector at PET/MR system because detectors have a high gain and are insensitive to magnetic fields. Despite of its improved performance compared to that of PMT-based detectors, there is a problem of the photo-peak channel shift which is due to the increase of the temperature inside the ring detector. This problem will occur decreasing sensitivity of the PET and image distortion. In this paper, I quantitative analyze parameters of the KAIST SiPM depending on temperature by experiments. And I designed cooling methods in consideration of the degradation of sensors for correction of the temperature in the PET gantry. According to this research, we expect that distortive images and degradation of the sensitivity will not be occurred with using the above idea to reduce heat even if the PET system operates for a long time.

• Journal of Korean Neurosurgical Society
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• v.54 no.5
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• pp.399-404
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• 2013

Objective : The authors conducted a retrospective cohort study to determine prognostic factors and treatment outcomes of brain metastases (BM) from breast cancer (BC) after Gamma Knife radiosurgery (GKS). Methods : Pathologic and clinical features, and outcomes were analyzed in a cohort of 62 patients with BM from BC treated by GKS. The Kaplan- Meier method, the log-rank test, and Cox's proportional hazards model were used to assess prognostic factors. Results : Median survival after GKS was 73.0 weeks (95% confidence interval, 46.0-100.1). HER2+ [hazard ratio (HR) 0.441; p=0.045], Karnofsky performance scale (KPS) ${\geq}70$ (RR 0.416; p=0.050) and systemic chemotherapy after GKS (RR 0.282; p=0.001) were found to be a favorable prognostic factor of overall survival. Actuarial local control (LC) rate were $89.5{\pm}4.5%$ and $70.5{\pm}6.9%$ at 6 and 12 months after GKS, respectively. No prognostic factors were found to affect LC rate. Uni- and multivariate analysis revealed that the distant control (DC) rate was higher in patients with; a small number (${\leq}3$) of metastasis (HR 0.300; p=0.045), no known extracranial metastasis (p=0.013, log-rank test), or the HER2+ subtype (HR 0.267; p=0.027). Additional whole brain radiation therapy and metastasis volume were not found to be significantly associated with LC, DC, or overall survival. Conclusion : The treatment outcomes of patients with newly diagnosed BM from BC treated with GKS could be affected primarily by intrinsic subtype, KPS, and systemic chemotherapy. Therapeutic strategy and prognosis scoring system should be individualized based on considerations of intrinsic subtype in addition to traditionally known parameters related to stereotactic radiosurgery.

• Radiation Oncology Journal
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• v.21 no.3
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• pp.222-226
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• 2003

Purpose: The interaction of the Fas: Fas ligand has been recognized to play an important role in radiation induced apoptosis. The purpose of this study was to investigate the role of Fas and Fas ligand mutations, in radiation-induced apoptosis in vivo. Materials and Methods: Mice with a mutation in the Fas ($C57BL/6J-Fas^{lpr}$) and its normal control (C57BL/6J) and the Fas ligand ($C3H/HeJ-Fas^{gld}$) and its normal control (C3H/HeJ), were used in this study. Eight-week old male mice were given whole body radiation. After irradiation, the mice were killed at various time intervals, and their spleens collected. Tissue sample was stained with hematoxylin-eosin, and the numbers of apoptotic cells scored. The regulating molecules of apoptosis including the p53, Bcl-2, Bax, $Bcl-X_L\;and\;Bcl-X_s$ genes were also analyzed by Western blotting. Results: With 2.5 Gy and 10 Gy of irradiation, the levels of apoptosis were lower in the $C57BL/6J-Fas^{lpr}\;and\;C3H/HeJ-Fas^{gld}$ mice than in the control mice (p<0.05). With the expression of apoptosis regulating molecules, the Bax was increased in both the C57BL/6J and C3H/HeJ mice in response to radiation; the peak levels of Bax in the C57BL6J and C3H/HeJ were 3 and 3.3-fold higher after 8hr, respectively. However the Bax was not increased in either the $C57BL/6J-Fas^{lpr}\;or\;C3H/HeJ-Fas^{gld}$mice. The p53, Bcl-X_L,\;Bcl-X_S$and Bcl-2 showed no significant changes in the $C57BL/6J-Fas^{lpr},\;C3H/HeJ-Fas^{gld}$, C57BL/6J and C3H/HeJ mice. Conclusion: The levels of radiation-induced apoptosis were lower in the lpr and gld, than the control mice, which seemed to be related to the level of Bax activation due to the radiation in the lpr and gld mice. This result suggests that Fas/Fas L plays an important role in radiation-induced apoptosis in vivo.