• Radiation Oncology Journal
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• v.26 no.4
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• pp.213-221
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• 2008

Purpose: The objective of this retrospective study was to identify predictive factors for the complete pathologic response and tumor downstaging after preoperative concurrent chemoradiotherapy for locally advanced rectal cancer. Materials and Methods: Between the years 2000 and 2008, 39 patients with newly diagnosed rectal cancer without prior evidence of distant metastasis received preoperative concurrent chemoradiotherapy followed by surgery. The median radiation dose was 50.4 Gy (range, $45{\sim}59.4\;Gy$)). Thirty-eight patients received concurrent infusional 5-fluorouracil and leucovorin, while one patient received oral capecitabine twice daily during radiotherapy. Results: A complete pathologic response (CR) was demonstrated in 12 of 39 patients (31%), while T-downstaging was observed in 24 of 39 patients (63%). N-downstaging was observed in 18 of 28 patients (64%), with a positive node in the CT scan or ultrasound. Two patients with clinical negative nodes were observed in surgical specimens. The results from a univariate analysis indicated that the tumor circumferential extent was less than 50% (p=0.031). Moreover, the length of the tumor was less than 5 cm (p=0.004), while the post-treatment carcinoembryonic antigen (CEA) levels were less than or equal to 3.0 ng/mL (p=0.015) and were significantly associated with high pathologic CR rates. The univariate analysis also indicated that the adenocarcinoma (p=0.045) and radiation dose greater than or equal to 50 Gy (p=0.021) were significantly associated with high T-downstaging, while a radiotherapy duration of less than or equal to 42 days (p=0.018) was significantly associated with N-downstaging. The results from the multivariate analysis indicated that the lesser circumferential extent of the tumor (hazard ratio [HR] 0.150; p=0.028) and shorter tumor length (HR, 0.084; p=0.005) independently predicted a higher pathologic CR. The multivariate analysis also indicated that a higher radiation dose was significantly associated with higher T-downstaging (HR, 0.115; p=0.025), while the shorter duration of radiotherapy was significantly associated with higher N-downstaging (HR, 0.028; p=0.010). Conclusion: The circumferential extent of the tumor and its length was a predictor for the pathologic CR, while radiation dose and duration of radiotherapy were predictors for tumor downstaging. Hence, these factors may be used to predict outcomes for patients and to develop further treatment guidelines for high-risk patients.

• The Journal of the Korean bone and joint tumor society
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• v.12 no.2
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• pp.126-130
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• 2006

Liposclerosing myxofibrous tumor (LSMFT) is a fibro-osseous lesion of the bone with a marked predilection for the intertrochanteric region of the proximal femur. It is characterized by a complex mixture of histological elements including fibrous dysplasia-like features, myxofibrous tissue, lipomatous area, ischemic ossification, xanthoma cells and pseudo-Paget's bone. Though some consider LSMFT as a variant of the fibrous dysplasia, intraosseous lipoma, or other benign osseous lesions, recently LSMFT is emerged as a genuine clinicopathologic entity. We experienced a 48-year female patient with typical histologic and radiologic findings of LSMFT. It was located at the intertrochanteric area of the femur. Radiologically, the lesion was radiolucent and ground-glass appearance with sclerotic rim in the plain film and magnetic resonance imaging. Histologically, myxofibrous tissue, lipomatous area and fibrous dysplasia-like features were predominant findings.

• Journal of the Korean Society of Radiology
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• v.15 no.6
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• pp.849-853
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• 2021

PET images used in medical diagnoses are created using positron emitting radionuclides. The radiation used for imaging is generated at 0.511 MeV by p-annihilation. The CSDA range is the distance the particle radiation flew physically, and it is different from the range shown in PET images. This study proposes a novel method that uses radiological criteria to measure this range. The experiment was conducted by applying the MCNP6 simulation to positron emitting nuclides ¹⁸F, ¹¹C, ¹³N, and ¹⁵O. Radiological criteria were based on the location of the p-annihilation event, which is also the image signal. Results showed the radiological range of positrons to be 2.3, 3.9, 5.0, and 7.9 mm for ¹⁸F, ¹¹C, ¹³N, and ¹⁵O, respectively. The higher the positron energy, the larger its difference from the CSDA range. Positron emitting nuclide is being developed and studied as a nuclide for dosimetry or radiotherapy. Further research needs to be conducted into various positron ranges.

• Clinics in Shoulder and Elbow
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• v.12 no.1
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• pp.1-6
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• 2009

Purpose: To evaluate and report the clinical and radiological outcomes of open reduction and internal fixation with a mini-T plate for unstable distal clavicle fractures. Materials and Methods: From December 2004 to July 2007, fifteen patients who had a fracture of the distal clavicle (Neer type II fracture) were treated with an open reduction and internal fixation using a mini-T plate. They were followed up for a minimum of one year and the clinical and radiological results were analyzed. Results: The average time to fracture union was 3.1(3~4) months. There were no complications, such as deep infection or fixation loss. The mean ASES score was 97 points (85~100points) at the last follow up period, and 14 patients had a full range of motion of the shoulder. Conclusion: Open reduction and internal fixation with a mini-T plate for unstable distal clavicle fracture is a good surgical method with good clinical and radiological results.

• Radiation Oncology Journal
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• v.19 no.2
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• pp.199-204
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• 2001

Purpoe : To find the optimal values of total arc degree to protect the normal brain tissue from high dose radiation in stereotactic radiotherapy planning. Methods and Materials : With Xknife-3 planning system & 4 MV linear accelerator, the authors planned under various values of parameters. One isocenter, 12, 20, 30, 40, 50, and 60 mm of collimator diameters, $100^{\circ},\;200^{\circ},\;300^{\circ},\;400^{\circ}C,\;500^{\circ},\;600^{\circ}$ or total arc degrees, and $30^{\circ}\;or\;45^{\circ}$ or arc intervals were used. After the completion of planning, the plans were compared each other using $V_{50}$ (the volume of normal brain that is delivered high dose radiation) and integral biologically effective dose. Results : At $30^{\circ}$ of arc interval, the values of $V_{50}$ had the decreased pattern with the increase of total arc degree in any collimator diameter. At 45 arc interval, up to $400^{\circ}$ of total arc degree, the values of $ V_{50}$ decreased with the increase of total arc degree, but at $500^{\circ}\;and\;600^{\circ}$ of total arc degrees, the values increased. At $30^{\circ}$ of arc interval, integral biologically effective dose showed the decreased pattern with the increase of total arc degree in any collimator diameter. At $45^{\circ}$ arc interval with less than 40 mm collimator diameter, the integral biologically effective dose decreased with the increase of total arc degree, but with n and n mm or collimator diameters, up to $400^{\circ}$ or total arc degree, integral biologically effective dose decreased with the increase of total arc degree, but at $500^{\circ}\;and\;600^{\circ}$ of total arc degrees, the values increased. Conclusion : In the stereotactic radiotherapy planning for brain lesions, planning with $400^{\circ}$ of total arc degree is optimal. Especially, when the larger collimator more than 50 mm diameter should be used, the uses of $500^{\circ}\;and\;600^{\circ}$ of total arc degrees make the increase of$V_{50}$ and integral biologically effective dose. Therefore stereotactic radiotherapy planning using $400^{\circ}$ of total arc degree can increase the therapeutic ratio and produce the effective outcome in the management of personal and mechanical sources in radiotherapy department.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 1999.07a
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• pp.47-55
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• 1999

고온온열치료는 radiofrequency, ultrasound , microwave, 원적외선 등을 이용하여 신체의 부분 혹은 전신을 4$0^{\circ}C$ 이상으로 가열하여 암을 치료하는 방법이다. 우리나라에 도 입된 15기의 기계중 현재까지 사용되고 있는 것은 대부분이 radiofrequency를 사용하는 기 계이며 현재 고신의대, 동아의대, 부산메리놀병원, 여의도 성모병원, 영남의대, 전주예수병원 등에서 환자치료에 사용하고 있다. 고온 온열치료제(hyperthermia)는 직접 암세포를 죽이는 작용, 방사선치료나 항암제치료와 병행하여 그 효과를 증강시키는 작용으로 크게 나눌수 있 다. 직접 암세포를 죽이기 위하여는 43$^{\circ}C$이상의 고온을 사용하여야 하나 인체에서는 42.5$^{\circ}C$ 이상으로 가온하기가 쉽지않아 4$0^{\circ}C$~42$^{\circ}C$ 정도의 온도에서 방사선 치료나 항암제 치료효과 를 증진시키는 작용을 임상에서 주로 사용하고 있다. 특히 방사선 치료와 병합 사용시 그 효과가 뛰어나 간암, 난소암, 대장 직장암, 식도암, 위암, 자궁암, 전립선안, 췌장암, 폐암등, 거의 모든 암에서 부작용을 증가시키지 않으면서 그 효율을 1.1-6.14배나 증가시킨다고 보 고되고 있어 지난 10여 년간 제자리걸음을 하고 있는 암의 치료에 희망을 주고 있다. 방사 선 치료와 병합시 효과를 증대시키는 기전은 1)세포의 핵 합성기 (S-phase)는 방사선 치료 에는 매우 저항력이 강하여 잘 죽지 않으나 고온온열치료에는 예민함으로 암세포는 정상조 직에 비해 산소가 부족하여 염기성대사(anaerobic metabolism)를 많이 함으로 그 부산물인 유산 (lactic acid)이 많이 생성됨으로 정상조직보다 pH가 낮아 암 조직이 정상조직에 비해 고온온열치료에 더 잘 듣는 원인이 된다. 3) 영양이 부족한 상태의 세포는 고온온열치료에 훨씬 예민하다. 4) 암조직은 혈관상태가 정상조직에 비해 좋지 않음으로 정상조직보다 쉽게 가온이 되며, 일단 가온된 온도는 잘 식지 않음으로 정상조직에 비해 훨씬 효율적이다. 5)고 온온열치료는 4$0^{\circ}C$~43.5 $^{\circ}C$정도에서만 이 작용이 일어남으로 정상인체에서 43$^{\circ}C$이상의 가온 은 쉽지 않음으로 이 효과는 암조직에서 주고 일어나게 된다. 6)고온온열치료는 방사선치료 후에 생기는 손상의 재생을 억제함으로 방사선의 치료효과를 높인다. 7)38.5$^{\circ}C$~41.5$^{\circ}C$의 낮 은 온도에서도 암조직의 산소 상태를 호전시켜 방사선 치료효과를 증대시키는 역할을 한다.

• Tuberculosis and Respiratory Diseases
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• v.47 no.4
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• pp.498-506
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• 1999

Background : The causes of solitary pulmonary nodule are many, but the main concern is whether the nodule is benign or malignant. Because a solitary pulmonary nodule is the initial manifestation of the majority of lung cancer, accurate clinical and radiologic interpretation is important. Bayes' theorem is a simple method of combining clinical and radiologic findings to estimate the probability that a nodule in an individual patients is malignant. We estimated the probability of malignancy of solitary pulmonary nodules with a specific combination of features by Bayesian approach. Method : One hundred and eighty patients with solitary pulmonary nodules were identified from multi-center analysis. The hospital records of these patients were reviewed and patient age, smoking history, original radiologic findings, and diagnosis of the solitary pulmonary nodules were recorded. The diagnosis of solitary pulmonary nodule was established pathologically in all patients. We used to Bayes' theorem to devise a simple scheme for estimating the likelihood that a solitary pulmonary nodule is malignant based on radiological and clinical characteristics. Results : In patients characteristics, the probability of malignancy increases with advancing age, peaking in patients older than 66 year of age(LR : 3.64), and higher in patients with smoking history more than 46 pack years(LR : 8.38). In radiological features, the likelihood ratios were increased with increasing size of the nodule and nodule with lobulated or spiculated margin. Conclusion : In conclusion, the likelihood ratios of malignancy may improve the accuracy of the probability of malignancy, and can be a guide of management of solitary pulmonary nodule.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.11 no.1
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• pp.7-22
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• 1981

A morphological and positional classification was undertaken in the transcranial and transorbital views of 174 traceable films which had been selected from those of 274 patients and previous tracing was performed. For the positional analysis, the author adopted the method which is not influenced by TMJ remodelling, and for the morphological classification, made progress the general method by adding indefinite type to four basic types. The aims of this sutudy consists in performing positional and morphological analysis of condylar head and in its morphological and positional variation in symptomatic patients. I want to express my sincere gratitude to Prof. Park, Tae Won in Seoul National University, interesting me in this field researches and for his never failing interests. I would lide to thank Prof. Ahn, Hyung Kyu and Prof. You, Dong Soo for helpful discussion and critical readings. The author is also indebted to Prof. Fuchihate Hajime in Osaka University, Prof. Uemura, Shusaburo and the late Dr. Nishihara, Heihachi for fruitful discussion and encourgements.

• 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.

• Radiation Oncology Journal
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• v.11 no.1
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• pp.69-77
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• 1993

Treatment of cerebellar medulloblastoma has been much improved with modern surgical technique for gross total tumor removal and adequate radiation therapy for the whole craniospinal axis. Questions have been arosen about the optimal radiation dose for the preventive treatment of whole cranium and whole spinal axis. Recently, many authors have reported their treatment results as comparable to older data, using lower than conventional dose of 3,600 cGy-4,000 cGy. For 50 patients treated between 1981 and 1990 at the Department of Radiation Therapy of SNUH, retrospective analysis was done for the treatment result, especially the neuraxis control, by radiation dose for the presymptomatic area of the disease. Analysis only by total spinal dose did not give any significant difference. But further analysis by following patient group; 3,600 cGy/150 cGy (n=6), 3,000 cGy/150 cGy (n=10), 2,400 cGy/150 cGy (n=17) and 2,400 cGy/100-120 cGy (n=11) showed significant improvement of neuraxis control by decreasing order (p =0.003). There was no significant difference in overall survival between the groups. For the 19 patients who had been confirmed initially as having no neuraxis disease, TDF 30 was the cur-off value that could prevent neuraxis failure (p =0.004). We couldn't define any TDF value that give reasonable control for the patient group with positive CSF study at initial diagnosis.