• Radiation Oncology Journal
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• v.20 no.1
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• pp.41-52
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• 2002

Purpose : 3D conformal radiotherapy, the optimum dose delivered to the tumor and provided the risk of normal tissue unless marginal miss, was restricted by organ motion. For tumors in the thorax and abdomen, the planning target volume (PTV) is decided including the margin for movement of tumor volumes during treatment due to patients breathing. We designed the respiratory gating radiotherapy device (RGRD) for using during CT simulation, dose planning and beam delivery at identical breathing period conditions. Using RGRD, reducing the treatment margin for organ (thorax or abdomen) motion due to breathing and improve dose distribution for 3D conformal radiotherapy. Materials and Methods : The internal organ motion data for lung cancer patients were obtained by examining the diaphragm in the supine position to find the position dependency. We made a respiratory gating radiotherapy device (RGRD) that is composed of a strip band, drug sensor, micro switch, and a connected on-off switch in a LINAC control box. During same breathing period by RGRD, spiral CT scan, virtual simulation, and 3D dose planing for lung cancer patients were peformed, without an extended PTV margin for free breathing, and then the dose was delivered at the same positions. We calculated effective volumes and normal tissue complication probabilities (NTCP) using dose volume histograms for normal lung, and analyzed changes in doses associated with selected NTCP levels and tumor control probabilities (TCP) at these new dose levels. The effects of 3D conformal radiotherapy by RGRD were evaluated with DVH (Dose Volume Histogram), TCP, NTCP and dose statistics. Results : The average movement of a diaphragm was 1.5 cm in the supine position when patients breathed freely. Depending on the location of the tumor, the magnitude of the PTV margin needs to be extended from 1 cm to 3 cm, which can greatly increase normal tissue irradiation, and hence, results in increase of the normal tissue complications probabiliy. Simple and precise RGRD is very easy to setup on patients and is sensitive to length variation (+2 mm), it also delivers on-off information to patients and the LINAC machine. We evaluated the treatment plans of patients who had received conformal partial organ lung irradiation for the treatment of thorax malignancies. Using RGRD, the PTV margin by free breathing can be reduced about 2 cm for moving organs by breathing. TCP values are almost the same values $(4\~5\%\;increased)$ for lung cancer regardless of increasing the PTV margin to 2.0 cm but NTCP values are rapidly increased $(50\~70\%\;increased)$ for upon extending PTV margins by 2.0 cm. Conclusion : Internal organ motion due to breathing can be reduced effectively using our simple RGRD. This method can be used in clinical treatments to reduce organ motion induced margin, thereby reducing normal tissue irradiation. Using treatment planning software, the dose to normal tissues was analyzed by comparing dose statistics with and without RGRD. Potential benefits of radiotherapy derived from reduction or elimination of planning target volume (PTV) margins associated with patient breathing through the evaluation of the lung cancer patients treated with 3D conformal radiotherapy.

• Journal of Chest Surgery
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• v.32 no.5
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• pp.448-455
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• 1999

Background: Recent developments in techniques of video-assisted thoracic surgery(VATS) and endoscopic equipment has expanded the application of video-assisted surgical procedures in the field of thoracic surgery. Especially, it will probably become the treatment of choice of spontaneous pneumothorax(SP). There is, however, a high recurrence rate, high cost, and paucity of long-term results. We report the results of postoperative follow-up and analyze perioperative parameters affected to recurrence, retrospectively. Material and Method: From march 1992 to march 1997, 276 patients with spontaneous pneumothorax underwent 292 VATS procedures. Conversion to open thoracotomy was necessitated in eight patients, and this patients excluded from the study. Result: The sex distribution was 249 males and 31 females. The mean age was 28.1 12.2 years(range, 15 to 69 years). Primary SP was 237cases(83.5%) and secondary SP was 47cases(16.5%). The major underlying lung diseases associated with secondary SP were tuberculosis 27cases(57.4%) and emphysema 8cases (38.3%). Operative indications included Ipsilateral recurrence 123(43.9%), persistent air-leak 53(18.9%), x-ray visible bleb 40(14.3%), tension 30(10.7%), contralateral recurrence 21(7.5%), uncomplicated first episode 8(2.9%), bilateral 3(1.1%), complicated episode 2(0.7%). Blebs were visualized in 247cases(87%) and 244cases(85.9%) performed stapled blebectomy. Early postoperative complications occurred in 33 cases(11.6%): 16 prolonged air-leak more than 5 days(four of them were required a second operation and found missed blebs); 5 bleeding; 5 empyema; 2 atelectasis; 1 wound infection. No deaths occured. The mean operative time was 52.8 23.1 minutes(range, 20 to 165 minutes). The mean d ration of chest tube drainage was 5.0 4.5 days(range, 2 to 37 days). The mean duration ofhospital stay was 8.2 5.5 days (range, 3 to 43days). At a mean follow-up 22.3 18.4 months(range, 1 to 65 months), 12 patients(4.2%) were lost to follow-up. There were 24 recurrences and seven patients underwent second operation and 6 patients(85.7%) were found the missed blebs. 12 perioperative parameters(age, sex, site, underlying disease, extent of collapse, operative indication, size of bleb, number of bleb, location of bleb, bleb management, pleural procedure, prolonged postoperative air-leak) were analyzed statistically to identify significant predictors of recurrence. The significant predictors of recurrence was the underlying disease[17.0%(8/47): 6.8%(16/237), p=0.038], prolonged postoperative air-leakage[37.5%(6/16): 6.7%(18/268), p=0.001], and pleural procedure [11.4%(19/167): 4.3%(5/117), p=0.034]. Blebectomy has less recurrence rate then non-blebectomy [8.2%(20/244) : 10.0%(4/40), p>0. 5]. However, this difference was not statistically significant(p=0.758). Conclusion: We conclude that it is important that we shoud careful finding of bleb during VATS due to reducing of recurrnece, and cases of no bleb identified and secondary spontaneous pneumothorax were indicated of pleurodectomy. VATS is a valid alternative to open procedure for the treatment of spontaneous pneumothorax with less pain, shorter hospital stay, more rapid return to work, high patient acceptance, less scar and exellent cosmetics. But, there is high recurrence rate and high cost, and than it is necessary to evaluate of long-term results for recurrence and to observate carefully during VATS.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.7 no.1
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• pp.31-39
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• 2004

Purpose: Although acute nonspecific mesenteric lymphadenitis (ANML) is probably common cause of abdominal pain in children, which can be severe enough to be an abdominal emergency, the clinical features of mesenteric lymphadenitis are not clear. Also, a differential diagnosis with acute appendicitis (APPE) is indispensable to avoid serious complications. The clinical features of ANML were determined, and the risk factors for differential diagnosis with APPE were analyzed. Methods: Between November 2000 and May 2001, data from 26 patients (aged 1 to 11 years) with ANML and 21 patients (aged 2 to 13 years) with APPE were reviewed. ANML was defined as a cluster of five or more lymph nodes measuring 10 mm or greater in their longitudinal diameter in the right lower quadrant (RLQ) without an identifiable specific inflammatory process on the ultrasonographic examination. There were risk factors on patient's history, physical examination, and laboratory examination; the location of abdominal pain, abdominal rigidity, rebound tenderness, fever, nocturnal pain, the vomiting intensity, the diarrhea intensity, the symptom duration, and the peripheral blood leukocytes count. Results: Of the 26 ANML patients and 21 APPE patients, abdominal pain was noted on periumbilical (76.9% vs 14.2%), on RLQ (11.5% vs 71.4%), with abdomen rigidity (7.6% vs 80.9%), with rebound tenderness (0.0% vs 76.1%)(p<0.05), in the lower abdomen (11.5% vs 14.2%), and at night (80.8% vs 100.0%) (p>0.05). The clinical symptoms were vomiting (38.4% vs 90.4%), the vomiting intensity ($1.5{\pm}0.7$ [1~3]/day vs $4.5{\pm}2.9$ [1~10]/day), diarrhea (65.3% vs 28.5%) (p<0.05), and fever (61.5% vs 76.2%)(p>0.05). The period to the subsidence of abdominal pain in the ANMA patients was $2.5{\pm}0.5$ (2~3) days. The laboratory data showed a significant difference in the peripheral blood leukocytes count ($8,403{\pm}1,737[5,900{\sim}12,300]/mm^3\;vs\;15,471{\pm}3,749[5,400{\sim}20,800]/mm^3$)(p<0.05). Discriminant analysis between ANML and APPE showed that the independent discriminant factors were a vomiting intensity and the peripheral blood leukocytes count and the discriminant power was 95.7%. Conclusion: The clinical characteristics of ANML were abrupt onset of periumbilical pain without rigidity or rebound tenderness, a mild vomiting intensity, normal peripheral leukocytes count, and relatively short clinical course. If the abdominal pain persist for more than 3 days, and/or the vomiting intensity is more than 3 times/day, and/or the peripheral leukocytes count is over $13,500/mm^3$, abdominal ultrasonography is recommended to rule out APPE.

• Radiation Oncology Journal
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• v.23 no.1
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• pp.22-31
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• 2005

Purpose : To conduct a nationwide survey on the principals in radiotherapy for rectal cancer, and produce a database of Korean Patterns of Care Study. Materials and Methods : We developed web-based Patterns of Care Study system and a national survey was conducted using random sampling based on power allocation methods. Eligible patients were who had postoperative radiotherapy for rectal cancer without gross residual tumor after surgical resection and without previous history of other cancer and radiotherapy to pelvis. Data of patients were Inputted to the web based PCS system by each investigators in 19 institutions. Results : Informations on 309 patients with rectal cancer who received radiotherapy between 1998 and 1999 were collected. Male to female ratio was 59 : 41, and the most common location of tumor was lower rectum ($46\%$). Preoperative CEA was checked in $79\%$ of cases and its value was higher than 6 ng/ml in $32\%$. Pathologic stage were I in $1.5\%$, II in $32\%$, III in $53\%$, and IV in $1.6\%$. Low anterior resection was the most common type of surgery and complete resection was peformed in $95\%$ of cases. Distal resection margin was less than 2 cm in $30\%$, and number of lymph node dissected was less than 12 in $31\%$. Chemotherapy was peformed in $91\%$ and most common regimen was 5-FU and leucovorine ($59\%$). The most common type of field arrangement used for the initial pelvic field was the four field box (Posterior-Right-Left) technique ($65.0\%$), and there was no AP-PA parallel opposing field used. Patient position was prone in $81.2\%$, and the boost field was used in $61.8\%$. To displace bowel outward, pressure modulating devices or bladder filling was used in $40.1\%$. Radiation dose was prescribed to isocenter in $45.3\%$ and to isodose line in 123 cases ($39.8\%$). Percent delivered dose over $90\%$ was achieved in $92.9\%$. Conclusion : We could find the Patterns of Care for the radiotherapy in Korean rectal cancer patients was similar to that of US national survey. The type of surgery and the regimen of chemotherapy were variable according to institutions and the variations of radiation dose and field arrangement were within acceptable range.

• Radiation Oncology Journal
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• v.19 no.3
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• pp.216-223
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• 2001

Purpose : We evaluated retrospectively the outcomes of inoperable squamous cell lung cancer patients treated with radiotherapy to find out prognostic factors affecting survival. Materials and methods : Four hundred and eleven patients diagnosed as squamous cell lung cancer between November 1988 and December 1997 were the basis of this analyses. The planned dose to the gross tumor volume was ranged from 30 to 70.2 Gy. Chemotherapy was combined in 72 patients $(17.5\%)$ with the variable schedule and drug combination regimens. Follow-up period ranged from 1 to 113 months with the median of 8 months and survival status was identified in 381 patients $(92.7\%)$. Overall survival rate was calculated using the Kaplan-Meier method. Results : Age ranged from 23 years to 83 years with the median 63 years. The male to female ratio was about 16:1. For all 411 patients, the median overall survival was 8 months and the 1-year survival rate (YSR), 2-YSR, and 5-YSR were $35.6\%,\;12.6\%,\;and\;3.7\%$, respectively. The median and 5-YSR were 29 months and $33.3\%$ for Stage IA, 13 months and $6.3\%$ for Stage IIIA, and 9 months and $3.4\%$ for Stage IIIB, respectively(p=0.00). The median survival by treatment aim was 11 months in radical intent group and 5 months in palliative, respectively (p=0.00). Of 344 patients treated with radical intent, median survival of patients (N=247) who received planned radiotherapy completely was 12 months while that of patients (N=97) who did not was 5 months (p=0.0006). In the analyses of the various prognostic factors affecting to the survival outcomes in 247 patients who completed the planned radiotherapy, tumor location, supraclavicular LAP, SVC syndrome, pleural effusion, total lung atelectasis and hoarseness were statistically significant prognostic factors both in the univariate and multivariate analyses while the addition of chemotherapy was statistically significant only in multivariate analyses. The acute radiation esophagitis requiring analgesics was appeared in 49 patients $(11.9\%)$ and severe radiation esophagitis requiring hospitalization was shown in 2 patients $(0.5\%)$. The radiation pneumonitis requiring steroid medication was shown in 62 patients $(15.1\%)$ and severe pneumonitis requiring hospitalization was occurred in 2 patients $(0.5\%)$. During follow-up, 114 patients $(27.7\%)$ had progression of local disease with 10 months of median time to recur (range : $1\~87\;months$) and 49 patients $(11.9\%)$ had distant failure with 7 months of median value (range : $1\~52\;months$). Second malignancy before or after the diagnosis of lung cancer was appeared in 11 patients Conclusion : The conventional radiotherapy in the patients with locally advanced squamous cell lung cancer has given small survival advantage over supportive care and it is very important to select the patient group who can obtain the maximal benefit and to select the radiotherapy technique that would not compromise the life quality in these patients.