• Radiation Oncology Journal
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• v.18 no.4
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• pp.293-299
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• 2000

Purpose :We conducted a prospective non-randomized clinical study to evaluate the efficacy and toxic of the preoperative concurrent chemoradiotherapy for locally advanced unresectable rectal cancer. Materials and Methods: Between January 1995 and June 1998, 37 conecutive patients with locally unresectable advanced rectal cancer were entered into the study. With 3- or 4- fields technique, a total of 45 Gy radiation was delivered on whole pelvis, followed by 5.4 Gy boost to the primary tumor in some cases. Chemotherapy was done at the first and fifth week of radiation with bolus i.v. 5-Fluorouracil (FU) 370$\~$450 mg/m$^{2}$, days 1$\~$5, plus Leucovorin 20 mg/m$^{2}$, days 1$\~$5. OF 37 patients, 6 patients did not receive all planned treatment course (refusal in 4, disease progression in 1, metastasis to lung in 1). Surgical resection was undergone 4$\~$6 weeks after preoperative concurrent chemoradiotherapy. Results :Complete resection rate with negative margins was 94$\%$ (29/31). Complete response was seen in 7 patients (23$\%$) clinically and 2 patients (6$\%$) pathologically. Down staging of tumor occured in 21 patients (68$\%$). Treatment related toxicity was minimal except grade III & IV leukopenia in 2 patients, respectively. Conclusion : Preoperative concurrent chemoradiotherapy in locally advanced rectal cancer was effective in inducing down staging and complete resection rate. Treatment related toxicity was minimal. Further follow up is on-going to determine long term survival following this treatment.

• Radiation Oncology Journal
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• v.11 no.2
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• pp.295-301
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• 1993

Since Jan. 1991 a prospective randomized study for Stage III unresectable non small cell lung cancer (NSCLC) has been conducted to evaluate the response rate and tolerance of induction chemotherapy with MVP followed by hyperfractionated radiotherapy and evaluate the efficacy of maintenance chemotherapy in Asan Medical Center. All patients in this study were treated with hyperfractionated radiotherapy (120 cGy/fx BID, 6480 cGy/54 fx) following 3 cycles of induction chemotherapy, MVP (Mitomycin C 6 $mg/m^2,$ Vinblastin 6 $mg/m^2,$ Cisplatin 60 $mg/m^2$) and then the partial and complete responders from induction chemotherapy were randomized to 3 cycles of adjuvant MVP chemotherapy group and observation group. 48 patients were registered to this study until December 1992; among 48 patients 3 refused further treatment after induction chemotherapy and 6 received incomplete radiation therapy because of patient's refusal, 39 completed planned therapy. Twenty-three $(58\%)$ patients including 2 complete responders showed response from induction chemotherapy. Among the 21 patients who achieved a partial response after induction chemotherapy,1 patient rendered complete clearance of disease and 10 patients showed further regression of tumor following hyperfractionated radiotherapy. Remaining 10 patients showed stable disease or progression after radiotherapy. Of the sixteen patients judged to have stable disease or progression after induction chemotherapy, seven showed more than partial remission after radiotherapy but nine showed no response in spite of radiotherapy. Of the 39 patients who completed induction chemotherapy and radiotherapy, 25 patients $(64\%)$ including 3 complete responders showed more than partial remission. Nineteen patients were randomized after radio-therapy. Nine Patients were allocated to adjuvant chemotherapy group and 4/9 showed further regression of tumor after adjuvant chemotherapy. For the time being, there is no suggestion of a difference between the adjuvant chemotherapy group and observation group in distant metastasis rate and survival. Median survival time was 13 months. Actuarial survival rates at 6,12 and 18 months of 39 patients who completed this study were $84.6\%,\;53.7\%\;and\;40.3\%,$ respectively. The partial and complete responders from induction chemotherapy showed significantly better survival than non-responders (p=0.028). Incidence of radiation pneumonitis in this study group was less than that in historical control group inspite of induction chemotherapy. All patients tolerated hypertractionated radiotherapy without definite increase of acute complications compared with conventional radiotherapy group. The longer follow up is needed to evaluate the efficacies of induction and maintenance chemotherapy and survival advantage by hyperfractionated radiotherapy but authors are encouraged with an excellent tolerance, higher response rate and improvement of one year survival rate in patients of this study.

• The Journal of Korean Society for Radiation Therapy
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• v.27 no.2
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• pp.157-166
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• 2015

Purpose : Cyber-Knife tumor tracking system, based on the correlation relationship between the position of a tumor which moves in response to the real time respiratory cycle signal and respiration was obtained by the LED marker attached to the outside of the patient, the location of the tumor to predict in advance, the movement of the tumor in synchronization with the therapeutic device to track real-time tumor, is a system for treating. The purpose of this study, in the cyber knife tumor tracking radiation therapy, trying to evaluate the accuracy of tumor tracking radiation therapy system due to the change in the form of unpredictable sudden breathing due to cough and sleep. Materials and Methods : Breathing Log files that were used in the study, based on the Respiratory gating radiotherapy and Cyber-knife tracking radiosurgery breathing Log files of patients who received herein, measured using the Log files in the form of a Sinusoidal pattern and Sudden change pattern. it has been reconstituted as possible. Enter the reconstructed respiratory Log file cyber knife dynamic chest Phantom, so that it is possible to implement a motion due to respiration, add manufacturing the driving apparatus of the existing dynamic chest Phantom, Phantom the form of respiration we have developed a program that can be applied to. Movement of the phantom inside the target (Ball cube target) was driven by the displacement of three sizes of according to the size of the respiratory vertical (Superior-Inferior) direction to the 5 mm, 10 mm, 20 mm. Insert crosses two EBT3 films in phantom inside the target in response to changes in the target movement, the End-to-End (E2E) test provided in Cyber-Knife manufacturer depending on the form of the breathing five times each. It was determined by carrying. Accuracy of tumor tracking system is indicated by the target error by analyzing the inserted film, additional E2E test is analyzed by measuring the correlation error while being advanced. Results : If the target error is a sine curve breathing form, the size of the target of the movement is in response to the 5 mm, 10 mm, 20 mm, respectively, of the average $1.14{\pm}0.13mm$, $1.05{\pm}0.20mm$, with $2.37{\pm}0.17mm$, suddenly for it is variations in breathing, respective average $1.87{\pm}0.19mm$, $2.15{\pm}0.21mm$, and analyzed with $2.44{\pm}0.26mm$. If the correlation error can be defined by the length of the displacement vector in the target track is a sinusoidal breathing mode, the size of the target of the movement in response to 5 mm, 10 mm, 20 mm, respective average $0.84{\pm}0.01mm$, $0.70{\pm}0.13mm$, with $1.63{\pm}0.10mm$, if it is a variant of sudden breathing respective average $0.97{\pm}0.06mm$, $1.44{\pm}0.11mm$, and analyzed with $1.98{\pm}0.10mm$. The larger the correlation error values in both the both the respiratory form, the target error value is large. If the motion size of the target of the sine curve breathing form is greater than or equal to 20 mm, was measured at 1.5 mm or more is a recommendation value of both cyber knife manufacturer of both error value. Conclusion : There is a tendency that the correlation error value between about target error value magnitude of the target motion is large is increased, the error value becomes large in variation of rapid respiration than breathing the form of a sine curve. The more the shape of the breathing large movements regular shape of sine curves target accuracy of the tumor tracking system can be judged to be reduced. Using the algorithm of Cyber-Knife tumor tracking system, when there is a change in the sudden unpredictable respiratory due patient coughing during treatment enforcement is to stop the treatment, it is assumed to carry out the internal target validation process again, it is necessary to readjust the form of respiration. Patients under treatment is determined to be able to improve the treatment of accuracy to induce the observed form of regular breathing and put like to see the goggles monitor capable of the respiratory form of the person.

• Radiation Oncology Journal
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• v.15 no.4
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• pp.369-377
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• 1997

Purpose : This study was Performed to identify the histopathologic feature by the reevaluation of the Pathologic specimen of the cervical tumors and to evaluate the clinical findings and the treatment results of the patients with small cell carcinoma of the cervix treated by radiotherapy. Materials and Methods : 2890 patients with cervical carcinoma received radiotherapy at the Department of Radiation Oncology. Yonsei Cancer Center, Yonsei University College of Medicine between October 1981 and April 1995. Of the 2890 patients in this data base, sixty were found to have small cell carcinomas $(2.08\%)$. Among them thirty six patients were transferred from other hospitals. the biopsy specimens of those Patients were not available. So we could review the slides of the other twenty four patients who were diagnosed at our hospital. Twenty four patients with small cell carcinoma of the cervix were analyzed retrospectively based on the assessment of H & E staining and other four immunohistochemical stains for neuroendocrine differentiation (neuron specific enolase, chromogranin. synaptophysin and Grimelius stain). And we also evaluate the Patients and tumor characteristics. response to radiation. patterns of failures, 5 year overall and disease free survival rates. Results : Thirteen tumors were neuroendocrine carcinomas(13/24 = $54.2\%$) and eleven tumors were squamous carcinomas, small cell type (11/24 = $47.8\%$) based on the assessment of H & E staining and other four neuroendocrine marker studies. So we classified the Patients two groups as neuroendocrine carcinoma and small cell type of squamous carcinoma, Among the 13 neuroendocrine carcinomas, five were well to moderately differentiated tumors and the other eight were Poorly differentiated or undifferentiated ones. The median age was 54 years old (range 23-79 years). Eight Patients had FIGO stage IB disease, 12 had stage 11, 3 had stage III and one had stage IV disease, Pelvic lymph node metastases were found in five Patients $(20.8\%)$. three of them were diagnosed by surgical histologic examination and the other two were diagnosed by CT scan. There was no difference between two histopathologic groups in terms of patients and tumor characteristics. response to radiation. 5 year overall and disease free survival rates. However the distant metastases rate was higher in neuroendocrine carcinoma Patients (6/13:$46.2\%$) than in small cell type of squamous carcinoma Patients (2/11:$18.2\%$), but there was no statistically significant difference because of the small number of patients (P>0.05). Conclusion : More than half of the small cell carcinoma of the cervix patients were neuroendocrine carcinoma (13/24 : $54.1\%$) by reevaluation of the biopsy specimen of the cervical tumors. The tendency of distant metastases of the neurolndocrine carcinoma was greater than those of the small cell type of squamous carcinoma $(46.2\%\;vs.\;18.2\%)$. But there were no differences in the patients and tumor characteristics and other clinical treatment results in both groups. These data suggest that radical local treatment such as radiotherapy or radical surgery combined with combination systemic cytotoxic chemotherapy might provide these patients with the best chance for cure.

• The Korean Journal of Nuclear Medicine
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• v.35 no.2
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• pp.83-88
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• 2001

Purpose: The purpose of this study was to ascertain whether radiation adaptive response could be induced by high dose I-131 therapy in patients with differentiated thyroid cancer. Materials and Methods: Lymphocytes from 21 patients (7 males, 14 females, mean age $55{\pm}12$ years) were collected before and after administration of 5,550 MBq (150 mCi) I-131. They were exposed to a challenge dose of 1 Gy gamma rays using a Cs-137 cell irradiator. The number of ring-form (R) and dicentric (D) chromosomes was counted under the light microscope, and used to calculate the frequency of chromosomal aberration. Ydr, which was defined as the sum of R and D divided by the total number of counted lymphocytes. Results: Ydr in patients before I-131 therapy ($0.09{\pm}0.01$) was not different from that of controls ($0.08{\pm}0.01$). Ydr was significantly increased to $0.13{\pm}0.02$ (p<0.0001) after I-131 therapy. Increase of Ydr after the challenge irradiation of 1 Gy was significantly lower in patients after I-131 therapy than before I-131 therapy ($0.17{\pm}0.03\;vs\;0.21{\pm}0.02$, p<0.0001). Cycloheximide (CHM), an inhibitor of protein synthesis, abolished this effect. Ydr after CHM ($0.20{\pm}0.01$) was significantly higher than Ydr after I-131 therapy ($0.17{\pm}0.03$, p<0.0001), but was not different from Ydr before I-131 therapy ($0.21{\pm}0.02$).Conclusion: High dose I-131 therapy induces an adaptive response in peripheral lymphocytes of patients with well-differentiated thyroid cancer, which is associated with protein synthesis.

• Tuberculosis and Respiratory Diseases
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• v.63 no.2
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• pp.154-164
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• 2007

Background: Irinotecan hydrochloride, a topoisomerase I inhibitor, is effective against small-cell lung cancer. Irinotecan also can act as a potential radiation sensitizer along with cisplatin. To evaluate efficacy and toxicity of irinotecan plus cisplatin (IP) with concurrent thoracic radiotherapy, we conducted a phase II study of IP followed by concurrent IP plus hyperfractionated thoracic radiotherapy in patients with previously untreated limited-stage small-cell lung cancer. Methods: Twenty-four patients with previously untreated small-cell lung cancer were enrolled onto the study since November 2004. Irinotecan $60mg/m^2$ was administered intravenously on days 1 and 8 in combination with cisplatin $60mg/m^2$ on day1 every 21 days. From the first day of third cycle, twice-daily thoracic irradiation (total 45 Gy) was given. Prophylactic cranial irradiation was given to the patients who showed complete remission after concurrent chemoradiotherapy. Restaging was done after second and sixth cycle with chest CT and/or bronchosocpy. Results: Up to November 2004, 19 patients were assessable. The median follow-up time was 12.5 months. A total of 99 cycles (median 5.2 cycles per patient) were administered. The actual dose intensity values were cisplatin $19.6mg/m^2$/week and irinotecan $38.2mg/m^2$/week. Among the 19 patients, the objective response rate was 95% (19 patients), with 9 patients (47%) having a complete response (CR). The major grade 3/4 hematological toxicities were neutropenia (35% of cycles), anemia (7% of cycles), thrombocytopenia (7% of cycles). Febrile neutropenia was 4% of cycles. The predominant grade 3/4 non-hematological toxicities was diarrhea (5% of cycles). Toxicities was not significantly different with concurrent administration of irinotecan and cisplatin with radiotherapy, except grade 3/4 radiation esophagitis (10% of patients). No treatment-related deaths were observed. The 1-year and 2-year survival rate of eligible patients was 89% (16/18) and 47% (9/18), respectively. Conclusion: Three-week schedule of irinotecan plus cisplatin followed by concurrent IP plus hyperfractionated thoracic radiotherapy is an effective treatment for limited disease small-cell lung cancer, with acceptable toxicity.

• Radiation Oncology Journal
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• v.16 no.1
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• pp.51-61
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• 1998

Purpose : Treatment of choice for uterine cervix cancer stage IIB is radiotherapy. We analyzed survivals, Prognostic factors, patterns of failure and complications. Materials and Methods : This is a retrospective analysis of 167 patients with stage IIB carcinoma of uterine cervix treated with curative external pelvic and high dose rate intracavitary radiotherapy at the Department of Therapeutic Radiology, Soonchunhyang University Hospital from August 1985 to August 1994. All the patients followed up from 3 to 141 months(mean 60 months) and age of patients ranged from 31 to 78 years at presentation(mean : 55 years). Results : Overall complete response rate was $84\%$. The response rate for squamous cell carcimoma and adenocarcinoma were $86\%$ and $60\%$, respectively. Overall 5-years survival rate and disease free survival rate was 62 and $59\%$, respectively Mass size and treatment response were significant Prognostic factors for survival Pathologic type and parametrial involvement were marginally significants Prognostic factors. Local failure was 43 cases, distant metastasis was 14 cases and local failure plus distant metastasis was 3 cases, and most of local failures occurred within 24 months, distant metastasis within 12 months after treatment Twenty eight($16.8\%$) patients developed late rectal and urinary complications There were tendency to increasing severity and frequency according to increased fractional dose and total(rectal and bladder) dose. Conclusions : Survival rate was significantly related to tumor size and radiotherapy response. Tumor size should be considered in the clinical s1aging. To increased survival and local control, clinical trials such as decreasing duration of radiotherapy or addition of chemotherapy is needed. To detect early recurrence, regular follow up after RT is important. Because total rectal and bladder dose affected late complications. meticulous vaginal packing is needed to optimize dose of normal tissues and to decrease late complications.

• Radiation Oncology Journal
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• v.23 no.3
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• pp.143-156
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• 2005

Background: The best dose-fractionation regimen of the definitive radiotherapy for cervix cancer remains to be clearly determined. It seems to be partially attributed to the complexity of the affecting factors and the lack of detailed information on external and intra-cavitary fractionation. To find optimal practice guidelines, our experiences of the combination of external beam radiotherapy (EBRT) and high-dose-rate intracavitary brachytherapy (HDR-ICBT) were reviewed with detailed information of the various treatment parameters obtained from a large cohort of women treated homogeneously at a single institute. Materials and Methods: The subjects were 743 cervical cancer patients (Stage IB 198, IIA 77, IIB 364, IIIA 7, IIIB 89 and IVA 8) treated by radiotherapy alone, between 1990 and 1996. A total external beam radiotherapy (EBRT) dose of $23.4\~59.4$ Gy (Median 45.0) was delivered to the whole pelvis. High-dose-rate intracavitary brachytherapy (HDR-IBT) was also peformed using various fractionation schemes. A Midline block (MLB) was initiated after the delivery of $14.4\~43.2$ Gy (Median 36.0) of EBRT in 495 patients, while In the other 248 patients EBRT could not be used due to slow tumor regression or the huge initial bulk of tumor. The point A, actual bladder & rectal doses were individually assessed in all patients. The biologically effective dose (BED) to the tumor ($\alpha/\beta$=10) and late-responding tissues ($\alpha/\beta$=3) for both EBRT and HDR-ICBT were calculated. The total BED values to point A, the actual bladder and rectal reference points were the summation of the EBRT and HDR-ICBT. In addition to all the details on dose-fractionation, the other factors (i.e. the overall treatment time, physicians preference) that can affect the schedule of the definitive radiotherapy were also thoroughly analyzed. The association between MD-BED $Gy_3$ and the risk of complication was assessed using serial multiple logistic regression models. The associations between R-BED $Gy_3$ and rectal complications and between V-BED $Gy_3$ and bladder complications were assessed using multiple logistic regression models after adjustment for age, stage, tumor size and treatment duration. Serial Coxs proportional hazard regression models were used to estimate the relative risks of recurrence due to MD-BED $Gy_{10}$, and the treatment duration. Results: The overall complication rate for RTOG Grades $1\~4$ toxicities was $33.1\%$. The 5-year actuarial pelvic control rate for ail 743 patients was $83\%$. The midline cumulative BED dose, which is the sum of external midline BED and HDR-ICBT point A BED, ranged from 62.0 to 121.9 $Gy_{10}$ (median 93.0) for tumors and from 93.6 to 187.3 $Gy_3$ (median 137.6) for late responding tissues. The median cumulative values of actual rectal (R-BED $Gy_3$) and bladder Point BED (V-BED $Gy_3$) were 118.7 $Gy_3$ (range $48.8\~265.2$) and 126.1 $Gy_3$ (range: $54.9\~267.5$), respectively. MD-BED $Gy_3$ showed a good correlation with rectal (p=0.003), but not with bladder complications (p=0.095). R-BED $Gy_3$ had a very strong association (p=<0.0001), and was more predictive of rectal complications than A-BED $Gy_3$. B-BED $Gy_3$ also showed significance in the prediction of bladder complications in a trend test (p=0.0298). No statistically significant dose-response relationship for pelvic control was observed. The Sandwich and Continuous techniques, which differ according to when the ICR was inserted during the EBRT and due to the physicians preference, showed no differences in the local control and complication rates; there were also no differences in the 3 vs. 5 Gy fraction size of HDR-ICBT. Conclusion: The main reasons optimal dose-fractionation guidelines are not easily established is due to the absence of a dose-response relationship for tumor control as a result of the high-dose gradient of HDR-ICBT, individual differences In tumor responses to radiation therapy and the complexity of affecting factors. Therefore, in our opinion, there is a necessity for individualized tailored therapy, along with general guidelines, in the definitive radiation treatment for cervix cancer. This study also demonstrated the strong predictive value of actual rectal and bladder reference dosing therefore, vaginal gauze packing might be very Important. To maintain the BED dose to less than the threshold resulting in complication, early midline shielding, the HDR-ICBT total dose and fractional dose reduction should be considered.

• Progress in Medical Physics
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• v.20 no.4
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• pp.308-316
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• 2009

To achieve the accurate evaluation of given absorbed dose from output dose of linear accelerator photon beam through investigate the characteristics of LiF:Mg,Cu,P TLD powder. This experimental TL phosphor is performed with a commercial LiF:Mg,Cu,P powder (Supplied by PTW) and TL reader (LTM, France). The TLD was exposed to 6 MV X rays of linear accelerator photon beam with range 15 to 800 cGy in blind dose at two hospitals. The dose evaluation of TLD was through the experimental algorithms which were dose dependency, dose rate dependency, fading and powder weight dependency. The glow curve has shown the three peaks which are 110, 183 and 232 degrees of heating temperature and the main dosimetric peak showed highest TL response at 232 high temperature. In this experiments, the LiF:Mg,Cu,P phosphor has shown the 2.5 eV of electron trap energy with a second order. This experiments guided the dose evaluation accuracy is within 1% +2.58% of discrepancy. The TLD powder of LiF:Mg,Cu,P was analyzed to dosimetric characterists of electron captured energy and order by glow shape, and dose-TL response curve guided the accuracy within 1.0+2.58% of output dose discrepancy.

• Radiation Oncology Journal
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• v.13 no.4
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• pp.311-319
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• 1995

Purpose : To evaluate the survival and prognostic factors in patients with stage III non-small cell lung cancer treated with curative radiotherapy alone or combined with chemotherapy Materials and Methods : A retrospective analysis was undertaken of 35 patients who had locally advanced non-small-cell lung cancer and treated with curative radiotherapy in Department of Therapeutic Radiology, Kangdong Sacred Heart Hospital, from January 1991 through December 1993. According to AJCC staging, 15 patients were stage IIIA, and 20 were stage IIIB. Radiotherapy was delivered with 1 8-2 Gy per fraction/day. 5 days per week using 6 MV X-ray, to a total dose ranging from 48.8 Gy to 66.6 Gy (median, 61.2 Gy) in 4 to 9 weeks. Ten patients received neoadjuvant or concurrent chemotherapy with FIP (5-FU, ifosfamide, and cisplatin) or FP (5-FU and cisplatin) Results : For all Patients, median survival was 6 months. 1-year and 2-year survival rates were 23.3% and 6.7%, respectively The median survival was 8 months in stage IIIA and 5.5 months in stage IIIB. In patients treated with radiation therapy alone, median survival was 5 months and 1-year survival rate was 9%. In patients who received chemotherapy, median survival was 11 months and 1-year survival rate was 60%. The difference of survival between these two groups was statistically significant (p=0.03). Total radiation dose, degree of response, and Post-treatment ECOG score were also significantly associated with survival. But it was not affected by age, sex, pretreatment ECOG score, presence or absence of weight loss, tumor location. pathologic type, N stage, and degree of response to treatment. Conclusion : Conventional radiotherapy alone is unlikely to achieve long term survival in patients with stage III NSCLC. Radiotherapy with altered fractionation schedule or multimodality treatment combined with surgery and/or chemotherapy should be considered if feasible.