• Radiation Oncology Journal
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• v.19 no.2
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• pp.142-145
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• 2001

Purpose : Acute leukemia with hyperleukocytosis (more than $10^5/mm^3$) is at high risk of early sudden death, usually from intracerebral hemorrhage. Emergency cranial irradiation is a relatively simple approach to solve this the problem. We summarized our experience of cranial irradiation in 24 leukemic children who presented with hyperleukocytosis. Methods and Materials : Between 1990 and 1998, 40 children with acute leukemia presenting with hyperleukocytosis were referred for emergency cranial irradiation. Among these patients, 24 children were evaluable. There were 16 boys and eight girls, their ages ranged from 2 to 13 years (median 9.5 years). The initial leukocyte counts ranged $109,910/mm^3\;to\;501,000/mm^3$. Peripheral blood smear was peformed in all patients and noted the morphology of the blast. Introduction of emergency cranial irradiation was determined by the leukocyte counts (more than 100,000/mm) and the existence of the blast in peripheral blood smear. All patients were treated with intravenous hydration with alkaline fluid and oral allopurinol. Cranial irradiation started on the day of diagnosis. With 2 Gy in one fraction in 4 patients, 4 Gy in two fractions in 20 patients. Results : The WBC count had fallen in 19 patients (83%) and no intracerebral hemorrhage occurred after irradiation. There were five cases of early deaths. Four patients died of metabolic complications, and one patient with intracerebral hemorrhage. He died 5 hours after cranial irradiation. No patient had any immediate side effect from cranial irradiation. Conclusion : Our data suggest, that emergency cranial irradiation can be safely chosen and effective in childhood leukemic patients presenting with high leukocyte counts.

• Radiation Oncology Journal
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• v.20 no.2
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• pp.123-129
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• 2002

Purpose : The purpose of this study 띤as to determine the potential role of three-dimensional conformal radiotherapy (3D-CRT) in the treatment of primary unresectable hepatocellular carcinoma. The preliminary results on the efficacy and the toxicity of 3D-CRT are reported. Materials and Methods : Seventeen patients were enrolled in this study, which was conducted prospectively from January 1995 to June 1997. The exclusion criteria included the presence of extrahepatic metastasis, liver cirrhosis of Child-Pugh classification C, tumors occupying more than two thirds of the entire liver, and a performance status of more than 3 on the ECOG scale. Two patients were treated with radiotherapy only while the remaining 15 were treated with combined transcatheter arterial chemoembolization. Radiotherapy was given to the field including the tumor plus a 1.5 cm margin using a 3D-CRT technique. The radiation dose ranged from $36\~60\;Gy$ (median; 59.4 Gy). Tumor response was based on a radiological examination such as the CT scan, MR imaging, and hepatic artery angiography at $4\~8$ weeks following the completion of treatment. The acute and subacute toxicities were monitored. Results : An objective response was observed in 11 out of 17 patients, giving a response rate of $64.7\%$. The actuarial survival rate at 2 years was $21.2\%$ from the start of radiotherapy (median survival; 19 months). Six patients developed a distant metastasis consisting of a lung metastasis in 5 patients and bone metastasis in one. The complications related to 30-CRT were gastro-duodenitis $(\geq\;grade\;2)$ in 2 patients. There were no treatment related deaths and radiation induced hepatitis. Conclusion : The preliminary results show that 3D-CRT is a reliable and effective treatment modality for primary unresectable hepatocellular carcinoma compared to other conventional modalities. Further studies to evaluate the definitive role of the 3D-CRT technique in the treatment of primary unresectable hepatocellular carcinoma are needed.

• Progress in Medical Physics
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• v.25 no.3
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• pp.167-175
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• 2014

The purpose of this study is to evaluate the variation of the dose which is delivered to the patients with glottis cancer under IMRT (intensity modulated radiation therapy) by using the 3D registration with CBCT (cone beam CT) images and the DIR (deformable image registration) techniques. The CBCT images which were obtained at a one-week interval were reconstructed by using B-spline algorithm in DIR system, and doses were recalculated based on the newly obtained CBCT images. The dose distributions to the tumor and the critical organs were compared with reference. For the change of volume depending on weight at 3 to 5 weeks, there was increased of 1.38~2.04 kg on average. For the body surface depending on weight, there was decreased of 2.1 mm. The dose with transmitted to the carotid since three weeks was increased compared be more than 8.76% planned, and the thyroid gland was decreased to 26.4%. For the physical evaluation factors of the tumor, PITV, TCI, rDHI, mDHI, and CN were decreased to 4.32%, 5.78%, 44.54%, 12.32%, and 7.11%, respectively. Moreover, $D_{max}$, $D_{mean}$, $V_{67.50}$, and $D_{95}$ for PTV were increased or decreased to 2.99%, 1.52%, 5.78%, and 11.94%, respectively. Although there was no change of volume depending on weight, the change of body types occurred, and IMRT with the narrow composure margin sensitively responded to such a changing. For the glottis IMRT, the patient's weight changes should be observed and recorded to evaluate the actual dose distribution by using the DIR techniques, and more the adaptive treatment planning during the treatment course is needed to deliver the accurate dose to the patients.

• The Journal of Korean Society for Radiation Therapy
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• v.30 no.1_2
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• pp.35-40
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• 2018

Purpose : The range of force differs from the size of proton energy used in our hospital. The compensator enables to change energy size based on distal thickness which also makes changes in dose rate. Therefore, the purpose of this study is to evaluate the effect of changing the thickness of compensator distal on dose range and beam on time. Subject and Methodology : Five low energy patients who have received proton therapy were selected as subjects for this study. Beam on was checked for the selected patients during the existing therapy. After then, the thickness of distal of compensator was increased by 2 cm up to 14 cm through proton therapy plan system(TPS) for comparative analysis. For the evaluation of dose range, the value of the target's conformity index(CI) and the maximum dose of rear side target's organ at risk(OAR) were compared. Furthermore, to evaluate the effect of therapy time, beam on time was compared by making compensator distal in each thickness. Result : The result of homogeneity index and conformity index of the increased compensator distal showed the same level in all patients. The comparison results of OAR of target rear side showed 7 cGy at spine cord of abdomen at maximum, 88 cGy at eyeball's RT lens, 391 cGy at RT lens of nasal cavity 51 cGy at trachea of the mediastinum, and 661 cGy at a small bowl of the pelvis. The comparison results of the beam on time showed a reduction from 126 seconds to 62 seconds for the abdomen, from 105 seconds to 37 seconds for the eyeball, from 187 seconds to 134 seconds for nasal cavity, from 100 seconds to 40 seconds for mediastinum, from 440 seconds to 118 seconds for the pelvis. Conclusion : The research result showed that as the distal thickness of compensator increased, the size of energy increased. In addition, beam on decreased due to the increase of dose rate. It is expected that the result would help reduce the treatment time and increase the convenience of patients if it is applied to liver patients who need respiratorygated therapy and pediatric patients. However, distal penumbra increased as the size energy increased. Therefore, in treating cases where OAR is in the vicinity of the target rear side, the influence of penumbra should be taken into account in adjusting thickness level of the compensator in proton therapy plan.

• Radiation Oncology Journal
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• v.14 no.1
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• pp.9-15
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• 1996

Purpose: The traditional approach with surgery and/or radiotherapy(RT) for advanced head and neck cancer Provides anticipated cure rates of $10-65\%$ depending on stages and sites. Recently, combined modality with chemotherapy have been extensively investigated in attempts to improve survival and local control. We retrospectively analysed our experience of 31 patients with advanced head and neck cancer. Materials and Methods : November 1983 to October 1994. 31 Patients with Stage III and IV squamous cell head and neck cancer were treated with RT. Sixteen patients were treated with RT alone, and IS patients were treated with combined RT plus chemotherapy. All patients were treated with 4-MV LINAC and radiation dose ranged from 5000 cGy to 7760 cGy (median 7010 cGy). In combined group, 7 patients were treated with cisplatin plus 5-FU 2 patients were treated with methotrexate plus leucovorin plus 5-FU plus cisplatin or carboplatin, and 6 patients were treated with cisplatin as a radiosensitizer. Results : Median follow up period was 16 months (range 4-134 months). The major responses (CR+PR) were noted in 10 patient ($66.6\%$) of the RT alone group and 14 patient ($93.3\%$) of the chemoradiation group. There was no statistical difference in CR rate between the two groups The overall survival rates at 5 years were $23.4\%$ in the radiation alone group, $23.5\%$ in the chemoradiation group Disease-free survival rates at 3 years were $44.5\%$ in the radiation alone group, $40\%$ in the chemoradiation group. There was no statistical differences in overall survival rates and disease-free survival rates between the two groups. Local recurrences occurred in $71.5\%$ of the radiation alone group, $72.7\%$ of the chemoradiation group and distant metastasis occurred in $14.4\%$ of radiation alone group, $9.1\%$ of the chemoradiation group. The frequencies of complications were comparable in both groups except hematologic toxicity Conclusion : Total response rates in the combined chemotherapy and radiotherapy was relatively higher than radiotherapy alone. But our result failed to show any survival benefit of the combined chemotherapy and radiotherapy. The accrual of large number of patients and long term follow-un may be necessary to confirm the present result of combined chemotherapy and radiotherapy.

• The Journal of Korean Society for Radiation Therapy
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• v.18 no.2
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• pp.97-103
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• 2006

The purpose of this study is to understand preliminary education. level of understanding and the degrees of educational requirement for cancer patients on radiotherapy and to present the preliminary data to development of effective and practical patients treatment programs. Based on the abovementioned results of this study. Relationship betweendegrees of knowledge and demand for educational requirement for patients who are undertaking radiotherapy could be varied with different factors such as educational background, ages, regions of treatment, experience of symptoms. In general, patients do not have enough information, on the other hand, have very high demand for educational requirement. Customized education patients by patients would not be possible in reality. However, if we could provide standard for patients and establish systematic sessions during treatment based on this study, more and better patients satisfaction and results of treatments could be achieved.

• Radiation Oncology Journal
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• v.21 no.4
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• pp.269-275
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• 2003

Purpose: To evaluate the results of radiation management on recurrence, survival and prognostic factors of patients with nasopharyngeal cancer Materials and Methods: Forty-nine patients, treated for nasopharyngeal cancer by radiotherapy between January 1984 and June 2000, were retrospectively studied. All patients were followed up for at least 2.5 years. Their median age was 52 years (range 17$\~$78). The histological types were 21 squamous cell carcinoma, 25 undifferentiated carcinoma, and 3 adenoid cystic carcinoma. The tumor stages were as follows: T1 in 14 patients, T2 in 24, T3 in 3, and T4 in 8, and N0 in 17 patients, Nl in 15, N2 in 4 and N3 in 13. Stages I, IIa, IIb ,III, IV and IVb were 4, 7, 12, 5, 8, and 13 patients respectively. Radiation doses of 58$\~$70 Gy (median 68.7 Gy) were given to the nasopahryngeal and involved lymphatic areas and of 46 $\~$ 50 Gy to the uninvolved neck areas. Results: The overall 5 and 10-year actuarial and disease free survival rates were 54.53$\%$ and 47$\%$ and 55.7$\%$ and 45.3$\%$, respectively The overall five-year survival rates were 100$\%$ in stage I , 80$\%$ in stage IIa, 59.5$\%$ in stage IIIb, 40$\%$ in stage III, and 42.2$\%$ in stage IV tumors. Twenty-three patients fatted either loco-regionally or distantly. Incidences of local failure, regional failure and distant metastasis for the first failure were 20.4$\%$, 8.2$\%$ and 20.4$\%$, respectively. Local recurrences were 4.3$\%$ in T1, 12.5$\%$ in T2, 0$\%$ in T3, and 62.5$\%$ in T4 lesions. Distant metastasis was seen in 41.2$\%$ of N2-3 lesions. Fifty percent of local recurrence appeared within 2 years of treatment at the primary lesion, whereas 70$\%$ of distant metastasis appeared within 2 years following treatment. Young age, female, early T stage, N0 stage; and poorly differentiated carcinoma were all related with good survival. However only stage showed statistically significance. Conclusionn: Based on the results of this study, radiation therapy to nasopharyngeal cancer showed high local recurrence in T4 and increased metastasis in N2-3 lesions. To improve local failure, further radiation doses, such as stereotactic radiation or IMRT radiation, are necessary especially in T4 lesions. The high incidence of distant metastasis in positive lymph node patients, indicates that combined radiation and effective chemotherapeutic agents with appropriated schedule are necessary.

• Radiation Oncology Journal
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• v.15 no.3
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• pp.233-241
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• 1997

Purpose : This study was done to evaluate the survival rate and Prognostic factors of patients with inoperable non-small cell lung cancer(NSCLC) treated with radiation therapy. Materials and Methods A retrospective analysis was undertaken of 62 Patients who had inoperable NSCLC treated with radiation therapy from January 1991 through December 1993. According to AJCC slaging, stage IIIA was 14 patients and stage IIIB was 48 patients. Forty Gy to 70.2Gy to the primary tumor site was delivered with daily fractions of 1.8Gy or 2Gy, 5days per week. Thirty-seven patients received neoadjuvant chemotherapy. Results : Complete, partial and no response to radiation therapy were 3 patients, 34 Patients and 25 patients, respectively The median survival period of all patients was 11 month. One rear survival rate, 2 year survival rateand 5 rear survival rate for all patients were 45.0%, 14.3%, and 6.0% respectively The median survival period was 6.5 months in stage IIIA and 13 months in stage IIIB. One year survival rates were 28.6% in stage IIIA and 50.3% in stage IIIB In univariaite analysis, prognostic factors affecting survival were T-s1aging, AJCC staging, and response after radiation therapy (P<0.05) . Pretreatment peformance status affected survival but was not statistically significant (0.050.1). In multivariate analysis, Pathology and response to radiation therapy are independently significant prognostic factor. T stage was marginally significant (P=0.0809). During follow-up duration, distant metastasis developed in 20 patients-bone metastasis in 10 patients, brain metastasis in 3 patients, liver mentastasis in 3 patients, contralateral lung metastasis in 1 patients and multiple metastases in 3 patients. Conclusion :　Conventional radiotherapy alone or combined chemoradiotherapy are unlikely to achieve long term survival in patients with NSCLC.　Surgery after concurrent chemoradiotherapy is Ivied to improve the local　control in our hospital

• Radiation Oncology Journal
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• v.15 no.3
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• pp.225-231
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• 1997

Purpose : Radiation therapy in combination with surgery has an important role in the therapy of the head and neck cancer We conducted a prospective study for patients with head and neck cancer treated with surgery and radiation to evaluate the effect of therapies on the thyroid gland, and to identify the factors that might influence the development of hypothyroidism. Materials and Methods : From September 1986 through December 1994, 71 patients with head and cancer treated with surgery and radiation were included in this prospective study. Patients' age ranged from 32 to 73 years with a median age of 58 years. There were 12 women and 59 men. The primary tumor sites were larynx in 34 patients, hypopharynx in 13 patients, oral cavity in 12 patients, unknown primary of the neck in 6 patients, salivary gland in 3 patients, maxillary sinus in 2 patients, and oropharynx in 1 patient. Total laryngectomy with neck dissection was carried out in 45 patients and neck dissection alone in 26 patients. All patients were serially monitored for thyroid function (T3, T4, free T4, TSH, antithyroglobulin antibody and antimicrosomal antibody) before and after radiation therapy. Radiation dose to the thyroid gland ranged from 40.6Gy to 60Gy with a median dose of 50Gy The follow-up duration was 3 to 80 months. Results :The overall incidence of hypothyroidism was 56.3\%$);7 out of 71 patients $(9.9\%)$ developed clinical hypothyroidism and 33 patients $(46.4\%)$ developed subclinical hypothyroidism. No thyroid nodules, thyroid cancers, or hyperthyroidism was detected. Hypothyroidism developed earlier in patients who underwent total laryngectomy with neck dissection than in patients with neck dissection alone (P<0.05). The risk factor that significantly influenced the incidence of hypothyroidism was a combination of surgery (total laryngectomy with neck dissection) and radiation therapy (P=0.0000), Four of 26 patients $(15.4\%)$ with neck dissection alone developed hypothyroidism while 36 of 45 patients $(80\%)$ with laryngectomy and neck dissection developed hypothyroidism. Conclusion : The hypothyroidism following surgery and radiation therapy was a relatively common complication. The factor that significantly influenced theincidence of hypothyroidism was combination of surgery and radiation therapy. Evaluation of thyroid function before and after radiation therapy with periodic thyroid function tests is recommended for an early detection of hypothyroidism and thyroid hormone replacement therapy is recommended whenever hypothyroidism develops.

• Radiation Oncology Journal
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• v.14 no.1
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• pp.53-59
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• 1996

Purpose : Radiation-induced alteration in the immune function is well known phenomenon in cancer patients. Our purpose is to evaluate the extent of immune suppression immediately after mediastinal or pelvic irradiation, which include significant volume of active bone marrow in adults. Materials and Methods'48 cancer patients with mediastinal(N=29) and pelvic irradiation(N=19) were the basis of this analysis. Age ranged from 36 to 76 and mean and median value was 57 years, respectively Sex ratio was 1.3(M: F=27/21). The immunological parameters were the complete blood cell(CBC) with differential cell(D/C) count, T cell subset(CD3, CD4, CD8 CDl9), NK cell test(CDl6, CD56), and serum immunoglobulin(IgG, IgA, IgM) level. Results : The mean value of white blood cell(WBC) was reduced from 7017 to 4470 after irradiation(p=0.0000). In the differential count, the number of lymphocyte, neutrophil, and basophil was markedly reduced with statistical significance(p<0.01) and the number of monocyte was not changed and, on the contrary, that of eosinophil was increased by irradiation. In the lymphocyte subpopulation analysis, the number of all subpopulations, CD3(T cell), CD4(helper T cell), CD8(suppressor T cell), CDl6(NK cell), CDl9(B, cell) was reduced with statistical significance. The mean ratio of CD4 to CD8 in all patients was 1.09 initially and reduced to 0.99 after radiotherapy(p=0.34) , but the proportional percentage of all subpopulations was not changed except CD19(B cell) after irradiation. In the immunoglobulin study, initial values of Ig G, Ig A, and Ig M were relatively above the normal range and the only Ig M was statistically significantly reduced after radiotherapy(p=0.02). Conclusion : Mediastinal and pelvic irradiation resulted in remarkable suppression of lymphocyte count in contrast to the relatively good preservation of other components of white blood cells. But the further study on the functional changes of lymphocyte after radiotherapy may be necessary to conclude the effects of the radiation on the immunity of the cancer Patients.