• Radiation Oncology Journal
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• v.16 no.4
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• pp.399-408
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• 1998

Purpose : This study was designed to demonstrate the potential therapeutic advantage of 3-dimensional (3-D) treatment planning over the conventional 2-dimensional (2-D) approach in patients with carcinoma of the nasopharynx. Materials and Methods : The two techniques were compared both qualitatively and quantitatively for the boost portion of the treatment (19.8 Gy of a total 70.2 Gy treatment schedule) in patient with T4. The comparisons between 2-D and 3-D plans were made using dose statistics, dose-volume histogram, tumor control probabilities, and normal tissue complication probabilities. Results : The 3-D treatment planning improved the dose homogeneity in the planning target volume. In addition, it caused the mean dose of the planning target volume to increase by 15.2$\%$ over 2-D planning. The mean dose to normal structures such as the temporal lobe, brain stem, parotid gland, and temporomandibular joint was reduced with the 3-D plan. The probability of tumor control was increased by 6$\%$ with 3-D treatment planning compared to the 2-D planning, while the probability of normal tissue complication was reduced. Conclusion : This study demonstrated the potential advantage of increasing the tumor control by using 3-D planning. but prospective studies are required to define the true clinical benefit.

• Radiation Oncology Journal
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• v.23 no.1
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• pp.1-8
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• 2005

Purpose : The objective of this study was to determine whether the expressions of the two components of DNA-dependent protein kinase, Ku70 and DNA-PKcs, influence the response to radiotherapy (RT) and outcome of treatment of non-disseminated nasopharyngeal carcinoma (NPC) in patients who received definitive RT. Materials and Methods : Sixty-six patients with NPC who were treated with radiotherapy alone or with concurrent chemotherapy between June 1995 and December 2001 were divided into groups based on the levels of immunoreactivity for Ku70 and DNA-PKcs in pretreatment biopsy specimens. The over-expression of Ku70 or DNA-PKcs groups Included patients whose biopsy specimens showed at least 50% immunopositive tumor cells; patients in which less than 50% of the tumor cells in the biopsy tissues were immunopositive were placed in the low Ku70 and DNA-PKcs groups. The immunoreactivities for Ku70 and DNA-PKcs were retrospectively compared with the sensitivity of the tumor to radiation and the patterns of therapy failure. Univariate analyses were peformed to determine the prognostic factors that influenced locoregional control of NPC. Results : The five-year locoregional control rate was significantly higher in the low Ku70 group (Ku(-)) (85%) than in the high Ku70 group (Ku(+)) (42%) (p=0.0042). However, there were no differences in the metastases-free survival rates between the two groups (Ku70 (+), 82%; Ku70 (-), 78%; p=0.8672). Univariate analysis indicated that the over-expression of Ku70 surpassed other well-known predictive clinocopathologic parameters as an Independent prognostic factor for locoregionai control. Eighteen of 22 patients who had locoregional recurrences of the tumor displayed an over-expression of Ku70. No significant association was found between the level of DNA-PKcs expression and the clinical outcome. Conclusion : Our data suggest that the level of Ku70 expression can be used as a molecular marker to predict the response to RT and the locoregional control after RT and concurrent chemotherapy in patients with non-disseminated NPC.

• The Journal of Korean Society for Radiation Therapy
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• v.33
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• pp.127-135
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• 2021

Purpose : The purpose of the study is to evaluate the efficiency of Vertical MLC VMAT plan(VMV plan) Using 273° and 350° collimator angle compare to Complemental MLC VMAT plan(CMV plan) using 20° and 340° collimator angle for nasopharyngeal carcinoma. Materials & Methods : Thirty patients treated for nasopharyngeal carcinoma with the VMAT technique were retrospectively selected. Those cases were planned by Eclipse, PO and AcurosXB Algorithm with two 6MV 360° arcs and Each arc has 273° and 350° of collimator angle. The Complemental MLC VMAT plans are based on existing treatment plans. Those plans have the same parameters of existing treatment plans but collimator angle. For dosimetric evaluation, the dose-volumetric(DV) parameters of the planning target volume (PTV) and organs at risk (OARs) were calculated for all VMAT plans. MCSv(Modulation complexity score of VMAT), MU and treatment time were also compared. In addition, Pearson's correlation analysis was performed to confirm whether there was a correlation between the difference in the MCSv and the difference in each evaluation index of the two treatment plans. Result : In the case of PTV evaluation index, the CI of PTV_67.5 was improved by 3.76% in the VMV Plan, then for OAR, the dose reduction effect of the spinal cord (-14.05%) and brain stem (-9.34%) was remarkable. In addition, the parotid glands (left parotid : -5.38%, right : -5.97%) and visual organs (left optic nerve: -4.88%, right optic nerve: -5.80%, optic chiasm : -6.12%, left lens: -6.12%, right lens: -5.26%), auditory organs (left: -11.74%, right: -12.31%) and thyroid gland (-2.02%) were also confirmed. The difference in MCSv of the two treatment plans showed a significant negative (-) correlation with the difference in CI (r=-0.55) of PTV_54 and the difference in CI (r=-0.43) of PTV_48. Spinal cord (r=0.40), brain stem (r=0.34), and both salivary glands (left: r=0.36, right: r=0.37) showed a positive (+) correlation. (For all the values, p<.05) Conclusion : Compared to the CMV plan, the VMV plan is considered to be helpful in improving the quality of the treatment plan by allowing the MLC to be modulated more efficiently

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.12
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• pp.7433-7438
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• 2013

Aim: To identify new biomarkers for NPC diagnosis with an anti-EBV Western blot test kit. Methods: Serum samples from 64 NPC patients and healthy subjects with four specific VCA-IgA/EA-IgA profiles were tested with an anti-EBV Western blot test kit from EUROIMMUN AG. Proteins were quantified with scores of intensity visually assigned to the protein bands. The markers which showed statistical differences between the NPC and non-NPC subjects were further evaluated in another 32 NPC patients and 32 controls in comparison with established biomarkers including VCA-IgA, EA-IgA, EBV-related protein IgG, and EBV DNA. Results: Among the markers screened, EA-D p45-IgG showed a statistically significant difference (p < 0.05) between NPC and non-NPC subjects with VCA-IgA positivy. In 32 VCA-IgA positive NPC patients and 32 control subjects, the diagnostic accuracy of EA-D p45-IgG was 78.1% with a positive predictive value of 77.8% and a negative predictive value of 78.6%. In the verification experiment, the specificity and sensitivity of EA-D p45-IgG were 75.0% and 90.6 %, respectively. Conclusions: EA-D p45-IgG might be a potential biomarker for NPC diagnosis, especially among VCA-IgA positive subjects.

• Korean Journal of Bronchoesophagology
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• v.4 no.1
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• pp.52-58
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• 1998

BACKGROUND： Aspiration is defined as the laryngeal penetration of secretions below the level of the true vocal cords. Aspiration can result in life-threatening complications, such as bronchospasm, airway obstruction, pneumonia, pulmonary abscess, sepsis, and death. The patient with high vagal palsy had significant aspiration and dysphagia OBJECTIVE： To formulate a step-by-step management paradign for the patients with high vagal palsy MATERIALS AND METHODS : The medical records of 23 patients who were diagnosed as high vagal palsy from September, 1995 to April, 1998 in Seoul National University Hospital were reviewed retrospectively. Eleven patients were managed conservatively and 12 patients were operated to treat chronic aspiration. RESULTS : The main etiologies of high vagal palsy were mass lesions of the skull base such as neurogenic tumor, pseudotumor, meningioma or nasopharyngeal carcinoma. Aspiration and dysphagia improved in 7 out of 11 patients who were managed conservatively after 2.2 months on the average. The patients who were refractory to the conservative management underwent surgery and showed improvement in 10 out of 12 patients. The employed surgical modalities were vocal cord medialization combined with cricopharyngeal myotomy in 7 patients, laryngotracheal separation in 3 patients and arytenoid adduction only in 2 patients. Two patients still had gastrostomy tube due to the persistent symptoms. Two patients had improved after surgery, but died of underlying disease. CONCLUSION : The patients with high vagal palsy are recommended to be managed conservatively for the first 2 months. If aspiration and dysphagia are persisting after conservative management, vocal cord medialization combined with or without cricopharyngeal myotomy should be considered. If failed, laryngotracheal separation or gastrostomy will be the next option based on the control of the oropharyngeal secretion.

• The Journal of Korean Society for Radiation Therapy
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• v.22 no.2
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• pp.105-111
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• 2010

Purpose: There are various beam parameter in intensity modulated radiation therapy (IMRT). The aim of this study is to investigate how various dose rate affect the parotid in treatment plan of IMRT. Materials and Methods: The study was performed on 10 nasopharyngeal carcinoma patients who have undergone IMRT. CT images were scanned 3 mm of thickness in the same condition and the treatment plan was performed by Eclipse (Ver.7.1, Varian, Palo Alto, USA). The parameters for planning used 6 MV energy and 8 beams under the same dose volume constraint. The variation of dose rates were used 300, 400, 500 MU/min. The mean dose of both parotid was accessed from the calculated planning among the 10 patients. The mean dose of parotid was verificated by 2D diode array (Mapcheck from Sun Nuclear Corporation, Melbourne, Florida). Also, Total monitor unit (MU) and beam-on time was analysed. Results: According to the dose rate, the mean dose of parotid was increased by 0.8%, 2.0% each, when dose rate was changed from 300 MU/min to 400, 500 MU/min, moreover Total MU was increased by 5.4% and 10.6% each. There was also a dose upward trend in the dose measurement of parotid by 2D diode array. However, beam - on time difference of 1~2 minutes was no signigicant in the dose rate increases. Conclusion: From this study, when the dose rates increase, there was a signigicant increase of Total MU and the parotid dose accordingly, however the shortened treatment time was not significant. Hence, it is considered that there is a significant decrease of late side effect in parotid radiation therapy, if the precise dose rate in IMRT is used.

• Journal of Preventive Medicine and Public Health
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• v.27 no.2 s.46
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• pp.217-225
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• 1994

The relationship between past liver disease history and the risk of primary liver cancer was analyzed in a hospital-based case-control study conducted in Seoul on 165 patients with histologically or serologically confirmed hepatocellular carcinoma and individually age- and sex-matched 165 controls in hospital for ophthalmologic, otologic, or nasopharyngeal problems. Significant association were observed for liver deseases occurring 5 or more years before liver cancer diagnosis [OR,4.9;95% confidence interval (CI), $1.6{\sim}14.0$) and family history of liver disease(OR, 9.0;95% CI, $2.1{\sim}38.8$). These associations were not appreciably modified by allowance for major identified potential confounding factors. From these results, it is possible to speculate that liver cell injuries caused by various factors might be a common pathway to developing primary liver carcinoma. Considering the significant effect of family history of liver diseases on PLCA risk after adjusting past liver disease history, there might be genetic susceptibility in the carcinogenic mechanism of liver cancer. Further investigations are needed to clarify the effect of family history of liver disease on PLCA risk.

• The Journal of Korean Society for Radiation Therapy
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• v.25 no.1
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• pp.1-8
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• 2013

Purpose: A selection of proper energy in treatment planning is very important because of having different dose distribution in body as photon energy. In generally, the low energy photon has been used in intensity-modulated radiation therapy (IMRT) for head and neck (H&N) cancer. The aim of this study was to evaluate the effect of partially used high energy photon at posterior oblique fields on IMRT plan for H&N cancer. Materials and Methods: The study was carried out on 10 patients (nasopharyngeal cancer 5, tonsilar cancer 5) treated with IMRT in Seoul National University Bundang Hospital. CT images were acquired 3 mm of thickness in the same condition and the treatment plan was performed by Eclipse (Ver.7.1, Varian, Palo Alto, USA). Two plans were generated under same planing objectives, dose volume constraints, and eight fields setting: (1) The low energy plan (LEP) created using 6 MV beam alone, (2) the partially used high energy plan (PHEP) created partially using 15 MV beam at two posterior oblique fields with deeper penetration depths, while 6 MV beam was used at the rest of fields. The plans for LEP and PHEP were compared in terms of coverage, conformity index (CI) and homogeneity index (HI) for planning target volume (PTV). For organs at risk (OARs), $D_{mean}$ and $D_{50%}$ were analyzed on both parotid glands and $D_{max}$, $D_{1%}$ for spinal cord were analyzed. Integral dose (ID) and total monitor unit (MU) were compared as addition parameters. For the comparing dose to normal tissue of posterior neck, the posterior-normal tissue volume (P-NTV) was set on the patients respectively. The $D_{mean}$, $V_{20Gy}$ and $V_{25Gy}$ for P-NTV were evaluated by using dose volume histogram (DVH). Results: The dose distributions were similar with regard to coverage, CI and HI for PTV between the LEP and PHEP. No evident difference was observed in the spinal cord. However, the $D_{mean}$, $D_{50%}$ for both parotid gland were slightly reduced by 0.6%, 0.7% in PHEP. The ID was reduced by 1.1% in PHEP, and total MU for PHEP was 1.8% lower than that for LEP. In the P-NTV, the $D_{mean}$, $V_{20Gy}$ and $V_{25Gy}$ of the PHEP were 1.6%, 1.8% and 2.9% lower than those of LEP. Conclusion: Dose to some OARs and a normal tissue, total monitor unit were reduced in IMRT plan with partially used high energy photon. Although these reduction are unclear how have a clinical benefit to patient, application of the partially used high energy photon could improve the overall plan quality of IMRT for head and neck cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.11
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• pp.4697-4703
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• 2014

Background: Interleukin-16 (IL-16) is a multifunctional cytokine which plays a key role in inflammatory and autoimmune diseases as well as in cancer. Genetic polymorphisms of IL-16 have been implicated in susceptibility to cancer. However, associations remain inconclusive. The present meta-analysis was therefore carried out to establish a more conclusive association of IL-16 polymorphisms with cancer risk. Materials and Methods: Relevant studies were searched through the PubMed, Embase, Web of Science, Google Scholar and Wan fang electronic databases updated in October 2013. Odds ratios (OR) and 95% confidence intervals (95% CI) were used to assess the association between IL-16 polymorphisms and cancer risk. Results: Eight eligible studies (rs4778889 T/C: 8, rs11556218 T/G: 7, rs4072111 C/T: 6) that met our selection criteria were included. The meta-analysis indicated that rs11556218 T/G was associated with a significant increased risk of cancer (G vs. T, OR=1.321, 95% CI=1.142-1.528, P<0.001; TG vs. TT, OR=1.665, 95% CI=1.448-1.915, P<0.001; GG+TG vs. TT, OR=1.622, 95% CI=1.416-1.858, P<0.001),as well as nasopharyngeal carcinoma and colorectal cancer. Furthermore, in the subgroup of Chinese, significant associations were found between rs11556218 polymorphism and cancer risk. There was no statistically significant association between the other two variants (rs4778889, rs4072111) and risk of cancer. Conclusions: This meta-analysis suggests that the IL-16 rs11556218 polymorphism is associated with increased cancer risk. Large well-designed studies involving various cancer types and different populations are now needed.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.14
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• pp.5557-5563
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• 2014

Background: This study investigated the survival benefit of radiotherapy (RT) of the supra- and infraclavicular lymphatic drainage area in Chinese women with T1-2N1M0 breast cancer receiving mastectomy. Methods: A total of 593 cases were retrospectively reviewed from 1998 to 2007. The relationship between supra- or infraclavicular fossa relapse (SCFR) and post-operative RT at the supra-/infraclavicular lymphatic drainage area was evaluated. Results: The majority of patients (532/593; 89. 8%) received no RT while 61 patients received RT. The median follow-up was 85 months. Among patients without RT, 54 (10. 2%) developed recurrence in the chest wall or ipsilateral SCFR. However, none of the 61 patients who underwent RT demonstrated SCFR. One patient who received RT (1. 6%) experienced recurrence in the chest wall. Univariate analysis revealed that age and molecular subtype (both P < 0. 05) were two prognostic factors related to supraclavicular and infraclavicular fossa relapse-free survival (SFRFS). Multivariate analysis revealed that only Her-2 positive status (P = 0. 011) was an independent predictor of SFRFS. RT had no influence on distant metastasis (P = 0. 328) or overall survival (P = 0. 541). SCFR significantly affected probability of distant metastasis (P < 0. 001) and overall survival (P < 0. 001). Conclusion: Although RT was not significantly associated with SFRFS, postoperative RT was significantly associated with a lower locoregional (i. e., supraclavicular/infraclavicular and chest wall) recurrence rate. SCFR significantly influenced distant metastasis-free survival, which significantly influenced the overall survival of T1-2N1M0 breast cancer patients after mastectomy. Thus, prophylactic RT is recommended in T1-2N1M0 breast cancer patients, especially those who have Her-2 positive lesions.