• Journal of Radiation Protection and Research
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• v.40 no.1
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• pp.17-24
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• 2015

To improve accuracy of dose calculation on kilovoltage cone beam computed tomography (kV CBCT) images, a custom-made phantom was fabricated to acquire an accurate CT number to electron density curve by full scatter of cone beam x-ray. To evaluate the dosimetric accuracy, 9 volumetric modulated arc therapy (VMAT) plans for head and neck (HN) cancer and 9 VMAT plans for lung cancer were generated with an anthropomorphic phantom. Both CT and CBCT images of the anthropomorphic phantom were acquired and dose-volumetric parameters on the CT images with CT density curve (CTCT), CBCT images with CT density curve ($CBCT_{CT}$) and CBCT images with CBCT density curve ($CBCT_{CBCT}$) were calculated for each VMAT plan. The differences between $CT_{CT}$ vs. $CBCT_{CT}$ were similar to those between $CT_{CT}$ vs. $CBCT_{CBCT}$ for HN VMAT plans. However, the differences between $CT_{CT}$ vs. $CBCT_{CT}$ were larger than those between $CT_{CT}$ vs. $CBCT_{CBCT}$ for lung VMAT plans. Especially, the differences in $D_{98%}$ and $D_{95%}$ of lung target volume were statistically significant (4.7% vs. 0.8% with p = 0.033 for $D_{98%}$ and 4.8% vs. 0.5% with p = 0.030 for $D_{95%}$). In order to calculate dose distributions accurately on the CBCT images, CBCT density curve generated with full scatter condition should be used especially for dose calculations in the region of large inhomogeneity.

• Journal of Yeungnam Medical Science
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• v.37 no.4
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• pp.302-307
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• 2020

Background: This study evaluated the usefulness of judgment of central lymph node (LN) metastasis by surgeon's palpation in papillary thyroid cancer. Methods: This study included 127 patients who underwent thyroidectomy and central compartment node dissection between October 2014 and February 2015. The criterion for suspicious LNs was hardness. Results: Of the 20.5% (28/127) of suspicious for metastatic LNs according to surgeon determination, 92.8% (26/28) were confirmed to be metastatic in the final pathological examinations. Metastatic LNs were found in 38 (38.3%) of 99 patients without suspicious LNs, 29 of whom (76.3%) had micrometastases. The sensitivity, specificity, and positive and negative predictive values for the determination of LN metastasis by a surgeon were 40.6%, 96.8%, 92.9%, and 61.6%, respectively. Conclusion: Determination of central LN metastasis by a surgeon's palpation may be useful to evaluate LNs owing to the high specificity and positive predictive values, especially in macrometastasis or high-risk LN disease.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.8
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• pp.3961-3965
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• 2012

Objective: To compare the clinical effects of concurrent radiochemotherapy with those of radiotherapy in treating locally advanced nasopharyngeal carcinoma (Stage III~IVa). Methods: A total of 95 patients suffering from nasopharyngeal carcinoma (Stage III~IVa) were divided into two groups: concurrent radiochemotherapy (Group CCRT, n=49) and radiotherapy (Group RT, n=46). The two groups were both delivered conventional fractionated radiotherapy, while Group CCRT also received three cycles of PF (DDP+5-Fu) or PLF (DDP+5-Fu+CF) chemotherapy. Results: The complete remission rate and total remission rate of Group CCRT were higher than those of Group RT ($X^2$=4.72~7.19, P<0.05). The one-year overall survival (OS) rate calculated by the life table method, was also higher than that of Group RT ($X^2$=4.24, P<0.05) as well as the 3-year OS rate, nasopharyngeal control rate and cervical lymph nodes' control rate ($X^2$=4.28~4.40, P<0.05). In addition, the 5-year OS and metastasis-free rates of Group CCRT were higher than those of Group RT and the differences were of statistical importance ($X^2$=3.96~8.26, P<0.05). However, acute toxicity was also obviously higher, the difference in gastrointestinal reactions being statistically significant ($X^2$=11.70, P<0.05). Conclusion: This study demonstrated that concurrent radiochemotherapy could improve the remission rate, overall survival rate and locally control rate. The toxicity of concurrent radiochemotherapy could be tolerated by the patients.

• Journal of Oral Medicine and Pain
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• v.33 no.4
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• pp.395-399
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• 2008

Orofacial pain and limited range of mouth opening as symptoms of temporomandibular disorder are mainly triggered by the structural and/or functional changes of temporomandibular joint and related structure itself. But careful diagnostic evaluation should be needed because they may be occurred by another pathologic conditions such as neoplasm in head and neck region. If there would be atypical pain characteristics or clinical features, systemic comorbid symptoms, or poor response to treatment, advanced imaging modalities such as CT or MRI will be mandatory for differential diagnosis. We experienced the case which was diagnosed as nasopharyngeal cancer mimicking temporomandibular disorder, and reviewed clinical considerations for proper differential diagnosis.

• Imaging Science in Dentistry
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• v.36 no.3
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• pp.169-175
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• 2006

The Inflammatory myofibroblastic tumor (inflammatory pseudotumor) is a rarely occurring soft tissue lesion of unknown etiology. It can be of any location, but commonly it is found in lungs. It has been considered as a nonneoplastic reactive inflammatory lesion, but nowadays, confusion and dispute about its character is increasing due to its high recurrence rate and metastasis. We present a patient who had been diagnosed with an inflammatory pseudotumor in the right maxilla area, 1 year before visiting our hospital. After that, her pain and swelling did not resolved and she visit our hospital. On radiographic examination, aggressively infiltrative growth of the lesion with destruction of adjacent bony structure was noted. We found unusual aggressiveness of the inflammatory myofibroblastic tumor of the head and neck region. Because the typical behavior of the inflammatory myofibroblastic tumor is not defined yet, we recommend the surgical excision of the lesion and close follow-up.

• Proceedings of the Korea Information Processing Society Conference
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• 2012.11a
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• pp.450-451
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• 2012

The need of Clinical Decision Support System (CDSS) in healthcare setup is increasing day by day. EHR Meaningful Use advocates CDSS as an important component of EHR/EMR systems. CDSS can be ranged from a simple to a very sophisticated system. The more complex CDSS systems need more attention to develop because of many reasons including its Knowledge Base (KB) structure/maintenance/evolution, inference capabilities and usability. Above all the KB maintenance and evolution is very crucial and important from the perspective of useful decision capabilities. Also the richness of the KB is important to cover the decision gaps handling a particular situation in the course of patient care. It cannot be expected from the clinicians to remember everything in regard to patient diagnosis and treatment. Similarly, it is also crucial for clinicians to keep themselves updated with the new research in the area. That is the reason they frequently require accessing to the online knowledge resources. Literature proved that online knowledge resources are capable providing answers to questions that might not be answered rely only on clinician wisdom and experience. This paper provides the theme of meaningful utilization of online knowledge resources in the context of diagnosis and treatment process for cancer patients more specifically Head and Neck cancer.

• Applied Microscopy
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• v.24 no.1
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• pp.28-40
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• 1994

Xerostomia and xerophthalmia are delicate or serous side effects, occuring when the radiotherapy is administered to the head and neck cancer patient. It is known that the cause of the above side effect is radiosensitivity of serous cells. In this study, the ultrastructural features of the parotid glands of the X-irradiated rats were observed. Sprague-Dawley rats weighing 200-250g each were anesthetized with sodium thiopental, and placed on the Mitsubishi linear accelerator. Only the head and neck areas of animals were exposured at the distance of 80cm, within the area of $30X30cm$, in the depth of 1cm, with the speed of 200R/min. Total doses applied were 3,000R or 6,000R depending on the experimental groups. Animals were sacrificed on the 6th hour, 2nd day and 6th day after the irradiation. Parotid glands were fixed in the 2.5% glutaraldehyde-1.5% paraformaldehyde solution, and followed by refixation in the 1% osmium tetroxide solution. Dehydrated blocks were embedded in araldite mixture, and ultrathin sections were cut. Sections were contrasted with the solution of uranyl acetate and lead citrate, and observed with JEM 100 CX-II electron microscope. The results were as follows: 1. Normal parotid acinar cells are two types; the light and the dark acinar cells. The light acinar cell contains dense secretory granules, whereas dark acinar cells contains granules of medium density with some darker spots within them, or other cells contain granules of medium density with darker rims. 2. Six hours after the irradiation, many acinar cells were degenerated showing variable stages of cytolytic bodies, light bodies, or dense degenerations. Within the acinar cell, Golgi apparatus and granular endoplasmic reticula were most severely altered elements. Granules showed more contrasting densities and irregularities. 3. Two days after the irradiation, some cytolytic bodies, and focal lucent degeneration of cytoplasm, and fine granular alteration of cytoplasmic matrix were pronounced. But other elements including secretory granules are rather looked unlatered. 4. Six days after the irradiation, most severe alterations were seen. Many intracellular canaliculi (or secretion figures), quanta of cytoplasm containing secretion antecedants, severely irregular luminal border, and again contrasting density of secretory granules showing tigroid spots or dense rims were noted. And myoepithelial degenerations were observed not uncommonly. 5. Irregular densities of secretory granules were interpreted as abnormal components of protein or carbohydrate portion are synthesized or abnormally metabolized under severe X-irradiation. 6. Myoepithelial degeneration and related alteration of nerve endings, etc., were suggested as the other causes of xerostomia following X-irradiation. 7. It is requested that radiation doses should be arranged, considering in mind not only the sensitivity of acinar cells but also the myoepithelial and neural functions.

• Korean Journal of Head & Neck Oncology
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• v.14 no.2
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• pp.228-235
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• 1998

Objectives: Papillary microcarcinoma of the thyroid was evaluated as to the effectiveness of diagnostic modalities, lymphatic spread pattern, and therapeutic decision according to tumor size. Material and Methods: We retrospectively analyzed a clinicopathologic findings of 72 papillary microcarcinoma patients who were treated at the over 11 years between 1985 and 1995. The authors divided papillary microcarcinoma of the thyroid into two subgroups according to tumor size: $0{\leqq}5mm$ and $5<0{\leqq}10mm$. An analysis including age and gender distribution, diagnostic tools(thyroid sonogram, thyroid scan, thyroid function test, fine needle aspiration cytology, frozen section), pathological examination of lymphnode, and surgical procedures was carried out in each subgroups. Results: The carcinoma of smaller than 5mm were found in 32 patients, and of 6 -10mm were in 40 patients. The average age of patients was 45years and all of them were female. Cold nodules on thyroid scan were noticed in 53 patientss and normal findings were in 15 patients. Suspicious malignant lesions(fine calcification, solid mass, irregular margin) on thyroid sonography were detected in 23 patients and the sonography was more useful in detecting $0{\leqq}5mm$ small sized lesions than other diagnostic methods. FNAC were performed in 17 patients, and 7 patients were diagnosed as having thyroid papillary cancer. But diagnotic rate in $0{\leqq}5mm$ small sized lesions was very low(one of eights).Frozen section were performed in all patients, among these 15 patients were diagnosed as being benign diseases and false negative rates were higher in $0{\leqq}5mm$ small sized lesions than in $5<0{\leqq}10mm$ sized lesions(p-value<0.006). Only thyroidectomies were performed in 24 patients and thyroidectomy with node dissections in 48 patients. The lymphnode metastatic rates were much higher in multifocal lesions(61.5%) than in single lesion. The incidence of cervical lymphnode metastasis was 19.4% in $0{\leqq}5mm$ sized lesions and 47.9% in $5<0{\leqq}10mm$ sized lesions. Postoperative management were performed with TSH suppression therapy(T4, synthroid) in all patients and RI therapy in 29 patients. Conclusion: On the basis of our study, improved preoperative diagnostic tools for papillary microcarcinoma of the thyroid was helpful in the choice of surgical treatment. As a result of techninological progress(ultrasonography, FNAC), the pencentage of the discovery of papillary microcarcinoma has been increased. The thyroid ultrasonography was useful in detecting small sized lesions($0{\leqq}5mm$), but FNAC may not be beneficial in detecting small sized lesions($0{\leqq}5mm$). In the surgical procedure, thyroid lobectomy alone should be avoided because of the high rate of bilaterality and multifocality.

• Archives of Craniofacial Surgery
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• v.17 no.2
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• pp.56-62
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• 2016

Background: The two most common skin cancers are basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). The purpose of this study was to describe the detailed clinical behavior of BCC and SCC in the head and neck region over 19 years at a single institution. Methods: A retrospective analysis was performed for all patients with non-melanoma skin cancer who had undergone surgical resection over an 18-year period. Patient charts were reviewed for demographic information, tumor size, onset-to-diagnosis, anatomic location, clinical subtype, histologic differentiation, method of surgical treatment, and recurrence. Results: The review identified 265 cases of either BCC or SCC in 226 patients. Of the 226 patients, 80 (35.4%) were men and 146 (64.6%) were women. BCC (n=138, 55.9%) was more frequent than SCC (109, 44.1%). The most frequent age group was 70-to-79 year olds (45 patients, 35.2%) for BCC and 80-to-89 year olds (41 patients, 41.8%) for SCC. By aesthetic units of the face, the most common location was the nasal unit (44 cases, 31.9%) for BCC and the buccal unit (23 cases, 21.1%) for SCC. The most common clinical subtype of BCC was the nodular type (80 cases, 58.0%). Local flaps were most commonly used to cover surgical defects (136 cases, 55.1%). Recurrent rates were 2.2% for BCC and 5.5% for SCC. Conclusion: In our study, many characteristics of BCC and SCC were compared to previously published reports were generally similar, except the ratio of BCC to SCC. Further study can help to establish the characteristics of BCC and SCC.

• Radiation Oncology Journal
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• v.5 no.2
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• pp.149-155
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• 1987

The success of radioation therapy depends on exact treatment of the tumor with significant high dose for maximizing local control and excluding the normal tissues for minimizing unwanted complications. To achieve these goals, correct estimation of target volume in three dimension, exact dose distribution in tumor and normal critical structures and correction of tissue inhomogeneity are required. The effect of therapy oriented CT (plannng CT) were compared with conventional simulation method in necessity of planning change, set dose, and proper distribution of tumor dose. Of 365 new patients examined, planning CT was performed in 104 patients $(28\%)$. Treatment planning was changed in $47\%$ of head and neck tumor, $79\%$ of intrathoracic tumor and $63\%$ of abdmonial tumor. in breast cancer and musculoskeletal tumors, planning CT was recommended for selection of adequate energy and calculation of exact dose to critical structures such as kidney or spinal cord. The average difference of tumor doses between CT planning and conventional simulation was $10\%$ in intrathoracic and intra-abdominal tumors but $20\%$ in head and neck tumors which suggested that tumor dose may be overestimated in conventional simulation Although some limitations and disadvantages including the cost and irradiation during CT are still criticizing, our study showed that CT Planning is very helpful in radiotherapy Planning.