• 대한두경부종양학회지
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• 제22권1호
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• pp.23-28
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• 2006

Background and Objectives: Maxillectomy is the mainstay of treatment for malignant tumors of the maxillary sinus(MS). Nevertheless, few have been reported on the surgical outcomes of maxillectomy for malignant tumors of MS in Korean literature. Based on our clinical experience, the authors aimed to present the treatment outcomes of maxillectomy for squamous cell carcinomas(SCC) of MS. Subjects and Methods: We reviewed the medical records of 26 cases of maxillectomies with see of MS, who were treated from 1995 to 2004 at Samsung Medical Center. Most patients(73.1%) were locally advanced stage(T3 or T4a) at initial presentation. Total maxillectomy was performed in 18 cases, which is the most frequent procedure(69.2%). We analyzed the treatment outcomes of see of MS and several variables includeing tumor stage and resection margin to identify predictors for treatment failure after maxillectomy. Follow-up duration ranged from 7 to 89 months with a mean of 33 months. Results: Treatment failure occurred in 7 cases(26.9%), among which 3 were salvaged. Three of 26 maxillectomies(11.5%) showed the positive or close(less than 5mm) resection margin in their posterior resection sites; however it did not coincide with the site of recurrence after radiation therapy. Among patients who had been followed up for more than 6 months, disease-free 3 year survival rate was 100.0% in T1 and T2, 76.2% in T3, 60% in T4a, and 69.6% in total. Conclusion: Even though most of see of MS were detected at locally advanced stage, maxillectomy with or without postoperative radiation therapy for resectable MS see(T1-T4a) provided the acceptable treatment outcome(70%, 3Y disease-free survival rate).

• Radiation Oncology Journal
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• 제37권4호
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• pp.293-301
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• 2019

Purpose: External beam radiotherapy (EBRT) is a useful option to treat head and neck skin cancer patients who are not indicated for surgery. In this study, we evaluated the treatment outcomes of EBRT in an Asian population. Materials and Methods: The records from 19 head and neck skin cancer patients (10 with squamous cell carcinoma and 9 with basal cell carcinoma) who were treated with definitive or adjuvant EBRT from 2009 to 2017 were retrospectively reviewed. The radiotherapy doses administered ranged from 50 to 66 Gy (median, 55 Gy) with 2.0-2.75 Gy per daily fraction (median, 2.5 Gy). The T stage at presentation was as follows: Tis (1 patient), T1 (11 patients), T2 (6 patients), and T3 (1 patient). None had regional lymph node disease or distant metastasis at presentation. The local failure-free survival (LFFS) rates, toxicity, and cosmetic results were analyzed. Results: The median age was 75.5 years (range, 52.6 to 92.5 years). The median follow-up duration from the completion of radiotherapy was 44.9 months (range, 5.8 to 82.6 months). One local failure occurred in a patient with a 2.1-cm posterior neck squamous cell carcinoma at 32.5 months after radiotherapy (1/19, 5.3%). The 3-year LFFS rate was 91.7%. No patients died from skin cancer during follow-up, and no grade 3 complications occurred. The cosmetic outcomes were excellent for 16 (84.2%) and good for 3 (15.8%) of the 19 patients. Conclusion: EBRT offers good local control and cosmetic outcomes in patients with head and neck skin cancer, with no grade 3 complications.

• Asian Pacific Journal of Cancer Prevention
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• 제14권10호
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• pp.5579-5587
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• 2013

Research indicates that a small population of cancer cells is highly tumorigenic, endowed with the capacity for self-renewal, and has the ability to differentiate into cells that constitute the bulk of tumors. These cells are considered the "drivers" of the tumorigenic process in some tumor types, and have been named cancer stem cells (CSC). Epithelial-mesenchymal transition (EMT) appears to be involved in the process leading to the acquisition of stemness by epithelial tumor cells. Through this process, cells acquire an invasive phenotype that may contribute to tumor recurrence and metastasis. CSC have been identified in human head and neck squamous cell carcinomas (HNSCC) using markers such as CD133 and CD44 expression, and aldehyde dehydrogenase (ALDH) activity. Head and neck cancer stem cells reside primarily in perivascular niches in the invasive fronts where endothelial-cell initiated events contribute to their survival and function. Clinically, CSC enrichment has been shown to be enhanced in recurrent disease, treatment failure and metastasis. CSC represent a novel target of study given their slow growth and innate mechanisms conferring treatment resistance. Further understanding of their unique phenotype may reveal potential molecular targets to improve therapeutic and survival outcomes in patients with HNSCC. Here, we discuss the state-of-the-knowledge on the pathobiology of cancer stem cells, with a focus on the impact of these cells on head and neck tumor progression, metastasis and recurrence due to treatment failure.

• 대한기관식도과학회지
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• 제15권1호
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• pp.28-34
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• 2009

Background and Objectives: Foreign bodies of upper aerodigestive tract are common problem for primary care physicians. Delayed diagnosis or failure of removal might cause fatal problemsand complications. Therefore proper diagnosis and management is imperative. In this study, we described clinical features of upper aerodigestive tract foreign body, and analyzed efficacy of different management modality. Materials and Methods: 250 cases of foreign bodies in the esophagus and trachea, between Jan. 1998 through Jan. 2009 has been retrospectively analyzed. A total of 24 cases and 226 cases had been found each as airway foreign bodies and esophageal foreign bodies. The clinical features are described and treatment outcomes, prognosis, and rate of complications of each management modality have been compared. Results: In airway foreign bodies, ventilating bronchoscopy yielded better results, 19 success out of 19 trials than fiberoptic bronchoscopy, 3 success out of 5 trials. Hospitalization days after removal of foreign body didn't show difference between two treatment modalities, although patients who had ventilating bronchoscopy had gone through general anesthesia. And there was no complication after removal of foreign body. In esophageal foreign bodies, rigid esophagoscope yielded better results, 99% of successful removal rate, compared to the EGD, only 78% of successful removal rate. There was no difference of hospitalization days between two modalities. And complication rate was even low in patients who had done rigid esophagoscopic foreign body removal. Conclusion: In upper aerodigestivetract foreign body. Rapid diagnosis and successful foreign body removal is important. Removal by rigid scope(ventilating bronchoscope, rigid esophagoscope) revealed less failure in both airway and esophageal foreign bodies.

• International journal of thyroidology
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• 제11권2호
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• pp.130-136
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• 2018

Background and Objectives: Intraoperative neural monitoring (IONM) of recurrent laryngeal nerve (RLN) in thyroid surgery has been employed worldwide to identify and preserve the nerve as an adjunct to visual identification. The aims of this study was to evaluate the efficacy of IONM and difficulties in the learning curve. Materials and Methods: We studied 63 patients who underwent thyroidectomy with IONM during last 2 years. The standard IONM procedure was performed using NIM 3.0 or C2 Nerve Monitoring System. Patients were divided into two chronological groups based on the success rate of IONM (33 cases in the early period and 30 cases in the late period), and the outcomes were compared between the two groups. Results: Of 63 patients, 32 underwent total thyroidectomy and 31 thyroid lobectomy. Failure of IONM occurred in 9 cases: 8 cases in the early period and 1 case in the late period. Loss of signal occurred in 8 nerves of 82 nerves at risk. The positive predictive value increased from 16.7% in the early period to 50% in the late period. The mean amplitude of the late period was higher than that of the early period (p<0.001). Conclusion: IONM in thyroid surgery is effective to preserve the RLN and to predict postoperative nerve function. However, failure of IONM and high false positive rate can occur in the learning curve, and the learning curve was about 30 cases based on the results of this study.

• Archives of Reconstructive Microsurgery
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• 제8권1호
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• pp.35-43
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• 1999

저자들은 1988년부터 1998년까지 시행한 252예의 유리피판술 중 9예에서 미세혈관 문합부의 혈전 등의 이유로 실패하였으며, 이들 중 두경부 및 하지의 7예에서는 첫 수술 4-16일 사이에 제 2의 유리피판술을 성공적으로 시행하여 환부를 치유시키고, 처음에 계획하였던 수술적 목표를 달성하였다. 수부의 2예는 환자 및 보호자와 충분한 상의하여 원거리 피판과 피부이식 등 고식적인 치료 방법을 선택하였다. 수부의 경우는 다른 부위보다 고식적 치료 방법이 덜 부담되었던 것으로 생각되었으며, 두경부와 하지는 환부의 특성상 제 2의 유리 피판술이 최선의 선택으로 생각되었다. 유리 피판술이 실패한 환부에서 계속된 제 2의 유리 피판술을 시행하는 것은, 처음의 수술보다 면밀한 술전 계획과 준비, 완벽한 수술, 수술후의 철저한 환자 관리가 요구되었으나, 이들 환부의 처치에 매우 효과적이고 환자의 기대에 부응할 수 있는 방법이라고 생각된다.

• 대한두경부종양학회지
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• 제15권2호
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• pp.182-188
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• 1999

Purpose: To investigate the treatment results' and patterns of failure according to the pathologic type of the parotid malignancy who were treated with radical sugery and postoperative radiation therapy. Materials and Methods: Fifty-two patients with various type of the parotid malignancy, who were treated with combined radical surgery and post-operative irradiation at Yonsei Cancer Center, between 1981 and 1995, were retrospectively reviewed after completion treatment, all but one patients were follow up with the median follow up period of 49 months. Results: We found that pathologically confirmed neck node metastasis rate was 28.8% all case and level II was most common site. Overall failure rate was 26.9%, local recurrence rate was 13.5%, node failure rate was 7.7%, and distant failure rate was 5.8%. Five-year disease free survival rate was 70.9%, and overall survival rate was 73.8%. Recurrence rate was low in adenoid cystic carcinoma and acinic cell carcinoma. However distant metastasis was very high in undifferentiated carcinoma. Local recurrence was main pattern of failure in mucoepidermoid carcinoma and nodal failure was frequently observed in adenocarcinoma. Conclusion: Individualized treatment plan may be required to improve a treatment outcome by pathologic subtype of the parotid malignancy.

• 대한두경부종양학회지
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• 제14권2호
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• pp.164-168
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• 1998

레이저를 이용한 내시경하 상후두부분절제술은 술전에 정확한 병기판정으로 초기 국소병변의 선택을 신중하게 하고 경부 림프절전이의 치료를 효율적으로 시행하는 경우 기존의 수술법과 유사한 생존율을 얻을 수 있었다. 환자의 상태에 따라서 충분한 수술시야를 확보하는데 어려움이 있으며, 병변의 위치에 따라서 술중 절제연의 확인이 힘들다는 제한점을 고려해야 하며, 술 후 발생할 수 있는 출혈, 부종, 오연 등의 합병증에 대비하기 위하여 술 전 기관절개술이 유용할 것으로 생각된다.

• 대한두경부종양학회지
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• 제20권2호
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• pp.156-160
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• 2004

Background and Objectives: Neck metastasis is one of the most important prognostic factors in treating tonsillar cancer. Incidence and pattern of lymph node metastasis of tonsillar squamous cell carcinoma are the basic knowledge of treatment decision. Occult metastasis rate of tonsillar cancer and pattern of metastasis, failure pattern, survival were retrospectively analyzed. Patients and Methods: Seventy six patients who underwent surgery for tonsillar squamous cell carcinoma as an initial treatment from 1992 to 2004 were evaluated. Charts, imaging studies and pathologic reports were reviewed. Results: At the time of surgery, 78% of patients with tonsillar cancer had neck metastasis and 66% had multiple node metastasis. Occult neck metastasis was in 26%. There was high incidence of neck metastasis even in early stage of primary lesion. Conclusion: High incidence of lymph node metastasis was confirmed histopathologically in tonsillar cancer. All tonsillar cancer patients may need elective treatment of the neck. Tonsillar cancer had relatively good prognosis even though its neck metastasis rate is very high.

• 한국자동차공학회논문집
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• 제19권5호
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• pp.67-75
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• 2011

A new energy absorbing mechanism for car seat was developed to reduce the neck injury in rear impacts. Energy absorbing principle is based on the shear-bolt behavior of thin-walled cast components subjected to static and dynamic loads. Results of shear bolt test using AM60 of Mg alloys showed robust behavior giving an approximately constant mean force during failure processes. Simply designed energy absorbing mechanism was assembled with the recliner between seat backs and seat rails. We have simulated the sled test of seat with dummy under the rear end impact using the finite element method. Results of simulation show that the new seat mechanism reduces thorax acceleration to a considerable extent, but it is not sufficient to mitigate neck injury indices e.g. neck shear force, neck tension force and NIC. With heightened headrest and narrowed backset, the energy absorbing mechanism resulted in good performance of protecting the neck injuries.