• Korean Journal of Head & Neck Oncology
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• v.16 no.1
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• pp.58-63
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• 2000

Objectives: To demonstrate effective diagnostic method and proper management of recurrent thyroid cancer through to compare treatment and surveillance of $I^{131}$ scanning detected recurrence and clinically detected recurrence. Material and Methods: We retrospectively analyzed clinical information about 46 patients who has recurrent thyroid cancer of 298 patients who have been primarily operated due to thyroid cancer in PMC at the over 10 years between 1986 and 1995. We examine incidence of recurrence due to pathologic types, site of recurrence, disease free interval, detection method of recurrence, and also treatment and progression of recurrence. A patients in which the clinical examination was entirely negative and the $I^{131}$ scan demonstrated either a new area of $I^{131}$ uptake or an increased area of concentration, compared to the previous scan, was designated as a recurrence detected by $I^{131}$ scan only. Recurrences that were obviously by physical examination or chest x-ray, etc were considered clinically detected recurrence, regardless of the the results of the thyroid scan. Results: Mean of disease tree interval(DFI) is 36months. When mean DFI of $I^{131}$ scan detected recurrence is 28months, whereas mean DFI of clinically detected recurrence is 47months. In statiscal analysis, p-value is 0.043 as significantly. In progression of recurrent patient, NED is 28case, AWD is Sease, DOD is 13case. Among the 13case, scan detected recurrence is lease of 20 patients(5%), whereas clinically detected recurrence is l2case of 26 patient(46%). In statiscal analysis, p-value is 0.003 as significantly. Conclusion: Early detection of the recurrent thyroid cancer by $I^{131}$ scanning leads to good progress compare with detection by clinical examination. NED: No Evidence of Disease AWD : Alive With Disease DOD : Dead Of Disease DOC: Dead of Other Cause

• Journal of Korean Neurosurgical Society
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• v.58 no.5
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• pp.426-431
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• 2015

Objective : The purpose of this study was to evaluate the clinical efficacy of continuous low-dose temozolomide (TMZ) chemotherapy for recurrent and TMZ-refractory glioblastoma multiforme (GBM) and to study the relationship between its efficacy and microvessel density within the tumor. Methods : Thirty patients who had recurrent GBM following Stupp's regimen received TMZ daily at $50mg/m^2/day$ until tumor progression between 2007 and 2013. The median duration of continuous low-dose TMZ administration was 8 weeks (range, 2-64). Results : The median progression-free survival (PFS) of continuous low-dose TMZ therapy was 2 months (range, 0.5-16). At 6 months, PFS was 20%. The median overall survival (OS) from the start of this therapy to death was 6 months (95% CI : 5.1-6.9). Microvessel density of recurrent tumor tissues obtained by reoperation of 17 patients was $22.7{\pm}24.1/mm^2$ (mean${\pm}$standard deviation), and this was lower than that of the initial tumor ($61.4{\pm}32.7/mm^2$) (p-value=0.001). It suggests that standard TMZ-chemoradiotherapy reduces the microvessel density within GBM and that recurrences develop in tumor cells with low metabolic burden. The efficacy of continuous low-dose TMZ could not be expected in recurrent GBM cells in poor angiogenic environments. Conclusion : The efficacy of continuous low-dose TMZ chemotherapy is marginal. This study suggests the need to develop further treatment strategies for recurrent and TMZ-refractory GBM.

• The Journal of the Korea Contents Association
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• v.9 no.2
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• pp.97-105
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• 2009

This paper presents a combination of the generalized Cascade Correlation and generalized Recurrent Cascade Correlation learning algorithms. The new network will be able to grow with vertical or horizontal direction and with recurrent or without recurrent units for the quick solution of the pattern classification problem. The proposed algorithm was tested learning capability with the sigmoidal activation function and hyperbolic tangent activation function on the contact lens and balance scale standard benchmark problems. And results are compared with those obtained with Cascade Correlation and Recurrent Cascade Correlation algorithms. By the learning the new network was composed with the minimal number of the created hidden units and shows quick learning speed. Consequently it will be able to improve a learning capability.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2017.11a
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• pp.50-53
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• 2017

Not only growth of importance to understanding economic trends, but also the prediction to overcome the uncertainty is coming up for long-term maritime recession. This paper discussed about the prediction of BDI with artificial neural networks (ANN). ANN is one of emerging applications that can be the finest solution to the knotty problems that may not easy to achieve by humankind. Proposed a prediction by implementing neural networks that have recurrent architecture which are a Recurrent Neural Network (RNN) and Long Short-Term Memory (LSTM). And for the reason of comparison, trained Multi Layer Perceptron (MLP) from 2009.04.01 to 2017.07.31. Also made a comparison with conventional statistics, prediction tools; ARIMA. As a result, recurrent net, especially RNN outperformed and also could discover the applicability of LSTM to specific time-series (BDI).

• Archives of Craniofacial Surgery
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• v.21 no.1
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• pp.27-34
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• 2020

Background: Free-flap reconstruction for recurrent head and neck cancer may be challenging depending on the previous treatments, those are, chemotherapy, radiotherapy, and surgery, including neck dissection or free tissue transfer. Specifically, the previous treatment could compromise the neck vessels, thereby making free-flap reconstruction more difficult. This study aimed to investigate the correlation between previous treatments and vascular compromise of the free flap. Methods: In this retrospective study, 124 free-flap reconstructions in 116 patients for recurrent head and neck cancer between 1993 and 2017 were investigated. The demographic characteristics, previous treatments, flap choices, infections, recipient vessels, and vascular crises were evaluated. Results: Of the 124 reconstruction cases, 10 had vascular crises. There were six revisions, totaling six flap failures. The success rate of free-flap reconstruction for recurrent cancer was 95.2%, which significantly differed from that for primary cancer (98.8%, p= 0.006). Moreover, in the recurrent cancer group, no correlation was found between previous treatments and vascular crises (p> 0.05). Increased rates of contralateral or uncommon anastomoses were found following neck dissection (p< 0.05). Conclusion: Previous neck dissection or radiotherapy could lead to scarring and tissue damage, which could in turn make microvascular reconstruction more challenging; however, the effect was not definite in this study. Approximately 60% of patients with previous neck dissection had compromised ipsilateral recipient vessels, which resulted in contralateral or uncommon anastomoses. In this study, free-flap reconstruction seems to be quite safe and preferable in patients with recurrent head and neck cancer based on the overall survival rate.

• Journal of Genetic Medicine
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• v.2 no.2
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• pp.59-63
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• 1998

Between 1988-1998, cytogenetic analyses were performed for 1,476 couples and 162 women with recurrent abortions. We applied GTG-banding, high resolution-banding and FISH (fluorescent in situ hybridization) techniques in this study. The frequency of balanced translocations was 3.6% (112/3114). Of them, 74 cases (2.38%) were reciprocal translocations and 38 (1.22%) were robertsonian translocations. Chromosome aberrations were more frequent in women (80 cases) than in men (32 cases). No phenotypical abnormalities were found in all carriers who had experienced recurrent spontaneous abortions or experienced giving birth to malformed offsprings. Prenatal cytogenetic analyses were carried out on 40 subsequent pregnancies for carrier couples with balanced translocation. The fetal karyotypes showed that 13 cases (32.5%) were normal, 25 (62.5%) were balanced translocations, and two (6%) were unbalanced translocations. It is believed that the frequency of chromosomal abnormalities in patients with recurrent spontaneous abortion is higher than that of the normal population. Most of the fetal samples showed normal karyotypes or balanced translocations matching that of one of their parents. Although the incidence of chromosomal imbalance in the fetuses was relatively low in prenatal cytogenetic analysis, individuals with balanced translocations are predisposed to giving birth to malformed offsprings with partial trisomy or monosomy. Therefore, we recommend the cytogenetic and the prenatal cytogenetic analysis for those who experiences recurrent abortion as well as in case they become pregnant, to prevent the birth of offsprings with chromosomal abnormalities.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.17
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• pp.7457-7461
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• 2015

Some thyroid cancer patients undergone insufficient tumor removal in the primary surgery in China. our aim is to evaluate the impact of dissection of the recurrent laryngeal nerve during a salvage thyroid cancer operation in these patients to prevent nerve injury. Clinical data of 49 enrolled patients who received a salvage thyroid operation were retrospectively reviewed. Primary pathology was thyroid papillary cancer. The initial procedure performed included nodulectomy (20 patients), partial thyroidectomy (19 patients) and subtotal thyroidectomy (10 patients). The effect of dissection and protection of the recurrent laryngeal nerve and the mechanism of nerve injury were studied. The cervical courses of the recurrent laryngeal nerves were successfully dissected in all cases. Nerves were adherent to or involved by scars in 22 cases. Three were ligated near the place where the nerve entered the larynx, while another three were cut near the intersection of inferior thyroid artery with the recurrent laryngeal nerve. Light hoarseness occurred to four patients without a preoperative voice change. In conclusion, accurate primary diagnosis allows for a sufficient primary operation to be performed, avoiding insufficient tumor removal that requires a secondary surgery. The most important cause of nerve damage resulted from not identifying the recurrent laryngeal nerve during first surgery, and meticulous dissection during salvage surgery was the most efficient method to avoid nerve damage.

• Radiation Oncology Journal
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• v.37 no.3
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• pp.193-200
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• 2019

Purpose: To explore the role of salvage radiotherapy (RT) for recurrent thymoma as an alternative to surgery. Materials and Methods: Between 2007 and 2015, 47 patients who received salvage RT for recurrent thymoma at Yonsei Cancer Center were included in this study. Recurrent sites included initial tumor bed (n = 4), pleura (n = 19), lung parenchyma (n = 10), distant (n = 9), and multiple regions (n = 5). Three-dimensional conformal and intensity-modulated RT were used in 29 and 18 patients, respectively. Median prescribed dose to gross tumor was 52 Gy (range, 30 to 70 Gy), with equivalent doses in 2-Gy fractions (EQD₂). We investigated overall survival (OS), progression-free survival (PFS), and patterns of failure. Local failure after salvage RT was defined as recurrence at the target volume receiving >50% of the prescription dose. Results: Median follow-up time was 83 months (range, 8 to 299 months). Five-year OS and PFS were 70% and 22%, respectively. The overall response rate was 97.9%; complete response, 34%; partial response, 44.7%; and stable disease, 19.1%. In multivariate analysis, histologic type and salvage RT dose (≥52 Gy, EQD₂) were significantly associated with OS. The high dose group (≥52 Gy, EQD₂) had significantly better outcomes than the low dose group (5-year OS: 80% vs. 59%, p = 0.046; 5-year PFS: 30% vs. 14%, p=0.002). Treatment failure occurred in 34 patients; out-of-field failure was dominant (intra-thoracic recurrence 35.3%; extrathoracic recurrence 11.8%), while local failure rate was 5.8%. Conclusion: Salvage RT for recurrent thymoma using high doses and advanced precision techniques produced favorable outcomes, providing evidence that recurrent thymoma is radiosensitive.

• Archives of Plastic Surgery
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• v.39 no.1
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• pp.71-75
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• 2012

Recurrent laryngeal nerve paralysis is the most common and serious complication after thyroid cancer surgery. The objective of this study was to report the advantages of the vein wrapping technique for nerve reconstruction in patients with thyroid cancer invading the recurrent laryngeal nerve and its effects on postoperative phonatory function. The subjects were three patients who underwent resection of the recurrent laryngeal nerve during surgical extirpation of papillary thyroid cancer. Free ansa cervicalis nerve graft or direct neurorrhaphy with a vein wrapping technique was used to facilitate nerve regeneration, protect the anastomosed nerve site mechanically, and prevent neuroma formation. One-year postoperative laryngoscopic examination revealed good vocal cord mobility. Maximum phonation time ($19.5{\pm}0.3$ sec) was longer than a previously-reported value in conventional reconstruction patients ($18.8{\pm}6.6$ sec). The present phonation efficiency index ($7.88{\pm}0.78$) was higher than that previously calculated in conventional reconstruction ($7.59{\pm}2.82$). The mean value of the Voice Handicap Index-10 was 6, which was within the normal range. This study demonstrates improvement in phonation indices measured 1 year after recurrent laryngeal nerve reconstruction. Our results confirm that the vein wrapping technique has theoretical advantages and could be favored over conventional reconstruction techniques for invenerate nerve injuries.

• Korean Journal of Head & Neck Oncology
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• v.15 no.2
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• pp.166-171
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• 1999

Background and Objectives: The aim of our study was to describe the appearance of recurrent and residual lesions in the head and neck tumors, and to evaluate the usefullness of CT and MRI. Materials and Methods: CT(n=42) and MRI(n=4) of 44 patients with recurrent head and neck tumors were reviewed retrospectively. Primary tumor sites were larynx/hypopharynx in 15, oral cavity/floor of mouth in 13, base of tongue/tonsil in 5, nasopharynx in 4, palate in 2, and others in 5 patients. Therapeutic modalities included sugery and radiotherapy in 23, radiotherapy in 11, surgery in 5, chemotherapy and radiotherapy in 4, and chemotherapy in 1 patient. Results: The patterns of tumor recurrence were nodal recurrence(n=17), primary tumor bed recurrence combined with nodal recurrence(n=12), primary tumor bed recurrence(n=10) and residual primary tumors(n=5). The most common appearance of residual/recurrent primary tumor on CT was focal or diffuse heterogenous mass with or without surrounding fat or muscle infiltration(25/27). On MRI, the recurrent lesions showed intermediate signal intensity on T1 weighted image and high signal intensity on T2 weighted image with heterogenous enhancement in the most cases(n=3). 38 out of 44 nodal recurrences(86%) which had been pathologically or clinically proved were more than 1 cm in diameter or contained central low density on CT scan. Conclusion: Although CT and MRI findings of recurrent and residual tumors of the head and neck were nonspecific, in the majority the lesions manifested as a mass at primary tumor bed and/or nodal disease including contralateral side of the neck. And CT and MRI are valuable for revealing above lesions.