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Giant venous aneurysm (GVA) is a complication of chronic arteriovenous fistula (AVF). The risks of thrombosis, rupture, and massive hemorrhage increase with the increasing size of GVA; therefore, GVA requires treatment. However, the optimal timing and treatments are yet to be established.A 51-year-old male patient who had been undergoing hemodialysis for 10 years using a left radio-cephalic AVF presented to the hospital with an enormous venous aneurysm.Physical examination and ultrasound revealed a GVA in the AVF.The aneurysm was resected, and autogenous AVF was concomitantly formed using the basilic vein. The large wound caused by the removed aneurysm defect was closed using the vessel loop shoelace technique.The wound healed completely, and the patient has been undergoing hemodialysis using the autogenous AVF created during the surgery for 15 months since then.Surgical treatment should be considered for symptomatic GVA. Concomitant aneurysm resection and autogenous AVF formation using the basilic vein may be performed, and the resulting large wound can be closed with the vessel loop shoelace technique to facilitate healing.

This study found that clothing, combined with digital technology, can be a wearable computer that adapts to environmental change and increases biological limits, as well as an emotional space to which art and design are applied, and that promotes mutual communication. A user-friendly interface is proposed for those pursuing a new artistic experience by building a conceptual algorithm for biomorphic clothing sculpture modeling that can be used to create generative designs simply by entering moderated mediator variables. Biomorphic clothing sculpture refers to clothing that is inspired by life in nature and modeled in three dimensions. As the human body and buildings are 3D forms, the parametric design method used frequently in architecture is implemented here and used as a tool to explore attributes and representations of 3D modeling in clothing sculpture design. On the basis of a literature review, this study presents knowledge-based data for biomorphic clothing sculpture that can predict generative design outcomes, and through a case study, identifies the mediator variables and attributes of the parametric process related to biomorphic clothing sculpture modeling. The knowledge-based data on biomorphic clothing sculpture and biomorphic clothing sculpture modeling mediator variables discovered during the research are applied to the 3D modeling process as visual data and presented as the conceptual interface of biomorphic clothing sculpture.

Pneumatosis intestinalis (PI) is a rare condition of the presence of gas within the bowel walls. PI is associated with numerous underlying diseases, ranging from life-threatening to innocuous conditions. PI is believed to be secondary to coexisting disorders in approximately 85% of all cases. This paper reviews the case of a patient who was diagnosed 7 years prior with pneumoperitoneum from unknown causes without any symptoms. The patient was admitted to the intensive care unit for the management of aspiration pneumonia and developed extensive PI after mechanical ventilation, presenting as small bowel obstruction with mesenteric torsion. Although the exact mechanism and etiology of PI are unclear, this case provides an update on the imaging features of and the clinical conditions associated with PI, as well as the management of this condition.

In Korea, an amendment to the Child Welfare Act was made in 2008 that required a national study estimating the occurrence rate of child abuse and neglect every 5 years. The present study reports the major findings of the first national study conducted after the 2008 amendment. The aim of the study is to estimate the prevalence of child physical and psychological maltreatment (CPPM) in Korea and to explore the basic characteristics associated with such incidents. Household surveys were administered to caregivers and focal children who were school age and older. We estimated the prevalence of CPPM using the Parent–child Conflict Tactic Scale, which was developed by Straus et al. (1998). The occurrence rate of CPPM was 25.3 % in Korea, with instances differing by household income, poverty status, and size of the region. Children who experienced physical and psychological maltreatment were more likely to witness the abuse of their siblings and domestic violence. The implications of the findings are discussed and recommendations made for further research.

Human telomerase reverse transcriptase (hTERT), a catalytic subunit of telomerase, is the primary determinant for telomerase enzyme activity, which has been associated with cellular immortality. Expression of the hTERT gene is regulated by various extracellular (external) stimuli and is aberrantly up-regulated in more than 90% of cancers. Here we show that hTERT gene expression was repressed in response to transforming growth factor-β (TGF-β) by a mechanism dependent on transcription factors Snail and c-Myc. TGF-β activated Snail and down-regulated c-Myc gene expression. In addition, ectopic expression of Snail strongly inhibited hTERT promoter activity, although co-expression of c-Myc abrogated this effect. Chromatin immunoprecipitation (ChIP) analysis revealed that TGF-β decreased c-Myc occupancy and dramatically increased recruitment of Snail to the E-box motifs of the hTERT promoter, thereby repressing hTERT expression. Our findings suggest a dynamic alteration in hTERT promoter occupancy by Snail and c-Myc is the mechanistic basis for TGF-β-mediated regulation of hTERT.

Aortic aneurysm is a common and life-threatening disease that can cause death from rupture. Current therapeutic options are limited to surgical or endovascular procedures because no pharmacological approaches have been proven to decrease the chance of expansion or rupture. The best approach to the management of aortic aneurysm would be the understanding and prevention of the processes involved in disease occurrence, progression, and rupture. There is a need for animal models that can reproduce the pathophysiological features of human aortic aneurysm, and several such models have been studied. This review will emphasize recent advances in animal models used in the determination of mechanisms and treatments of aortic aneurysms.

Background Safety and effectiveness of radiofrequency ablation for incompetent small saphenous vein is not established. Objective To report midterm clinical and ultrasonograhic results of radiofrequency ablation (RFA) for small saphenous vein (SSV) in terms of recanalization and sural neuritis. Methods and materials We examined 39 patients (46 limbs) who had been examined using a duplex scan more than 1 year after RFA of SSV. Postoperative clinical results, risk factors for SSV recanalization, and sural neuritis were analyzed. Results CEAP score and CIVIQ2 score improved significantly in all patients (CEAP: 2.45 to 1.43 (p = .03); CIVIQ2: 25.34 to 13.21 (p = .01). SSV obliteration rate was 93.4% at 1 year and 89.1% at 2 years. Preoperative peak reflux velocity in the recanalization group (54.9 cm/s) was significantly higher (p

Muscle-derived stem cells (MDSCs) are known to promote angiogenesis, but have never been studied in vascular diseases. We differentiated MDSCs into endothelial lineage cells in vitro by stimulation with shear stress and vascular endothelial growth factor. Such differentiated MDSCs (diff-MDSC) showed strong angiogenic potential in vitro. When tested in ischemic hindlimbs of mice, diff-MDSCs increased perfusion and decreased necrosis of the ischemic limbs, by promoting new vessel formation and by upregulating genes involved in endothelial expression. Such effects were not observed with native MDSCs (without endothelial stimulation in vitro). Diff-MDSCs were also injected into carotid arteries of rats after balloon denudation of the intima layer to induce intimal hyperplasia. The cell-treated group had significantly reduced intima-to-media thickness ratio compared to control, thus attenuating intimal hyperplasia by early re-endothelialization of the intima layer. Our findings suggest that MDSCs are a potential source of stem cell therapy for treatment of various vascular diseases, by inducing angiogenesis to improve perfusion in sites of ischemia, and by preventing intimal hyperplasia in sites of vessel injury.

Background: BK virus (BKV) has emerged as an important cause of graft dysfunction and failure in renal transplant recipients. Reduction of immunosuppressive therapy is accepted as the primary strategy for management of BKV infection in renal transplant recipients, a strategy which frequently results in graft dysfunction and failure. Herein, a single center experience of BKV infection in renal transplant recipients is presented with an emphasis on the management of BKV infection. Methods: We retrospectively reviewed the medical records of 107 renal transplant recipients who were treated at the outpatient clinic in Seoul National University Bundang Hospital from April 2003 to April 2011. The effects of the modification of immunosuppression on the replication of BKV and graft outcome were analyzed. Results: Of a total of 35 patient evaluated for BKV infection, 20 tested positive in at least one BK virus test. Decoy cells in urine were detected in 13 of the 20 patients. Of these patients, 7 developed BKV nephropathy. Four out of seven of the BKV nephropathy patients were diagnosed with biopsy, and the other three were diagnosed based on a high titer of BKV replication detected in plasma samples. Despite the reduction in immunosuppression and use of leflunomide in the seven BKV nephropathy patients, two patients suffered deterioration of renal function and one patient lost the graft with progressive renal dysfunction. Conclusions: BK virus nephropathy was not an uncommon disease and was a major cause of graft dysfunction or loss. Appropriate modification of immunosuppressive therapy, early in the course of BK nephropathy or before the occurrence of massive replication of BKV, is essential for the protection of renal allografts.

This study locates typical Korean fashion images in domestic and foreign fashion journals to advance Korea`s international image in contemporary global fashion markets. The investigation of the frequency of articles and their types (so as to inquire into interest in Korean fashion in the global fashion markets) showed that for the appearance frequency of domestic articles studied, a good number of articles were published in the first half of 2008 and in 2009. In the case of foreign articles, the number of them increased from the second half of 2008 and the majority of articles were shown in the first half of 2010. Second, the investigation of the appearance features by article type studied in order to understand how Korean fashion played a role in the world`s markets. The majority of articles were related to fashion brands that entered Chinese market in fashion brand articles in the case of domestic articles; however, many foreign articles introduced designers that participated in global fashion collections in Paris and New York. Third, as a result of analyzing typical key words by article type in order to find key words which could enhance Korea`s fashion national image representing, we could confirm that `Korean designers` can be a typical key words to represent Korean fashion. The key word most exposed in both domestic and foreign articles was `designer Lie Sang Bong` and only his articles contained the content about influential Korean design materials.

Purpose: Cyclooxygenase-2 is believed to be an important enzyme in the pathogenesis of colorectal cancer (CRC). Cytosolic phospholipase A2 (cPLA2), also, have been suggested to be related to the carcinogenesis of CRC. The aim of this study was to investigate cPLA2 expression and its relationship with prognostic significance in CRC. Methods: Eighty-eight patients with colorectal cancer who underwent curative surgery were enrolled in this study. cPLA2 was examined in 88 primary CRCs by immunohistochemistry and we compared their expression with clinicopathologic findings, recurrence and survival in patients with CRC. Results: The expression of cPLA2 was positive in 54.5% (48/88). The expression of cPLA2 was not correlated with clinicopathologic parameters. However, cPLA2 expression was significantly related with vascular endothelial growth factor expression. Kaplan-Meier analysis didn’t show any clinical significance in disease-free survival and overall survival according to cPLA2 expression. Conclusion: These results suggest that cPLA2 expression was not associated with the prognosis of CRC. However, further large-scale studies are needed to clarify the prognostic effect of cPLA2 in CRC.

This study aimed to analyze the expression of Hybrid in Contemporary Hair Design that is one kind of total fashion. In this research, by background of the hybrid characteristics of the messes culture art, the hybrid characteristics of the hair design has been defined as characters which is the mixture of timeless spaces, styles, sexes, unsuitable elements and cultures. The results of analysis by the expression of the hybrid hair design after 2000 is like this. As the researching, the hybrid characteristics of the hair design by the mixture of unsuitable elements and styles have been presented the highest. The result of the frequency of the apparition in the hair design molding elements according to the expression of the hybrid hair design, the hybrid characteristics of the unsuitable elements and style has been presented ideological form and the artificial form was the highest. The case of the hybrid of the activated texture, the unsuitable elements, style and timeless space has been presented excellently one after another. In the color tone, the mixture of the style, the unsuitable elements and timeless space has been presented one by one. The case of the hybrid of the image, the unsuitable elements that is the highest the frequency of the apparition was presented the image of the avant-garde, the fantastic and humor one after another.

Recently, the environmental problems have surfaced as serious social issues. More people become aware of the environments and seek for new kinds of lifestyle Lohas. The purpose of this study was to investigate the expressional characteristics of Lohas fashion design in ready-to-wear collection from 2000 till 2005. In the study, green design which was the base of Lohas fashion, was first examined, which was followed by an analysis of Lohas styles to understand the green design-oriented characteristics of Lohas fashion in the current fashion trends. The findings were as follows: First, the lifestyle of Lohas values `environment-friendliness`, `sustainability`, `importance of health` and `sensitivity`. Second, the distinguishing features of Lohas lifestyle categorize the Lohas fashion into five different looks: `Lohas Natural Look`, `Lohas Vintage Look`, `Lohas Redesign Look`, `Lohas Multi look`, and `Lohas Wellness Look`. This study set out to provide useful results to be used as the basic data in studying design and related areas where they would develop fashion products for the consumers with the latest tastes as well as to promote environment protection.

In this paper, we propose an orientation tracking method and a digestion path model based on angular displacement. The proposed method expresses a capsule`s orientation as 3-dimension vectors and its rotation angle. Errors in roll, pitch, and yaw representing capsule`s orientation information is down to . Using the proposed method we can measure a roll which is not Possible to be measured using the magnetic field method. We reduce algorithm complexity lower than a previous methods based on Euler angle.

The purpose of this study is to examine the expressional characteristics of T-shirts design using digital printing. Through digital printing system, a variety of patterns and pictures can be printed on T-shirts in a relatively short time. At this backdrop, the result of this research can aid to develop design of T-shirts with a high value added on it. The result was that the printing methods were categorized into borrowing the pictures of masterpieces, applying photography or caricatures, introducing graffiti or lettering, and representing industrial arts. In conclusion, digital printing system unlike the established printing method can have almost an unlimited range of expressing various kinds of pictures and patterns, so that designers may develop high value-added differentiated T-shirts. In other words, by creating a variety of designs with no limit of its quantity, its expressive range can be more widened and with an increased development of plotting machines, we may manufacture more varied kinds of products in a small quantity at a faster rate.

Semiconductor manufacturing industry has growing concerns over future environmental impacts as fabs expand and new generations of equipment become more powerful. Especially rare gases supply and price are one of prime concerns for operation of high volume manufacturing (HVM) fabs. Over the past year it has come to our attention that Helium and Neon gas supplies could be unstable and become a threat to HVM fabs. To address these concerns, Gigaphoton has implemented various green technologies under its EcoPhoton program. One of the initiatives is GigaTwin deep ultraviolet (DUV) lithography laser design which enables highly efficient and stable operation. Under this design laser systems run with 50% less electric energy and gas consumption compared to conventional laser designs. In 2014 we have developed two technologies to further reduce electric energy and gas efficiency. The electric energy reduction technology is called eGRYCOS (enhanced Gigaphoton Recycled Chamber Operation System), and it reduces electric energy by 15% without compromising any of laser performances. eGRYCOS system has a sophisticated gas flow design so that we can reduce cross-flow-fan rotation speed. The gas reduction technology is called eTGM (enhanced Total gas Manager) and it improves gas management system optimizing the gas injection and exhaust amount based on laser performances, resulting in 50% gas savings. The next steps in our roadmap technologies are indicated and we call for potential partners to work with us based on OPEN INNOVATION concept to successfully develop faster and better solutions in all possible areas where green innovation may exist.

Protein kinase Cα (PKCα) phosphorylates the Ser33/37/Thr41 residues of β-catenin, which lacks a typical PKCα canonical sequence, but little is known about its underlying mechanism. Here we showed that Ser33/Ser37/Thr41 of β-catenin fragments encompassing the armadillo repeats 1–5 (β-catenin1–781, β-catenin1–682, and β-catenin1–422) are phosphorylated by PKCα whereas β-catenin1–138 lacking these repeats is not phosphorylated. Binding-site analysis revealed that PKCα directly interacts with β-catenin through the sites on the armadillo repeats 1–5. In addition, axin fragments (365–500), which interacts with β-catenin through armadillo repeats 3–5, disrupted PKCα/β-catenin association and inhibited β-catenin phosphorylation by PKCα. In HEK293 cells, the levels of β-catenin1–781 and β-catenin1–422 were decreased whereas the amount of β-catenin1–138 was unchanged by pharmacological stimulation of PKCα. Our results suggest that the association of PKCα with the armadillo repeats of β-catenin placed the Ser33/37/Thr41 residues of β-catenin in close proximity to PKCα, thereby facilitating PKCα-mediated β-catenin phosphorylation.

Purpose To examine the fate of muscle-derived stem cells (MDSC) after injection into different host conditions and provide an insight for their mechanism of action. Materials and methods MDSCs differentiated in vitro towards the endothelial lineage and transfected with lentivirus tagged with green fluorescent protein (GFP) were injected into two animal models mimicking vascular diseases: hindlimb ischemia and carotid injury models. Injected cells were tracked at the site of injection and in remote organs by harvesting the respective tissues at different time intervals and performing immunofluorescent histological analyses. Stem cell survival was quantified at the site of injection for up to 4 weeks. Results MDSCs were successfully tagged with fluorescent material GFP and showed successful implantation into the respective injection sites. These cells showed a higher affinity to implant in blood vessel walls as shown by double fluorescent co-stain with CD31. Quantification of stem cell survival showed a timede pendent decrease from day 3 to 4 weeks (survival rate normalized against day 3 was 72.0% at 1 week, 26.8% at 2 weeks and 2.4% at 4 weeks). Stem cells were also found in distant organs, especially the kidneys and liver, which survived up to 4 weeks. Conclusion MDSCs were successfully tracked in different vascular disease models, and their fate was assessed in terms of cell survival and distribution. Better understanding of the donor cell properties, including their interaction with the host conditions and their mechanism of action, are needed to enhance cell survival and achieve improved outcomes.

Secondary lymphedema is an intractable disease mainly caused by damage of the lymphatic system during surgery, yet studies are limited by the lack of suitable animal models. The purpose of this study was to create an improved model of secondary lymphedema in the hindlimbs of rodents with sustained effects and able to mimic human lymphedema. This was achieved by combining previously reported surgical methods and radiation to induce chronic lymphedema. Despite more radical surgical destruction of superficial and deep lymphatic vessels, surgery alone was not enough to sustain increased hindlimb volume. Radiotherapy was necessary to prolong these effects, with decreased lymphatic flow on lymphoscintigraphy, but hindlimb necrosis occurred after 4 weeks due to radiation toxicity. The applicability of this model for studies of therapeutic lymphangiogenesis was subsequently tested by injecting muscle-derived stem cells previously cocultured with the supernatant of human lymphatic endothelial cells in vitro. There was a tendency for increased lymphatic flow which significantly increased lymphatic vessel formation after cell injection, but attenuation of hindlimb volume was not observed. These results suggest that further refinement of the rodent hindlimb model is needed by titration of adequate radiation dosage, while stem cell lymphangiogenesis seems to be a promising approach.

Abdominal aortic aneurysms (AAA) are a growing problem worldwide, yet there is no known medical therapy. The pathogenesis involves degradation of the elastic lamina by two combined mechanisms: increased degradation of elastin by matrix metalloproteinases (MMP) and decreased formation of elastin due to apoptosis of vascular smooth muscle cells (VSMC). In this study, we set out to examine the potential role of stem cells in the attenuation of AAA formation by inhibition of these pathogenetic mechanisms. Muscle-derived stem cells from murine skeletal muscles were isolated and stimulated with PDGF-BB in vitro for differentiation to VSMC-like progenitor cells (VSMC-PC). These cells were implanted in to elastase-induced AAAs in rats. The cell therapy group had decreased rate of aneurysm formation compared to control, and MMP expression at the genetic, protein and enzymatic level were also significantly decreased. Furthermore, direct implantation of VSMC-PCs in the intima of harvested aortas was visualized under immunofluorescent staining, suggesting that these cells were responsible for the inhibition of MMPs and consequent attenuation of AAA formation. These results show a promising role of stem cell therapy for the treatment of AAAs, and with further studies, may be able to reach clinical significance.

Esophageal necrosis with perforation secondary to traumatic aortic transection is extremely rare but usually fatal. A 47-year-old man complained of sudden swallowing difficulty 6 days after blunt trauma. Computed tomography showed a ruptured aorta and the midesophagus shifted to the right side with luminal obliteration because of the ruptured aorta. After primary repair of the partially transected aorta, unexpected mediastinitis because of esophageal perforation was noted. Upper endoscopy showed midesophageal ulceration, necrosis, and perforation. Biopsy samples were consistent with ischemia. The possibility of direct esophageal trauma or intraoperative esophageal injury was ruled out. Esophageal exclusion with thoracoscopic decortication and multiple antibiotics were ineffective, and the patient eventually died. Ischemic esophageal necrosis caused by mechanical compression can occur in a traumatic aortic transection. Dysphagia, when present with radiologic signs, indicates a displaced and compressed esophagus. In spite of aggressive surgical and medical treatment for a perforated esophagus, the prognosis remains poor.

Dorsal extradural migration of extruded disc material is clinically uncommon. We report a rare case of posterior epidural migration of an extruded lumbar disc mimicking a facet cyst. A 32-year-old man was admitted to our institute with a 2-week history of severe low back pain and radiating pain in the left leg. The magnetic resonance (MR) images revealed a dorsally located, left-sided extradural cystic mass at the L2-3 level. The initial diagnosis was an epidural facet cyst because of the high signal intensity on MR images and its location adjacent to the facet joint. Intraoperatively, an encapsulated mass of soft tissue adherent to the dural sac was observed and excised. The pathological diagnosis was degenerated disc material. After surgery, the patient experienced complete relief from leg pain.

Purpose: This study was designed to determine the factors affecting completion of critical pathway for elective gastrectomy. Methods: Since 2008, a critical pathway has been applied for elective gastrectomy at Chosun University Hospital. We retrospectively analyzed 252 patients who underwent elective gastrectomies from January 2009 to April 2013. The completion rate was determined, and risk factors for patient dropout were examined. Results: The completion rate of the critical pathway was 45.6% (115/252). Mean length of stay was 11.7 ± 8.6 days (8?59 days). Readmission rates were 4.4% (11/252). Causes of failure for clinical pathway were systemic complications (21/137, 15.3%), intra-abdominal complications (44/137, 32.8%), patient factors (41/137, 29.9%), and wound complications (30/137, 21.9%). There were no significant differences between the two groups in age, sex, American Society of Anesthesiologists (ASA) score, operation time, readmission, and underlying disease (P > 0.05). Body mass index (P = 0.008) and pathologic stage (P = 0.001) were significantly different between the two groups. In multivariate analysis, the conventional approach (odds ratio, 2.0), and total gastrectomy (odds ratio, 5.3) were determined to be independent risk factors to drop the critical pathway. But there were no significant differences between total and distal gastrectomy groups in age, gender, underlying diseases, ASA score, readmission, operation time, and cause of dropout (P > 0.05). Conclusion: We concluded that total gastrectomy may not be suitable for the critical pathway. We suggest that the critical pathway for elective distal gastrectomy is divided 2 subgroups, according to the surgical approach.

Purpose: With the development of diagnostic techniques, second primary neoplasms such as synchronous or metachronous cancers in gastric cancer patients are being increasingly found. In this study, we investigated the clinicopathological features and clinical significance of gastric neoplasms combined with synchronous and metachronous cancers. Materials and Methods: 1,048 patients who were diagnosed with gastric cancer in Chosun University Hospital from January 1998 to March 2008 were retrospectively reviewed. Results: 38 of the 1,048 patients with gastric cancer (3.6%) had synchronous and metachronous cancers. Of the 38 patients, 16 patients (42.1%) had synchronous cancer and 22 patients (57.9%) had metachronous cancer. The average time interval between gastric cancer and the secondary primary cancer was months. The most common second primary neoplasm was lung cancer (8/38, 21.1%), followed by colorectal cancer (8/38, 21.1%). Among the 27 patients who underwent surgical resection for gastric cancer, 5 patients (18.5%) were in the synchronous group and 22 patients (81.5%) were in the metachronous group. The mean survival time of the 38 patients was 49.8 months. The mean survival time was 24.6 months for the synchronous cancer patients and 68.1 month for the metachronous cancer patients. The 3 year survival rate of the synchronous group and the metachronous group was 33.3% and 81.1%, respectively. Conclusion: We must pay attention on the preoperative workup for synchronous cancer and on the postoperative follow-up for metachronous cancer in gastric cancer patients.

Purpose: Papillary thyroid microcarcinomas (PTMC), which are not palpable and have no clinical symptoms are 1.0 cm or less in diameter. The optimal extent of thyroid tumor resection has been controversial. We investigated clinicopathological findings of PTMC of 5 mm or less in diameter for reasonable therapeutic approach. Methods: From, Jan. 2002 to Dec. 2006, 366 patients underwent thyroidectomy for thyroid papillary carcinoma at our institution. Among these patients, 62 patients with a mass measuring less than 5 mm and 103 patients with a mass 5 mm to 1.0 cm were selected. We retrospectively reviewed their medical records. Results: There was no significant difference on the clinical characteristics except multifocality. We performed more unilateral lobectomy, near total thyroidectomy with or without neck node dissection in patients with PTMC of less than 5 mm (P=0.13). In permanent biopsy, lymph node metastasis more frequently occurred in patients with PTMC of less than 5 mm (P=0.03). There were no differences in capsular invasion, distant metastasis or recurrence. Conclusion: In papillary thyroid microcarcinoma less than 0.5 cm, it is very uncommon for capsular invasion, distant metastasis and locoregional metastasis to exist. The extent of tumor resection may be limited less than near total thyroidectomy for suitable cases, because there was no locoregional metastasis or distant metastasis in the follow-up period. Longer follow-up periods would be required to confirm that limited surgery is sufficient for tumors less than 0.5 cm in size.