Clinical Efficacy and Safety of Endoscopic Treatment of Gastrointestinal Stromal Tumors in the Stomach

Background/Aims@#Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors in the stomach. We evaluated the clinical outcomes of endoscopic treatment for gastric GISTs. @*Methods@#This is a single center, retrospective study that enrolled 135 cases of gastric subepithelial tumors (SETs) resected by endoscopic procedures and confirmed as GISTs by histopathology from March 2005 to July 2019. The immediate and long-term clinical outcomes were analyzed retrospectively. @*Results@#The mean patient age was 57.9 years, and the mean tumor size was 2.1 cm. Of the tumors, 43.0% were located in the body, followed by the fundus (26.7%) and cardia (17.0%). Most tumors (85.2%) were resected by endoscopic submucosal dissection, followed by endoscopic mucosal resection (6.7%), submucosal tunneling endoscopic resection (5.9%), and endoscopic full-thickness resection (2.2%). Macroperforation occurred in 4.4% and microperforation in 6.7% of the cases. The R0 resection rate was 15.6%. However, the rate of complete resection by the endoscopic view was 90.4%, of which 54.8% of cases were in the very-low-risk group, followed by the low-risk group (28.1%), intermediate-risk group (11.9%), and high-risk group (5.2%). During 36.5 months of follow-up, recurrence was found in four (3.4%) of the 118 patients who were monitored for more than 6 months (low-risk group, 1/37 [2.7%]; intermediate-risk group, 2/11 [18.2%]; high-risk group, 1/6 [16.7%]). @*Conclusions@#Endoscopic treatment of a GIST appears to be a feasible procedure in selected cases. However, additional surgery should be considered if the pathologic results correspond to intermediate- or high-risk groups.

Safe and appropriate use of laxatives for colonoscopy

Appropriate bowel preparation is essential for effective colonoscopy. Inadequate use of bowel preparation solutions reduces patient compliance, makes the detection of lesions such as adenoma difficult, and increases the risk of complication such as perforation. Current Concepts: A 4-L polyethylene glycol (PEG) solution can be safely used for bowel preparation, even in most individuals with underlying diseases. However, it requires a high preparation-volume intake and has poor patient compliance due to its unpleasant taste. Therefore, a 2- or 1- L sulfate-free, PEG-based laxative was developed to, reduce the amount of PEG and improve the taste. Furthermore, simethicon-containing laxative formulation was developed to eliminate gas bubbles. In addition, oral bowel preparation solutions with enema agents and prokinetics were used to improve bowel preparation, but no improvement was observed. Various alternative laxatives are available; however, PEG-based bowel preparation solutions are still recommended in most cases due to their stability. Discussion and Conclusion: Although a 4-L PEG solutions recommended for bowel preparation in most cases, several laxatives have been introduced to overcome its disadvantages. The laxative agent must be selected according to each patient’s specific characteristics. Moreover, the method of taking bowel preparation solutions and additional bowel preparation medications must be carefully chosen. In addition, patient education via various methods, such as using a smartphone, when taking a bowel preparation agent may help improve bowel preparation quality.

Safe and appropriate use of laxatives for colonoscopy

Appropriate bowel preparation is essential for effective colonoscopy. Inadequate use of bowel preparation solutions reduces patient compliance, makes the detection of lesions such as adenoma difficult, and increases the risk of complication such as perforation. Current Concepts: A 4-L polyethylene glycol (PEG) solution can be safely used for bowel preparation, even in most individuals with underlying diseases. However, it requires a high preparation-volume intake and has poor patient compliance due to its unpleasant taste. Therefore, a 2- or 1- L sulfate-free, PEG-based laxative was developed to, reduce the amount of PEG and improve the taste. Furthermore, simethicon-containing laxative formulation was developed to eliminate gas bubbles. In addition, oral bowel preparation solutions with enema agents and prokinetics were used to improve bowel preparation, but no improvement was observed. Various alternative laxatives are available; however, PEG-based bowel preparation solutions are still recommended in most cases due to their stability. Discussion and Conclusion: Although a 4-L PEG solutions recommended for bowel preparation in most cases, several laxatives have been introduced to overcome its disadvantages. The laxative agent must be selected according to each patient’s specific characteristics. Moreover, the method of taking bowel preparation solutions and additional bowel preparation medications must be carefully chosen. In addition, patient education via various methods, such as using a smartphone, when taking a bowel preparation agent may help improve bowel preparation quality.

Clinicopathological Features of Small Bowel Tumors Diagnosed by Video Capsule Endoscopy and Balloon-Assisted Enteroscopy: A Single Center Experience

Background/Aims@#Small bowel malignancies often present a diagnostic challenge due to their relative rarity and nonspecific clinical symptoms. However, technical developments in endoscopic instruments, including video capsule endoscopy (VCE) and enteroscopy, have allowed for the visualization of the entire small bowel. This study aimed to investigate the clinicopathological features of small bowel malignant tumors diagnosed by VCE and double-balloon enteroscopy (DBE) in a single tertiary center. @*Methods@#We retrospectively analyzed VCE and DBE findings from Korea University Guro Hospital from January 2010 through September 2018. @*Results@#A total of 510 VCE and 126 DBE examinations were performed in 478 patients. Small bowel malignancies were diagnosed in 28 patients (15 males; mean age, 61.0 years; range, 42 to 81 years). Among them, 8 had lymphoma, 8 had primary adenocarcinoma, 7 had gastrointestinal stromal tumor (GIST) and 5 had metastatic cancer. Abdominal pain and obstructive symptoms were the most common findings in metastatic cancers (4/5, 80%). On the other hand, obscure gastrointestinal bleeding was the most common symptom of GIST (6/7, 85.7%) and adenocarcinoma (3/8, 37.5%). @*Conclusions@#Approximately 6% of the patients who underwent either VCE or DBE were diagnosed with small bowel malignancy. These findings demonstrated the different clinical characteristics among small bowel malignancies and merit further study.

Externally Monitored Versus Conventional Buried Flaps in Laryngopharyngeal Reconstruction

Objectives@#. To compare the surgical outcomes of externally monitored and conventional buried flaps with the goal of determining the usefulness of external monitoring of buried flaps. @*Methods@#. In this case-control study with propensity score matching, 30 patients were evenly divided into externally monitored buried flap and conventional buried flap groups. The total operative time for free flap reconstruction, the flap survival rate, the length of hospital stay, the initial time of a reliable visual assessment, complications, the final diet achieved, and the duration until diet initiation were compared between the groups. @*Results@#. The mean operative time for reconstruction was 115 minutes (interquartile range, 85–150 minutes) and 142 minutes (interquartile range, 95–180 minutes) in the externally monitored and conventional groups, respectively (P= 0.245). The median length of hospital stay was 24 days (interquartile range, 18–30 days) and 27 days (interquartile range, 20–41 days) in the externally monitored and conventional groups, respectively (P=0.298). The median duration until diet initiation was 15 days (interquartile range, 15–21 days) and 18 days (interquartile range, 15–34 days) in the externally monitored and conventional groups, respectively (P=0.466). The final diet, initial time of a reliable visual assessment, and complications were comparable between the groups, but the external skin paddle provided an excellent visual assessment immediately postoperatively in all cases. @*Conclusion@#. The outcomes were comparable between the groups, indicating that externalization of the cutaneous component of a buried flap may be a straightforward and useful technique for monitoring a buried anterolateral thigh free flap in laryngopharyngeal reconstructions. The salvage and false-positive rates of compromised flaps should be compared in large subject groups in future studies to prove that the use of an external skin paddle improves flap monitoring.

Combined Treatment with Methylprednisolone and Human Bone Marrow-Derived Mesenchymal Stem Cells Ameliorate Experimental Autoimmune Encephalomyelitis

Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system. Although advances have been made in the treatment of MS, such as the use of IFN-β, glucocorticoids and stem cells, the therapeutic effects of these treatments are not sufficient. In the present study, we evaluated whether the combination of methylprednisolone (MP) and human bone marrow-derived mesenchymal stem cells (BM-MSCs) could enhance the therapeutic effectiveness in experimental autoimmune encephalomyelitis (EAE), a model for MS. EAE was induced by immunizing C57BL/6 mice with myelin oligodendrocyte glycoprotein 35-55 (MOG 35-55). The immunized mice received an intraperitoneal injection of MP (20 mg/kg), an intravenous injection of BM-MSCs (1 × 10⁶ cells) or both on day 14 after immunization. Combination treatment significantly ameliorated the clinical symptoms, along with attenuating inflammatory infiltration and demyelination, compared to either treatment alone. Secretion of pro-inflammatory cytokines (IFN-γ, TNF-α, IL-17) was significantly reduced, and anti-inflammatory cytokines (IL-4, IL-10) was significantly increased by the combination treatment as compared to either treatment alone. Flow cytometry analysis of MOG-reactivated T cells in spleen showed that combination treatment reduced the number of CD4⁺CD45⁺ and CD8⁺ T cells, and increased the number of CD4⁺CD25⁺Foxp3⁺ regulatory T cells. Furthermore, combination treatment enhanced apoptosis in MOG-reactivated CD4⁺ T cells, a key cellular subset in MS pathogenesis. Combination treatment with MP and BM-MSCs provides a novel treatment protocol for enhancing therapeutic effects in MS.

A Case of Tracheal Defect Reconstruction Using Anterolateral Thigh Free Flap in Patients with Papillary Thyroid Carcinoma Invading Tracheal Cartilage / 대한이비인후과학회지

When a well-differentiated thyroid carcinoma invades the adjacent organ, the treatment of choice is en bloc surgical resection. After tracheal resection, the tracheal defect can be repaired in various ways. Depending on the invasion depth of the tumor or the defect circumference of the trachea, primary closure, reconstruction of surrounding muscles, or end-to-end anastomosis can be used. A 70-year-old man was diagnosed with papillary thyroid cancer with tracheal invasion. The patient was treated by total thyroidectomy with tracheal window resection of the invading trachea. The defect was reconstructed with an anterolateral thigh free flap. At 12 months after surgery, the patient leads a social life without any discomfort and has an acceptable voice. This case is reported along with associated techniques and reviews of related articles.

The Role of Virtual Surgical Planning in the Era of Robotic Surgery

Among various surgical methods introduced to optimize esthetic results, robotic surgery has gradually expanded in scope. As incision, approach, and operation view in robotic surgery differ from existing surgical methods, we should consider reconstruction from a different perspective. We recently experienced two mandibular reconstruction cases after tumor ablative surgery with robotic neck dissection using the conventional reconstruction method and virtual surgical planning (VSP), respectively. We found that the conventional reconstruction method is inappropriate in modified facelift incision in robotic neck dissection because it provides limited surgical scope, restricts access to the defect area, and therefore, consumes considerable time before anastomosis. For these reasons, the authors consider VSP far more viable in the era of robotic surgery.

Severe Endobronchial Inflammation Induced by Aspiration of a Ferrous Sulfate Tablet / 결핵및호흡기질환

Iron supplements such as ferrous sulfate tablets are usually used to treat iron-deficiency anemia in some elderly patients with primary neurologic disorders or decreased gag reflexes due to stroke, senile dementia, or parkinsonism. While the aspiration of ferrous sulfate is rarely reported, it is a potentially life-threatening condition that can lead to airway necrosis and bronchial stenosis. A detailed history and high suspicion of aspiration are required to avoid delays in diagnosis and treatment. The diagnosis can be confirmed by bronchoscopic examination and a tissue biopsy. Early removal of the aspirated tablet prevents acute complications, such as bronchial necrosis, hemoptysis, and lobar consolidation. Tablet removal is also necessary to prevent late bronchial stenosis. We presented the first case in Korea of a ferrous sulfate tablet aspiration that induced severe endobronchial inflammation.

Anterolateral Thigh Thickness Measurement in Positron Emission Tomography-Computed Tomography for the Prediction of Free Flap Reconstruction Outcomes in Head and Neck Cancer / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Anterolateral thigh (ALT) flaps are commonly used for head and neck surgery reconstruction. However, a thick ALT often leads to long operation times. Therefore, ALT thickness on a preoperative non contrast image of positron emission tomography-computed tomography (PET-CT) scan was measured to predict surgical outcome. SUBJECTS AND METHOD: The correlation between ALT thickness and total reconstruction time was analyzed in 106 patients. The differences in ALT thickness between the successful and compromised-flap groups were analyzed retrospectively. RESULTS: Median ALT thickness was 4.49 mm, and total reconstruction time was 190 min. Total reconstruction time was significantly correlated with ALT thickness (p=0.019). ALT thickness, body mass index (BMI), total reconstruction time and ischemia time were significantly greater in the compromised-flap group than in the successful group. In the multivariate analysis, only BMI and ischemia time were predictors for the compromised flap. CONCLUSION: ALT thickness measured on a non-contrast image of PET-CT scan is useful as a surgical outcome predictor with respect to total reconstruction time. A further study may suggest the risk of a thick ALT in a compromised flap in head and neck reconstruction using an ALT free flap.

Hypoxia Induces Epithelial-Mesenchymal Transition in Follicular Thyroid Cancer: Involvement of Regulation of Twist by Hypoxia Inducible Factor-1alpha

PURPOSE: Although follicular thyroid cancer (FTC) has a relatively fair prognosis, distant metastasis sometimes results in poor prognosis and survival. There is little understanding of the mechanisms contributing to the aggressiveness potential of thyroid cancer. We showed that hypoxia inducible factor-1alpha (HIF-1alpha) induced aggressiveness in FTC cells and identified the underlying mechanism of the HIF-1alpha-induced invasive characteristics. MATERIALS AND METHODS: Cells were cultured under controlled hypoxic environments (1% O2) or normoxic conditions. The effect of hypoxia on HIF-1alpha, and epithelial-to-mesenchymal transition (EMT) related markers were evaluated by quantitative real-time PCR, Western blot analysis and immunocytochemistry. Invasion and wound healing assay were conducted to identify functional character of EMT. The involvement of HIF-1alpha and Twist in EMT were studied using gene overexpression or silencing. After orthotopic nude mouse model was established using the cells transfected with lentiviral shHIF-1alpha, tissue analysis was done. RESULTS: Hypoxia induces HIF-1alpha expression and EMT, including typical morphologic changes, cadherin shift, and increased vimentin expression. We showed that overexpression of HIF-1alpha via transfection resulted in the aforementioned changes without hypoxia, and repression of HIF-1alpha with RNA interference suppressed hypoxia-induced HIF-1alpha and EMT. Furthermore, we also observed that Twist expression was regulated by HIF-1alpha. These were confirmed in the orthotopic FTC model. CONCLUSION: Hypoxia induced HIF-1alpha, which in turn induced EMT, resulting in the increased capacity for invasion and migration of cells via regulation of the Twist signal pathway in FTC cells. These findings provide insight into a possible therapeutic strategy to prevent invasive and metastatic FTC.

Development and clinical evaluation of a rapid diagnostic kit for feline leukemia virus infection

Feline leukemia virus (FeLV) causes a range of neoplastic and degenerative diseases in cats. To obtain a more sensitive and convenient diagnosis of the disease, we prepared monoclonal antibodies specific for the FeLV p27 to develop a rapid diagnostic test with enhanced sensitivity and specificity. Among these antibodies, we identified two clones (hybridomas 8F8B5 and 8G7D1) that specifically bound to FeLV and were very suitable for a diagnostic kit. The affinity constants for 8F8B5 and 8G7D1 were 0.35 x 10(9) and 0.86 x 10(9), respectively. To investigate the diagnostic abilities of the rapid kit using these antibodies, we performed several clinical studies. Assessment of analytical sensitivity revealed that the detection threshold of the rapid diagnostic test was 2 ng/mL for recombinant p27 and 12.5 x 10(4) IU/mL for FeLV. When evaluating 252 cat sera samples, the kit was found to have a kappa value of 0.88 compared to polymerase chain reaction (PCR), indicating a significant correlation between data from the rapid diagnostic test and PCR. Sensitivity and specificity of the kit were 95.2% (20/21) and 98.5% (257/261), respectively. Our results demonstrated that the rapid diagnostic test would be a suitable diagnostic tool for the rapid detection of FeLV infection in cats.

Oncologic and Functional Outcomes of Supraglottic Partial Laryngectomy: 18 Years Experience / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Supraglottic partial laryngectomy (SPL), which provides the removal of selected tumors involving the upper structure of the glottis, shows equivalent oncologic outcome when compared to total laryngectomy with functional preservation. We report our 18-year experience of applying supraglottic partial laryngectomy in the Yonsei Head and Neck Cancer Clinic. SUBJECTS AND METHOD: We retrospectively reviewed the charts of 78 patients who underwent SPL. We divided the patients into two groups, the early and the recent, and performed Kaplan-Meier survival analysis and chi2-test on the groups. The post-operative functional outcome was assessed. RESULTS: The 3-year-disease-specific survival rate of the early and recent period was 87% and 84.6%, respectively. Decannulation and tolerability of an oral diet was possible in 93% and 95% of the earlier group, and 95% and 98% in the recent group, respectively. There was no statistically significant difference in survival rate, recurrence pattern, decannulation and tolerability of oral diet between the two groups. CONCLUSION: We achieved a satisfactory survival rate through SPL. In addition, almost all patients could be decannulated and eventually tolerated an oral diet. Our results confirm that SPL is an oncologically & functionally sound procedure for selected supraglottic tumors.

Endoscopic Thyroidectomy via an Axillo-Breast Approach without Gas Insufflation for Benign Thyroid Nodules and Micropapillary Carcinomas: Preliminary Results

PURPOSE: To examine the feasibility of endoscopic thyroidectomy (ET) via an axillo-breast approach without gas insufflation for large thyroid tumors and micropapillary carcinomas. MATERIALS AND METHODS: The patients in the benign group were separated into groups 1 (n=95, or =4 cm in tumor diameter). Also, 57 patients in the micropapillary carcinoma group underwent an endoscopic hemithyroidectomy (HT) (group 3) and were compared with 60 patients who received conventional open HT (group 4). Postoperative functional outcome, local complications, surgical outcomes, and pathological outcomes were compared between the groups. RESULTS: In the benign group, there was no significant difference in mean operating time, hospital stay, or overall perioperative complications between the two groups. In the micropapillary carcinoma group, mean operating time and hospital stay in group 3 were significantly longer than in group 4 (p=0.015 and p or =4 cm and micropapillary carcinomas. Although it has the advantage of better cosmetic results over open thyroidectomy, there is room for improvement in terms of lessening its invasiveness and shortening the operative time.

Influence of Phenilamine on Pressor Responses of Norepinephrine and Tyramine

The effect of Pheniramine(Avil), a histaminergic-1 receptor blocking agent presently employed in treating various allergic diseases on pressor actions of norepinephring(NE) and tyramine (TR) was studied in the rabbit. Pheniramine, when given into a femoral vein with a dose(3mg/kg) enough to block H1-receptor, potentiated markedly the pressor responses of NE and TR. The pressor action of NE augmented by pheniramine was not affected by additional adminstration of debrisoquin (Drenergic neuron blocker) or phenelzine(monoamine oxidase inhibitor) or desipramine(U1-uptake blocker), or while potentiated by additional treatment with chlorisondamine(ganglionic blocker)or reserpine(catecholamine depleter). The hypertensive response of NE to phenelzine or desipramine was reinforced significantly by addition of pheniramine, but the response of NE in rabbits treated with reserpine or chlorisondamine or debrisoquin was not influenced by pheniramine-addition. Elevation of blood pressure to TR potentiated by pheniramine was attenuated significantly by reserpine treatment with chlorisondamine made the significant augmentation of pressor action to TR after pheniramine. Tyramine-induced response of blood pressure after pheniramine, but the response of blood pressure to TR caused by phenelzine or desipramine was enhanced markedly by pheniramine-treatment. From the above experimental results, it is thought that the pressor effect of NE and TR potentiated by pheniramine is similar to that of debrisoquin, i.e. the sensitization of effector cell, and that central action of pheniramine can not ruled out.