Hwan Namgung
Dankook University
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Featured researches published by Hwan Namgung.
Journal of The Korean Surgical Society | 2012
Eui Tae Kim; Hwan Namgung; Hyun Deok Shin; Soon Il Lee; Jee Eun Kwon; Myung Chul Chang; Dong Guk Park
Purpose The aim of this study was to investigate the incidence and spectrum of malignant tumors in Korean neurofibromatosis type 1 (NF1) patients. Methods We retrospectively reviewed 125 patients who were diagnosed with NF1 at a single institution from 1995 to 2010. The incidence, location, histologic type, and radiologic findings of malignant tumors as well as development of multiple primary tumors were analyzed. Results Eighteen malignant tumors occurred in 16 patients (12.8%) among 125 Korean NF1 patients; 9 carcinomas, 8 sarcomas and 1 central nervous system (CNS) tumor. Five tumors were of nervous system origin and 13 were non-nervous system tumors. The locations of the tumors were as follow: 1 CNS, 2 lung, 3 breast, 3 stomach, 3 small bowel, 1 colon, 1 liver, 1 uterus, 1 neck, and 2 in extremities. Three malignant peripheral nerve sheath tumors (MPNSTs) occurred at the neck and extremity, and one in the liver. All three gastrointestinal stromal tumors (GISTs) had multiple tumors in the jejunum, and one MPNST and one pheochromocytoma were accompanied in two GISTs. Multiple primary tumors, benign or malignant were reported in 4 patients (25.0%), synchronously or metachronously. Conclusion Korean NF1 patients had a high risk of developing malignant tumors. The common malignant tumors in Koreans such as breast, lung and stomach cancers developed frequently in addition to the NF1-related tumors such as MPNST or GIST.
Journal of The Korean Surgical Society | 2013
Ji Yeon Kim; Jin Soo Kim; Moo Jun Baek; Chang Nam Kim; Won Jun Choi; Dong Kook Park; Hwan Namgung; Sang Chul Lee; Sang-Jeon Lee
Purpose This study evaluated the efficacy of neoadjuvant chemotherapy combining 5-flurouracil/folinic acid with irinotecan (FOLFIRI) in colorectal multiple liver metastases regardless of resectability. Methods Forty-four patients with multiple (at least two) colorectal liver metastases were enrolled at seven tertiary referral hospitals between May 2007 and September 2010. All patients received the FOLFIRI chemotherapeutic regimen. Response to chemotherapy was assessed after three cycles (6 weeks) and once more after six cycles (12 weeks) of treatment. Results Objective response was noted in 27 patients (61.4%) and 4 patients (9.1%) had progressive disease. Of 44 patients, 10 patients (22.7%) underwent curative surgery (R0 resection) and 34 patients did not receive R0 resection. Grades 3 to 4 hematological toxicity was noted in 12 patients (27.3%) and grades 3 to 4 nonhematologic toxicity was identified in 5 patients (11.4%). Conclusion FOLFIRI chemotherapy as a neoadjuvant chemotherapy for multiple colorectal liver metastases regardless of resectability demonstrated the possibility of R0 resection, high rate of objective response, and tolerable toxicities in this study.
Journal of The Korean Surgical Society | 2011
Hwan Namgung
Multiple jejunalgastrointestinal stromal tumors (GISTs) were found in a 52-year-old woman with a history of neurofibromatosis type 1. These tumors were composed of interlacing fascicles of uniform spindle cells with eosinophilic cytoplasm. Immunohistochemically, the tumor cells were positive for CD117, CD34 and negative for S-100, smooth muscle actin. Molecular analysis for activating mutations of KIT and PDGFRA was performed in two tumors. Contrary to sporadic GISTs, the NF1-associated GISTs are characterized by rare mutations of KIT or PDGFRA. But, one missense point mutation (Trp557Gly) was identified in KIT exon 11 of the extramural portion of the largest tumor in this case. The intramural portion of the largest tumor and the other tumor had wild type KIT and PDGFRA.
Journal of The Korean Surgical Society | 2016
Min Hyeong Jo; Jung Wook Suh; Jeong Seok Yun; Hwan Namgung; Dong-Guk Park
Purpose The purpose of this study was to examine 2-year follow-up results of cytoreductive surgery (CRS) and intraperitoneal chemotherapy (IPC) for peritoneal carcinomatosis (PC) of colorectal cancer. Methods We performed 54 cases of CRS and IPC in 53 patients with PC of colorectal cancer from December 2011 to December 2013. We collected data prospectively and analyzed the grade of PC, morbidity and mortality, and short-term follow-up (median, 10 months; range, 2–47 months) results. Results Mean peritoneal cancer index (PCI) was 15 (range, 1–35), and complete cytoreduction was possible in 35 patients (64.8%). Complications occurred in 25 patients (46.3%) and mortality occurred in 4 patients (7.4%). Excluding the 4 mortalities, 17 patients out of 49 patients (31.5%) were alive at the time of the last follow-up and the overall median survival was 10.3 months. Patients with complete cytoreduction had a median survival of 22.6 months, which was significantly longer than the median survival of 3.5 months for patients without complete cytoreduction (P < 0.001). PCI grade, CCR grade, cell type, and postoperative chemotherapy were significant prognostic factors by univariate analysis. Positive independent prognostic factors by multivariate analysis included PCI grade and postoperative chemotherapy. Conclusion CRS and IPC increased the survival of patients with low PCI and postoperative systemic chemotherapy was mandatory. However, this combined therapeutic approach showed high rate of complications and mortality. Therefore, this aggressive treatment should be performed in only selected patients by considering the general condition of the patient and the extent of PC.
Journal of The Korean Surgical Society | 2014
Kil Hwan Kim; Hwan Namgung; Dong Guk Park
Purpose Adult intussusception is uncommon, but an organic lesion is found to be the lead point in 75% to 90% of the cases. This study was designed to review our experience with adult intussusception and to determine if there are any preoperative predictive factors for a malignant lead point. Methods Thirty-three patients over 15 years of age were diagnosed with intussusceptions through operative finding over a period of 20 years. We reviewed the medical records of these patients retrospectively, and preoperative predictive factors of malignant lead points were analyzed. Results The preoperative diagnosis of intussusception had been made correctly in 86% of the cases, and computed tomography could find a lead point in 79%. A causative organic lesion was found in 29 patients (88%) pathologically; 16 cases (48%) were due to benign tumors, and 13 (39%) were due to malignant tumors. A malignant lead point was present in four of 21 enteric (20%) versus nine of 13 colonic intussusceptions (75%). The period from symptom appearance to hospital visit showed a more chronic nature in malignant neoplasm than in benign neoplasm (P = 0.006), and the location of causative organic lesion showed significant difference between benign and malignant groups (P = 0.003). Conclusion Adult intussusceptions are commonly secondary to a pathologic lead point, and a computed tomography is an effective diagnostic tool for finding a lead point preoperatively. The chronic nature of the disease presentation and colonic location of the lead point may suggest a malignant neoplasm.
Journal of The Korean Society of Coloproctology | 2015
Sang Il Youn; Hwan Namgung; Jeong Seok Yun; Yun Jun Park; Dong-Guk Park
We report a case of a goblet-cell carcinoid tumor of the appendix which metastasized to the peritoneum and was treated by using cytoreductive surgery (CRS) with intraperitoneal chemotherapy. A 47-year-old male presented with chronic constipation and was diagnosed as having a rectal adenocarcinoma with a signet-ring-cell component under colonoscopy. Computed tomography suggested peritoneal metastases with diffuse nodular parietal peritoneal thickening of the entire abdomen and focal invasion of the upper rectum by a seeding mass. CRS with intraperitoneal chemotherapy was done under the diagnosis of a rectal adenocarcinoma with peritoneal metastases. The pathologic diagnosis was a goblet-cell carcinoid tumor of the appendix with peritoneal metastasis. The histological discrepancy between a peritoneal metastatic mass and a rectal mass was due to the mixed histological pattern of a goblet-cell carcinoid tumor. A metastatic mass may not share identical immunohistochemical characteristics from its origin. This histologic discrepancy necessitates caution in diagnosing a distant metastasis of a goblet-cell carcinoid tumor.
Journal of The Korean Society of Coloproctology | 2017
Jung Wook Suh; Jun Won Min; Hwan Namgung; Dong-Guk Park
We report a case of urinary bladder perforation during colonoscopy. A 67-year-old female, who had undergone a transabdominal hysterectomy for uterine myomas 15 years ago, visited the emergency department with complaint of abdominal pain after a screening colonoscopy. Laparoscopic examination revealed severe adhesion between the sigmoid colon and the urinary bladder. The urinary bladder wall was weakened, and several perforation sites were found. The surgery was converted to a laparotomy. After a thorough examination, we performed primary repair for the perforation sites, followed by an omentopexy.
Journal of The Korean Society of Coloproctology | 2015
Jeong Rye Kim; Bong Man Kim; You Me Kim; Won Ae Lee; Hwan Namgung
We report a case of colonic metastasis from ovarian cancer presented as an intraluminal fungating mass mimicking primary colon cancer 8 years after surgery for ovarian cancer. A 70-year-old woman presented with constipation. She had undergone an extended total abdominal hysterectomy with bilateral salpingo-oophorectomy for an ovarian papillary serous cystadenocarcinoma 8 years earlier. Colonoscopy showed a large fungating mass 10 cm from the anal verge that was suspected to be colorectal cancer. A computed tomography scan showed a bulky intraluminal fungating mass in the rectosigmoid junction. After a lower anterior resection and a pathologic diagnosis, a diagnosis of a papillary serous adenocarcinoma due to metastasis from an ovarian tumor was made for this patient.
Journal of The Korean Society of Coloproctology | 2004
Sang-On Yun; Hwan Namgung; Chang-Hwan Lee; Dong-Guk Park
Journal of The Korean Surgical Society | 2014
Jin Soo Kim; Ji Yeon Kim; Sang-Jeon Lee; Dong Kook Park; Hwan Namgung; Chang Nam Kim; Won Jun Choi; Moo Jun Baek