Hyeong Rok Kim

Chonnam National University, Gwangju, Gwangju, South Korea

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Publications (70)175.38 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: To examine the association between the number of lymph nodes retrieved and oncologic outcome after preoperative chemoradiation for rectal cancer according to tumor regression grade.
    Annals of Surgical Oncology 11/2014; · 4.12 Impact Factor
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    ABSTRACT: The aim of this study is to investigate the clinicopathologic features and oncologic outcomes of colorectal cancer patients with extremely elevated (≥50 ng/mL) preoperative serum carcinoembryonic antigen (CEA) levels.
    International Journal of Colorectal Disease 11/2014; · 2.24 Impact Factor
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    ABSTRACT: Background Experience in terms of surgical case numbers required to develop proficiency for oncologic adequacy after sphincter-saving laparoscopic rectal cancer surgery has not been established.Method Three hundred seventeen consecutive patients underwent sphincter-saving laparoscopic rectal cancer surgery with curative intent performed by single surgeon. The learning curve was estimated using risk-adjusted cumulative sum (RA-CUSUM) and the graph of 195 consecutive patients who were treated by another surgeon was used to evaluate inter-surgeon variability in the learning curve.ResultsOverall, the 3-year local recurrence rate was 7.7% (95% confidence interval [CI], 6.4%–9.0%). The RA-CUSUM analysis demonstrated a learning curve of 110 cases for local recurrence for both of surgeons and 50–70 cases for CRM involvement. The 3-year local recurrence-free rate was better during the experienced period than during the learning period (95.1% [95% CI, 91.6%–97.1%] vs. 89.5% [95% CI, 84.4%–93.0%]; P = 0.029). These differences were obvious in subgroup analysis of stage III tumors (93.4% [95% CI, 86.6%–96.8%] vs. 78.6% [95% CI, 68.5%–85.3%]; P = 0.013).Conclusions Local recurrence rates decreased with increasing surgeon experience, as did other short-term outcomes, especially in advanced disease cases. J. Surg. Oncol. © 2014 Wiley Periodicals, Inc.
    Journal of Surgical Oncology 10/2014; · 2.64 Impact Factor
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    ABSTRACT: The aim of this study was to compare the restaging accuracy of repeat fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) scan with pelvic magnetic resonance imaging (MRI) in patients with rectal cancer who have undergone preoperative chemoradiation.
    Journal of Cancer Research and Clinical Oncology 09/2014; · 2.91 Impact Factor
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    Sang Woo Lim, Hyeong Rok Kim, Young Jin Kim
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    ABSTRACT: The aim of this retrospective study was to evaluate the feasibility of single incision laparoscopic surgery (SILS), and to compare the short-term surgical outcomes with those of conventional laparoscopic surgery for colorectal cancer.
    Annals of surgical treatment and research. 09/2014; 87(3):131-8.
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    ABSTRACT: Chest computed tomographic (CT) scans frequently detect indeterminate pulmonary nodules (IPNs) in patients with colorectal cancer. The discovery of such nodules creates a clinical dilemma.
    Annals of surgery. 08/2014;
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    ABSTRACT: Abstract Background: Early postoperative small bowel obstruction is associated with considerable morbidity and mortality but has not been well documented in the era of laparoscopic surgery for colorectal cancer.
    Journal of laparoendoscopic & advanced surgical techniques. Part A. 08/2014; 24(8):543-9.
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    ABSTRACT: Lymph node metastasis is the most important prognostic indicator for colon cancer patients. We compared the prognostic significance of the number of lymph node metastases (LNN) and the distribution of lymph node metastases (LND). A total of 187 patients underwent curative resection for stage III right-sided colon cancer between 2000 and 2010. We evaluated the oncologic outcomes according to LNN (N1 1-3, N2 4-6, N3 >6) and LND (LND1 metastases in pericolic nodes, LND2 metastases along the major vessels, N3 metastases around the origin of a main artery). A Cox proportional hazards model, with backward stepwise analysis was used to determine the effects of covariates on 5-year, disease-free survival (DFS) and 5-year overall survival (OS). Akaike's information criterion (AIC), and Harrell's concordance index (C-index) were compared for each developed model. During the median follow-up of 42.2 months, 5-year DFS and OS were 68 and 79.3 %, respectively. Multivariate analysis showed that both LNN and LND3 were independent prognostic factor for both 5-year DFS and OS. However, the prognostic model incorporating number of LNM was more precise than that of LND, with a lower AIC (5-year DFS, 554.2 vs. 566.9; 5-year OS, 318.1 vs. 337.9) and higher C-index (5-year DFS, 0.706 vs. 0.667; 5-year OS, 0.778 vs. 0.743). Our results show that the staging system incorporating LNN predicted prognosis better than LND.
    Annals of Surgical Oncology 12/2013; · 4.12 Impact Factor
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    ABSTRACT: The oncologic impact of anastomotic leakage after rectal cancer surgery remains controversial. Between January 1999 and December 2010, 1,148 patients with rectal cancer who underwent curative surgery with sphincter preservation were retrospectively reviewed. Using the propensity score matching method, 328 patients with fibrin glue were matched to 328 patients without fibrin glue, and oncologic outcomes were compared in the matched groups. Anastomotic leakage was diagnosed in 76 patients (6.6%). On multivariate analysis, fibrin glue was the independent predictor of prevention of anastomotic leakage. In the 656 matched groups, patients with anastomotic leakage had significantly worse 5-year local recurrence-free survival and disease-free survival than those without leakage. Multivariate analysis confirmed that anastomotic leakage was an independent prognostic factor of both local recurrence and disease-free survival, but the use of fibrin glue was not associated with the long-term outcomes when controlling for confounders. Anastomotic leakage is a major independent prognostic factor for long-term outcomes. Fibrin glue has a protective effect of anastomosis, without oncologic advantages.
    American journal of surgery 11/2013; · 2.36 Impact Factor
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    ABSTRACT: The aim of this study was to investigate the clinical outcomes after gamma knife surgery (GKS) or surgery as the first treatment for brain metastases in colorectal cancer (CRC). Of the 4350 patients diagnosed with CRC at our institution identified from 1987 to 2009, 27 patients who underwent GKS (GKS group) and 11 who underwent surgery (surgery group) were included. The oncologic outcomes were compared between the two groups. Local control was significantly better in the surgery group than in the GKS group (90% versus [vs.] 71.4%, respectively; p=0.006). The rate of symptom relief after 3months was significantly higher in the surgery group than in the GKS group (72.7 vs.18.5%, respectively; p=0.005). The median survival after GKS was 5.6months and surgery was 16.2months. In multivariate analysis, controlled primary tumor (p=0.038) and solitary metastasis (p=0.028) were correlated with prolonged overall survival, whereas surgery (p=0.034) was associated with longer local control. Surgery for brain metastasis from CRC is more advantageous in local control and neurologic symptom palliation than GSK. In multivariate analysis, overall survival was associated with controlled primary tumor and solitary metastasis.
    Journal of Clinical Neuroscience 08/2013; · 1.25 Impact Factor
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    ABSTRACT: This study was designed to evaluate the prognostic significance of the positivity of lymphovascular (LVI) and perineural invasion (PNI) in patients with locally advanced colorectal cancer. From January 1999 to December 2009, 1,437 consecutive patients who underwent curative surgery for stage II or III colorectal cancer were analyzed. Patients were then categorized into 4 groups: LVI-/PNI- (n = 850), LVI+ only (n = 178), PNI+ only (n = 271), and LVI+/PNI+ (n = 138). With a median follow-up period of 56 months, the 5-year overall survival rates of patients with LVI-/PNI-, LVI+ only, PNI+ only, and LVI+/PNI+ were 82%, 73%, 71%, and 56%, respectively (P < .001), and the 5-year disease-free survival rates of patients with LVI-/PNI-, LVI+ only, PNI+ only, and LVI+/PNI+ were 80%, 70%, 65%, and 46%, respectively (P < .001). In multivariate analysis, LVI+/PNI+ was an independent prognostic factor for both overall survival (P < .001) and disease-free survival (P < .001). Positivity of both LVI and PNI is a strong predictor of overall and disease-free survival in patients with stages II and III colorectal cancer.
    American journal of surgery 07/2013; · 2.36 Impact Factor
  • Jung Wook Huh, Jae Hyuk Lee, Hyeong Rok Kim
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    ABSTRACT: This study evaluated the predictive value of a number of tissue biomarkers, including proliferating cell nuclear antigen, survivin, thymidine phosphorylase, thymidylate synthase, bax, p53, nuclear factor-kappa B, vascular endothelial growth factor, matrix metalloproteinase-2, matrix metalloproteinase-9, CD133, CD44, and cyclooxygenase-2 with regard to preoperative chemoradiation in rectal cancer. The ability to predict tumor response before treatment may significantly impact the selection of patients for preoperative chemoradiation therapy for rectal cancer. However, no definite predictive marker is known. Pretreatment biopsies from 123 patients who underwent preoperative chemoradiation were included. The mRNA levels of 13 biomarkers were analyzed by reverse transcriptase-polymerase chain reaction, with normalization relative to glyceraldehydes 3-phosphate dehydrogenase. Response to treatment was assessed by a 4-point tumor regression grade scale based on the ratio of fibrosis to residual cancer. Among the 13 markers, no significant correlations in terms of T downstaging, N downstaging, and tumor-node-metastasis downstaging were observed. On multiple logistic regression analysis, only CD44 expression was found to be significant independent predictive factors for tumor regression grade response [odds ratio, 4.694 (1.155, 17.741), P = 0.030]. CD44 mRNA expression was significantly associated with expressions of the remaining 12 markers (all P < 0.05). Among the 118 patients receiving radical resection, proliferating cell nuclear antigen was the only independent factor to predict pathologic node negative status [odds ratio, 4.328 (1.078, 12.536), P = 0.037]. Elevated CD44 mRNA levels in pretreatment biopsies might be predictive of poor tumor regression after preoperative chemoradiation in rectal cancer. Moreover, the proliferating cell nuclear antigen mRNA level might be predictive of nodal regression.
    Annals of surgery 06/2013; · 7.90 Impact Factor
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    ABSTRACT: PURPOSE: The aim of this study was to determine which clinicopathological factors influenced the long-term survival after potentially curative resection of colorectal cancer patients with a normal preoperative serum level of carcinoembryonic antigen (CEA). METHODS: A total of 1,732 patients who underwent curative surgery for primary nonmetastatic colorectal cancers from 1997 to 2009 were analyzed. Of these patients, 1,128 (65.1 %) had normal level of preoperative CEA (<5 ng/mL). The predicting factors for survival were analyzed. RESULTS: When the serum CEA cutoff value was set at 2.4 ng/mL (median value), the high CEA groups displayed a higher percentage of older patients, males, large-diameter tumors, advanced T and N categories, and positive perineural invasion, compared to the low CEA groups. Multivariate analysis revealed that age, T category, N category, number of lymph nodes retrieved, operative method, lymphovascular invasion, perineural invasion, postoperative chemotherapy, and preoperative serum CEA level ≥ 2.4 ng/mL were independent predictors for 5-year overall survival, while tumor location, tumor size, T category, N category, lymphovascular invasion, and perineural invasion were independent predictors for 5-year disease-free survival. CONCLUSIONS: Even if patients with colorectal cancer have a normal preoperative CEA before surgery, CEA may be useful for prognostic stratification using 2.4 ng/mL as the cutoff.
    Journal of Cancer Research and Clinical Oncology 06/2013; · 2.91 Impact Factor
  • Jung Wook Huh, Hyeong Rok Kim, Young Jin Kim
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    ABSTRACT: : The clinical pretreatment factors that accurately predict response to chemoradiation in rectal cancer are not currently known. : The aim of this study is to evaluate the clinical factors associated with a pathological complete response after preoperative chemoradiotherapy for rectal cancer. : This study is a retrospective review of prospectively collected data. : This study was conducted at a tertiary care hospital/referral center in South Korea. : From December 2000 to September 2011, a total of 391 consecutive patients with rectal cancer who underwent neoadjuvant chemoradiotherapy followed by radical surgery were identified. The treatment consisted of concurrent chemoradiation, which included preoperative 5-fluorouracil-based chemotherapy and pelvic radiation (median, 5040 cGy); this was followed 8 weeks later (median, 57 days) by surgery with curative intent. : The primary outcome measured was the clinicopathological comparison between pathological complete response (n = 57, 14.6%) and non-pathological complete response (n = 334, 85.4%) groups. : The pathological complete response groups had a higher percentage of noncircumferential tumors, nonmacroscopic ulceration, well differentiation, small tumor diameter, early clinical T stage, early clinical N stage, or low levels of pretreatment CEA than the non-pathological complete response group. In multivariate regression analysis, independent predictors of a higher pathological complete response rate were noncircumferentiality (p = 0.007; OR, 3.214), nonmacroscopic ulceration (p = 0.002; OR, 6.702), and low pretreatment CEA level (p = 0.004; OR, 2.656). Significant differences in the pathological complete response rate existed among the 4 risk stratification groups (p < 0.001). For the prediction of pathological complete response by the clinical risk score model, the sensitivity was 64.1% and the specificity was 73.7% (area under the curve, 0.706; p < 0.001). : This study was limited because it was a single-institution study with a small sample size. : Pretreatment clinical variables, including tumor circumferentiality, macroscopic ulceration, and CEA level, may be important determinants in achieving a pathological complete response.
    Diseases of the Colon & Rectum 06/2013; 56(6):698-703. · 3.34 Impact Factor
  • Jung Wook Huh, Hyeong Rok Kim, Young Jin Kim
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    ABSTRACT: BACKGROUND: The current study was performed to examine the prognostic role of 53 messenger ribonucleic acid (mRNA) expression in patients with colorectal cancer and analyze its relationship with the expression of CD44 and CD133 mRNA levels. STUDY DESIGN: We retrospectively reviewed 137 consecutive patients who underwent curative surgery for stage I to III colorectal cancer in 2006. Prognostic factors, including wild-type (wt) p53, cyclooxygenase-2, CD44, and CD133 mRNA levels, were determined using reverse transcriptase polymerase chain reaction and clinical outcomes were analyzed. RESULTS: Wild-type p53 mRNA expression was correlated with the expression of CD44 and CD133 mRNA (p = 0.005 and p = 0.013, respectively). With a median follow-up period of 64 months, the 5-year disease-free survival rate of patients with elevated wt-p53 mRNA expression was significantly higher than that of those patients with low levels of wt-p53 mRNA expression (84.9% and 67.6%, respectively; p = 0.014). A multivariate analysis identified 3 independent factors that substantially affected the disease-free survival: depth of tumor invasion, lymph node metastasis, and wt-p53 mRNA expression. The 5-year disease-free survival rate in patients with stage III or rectal tumors differed significantly between the low and high wt-p53 expression groups. In stage III cancers, high wt-p53 expression was associated with better survival than low wt-p53 expression in patients treated with adjuvant chemotherapy (p = 0.005). A significant association between combined p53/CD44 expression and survival was evident (p = 0.006). CONCLUSIONS: Expression of p53 mRNA is a useful predictor of survival in patients with stage III or rectal cancers, with a significant association with CD44 mRNA expression.
    Journal of the American College of Surgeons 04/2013; · 4.50 Impact Factor
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    ABSTRACT: PURPOSE: This study evaluated the prognostic value of early recurrence in patients who have undergone curative resection for colorectal cancer. METHODS: A total of 1,159 consecutive patients who underwent curative resection for non-metastatic colorectal cancer from December 1998 to December 2007 were reviewed. The predictive factors for early recurrence postoperatively and the prognostic factors were analyzed. RESULTS: Of the 1,159 patients, postoperative recurrence was identified in 280 (24.1 %) patients, and 96 (34.3 %) of the 280 patients with recurrence were designed as early recurrence (less than 1 year postoperatively). In multivariate analysis, tumor location, tumor diameter, number of retrieved lymph nodes, and lymphovascular invasion were the independent predictors for early recurrence. The early recurrence group had a significantly lower overall survival rate than that of the non-early recurrence group for both colon cancer (P < 0.001) and rectal cancer (P < 0.001). The overall survival rate for stage III tumors significantly differed between the early and non-early recurred patients (P < 0.001), whereas the rate did not differ between the patients with stage II tumors (P = 0.364). In multivariate analysis, early recurrence was an independent predictor for unfavorable overall survival. Moreover, differentiation, N category, and postoperative chemotherapy were the independent predictors for overall survival for the patients with both early and overall recurrence. CONCLUSION: Poor survival was associated with early postoperative recurrence for patients who underwent curative resection for colorectal cancer. The use of adjuvant chemotherapy prolonged the survival of patients, irrespective of the interval of recurrence.
    International Journal of Colorectal Disease 03/2013; · 2.24 Impact Factor
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    ABSTRACT: BACKGROUND: There are still concerns about the oncologic safety of stent insertion for colorectal cancer obstruction. This study investigated whether the use of stents as a bridge to surgery negatively affect the long-term outcome compared to curative surgery for left-sided colorectal cancer obstruction. METHODS: Between January 2004 and December 2009, patients with left-sided colorectal cancer obstruction without distant metastasis were retrospectively reviewed. Forty-three patients underwent radical resection after preoperative stent insertion (stent group), whereas 48 underwent emergency surgery with curative intent (surgery group). The short- and long-term outcomes between the two groups were compared. RESULTS: The stent and surgery groups had similar demographics. There were no significant differences in primary anastomosis, laparoscopic-assisted surgery, operation time, time until first defecation and oral intake after surgery, postoperative hospital stay, and reoperation. The stent group had an average hospital stay 7 days longer than the surgery group. During the median follow-up period of 48.1 months, the 5-year disease-free survival rates were not significantly different between the stent and surgery groups (47.2 vs. 48.9 %, respectively; p = 0.499). Overall, the 5-year survival rate was also similar in the two groups (70.4 vs. 76.4 %, respectively; p = 0.941). CONCLUSIONS: For left-sided colorectal cancer obstruction, stent insertion followed by surgery showed short-term advantages and similar oncologic outcomes compared to surgery without preoperative intervention. Stent insertion as a bridge to surgery is a safe and feasible treatment option for patients with colorectal cancer obstruction.
    Surgical Endoscopy 02/2013; · 3.43 Impact Factor
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    ABSTRACT: OBJECTIVE:: To assess the risk factors for clinical anastomotic leakage (AL) in patients undergoing laparoscopic surgery for rectal cancer. BACKGROUND:: Little data are available about risk factors for AL after laparoscopic rectal cancer resection. METHODS:: This was a retrospective analysis of 1609 patients with rectal cancer who had undergone laparoscopic surgery for rectal cancer with sphincter preservation. Clinical data related to AL were collected from 11 institutions. Univariate and multivariate analyses were performed to determine the risk factors for AL. RESULTS:: AL was noted in 101 (6.3%) of the patients. The leakage rate ranged from 2.0% to 10.3% for each hospital (P = 0.04). In patients without protective stomas (n = 1187), male sex [hazard ratio (HR), 3.468], advanced tumor stage (HR, 2.520), lower tumor level (HR, 2.418), preoperative chemoradiation (HR, 6.284), perioperative transfusion (HR, 10.705), and multiple firings of the linear stapler (HR, 6.181) were significantly associated with AL. Our theoretical model suggested that the HR for patients with 2 risk factors was significantly higher than that the HR for patients with no or only 1 risk factor. CONCLUSIONS:: Male sex, low anastomosis, preoperative chemoradiation, advanced tumor stage, perioperative bleeding, and multiple firings of the linear stapler increased the risk of AL after laparoscopic surgery for rectal cancer. A diverting stoma might be mandatory in patients with 2 or more of the risk factors identified in this analysis.
    Annals of surgery 01/2013; · 7.90 Impact Factor
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    ABSTRACT: AIM: Background adenoma (BGA) is defined as benign adenomatous tissue contiguous to resected carcinomas, and the absence of BGA in the tumour is considered a histologic criterion of de novo cancers. The present study aimed to identify the clinicopathologic characteristics of T1 colorectal cancer without BGA. METHOD: A retrospective review was carried out of prospectively collected data from two centers: National Cancer Center, Korea and Chonnam National University Hwasun Hospital. A total of 590 patients with T1 colorectal cancer (CRC) treated by endoscopic or surgical resection between January 2001 and August 2011 were enrolled. Details regarding gender, age, tumour location, endoscopic gross type, tumour size, depth of submucosal (SM) invasion, angiolymphatic invasion, tumour grade, budding and lymph node (LN) metastasis were evaluated with regard to the presence or absence of BGA RESULTS: BGA was absent in 197 (33.4%) patients. Tumour size < 20 mm, flat/depressed type, deep SM depth and tumour budding were associated with the absence of BGA in univariate and multivariate analyses (p < 0.05). In surgically resected patients, LN metastases were significantly associated with the absence of BGA (p = 0.022) CONCLUSIONS: T1 CRC without BGA presented several characteristics of small size (< 20 mm), flat/depressed type, deep SM depth (SM 2/3), LN metastasis and tumour budding. These results indicate that de novo cancers may have a more invasive potential. © 2013 The Authors. Colorectal Disease © 2013 The Association of Coloproctology of Great Britain and Ireland.
    Colorectal Disease 01/2013; · 2.08 Impact Factor
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    ABSTRACT: Purpose: The aim of this study was to evaluate long-term oncologic outcomes after concurrent chemoradiation treatment for anal cancer. Materials and Methods: Between January 1979 and December 2008, the records of 50 consecutive patients with anal cancer and who were treated by chemoradiation or radiation only with a curative intent were retrospectively reviewed. The oncologic outcomes and the risk factors for recurrence were analyzed. Results: Of the 50 patients, 49 underwent concurrent chemoradiation and one underwent radiation only. After these definitive treatments, 43 (86.0%) achieved a clinical complete response. During the median follow-up of 60 months (range: 2-202 months), the 5-year overall survival, disease-free survival, and locoregional recurrence-free survival were 84.2%, 72.7%, and 69.9%, respectively. Multivariate analysis revealed that the performance status (p=0.031) and a clinical complete response (p=0.039) were the independent predictors for overall survival; lymph node involvement (p=0.031) was the only independent predictor for disease-free survival. Conclusion: The performance status and a clinical complete response may be reliable predictors of survival after chemoradiation for anal cancer. The addition of irradiation to the inguinal area may not be significantly associated with the outcomes.
    Yonsei medical journal 01/2013; 54(1):108-15. · 0.77 Impact Factor

Publication Stats

463 Citations
175.38 Total Impact Points

Institutions

  • 2009–2014
    • Chonnam National University
      • Department of Surgery
      Gwangju, Gwangju, South Korea
  • 2002–2014
    • Chonnam National University Hospital
      Sŏul, Seoul, South Korea
  • 2013
    • Sungkyunkwan University
      • Department of Surgery
      Sŏul, Seoul, South Korea
    • National Cancer Center Korea
      • Colorectal Cancer Branch
      Goyang, Gyeonggi, South Korea