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Featured researches published by Eu-Chang Hwang.


Annals of Nuclear Medicine | 2013

Is further evaluation needed for incidental focal uptake in the prostate in 18-fluoro-2-deoxyglucose positron emission tomography–computed tomography images?

Insang Hwang; Ari Chong; Seung-Il Jung; Eu-Chang Hwang; Sun-Ouck Kim; Taek-Won Kang; Dongdeuk Kwon; Kwangsung Park; Soo-Bang Ryu

ObjectiveThe aim of this study was to investigate the frequency of secondary evaluation to detect prostate cancer that was primarily manifested as abnormal hypermetabolism detected by 18-fluoro-2-deoxyglucose (FDG) positron emission tomography–computed tomography (PET/CT). We also evaluated the association of maximum standardized uptake values (SUVmax) on PET/CT with clinicopathologic results.Materials and methodsWe evaluated PET/CT reports from a total of 12,037 patients to find cases with abnormal prostate hypermetabolism. Patients with known prostate cancer or a recent prostate procedure were excluded. We analyzed the frequency of secondary evaluations such as digital rectal exams (DRE), levels of serum prostate-specific antigen (PSA), and/or biopsy to confirm prostate cancer. Biopsied patients were categorized into benign and cancer groups. Clinicopathologic characteristics were compared between the groups.ResultsAmong 12,037 PET/CT images, 184 (1.5xa0%) showed abnormal hypermetabolism in the prostate. Secondary evaluation was carried out in 120 patients. Biopsy was performed in 38 patients and prostate cancer was confirmed in 23 patients. The median serum PSA level was 3.2 and 49.7xa0ng/mL in the benign group and cancer group, respectively. The SUVmax was higher in the cancer group (5.7xa0±xa05.1) than in the benign group (4.8xa0±xa02.7), but the difference was not statistically significant (pxa0=xa00.37). In the cancer group, a high serum PSA level (≥20xa0ng/mL) was detected in 78.3xa0% of the patients. The Gleason score was 7 in 34.7xa0% and 8–10 in 56.5xa0% of prostate cancer patients.ConclusionsHypermetabolism in the prostate was incidentally detected in 1.5xa0% of patients, and only 65.2xa0% of these patients underwent further evaluation (DRE and/or serum PSA levels). Among cases of incidentally detected hypermetabolism in the prostate, patients with abnormal findings (DRE and/or PSA levels) showed high positivity by biopsy, and more than two-thirds of the positive biopsies showed significant prostate cancer. Therefore, patients with hypermetabolism in the prostate should not be ignored and should be secondarily evaluated by DRE and PSA level.


Chonnam Medical Journal | 2012

Expression and Localization of Aquaporins in Benign Prostate Hyperplasia and Prostate Cancer

Insang Hwang; Seung-Il Jung; Eu-Chang Hwang; Seung Hee Song; Hyun-Suk Lee; Sun-Ouck Kim; Taek-Won Kang; Dongdeuk Kwon; Kwangsung Park

The aquaporin (AQP) families of water channels are intrinsic membrane proteins that facilitate selective water and small solute movement across the plasma membrane. The purposes of this study were to determine the expression and localization of AQPs in benign prostatic hyperplasia and prostate cancer. Prostatic tissue was collected from patients with benign prostatic hyperplasia or prostate cancer by transurethral resection of the prostate. The expression and cellular localization of the AQPs were determined in the human prostate by Western blot and immunohistochemistry. AQP1, 3, and 9 were expressed in the human prostate. Western blot analysis revealed bands at 28-36 kDa for the AQP1, 3, and 9 proteins. Of these proteins, AQP3 and 9 were expressed in the epithelium. Immunolabeling showed that AQP1 was mainly expressed in the capillaries and venules of the prostate, AQP9 was expressed in the cytoplasm of the epithelium, and AQP3 was mainly associated with the plasma membrane of the prostatic epithelium. Only AQP3 expression was localized in the cell membrane, and expressed AQP3 was translocated to the cytoplasm in prostate cancer. The epithelium in the human prostate expresses AQP3 and 9 proteins, and the capillaries and venules of the prostate express AQP1. Characterizing or modifying the expression of AQP3 may lead to an understanding of the role of the AQPs in human prostatic disease.


Asian Journal of Andrology | 2010

Prostate calculi in cancer and BPH in a cohort of Korean men: presence of calculi did not correlate with cancer risk.

Eu-Chang Hwang; Hyang-Sik Choi; Chang-Min Im; Seung-Il Jung; Sun-Ouck Kim; Taek-Won Kang; Dongdeuk Kwon; Kwangsung Park; Soo-Bang Ryu

Prostatic calculi are common and are associated with inflammation of the prostate. Recently, it has been suggested that this inflammation may be associated with prostate carcinogenesis. The aim of this study was to investigate the relationship between prostatic calculi and prostate cancer (PCa) in prostate biopsy specimens. We retrospectively analyzed 417 consecutive patients who underwent transrectal ultrasonography (TRUS) and prostate biopsies between January 2005 and January 2008. Based on the biopsy findings, patients were divided into benign prostatic hyperplasia and PCa groups. TRUS was used to detect prostatic calculi and to measure prostate volume. The correlations between PCa risk and age, serum total PSA levels, prostate volume, and prostatic calculi were analyzed. Patient age and PSA, as well as the frequency of prostatic calculi in the biopsy specimens, differed significantly between both the groups (P < 0.05). In the PCa group, the Gleason scores (GSs) were higher in patients with prostatic calculi than in patients without prostatic calculi (P = 0.023). Using multivariate logistic regression analysis, we found that patient age, serum total PSA and prostate volume were risk factors for PCa (P = 0.001), but that the presence of prostatic calculi was not associated with an increased risk of PCa (P = 0.13). In conclusion, although the presence of prostatic calculi was not shown to be a risk factor for PCa, prostatic calculi were more common in patients with PCa and were associated with a higher GS among these men.


International Neurourology Journal | 2010

The Expression of AQP1 and eNOS in Menopausal Rat Urinary Bladder

Sun-Ouck Kim; Seung-Hee Song; Eu-Chang Hwang; Kwangsung Park; Dongdeuk Kwon; Kyu-Youn Ahn; Dong-Hee Kim; Soo-Bang Ryu

PURPOSEnAquaporins (AQPs) have been reported to be expressed in rat and human urothelium. Nitric oxide (NO) is thought to play an important role in the bladder overactivity related to menopause. The purpose of this study was to investigate the effect of hormonal alteration on the expression of AQP1 and eNOS in menopausal rat urinary bladder.nnnMATERIALS AND METHODSnFemale Sprague-Dawley rats (230-240 g, N=30) were divided into three groups: control (N=10), bilateral ovariectomy (Ovx, N=10), and bilateral ovariectomy followed by subcutaneous injections of 17β-estradiol (50 mg/kg/day, Ovx+Est, N=10). After 4 weeks, urodynamic studies measuring the contraction interval and contraction pressure were done. The expression and cellular localization of AQP1 and eNOS were determined by performing Western blotting and immunohistochemistry on the rat urinary bladder.nnnRESULTSnThe approximate contraction interval (min) was significantly decreased in the Ovx group (3.9±0.25) compared to the control group (6.7±0.15), and was increased after estrogen treatment (9.7±0.22) (p<0.05). The AQP1 and eNOS immunoreactivities were localized in the same areas: capillaries, arterioles, and venules of the lamina propria. The protein expression of AQP1 was not changed significantly, whereas eNOS expression was significantly decreased in the Ovx group and restored to the control value in the Ovx+Est group.nnnCONCLUSIONSnThis study showed that ovariectomy causes a significant change in e-NOS expression without a change in AQP1 in menopausal rat urinary bladder. This may imply that e-NOS has a functional role in the bladder overactivity that occurs in association with menopause.


Scandinavian Journal of Immunology | 2013

Generation of Potent Cytotoxic T Lymphocytes Against Castration‐Resistant Prostate Cancer Cells by Dendritic Cells Loaded With Dying Allogeneic Prostate Cancer Cells

Eu-Chang Hwang; Mi-Seon Lim; C.-M. Im; Dongdeuk Kwon; Hyun-Ju Lee; Thanh-Nhan Nguyen-Pham; Y.-K. Lee; Je-Jung Lee

To induce a potent cytotoxic T lymphocyte (CTL) response in dendritic cell (DC)‐based immunotherapy against prostate cancer, various tumour antigens should be loaded onto DCs. The aim of this study was to establish a method of immunotherapy for castration‐resistant prostate cancer (CRPC) using prostate cancer–specific CTLs generated in vitro by DCs. Monocyte‐derived DCs from patients with CRPC were induced to mature using a standard cytokine cocktail (in IL‐1β, TNF‐α, IL‐6 and PGE2: standard DCs, sDCs) or using an α‐type 1‐polarized DC (αDC1) cocktail (in IL‐1β, TNF‐α, IFN‐α, IFN‐γ and polyinosinic:polycytidylic acid) and loaded with the UVB‐irradiated CRPC cell line PC‐3. Antigen‐loaded DCs were evaluated by morphological and functional assays. The αDC1s significantly increased the expression of several molecules related to DC maturation, regardless of whether the αDC1s were loaded with tumour antigens or not, compared to sDCs. The αDC1s showed a higher production of interleukin‐12 both during maturation and after subsequent stimulation with CD40L, which was not significantly affected by loading with tumour antigens, as compared to standard DCs (sDCs). Prostate cancer–specific CTLs against autologous CRPC cells were successfully induced by αDC1s loaded with dying PC‐3 cells. Autologous αDC1s loaded with an allogeneic CRPC cell line can generate greater CRPC‐specific CTL responses as compared to sDCs and may provide a novel source of DC‐based vaccines that can be used for the development of immunotherapy in patients with CRPC.


International Urology and Nephrology | 2013

A preliminary study of the variability in location of the ureteral orifices with bladder filling by fluoroscopic guidance: the gender difference.

Insang Hwang; Sun-Ouck Kim; Ho-Song Yu; Eu-Chang Hwang; Seung-Il Jung; Taek-Won Kang; Dongdeuk Kwon; Kwangsung Park

Background and purposeTo determine landmarks for stent positioning in both ureteral orifices (UOs) and the gender differences in their location in men and women.Patients and methodsThe location of the UO and the bladder neck (BN) was measured fluoroscopically by the intravesical distal location of an open-ended catheter marked with radiopaque materials. We compared the location in men (nxa0=xa012) and women (nxa0=xa012) with a full bladder (hydrostatic pressure of 50 cmH2O) or an empty bladder.ResultsThe mean distances from BN to UO in men and women were significantly different both in an empty bladder (2.5xa0±xa00.4 and 2.1xa0±xa00.3xa0cm, respectively) and in a full bladder (2.9xa0±xa01.0 and 2.3xa0±xa00.6xa0cm, respectively). The location of UO was changed by bladder filling in women but not in men. In women, most UOs were found superior to the symphysis pubis (SP) in empty bladder (66.6xa0%). Most of this location was observed at behind the upper boarder of SP in full bladder of women (75xa0%). The BN of women was located at the lower level in basal state compared to men. Also, the location of BN was markedly changed by bladder fulling in women (pxa0=xa00.04) but not in men.ConclusionsSignificant gender differences were observed in the location of UO and BN. Clinicians should keep in mind the anatomical differences between men and women during fluoroscopic-guided procedure.


Urology | 2010

UP-1.26: The role of alpha 1(A) Adrenoceptor antagonist tamsulosin for the treatment of patients with lower urinary tract symptoms in women: the effect of nocturia and sleep quality

Soo-Bang Ryu; Sun-Ouck Kim; Eu-Chang Hwang; Chang Min Im; Kyung-Jin Oh; S. Jung; T.W. Kang; Dongdeuk Kwon; Kwangsung Park


Urology | 2011

UP-03.145 T2 Ureteral Tumor and Severe Hydronephrosis: Poor Prognostic Factors in Upper Urinary Tract Transitional Cell Carcinoma

Eu-Chang Hwang; S. Jung; T.W. Kang; Dongdeuk Kwon; Kwangsung Park; Soo-Bang Ryu


Urology | 2011

UP-02.088 Alpha-Type 1 Polarized Dendritic Cells Loaded with Apoptotic Allogeneic Prostate Cancer Cells can Induce Potent Cytotoxic T Lymphocytes Against Prostate Cancer Cells

Eu-Chang Hwang; S. Jung; T.W. Kang; Dongdeuk Kwon; Kwangsung Park; Soo-Bang Ryu; M. Im; Jeong Seon Lee


Urology | 2010

UP-1.13: The efficacy and safety of combined therapy with tamsulosin and tolterodine for female patients with a maximal flow rate less than 12ml/sec

Sun-Ouck Kim; Eu-Chang Hwang; Chang Min Im; Kyung-Jin Oh; S. Jung; T.W. Kang; Dongdeuk Kwon; Kwangsung Park; Soo-Bang Ryu

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Dongdeuk Kwon

Chonnam National University

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Kwangsung Park

Chonnam National University

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Soo-Bang Ryu

Chonnam National University

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Sun-Ouck Kim

Chonnam National University

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S. Jung

Chonnam National University

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T.W. Kang

Chonnam National University

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Taek-Won Kang

Chonnam National University

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Seung-Il Jung

Chonnam National University

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Chang Min Im

Chonnam National University

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Insang Hwang

Chonnam National University

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