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Featured researches published by Ahwon Lee.


Journal of Clinical Oncology | 2011

Estrogen Receptor (ESR1) mRNA Expression and Benefit From Tamoxifen in the Treatment and Prevention of Estrogen Receptor–Positive Breast Cancer

Chungyeul Kim; Gong Tang; Katherine L. Pogue-Geile; Joseph P. Costantino; Frederick L. Baehner; Joffre Baker; Maureen T. Cronin; Drew Watson; Steven Shak; Olga L. Bohn; Debora Fumagalli; Yusuke Taniyama; Ahwon Lee; Megan L. Reilly; Victor G. Vogel; Worta McCaskill-Stevens; Leslie G. Ford; Charles E. Geyer; D. Lawrence Wickerham; Norman Wolmark; Soonmyung Paik

PURPOSE Several mechanisms have been proposed to explain tamoxifen resistance of estrogen receptor (ER) -positive tumors, but a clinically useful explanation for such resistance has not been described. Because the ER is the treatment target for tamoxifen, a linear association between ER expression levels and the degree of benefit from tamoxifen might be expected. However, such an association has never been demonstrated with conventional clinical ER assays, and the ER is currently used clinically as a dichotomous marker. We used gene expression profiling and ER protein assays to help elucidate molecular mechanism(s) responsible for tamoxifen resistance in breast tumors. PATIENTS AND METHODS We performed gene expression profiling of paraffin-embedded tumors from National Surgical Adjuvant Breast and Bowel Project (NSABP) trials that tested the worth of tamoxifen as an adjuvant systemic therapy (B-14) and as a preventive agent (P-1). This was a retrospective subset analysis based on available materials. RESULTS In B-14, ESR1 was the strongest linear predictor of tamoxifen benefit among 16 genes examined, including PGR and ERBB2. On the basis of these data, we hypothesized that, in the P-1 trial, a lower level of ESR1 mRNA in the tamoxifen arm was the main difference between the two study arms. Only ESR1 was downregulated by more than two-fold in ER-positive cancer events in the tamoxifen arm (P < .001). Tamoxifen did not prevent ER-positive tumors with low levels of ESR1 expression. CONCLUSION These data suggest that low-level expression of ESR1 is a determinant of tamoxifen resistance in ER-positive breast cancer. Strategies should be developed to identify, treat, and prevent such tumors.


Radiographics | 2009

MR Imaging Findings of Hydrosalpinx : A Comprehensive Review

Mi Young Kim; Sung Eun Rha; Soon Nam Oh; Seung Eun Jung; Young Joon Lee; You Sung Kim; Jae Young Byun; Ahwon Lee; Mee-Ran Kim

Hydrosalpinx is a common adnexal lesion that may occur either in isolation or as a component of a complex pathologic process (eg, pelvic inflammatory disease, endometriosis, fallopian tube tumor, or tubal pregnancy) that leads to distal tubal occlusion. On magnetic resonance (MR) images, hydrosalpinx appears as a fluid-filled C- or S-shaped tubular structure that arises from the upper lateral margin of the uterus. Although hydrosalpinx is most often seen on ultrasonographic images, it also may be delineated on multiplanar MR images. MR imaging also may be useful for determining the cause of a hydrosalpinx or its associated adnexal process by characterizing the nature of the contents of the dilated tube. Tubal fluid with high signal intensity on T1-weighted images is suggestive of hematosalpinx associated with endometriosis and tubal pregnancy. A thickened wall of a dilated fallopian tube that displays variable or heterogeneous signal intensity may be indicative of pyosalpinx as a component of a tubo-ovarian abscess. The presence of an enhancing solid mass within a dilated tube is suggestive of fallopian tube carcinoma, whereas enhancement of the dilated tubal wall surrounding a saclike cystic mass may be indicative of a tubal pregnancy. Understanding the pathogenesis and clinical manifestations of conditions associated with hydrosalpinx may aid in the timely diagnosis of complex adnexal masses at MR imaging, enabling avoidance of unnecessary procedures.


Journal of the National Cancer Institute | 2013

Predicting Degree of Benefit From Adjuvant Trastuzumab in NSABP Trial B-31

Katherine L. Pogue-Geile; Chungyeul Kim; Jong-Hyeon Jeong; Noriko Tanaka; Hanna Bandos; Patrick G. Gavin; Debora Fumagalli; Lynn C. Goldstein; Nour Sneige; Eike Burandt; Yusuke Taniyama; Olga L. Bohn; Ahwon Lee; Seung-Il Kim; Megan L. Reilly; Matthew Y. Remillard; Nicole L. Blackmon; Seong-Rim Kim; Zachary D. Horne; Priya Rastogi; Louis Fehrenbacher; Edward H. Romond; Sandra M. Swain; Eleftherios P. Mamounas; D. Lawrence Wickerham; Charles E. Geyer; Joseph P. Costantino; Norman Wolmark; Soonmyung Paik

BACKGROUND National Surgical Adjuvant Breast and Bowel Project (NSABP) trial B-31 suggested the efficacy of adjuvant trastuzumab, even in HER2-negative breast cancer. This finding prompted us to develop a predictive model for degree of benefit from trastuzumab using archived tumor blocks from B-31. METHODS Case subjects with tumor blocks were randomly divided into discovery (n = 588) and confirmation cohorts (n = 991). A predictive model was built from the discovery cohort through gene expression profiling of 462 genes with nCounter assay. A predefined cut point for the predictive model was tested in the confirmation cohort. Gene-by-treatment interaction was tested with Cox models, and correlations between variables were assessed with Spearman correlation. Principal component analysis was performed on the final set of selected genes. All statistical tests were two-sided. RESULTS Eight predictive genes associated with HER2 (ERBB2, c17orf37, GRB7) or ER (ESR1, NAT1, GATA3, CA12, IGF1R) were selected for model building. Three-dimensional subset treatment effect pattern plot using two principal components of these genes was used to identify a subset with no benefit from trastuzumab, characterized by intermediate-level ERBB2 and high-level ESR1 mRNA expression. In the confirmation set, the predefined cut points for this model classified patients into three subsets with differential benefit from trastuzumab with hazard ratios of 1.58 (95% confidence interval [CI] = 0.67 to 3.69; P = .29; n = 100), 0.60 (95% CI = 0.41 to 0.89; P = .01; n = 449), and 0.28 (95% CI = 0.20 to 0.41; P < .001; n = 442; P(interaction) between the model and trastuzumab < .001). CONCLUSIONS We developed a gene expression-based predictive model for degree of benefit from trastuzumab and demonstrated that HER2-negative tumors belong to the moderate benefit group, thus providing justification for testing trastuzumab in HER2-negative patients (NSABP B-47).


Japanese Journal of Clinical Oncology | 2009

p53 as a Specific Prognostic Factor in Triple-negative Breast Cancer

Byung Joo Chae; Ja Seong Bae; Ahwon Lee; Woo Chan Park; Young Jin Seo; Byung Joo Song; Jung Soo Kim; Sang Seol Jung

OBJECTIVE A recent suggestion is that the predictive value of a single biomarker may rely on the genetic background on the tumor and that different breast cancer subgroups may have different predictive markers of response to chemotherapy. The prognostic value of p53 in the outcome of adjuvant anthracycline-containing chemotherapy was evaluated according to molecular subclasses defined using the expression of estrogen receptor, progesterone receptor and human epidermal growth factor receptor 2. METHODS Subjects were patients (n = 135) with invasive ductal carcinoma treated with adjuvant anthracycline-based chemotherapy between 1994 and 2000 in our hospital. Clinico-pathological features were reviewed by retrospective examination of medical records. RESULTS Overall survival rate was not independently predictive by p53 status (P = 0.182). However, in triple-negative cases, there was statistically significant survival difference (P = 0.034) and no statistically significant difference (P = 0.783) in non-triple-negative cases by p53 status. In the Cox proportional hazard analysis, p53 was also strongly predictive for relapse-free survival (P = 0.013) and overall survival (P = 0.049) in triple-negative patients. CONCLUSIONS p53 status could be a specific prognostic factor in triple-negative breast cancer patients treated by adjuvant anthracycline-based regimen. When p53 is positive in triple-negative breast cancer, we could expect poor survival, prompting aggressive or alternative treatment.


Pathology International | 2006

Expression of transforming acidic coiled-coil containing protein 3 is a novel independent prognostic marker in non-small cell lung cancer

Chan Kwon Jung; Ji Han Jung; Gyeong Sin Park; Ahwon Lee; Chang Suk Kang; Kyo Young Lee

Transforming acidic coiled‐coil containing protein 3 (TACC3) is known to be involved in the control of normal cell growth and differentiation and in mechanisms of unregulated growth leading to tumorigenesis. The aim of the present paper was to determine the rate of TACC3 expression in a non‐small cell lung cancer (NSCLC) collection and to clarify its correlation with clinicopathological parameters. A total of 163 NSCLC were analyzed immunohistochemically using a polyclonal TACC3 antibody and monoclonal p53 and Ki‐67 antibodies on NSCLC tissue microarrays. A high level of TACC3 expression was observed in 14.8% of cases, preferentially squamous cell carcinomas. Patients whose tumors had a high TACC3 expression had a significantly shorter median survival time. In the Cox regression‐based multivariate analysis, TACC3 expression proved to be an independent prognostic parameter (P = 0.031). TACC3 expression was correlated with p53 expression, and patient whose tumors highly expressed TACC3 and p53 had a significantly poorer prognosis than patients whose tumors had low‐level expression for both immunostainings (P = 0.006). It is suggested that increase in TACC3 may impart a proliferative advantage to NSCLC and contribute to tumor progression, and that TACC3 expression is a strong prognostic indicator of clinical outcome in NSCLC.


Modern Pathology | 2008

Diagnostic use of nuclear β -catenin expression for the assessment of endometrial stromal tumors

Chan Kwon Jung; Ji-Han Jung; Ahwon Lee; Youn-Soo Lee; Yeong-Jin Choi; Seung-Kew Yoon; Kyo-Young Lee

Alterations in β-catenin degradation cause it to accumulate to immunohistochemically detectable levels in the nuclei of tumor cells. Although it has been shown that nuclear β-catenin immunostaining is useful for the diagnosis of some mesenchymal tumors, there is little known about β-catenin expression in endometrial stromal tumors. In this study, nuclear β-catenin immunoreactivity was evaluated in normal endometrium and endometrial mesenchymal tumors and then compared with that of CD10. The endometrial mesenchymal tumors evaluated included endometrial stromal nodules (n=2), low-grade endometrial stromal sarcomas (n=12), undifferentiated endometrial sarcomas (n=8) and uterine cellular leiomyomata (n=9). In addition, direct DNA sequencing of β-catenin exon 3 was conducted in 15 endometrial stromal tumors. Normal endometrial stromal cells showed strong cytoplasmic reactivity for CD10 but no detectable reactivity for β-catenin. Nuclear β-catenin immunoreactivity was detected in 11 low-grade endometrial stromal sarcomas (92%) and 6 undifferentiated endometrial sarcomas (75%). Ten low-grade endometrial stromal sarcomas (83%) and six undifferentiated endometrial sarcomas (75%) were positive for CD10. Eight low-grade endometrial stromal sarcomas (67%) exhibited diffuse, strong nuclear immunoreactivity with β-catenin, whereas only four cases (33%) expressed diffuse, strong immunoreactivity with CD10. All nine cases of uterine cellular leiomyomata were completely negative for both CD10 and β-catenin. β-catenin mutations were rare in endometrial stromal tumors. Taken together, these results indicate that nuclear β-catenin immunostaining can serve as a sensitive immunohistochemical marker for the diagnosis of endometrial stromal tumors and is useful for differentiating low-grade endometrial stromal sarcomas from uterine cellular leiomyomata.


Acta Cytologica | 2008

Split sample comparison of a liquid-based method and conventional smears in thyroid fine needle aspiration.

Chan Kwon Jung; Ahwon Lee; Eun-Sun Jung; Yeong-Jin Choi; So-Lyung Jung; Kyo-Young Lee

OBJECTIVE To compare the efficacy of the SurePath (SP) vs. conventional smears (CS) in fine needle aspiration (FNA) of thyroid gland lesions. STUDY DESIGN A total of 193 FNA cases with thyroid nodules were studied. Samples from ultrasound-guided FNA were split to prepare CS and SP slides. The diagnostic categories of unsatisfactory, benign, atypical and malignant were compared. Galectin-3 immunostaining was performed on SP slides. RESULTS Some differences were found between the cytomorphology of CS and SP. SP slides showed more increased cellularity and more clustered tissue fragments. On SP slides, nuclear detail and nucleoli were more easily detected and nuclear irregularity was very useful for the diagnosis of papillary carcinoma. SP showed a trend toward a lower proportion of atypical category. The overall sensitivity of FNA in diagnosing thyroid neoplasm was 90.9% for CS and 93.9% for SP. Most lesions (73%) diagnosed as papillary carcinoma after surgery showed positive staining of galectin-3. CONCLUSION The SP method showed easy evaluation of cytomorphologic features and consistent specimen quality and appeared to be more useful in diagnosing the suspicious cases. Moreover, it offered the possibility of adjunctive immunocytochemistry on the same sample.


Japanese Journal of Clinical Oncology | 2010

CK7, CK20, CDX2 and MUC2 Immunohistochemical Staining Used To Distinguish Metastatic Colorectal Carcinoma Involving Ovary from Primary Ovarian Mucinous Adenocarcinoma

Jung Ha Shin; Jeong Hoon Bae; Ahwon Lee; Chan Kwon Jung; Hyeon Woo Yim; Jong-Sup Park; Kyo-Young Lee

OBJECTIVE Colorectal adenocarcinoma, the most common tumor that metastasizes to the ovary, is often difficult to distinguish from primary ovarian mucinous adenocarcinoma (POMA). Obtaining the correct diagnosis is difficult but crucial to treatment and prognosis. METHODS We evaluated the immunohistochemical (IHC) expression of cytokeratin 7 (CK7), cytokeratin 20 (CK20), CDX2, CEA, MUC2, MUC5AC and alpha-methylacyl-CoA racemase (AMACR) in 22 POMAs and 41 metastatic colorectal adenocarcinomas (MCAOs) involving ovaries. RESULTS MCAOs, in contrast with POMAs, were almost always negative for MUC5 (97.6%), often negative for CK7 (82.9%), focal or diffuse positive for CDX2 (73.2%), diffuse positive for CK20 (65.9%), focal or diffuse positive for MUC2 (51.2%), diffuse positive for CEA (41.5%) and negative for AMACR (41.5%). We therefore considered CK7 (-), CK20 (diffuse +), CDX2 (+) and MUC2 (+) to be colonic markers and regarded cases with expression of more than two colonic markers as MCAO, those with no expression of colonic markers as POMA and those with expression of one colonic marker as indeterminate. Using CK7/CK20/CDX2/MUC2, 82.5% of the cases were correctly classified, 6.3% were misclassified and 6.3% were indeterminate. CONCLUSION CK7, CK20, CDX2 and MUC2 IHC staining is a useful adjunctive diagnostic tool to differentiate MCAOs from POMAs, in addition to clinical history and gross and microscopic findings.


Archives of Pathology & Laboratory Medicine | 2004

Detection of tumor markers including carcinoembryonic antigen, APC, and cyclin D2 in fine-needle aspiration fluid of breast

Ahwon Lee; Yonggoo Kim; Kyungja Han; Chang Suk Kang; Hae Myung Jeon; Sang In Shim

CONTEXT The traditional triple test for breast cancer diagnosis is physical examination, mammography, and aspiration cytology. However, the accuracy of mammography on young women with nonatrophied breasts is poor compared with that for women older than 50 years, and additional methods for diagnosis of breast cancer are needed. OBJECTIVE To investigate whether carcinoembryonic antigen (CEA), CA 15-3, and CA 125 concentrations in breast aspiration fluid are useful as breast cancer biochemical markers and whether APC and cyclin D2 gene promoter hypermethylation could be regarded as a breast cancer molecular marker. DESIGN CEA, CA 15-3, and CA 125 concentrations were measured, and methylation status of the APC gene promoter 1A and the promoter region of the cyclin D2 gene were analyzed using a methylation-specific polymerase chain reaction assay of ex vivo breast aspiration fluid obtained from 49 samples of excised breast tissue. SETTING The specimens were collected during a 1-year period in the tertiary care teaching hospital in Seoul, Korea. PATIENTS Forty-nine patients with breast masses were surgically treated. Thirty-four patients had breast cancer, and 15 had benign breast disease. RESULTS Aspiration fluid CEA concentrations were significantly higher in breast cancer cases than in cases of benign breast disease (mean, 69.90 ng/mg protein vs 0.68 ng/mg protein, respectively; P < .001). At 90% specificity of the assay (CEA, 2.13 ng/mg protein), the corresponding sensitivity for breast cancer detection was 62%, according to the receiver operating characteristic curve drawn. The APC gene promoter 1A and the promoter region of the cyclin D2 gene were methylated in 42% (14/33) and 70% (23/33) of the breast cancer aspiration fluid samples, respectively. A cumulative incidence of methylation of these 2 genes was 85% (28/33). The APC and cyclin D2 gene promoters were both unmethylated in the aspiration fluids from 19 women with nonmalignant breast disease. CONCLUSIONS Breast aspiration fluid CEA concentration and the methylation of the APC gene promoter 1A and the promoter region of the cyclin D2 gene can be used as tumor markers to overcome some of the limitations of aspiration cytology. In combination with the mammogram and physical examination, assays for these markers could be used to help determine a definitive diagnosis when cytologic results are suspicious for malignancy.


World Journal of Surgical Oncology | 2009

Predictive factors for breast cancer in patients diagnosed atypical ductal hyperplasia at core needle biopsy

Byung Joo Chae; Ahwon Lee; Byung Joo Song; Sang Seol Jung

BackgroundPercutaneous core needle biopsy (CNB) is considered to be the standard technique for histological diagnosis of breast lesions. But, it is less reliable for diagnosing atypical ductal hyperplasia (ADH). The purpose of the present study was to predict, based on clinical and radiological findings, which cases of ADH diagnosed by CNB would be more likely to be associated with a more advanced lesion on subsequent surgical excision.MethodsBetween February 2002 and December 2007, consecutive ultrasound-guided CNBs were performed on suspicious breast lesions at Seoul St. Marys Hospital. A total of 69 CNBs led to a diagnosis of ADH, and 45 patients underwent follow-up surgical excision. We reviewed the medical records and analyses retrospectively.ResultsSixty-nine patients were diagnosed with ADH at CNB. Of these patients, 45 underwent surgical excision and 10 (22.2%) were subsequently diagnosed with a malignancy (ductal carcinoma in situ, n = 8; invasive cancer, n = 2). Univariate analysis revealed age (≥ 50-years) at the time of core needle biopsy (p = 0.006), size (> 10 mm) on imaging (p = 0.033), and combined mass with microcalcification on sonography (p = 0.029) to be associated with underestimation. When those three factors were included in multivariate analysis, only age (p = 0.035, HR 6.201, 95% CI 1.135-33.891) was an independent predictor of malignancy.ConclusionAge (≥ 50) at the time of biopsy is an independent predictive factor for breast cancer at surgical excision in patients with diagnosed ADH at CNB. For patients diagnosed with ADH at CNB, only complete surgical excision is the suitable treatment option, because we could not find any combination of factors that can safely predict the absence of DCIS or invasive cancer in a case of ADH.

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Byung Joo Song

Catholic University of Korea

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Bong Joo Kang

Catholic University of Korea

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Sung Hun Kim

Catholic University of Korea

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Kyo-Young Lee

Catholic University of Korea

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Yeong-Jin Choi

Catholic University of Korea

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Chang Suk Kang

Catholic University of Korea

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Chan Kwon Jung

Catholic University of Korea

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Jong Sup Park

Catholic University of Korea

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Sung Eun Rha

Catholic University of Korea

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Kyo Young Lee

Catholic University of Korea

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