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Featured researches published by Bhumsuk Keam.


The New England Journal of Medicine | 2015

Cabozantinib versus Everolimus in Advanced Renal-Cell Carcinoma

Toni K. Choueiri; Bernard Escudier; Thomas Powles; Paul N. Mainwaring; Brian I. Rini; Frede Donskov; Hans J. Hammers; Thomas E. Hutson; Jae Lyun Lee; Katriina Peltola; Bruce J. Roth; Georg A. Bjarnason; Lajos Géczi; Bhumsuk Keam; Pablo Maroto; Daniel Y.C. Heng; Manuela Schmidinger; Philip W. Kantoff; Anne E. Borgman-Hagey; Colin Hessel; Christian Scheffold; Gisela Schwab; Nizar M. Tannir; Robert J. Motzer

BACKGROUND Cabozantinib is an oral, small-molecule tyrosine kinase inhibitor that targets vascular endothelial growth factor receptor (VEGFR) as well as MET and AXL, each of which has been implicated in the pathobiology of metastatic renal-cell carcinoma or in the development of resistance to antiangiogenic drugs. This randomized, open-label, phase 3 trial evaluated the efficacy of cabozantinib, as compared with everolimus, in patients with renal-cell carcinoma that had progressed after VEGFR-targeted therapy. METHODS We randomly assigned 658 patients to receive cabozantinib at a dose of 60 mg daily or everolimus at a dose of 10 mg daily. The primary end point was progression-free survival. Secondary efficacy end points were overall survival and objective response rate. RESULTS Median progression-free survival was 7.4 months with cabozantinib and 3.8 months with everolimus. The rate of progression or death was 42% lower with cabozantinib than with everolimus (hazard ratio, 0.58; 95% confidence interval [CI] 0.45 to 0.75; P<0.001). The objective response rate was 21% with cabozantinib and 5% with everolimus (P<0.001). A planned interim analysis showed that overall survival was longer with cabozantinib than with everolimus (hazard ratio for death, 0.67; 95% CI, 0.51 to 0.89; P=0.005) but did not cross the significance boundary for the interim analysis. Adverse events were managed with dose reductions; doses were reduced in 60% of the patients who received cabozantinib and in 25% of those who received everolimus. Discontinuation of study treatment owing to adverse events occurred in 9% of the patients who received cabozantinib and in 10% of those who received everolimus. CONCLUSIONS Progression-free survival was longer with cabozantinib than with everolimus among patients with renal-cell carcinoma that had progressed after VEGFR-targeted therapy. (Funded by Exelixis; METEOR ClinicalTrials.gov number, NCT01865747.).


Journal of Clinical Oncology | 2016

Antitumor Activity of Pembrolizumab in Biomarker-Unselected Patients With Recurrent and/or Metastatic Head and Neck Squamous Cell Carcinoma: Results From the Phase Ib KEYNOTE-012 Expansion Cohort

Laura Q. Chow; Robert I. Haddad; Shilpa Gupta; Amit Mahipal; Ranee Mehra; Makoto Tahara; Raanan Berger; Joseph Paul Eder; Barbara Burtness; Se-Hoon Lee; Bhumsuk Keam; Hyunseok Kang; Kei Muro; Jared Weiss; Ravit Geva; Chia Chi Lin; Hyun Cheol Chung; Amy Meister; Marisa Dolled-Filhart; Kumudu Pathiraja; Jonathan D. Cheng; Tanguy Y. Seiwert

Purpose Treatment with pembrolizumab, an anti–programmed death-1 antibody, at 10 mg/kg administered once every 2 weeks, displayed durable antitumor activity in programmed death-ligand 1 (PD-L1) –positive recurrent and/or metastatic (R/M) head and neck squamous cell carcinoma (HNSCC) in the KEYNOTE-012 trial. Results from the expansion cohort, in which patients with HNSCC, irrespective of biomarker status, received a fixed dose of pembrolizumab at a less frequent dosing schedule, are reported. Patients and Methods Patients with R/M HNSCC, irrespective of PD-L1 or human papillomavirus status, received pembrolizumab 200 mg intravenously once every 3 weeks. Imaging was performed every 8 weeks. Primary end points were overall response rate (ORR) per central imaging vendor (Response Evaluation Criteria in Solid Tumors v1.1) and safety. Secondary end points included progression-free survival, overall survival, and association of response and PD-L1 expression. Patients who received one or more doses of pembrolizumab were included in analyses. Results Of 132 patients enrolled, median age was 60 years (range, 25 to 84 years), 83% were male, and 57% received two or more lines of therapy for R/M disease. ORR was 18% (95% CI, 12 to 26) by central imaging vendor and 20% (95% CI, 13 to 28) by investigator review. Median duration of response was not reached (range, ≥ 2 to ≥ 11 months). Six-month progression-free survival and overall survival rates were 23% and 59%, respectively. By using tumor and immune cells, a statistically significant increase in ORR was observed for PD-L1–positive versus –negative patients (22% v 4%; P = .021). Treatment-related adverse events of any grade and grade ≥ 3 events occurred in 62% and 9% of patients, respectively. Conclusion Fixed-dose pembrolizumab 200 mg administered once every 3 weeks was well tolerated and yielded a clinically meaningful ORR with evidence of durable responses, which supports further development of this regimen in patients with advanced HNSCC.


Breast Cancer Research | 2011

Ki-67 can be used for further classification of triple negative breast cancer into two subtypes with different response and prognosis

Bhumsuk Keam; Seock-Ah Im; Kyung-Hun Lee; Sae-Won Han; Do-Youn Oh; Jee Hyun Kim; Se-Hoon Lee; Wonshik Han; Dong-Wan Kim; Tae-You Kim; In Ae Park; Dong-Young Noh; Dae Seog Heo; Yung-Jue Bang

IntroductionTriple negative breast cancer (TNBC) has a poorer survival, despite a higher response rate to neoadjuvant chemotherapy. The purpose of this study was to identify the predictive or prognostic value of Ki-67 among patients with TNBC treated with neoadjuvant chemotherapy, and the role of Ki-67 in further classification of TNBC.MethodsA total of 105 TNBC patients who received neoadjuvant docetaxel/doxorubicin chemotherapy were included in the present study. Pathologic complete response (pCR) rate, relapse-free survival (RFS), and overall survival (OS) were compared according to the level of Ki-67.ResultspCR was observed in 13.3% of patients. TNBC with high Ki-67 expression (≥10%) showed a higher pCR rate to neoadjuvant chemotherapy than TNBC with low Ki-67 expression. None of the low Ki-67 group achieved pCR (18.2% in the high Ki-67 group vs. 0.0% in the low Ki-67 group, P = 0.019). However, a high Ki-67 expression was significantly associated with poor RFS and OS in TNBC, despite a higher pCR rate (P = 0.005, P = 0.019, respectively). In multivariate analysis, high Ki-67 was an independent prognostic factor for RFS in TNBC (hazard ratio = 7.82, P = 0.002). The high Ki-67 group showed a similar pattern of recurrence with overall TNBC, whereas the low Ki-67 group demonstrated a relatively constant hazard rate for relapse.ConclusionsTNBC with high Ki-67 was associated with a more aggressive clinical feature despite a higher pCR rate. High proliferation index Ki-67 can be used for further classification of TNBC into two subtypes with different responses and prognosis.


BMC Cancer | 2007

Prognostic impact of clinicopathologic parameters in stage II/III breast cancer treated with neoadjuvant docetaxel and doxorubicin chemotherapy: paradoxical features of the triple negative breast cancer

Bhumsuk Keam; Seock-Ah Im; Hee-Jun Kim; Do-Youn Oh; Jee Hyun Kim; Se-Hoon Lee; Eui Kyu Chie; Wonshik Han; Dong-Wan Kim; Woo Kyung Moon; Tae-You Kim; In Ae Park; Dong Young Noh; Dae Seog Heo; Sung Whan Ha; Yung-Jue Bang

BackgroundPrognostic factors in locally advanced breast cancer treated with neoadjuvant chemotherapy differ from those of early breast cancer. The purpose of this study was to identify the clinical significance of potential predictive and prognostic factors in breast cancer patients treated by neoadjuvant chemotherapy.MethodsA total of 145 stage II and III breast cancer patients received neoadjuvant docetaxel/doxorubicin chemotherapy were enrolled in this study. We examined the clinical and biological factors (ER, PR, p53, c-erbB2, bcl-2, and Ki-67) by immunohistochemistry. We analyzed clinical outcome and their correlation with clinicopathologic parameters.ResultsAmong the clinicopathologic parameters investigated, none of the marker was correlated with response rate (RR) except triple negative phenotype. Patients with triple negative phenotype showed higher RR (83.0% in triple negative vs. 62.2% in non-triple negative, p = 0.012) and pathologic complete RR (17.0% in triple negative vs. 3.1% in non-triple negative, p = 0.005). However, relapse free survival (RFS) and overall survival (OS) were significantly shorter in triple negative breast cancer patients (p < 0.001, p = 0.021, respectively). Low histologic grade, positive hormone receptors, positive bcl-2 and low level of Ki-67 were associated with prolonged RFS. In addition, positive ER and positive bcl-2 were associated with prolonged OS. In our homogeneous patient population, initial clinical stage reflects RFS and OS more precisely than pathologic stage. In multivariate analysis, initial clinical stage was the only significant independent prognostic factor to impact on OS (hazard ratio 3.597, p = 0.044).ConclusionSeveral molecular markers provided useful predictive and prognostic information in stage II and III breast cancer patients treated with neoadjuvant docetaxel/doxorubicin chemotherapy. Triple negative phenotype was associated with shorter survival, even though it was associated with a higher response rate to neoadjuvant chemotherapy.


Journal of Thoracic Oncology | 2013

Heterogeneity of Genetic Changes Associated with Acquired Crizotinib Resistance in ALK-Rearranged Lung Cancer

Soyeon Kim; Tae Min Kim; Dong-Wan Kim; Heounjeong Go; Bhumsuk Keam; Se-Hoon Lee; Ja-Lok Ku; Doo Hyun Chung; Dae Seog Heo

Background: Anaplastic lymphoma kinase (ALK)-rearranged non–small-cell lung cancer (NSCLC) is markedly sensitive to the ALK inhibitor crizotinib. However, acquired resistance to crizotinib is inevitable through several mechanisms. Therefore, this study was conducted to identify genetic alterations associated with crizotinib resistance. Methods: Tumor samples were derived from seven ALK-positive NSCLC patients who showed acquired resistance to crizotinib, and these patients were analyzed for ALK, EGFR, and KRAS mutations and ALK and EGFR gene amplifications. In vitro cytotoxicity of crizotinib and ALK downstream signals were compared between crizotinib-naive and -resistant NSCLC cells. Results: After a median duration of 6 months (range, 4–12 months), seven ALK-positive NSCLC patients developed acquired resistance to crizotinib. Three patients harbored secondary ALK mutations, including one patient with both mutations: L1196M (n = 2) and G1269A (n = 2). Of note, one patient displayed ALK gene copy number gain (4.1-fold increase compared with the pre-crizotinib specimen) and EGFR L858R mutation with high polysomy. The amphiregulin concentration was high in the supernatant fluid from five patients with malignant pleural effusion (116.4–18934.0 pg/ml). SNU-2535 cells derived from a patient who harbored the G1269 mutation were resistant to crizotinib treatment similar to H3122 CR1 cells. L1196M and G1269A mutant clones were less sensitive to crizotinib and ALK downstream signals were ineffectively suppressed in these clones. Conclusions: Genetic changes associated with crizotinib resistance are heterogeneous in ALK-rearranged NSCLC patients who respond to crizotinib and subsequently develop resistance.


JAMA | 2014

Epidermal growth factor receptor tyrosine kinase inhibitors vs conventional chemotherapy in non-small cell lung cancer harboring wild-type epidermal growth factor receptor: a meta- analysis

June Koo Lee; Seokyung Hahn; Dong-Wan Kim; Koung Jin Suh; Bhumsuk Keam; Tae Min Kim; Se-Hoon Lee; Dae Seog Heo

IMPORTANCE Current guidelines recommend both epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) and cytotoxic chemotherapy drugs as standard treatment options for patients with wild-type (WT) EGFR who were previously treated for non-small cell lung cancer (NSCLC). However, it is not clear that EGFR TKIs are as efficacious as chemotherapy in patients with WT EGFR. OBJECTIVE To determine the association between first-generation EGFR TKI vs chemotherapy and survival in advanced NSCLC patients with WT EGFR. DATA SOURCES PubMed, EMBASE, Cochrane database, and meeting abstracts of the American Society of Clinical Oncology and European Society of Medical Oncology through December 2013. STUDY SELECTION Eligible studies were randomized controlled trials comparing EGFR TKI with conventional chemotherapy in patients with advanced NSCLC. Out of 1947 retrieved articles, 11 trials incorporating 1605 patients with WT EGFR were included. DATA EXTRACTION AND SYNTHESIS Two reviewers extracted trial characteristics and outcomes. The risk of bias was evaluated using the Cochrane tool. All measures were pooled using random-effects models and 95% CIs were calculated. MAIN OUTCOMES AND MEASURES The primary outcome was progression-free survival (PFS), measured as hazard ratios (HRs). The secondary outcomes were objective response rate and overall survival, expressed as relative risks and HRs, respectively. RESULTS Among patients with WT EGFR tumors, chemotherapy was associated with improvement of PFS, compared with TKI (HR for TKI, 1.41; 95% CI, 1.10-1.81). No statistically significant subgroup difference was identified in terms of line of treatment (first-line vs second- or later-line), experimental drug, dominant ethnicity, or EGFR mutation analysis method. Trials using more sensitive platforms than direct sequencing were associated with a significant PFS benefit with chemotherapy (HR for TKI, 1.84; 95% CI, 1.35-2.52). The association of chemotherapy with improvement in PFS was also significant in second- or later-line trials (HR, 1.34; 95% CI, 1.09-1.65). The objective response rate was higher with chemotherapy (92/549, 16.8%, vs 39/540, 7.2%, for TKI; relative risk for TKI, 1.11; 95% CI, 1.02-1.21); however, no statistically significant difference was observed with respect to overall survival (HR for TKI, 1.08; 95% CI, 0.96-1.22). CONCLUSIONS AND RELEVANCE Among patients with advanced NSCLC harboring WT EGFR, conventional chemotherapy, compared with first-generation EGFR TKI, was associated with improvement in PFS but not overall survival.


Japanese Journal of Clinical Oncology | 2008

Aggressiveness of Cancer-Care near the End-of-Life in Korea

Bhumsuk Keam; Do-Youn Oh; Se-Hoon Lee; Dong-Wan Kim; Mi Ra Kim; Seock-Ah Im; Tae-You Kim; Yung-Jue Bang; Dae Seog Heo

OBJECTIVE The aim of this study was to examine the appropriateness of chemotherapy and care in Korean cancer patients near the end-of-life. METHODS We designed a retrospective cohort composed of patients diagnosed as having metastatic cancer and who received palliative chemotherapy at Seoul National University Hospital in 2002. Two hundred and ninety-eight patients who died of cancer were evaluated in terms of the appropriateness of the cancer-care they received, including chemotherapy. RESULTS Median duration of chemotherapy was 6.02 months compared with 8.67 months for median overall survival. The median period between last chemotherapy and death was 2.02 months. Of the 298 patients, 50.3% received chemotherapy during the last 2 months of life. Furthermore, 17 patients (5.7%) died within 2 weeks after receiving chemotherapy. The proportion who visited an emergency room (ER) more than once during the last months of life was 33.6%, and the average number of ER visits after a diagnosis of cancer was 1.72. Only 9.1% of patients were referred to a hospice consultation service and only 11.7% of patients agreed with written DNR. CONCLUSIONS Among patients who died of cancer, significant proportions were found to have received chemotherapy up to the end-of-life and to have visited ERs. Hospice referrals and discussions about DNR were not conducted well during the end-of-life period in Korea.


Cancer | 2013

Total lesion glycolysis in positron emission tomography is a better predictor of outcome than the International Prognostic Index for patients with diffuse large B cell lymphoma

Tae Min Kim; Jin Chul Paeng; In Kook Chun; Bhumsuk Keam; Yoon Kyung Jeon; Se-Hoon Lee; Dong-Wan Kim; Dong Soo Lee; Chul-Woo Kim; June-Key Chung; Il Han Kim; Dae Seog Heo

This study was undertaken to evaluate the prognostic value of quantitative metabolic parameters in [18F]2‐fluoro‐2‐deoxyglucose (FDG)‐positron emission tomography (PET) for diffuse large B cell lymphoma (DLBCL).


Journal of Thoracic Oncology | 2013

Erlotinib Versus Gefitinib for Control of Leptomeningeal Carcinomatosis in Non–Small-Cell Lung Cancer

Eun Young Lee; Bhumsuk Keam; Dong-Wan Kim; Tae Min Kim; Se-Hoon Lee; Doo Hyun Chung; Dae Seog Heo

Introduction: Leptomeningeal carcinomatosis (LMC) from non–small-cell lung cancer (NSCLC) is a clinically important neurological complication in the era of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs). The purpose of this study was to compare the efficacy of gefitinib and erlotinib for control of LMC in NSCLC. Methods: We retrospectively reviewed medical records of 25 EGFR TKI–treated NSCLC patients with LMC between 2004 and 2012 at Seoul National University Hospital. Cytologic negative conversion was defined as absence of malignant cells in the cerebrospinal fluid three times in succession. Cytologic conversion rates were compared between the gefitinib arm and the erlotinib arm. Results: Nine patients had exon 21 point mutations and eight patients had exon 19 deletional mutations. Nine of 25 patients had already used EGFR TKIs and switched to another EGFR TKI after LMC occurrence. The other 16 patients received EGFR TKIs after LMC diagnoses. All the patients received intrathecal chemotherapy, including methotrexate, and six of them were treated with combined whole-brain radiotherapy. Gefitinib and erlotinib were administered to 11 and 14 patients, respectively. Ten patients had LMC controlled with cytologic negative conversion, whereas in 15 patients, cytological clearance of the cerebrospinal fluid could not be achieved. Patients treated with erlotinib showed better cytologic conversion rate of LMC than those with gefitinib (64.3% [9 of 14] in the erlotinib arm versus 9.1% [1 of 11] in the gefitinib arm; p = 0.012). Conclusion: This study suggested that erlotinib had better control rate for LMC in NSCLC than gefitinib. Further prospective study is warranted.


Journal of Thoracic Oncology | 2015

Mechanisms of Acquired Resistance to AZD9291: A Mutation-Selective, Irreversible EGFR Inhibitor

Tae Min Kim; Ahnah Song; Dong-Wan Kim; Soyeon Kim; Yong-Oon Ahn; Bhumsuk Keam; Yoon Kyung Jeon; Se-Hoon Lee; Doo Hyun Chung; Dae Seog Heo

Introduction: AZD9291, a third-generation and mutation-selective epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), is active against patients with EGFRT790M-mutant non–small-cell lung cancer (NSCLC) who failed prior treatment with EGFR TKIs. However, acquired resistance to AZD9291 is inevitable. In this study, we identified the mechanisms of acquired resistance to AZD9291 in EGFRT790M-mutant NSCLC. Methods: Four NSCLC patients with both an EGFR exon 19 deletion and the EGFRT790M mutation after developing acquired resistance to first-generation EGFR TKIs received AZD9291 at doses of 20 to 80 mg/day in a phase I trial (NCT01802632). Paired tumor samples before and after treatment were obtained to evaluate EGFR modifications, alternative pathway activation, and histologic transformation. Genetic alterations were analyzed using Sanger sequencing, fluorescence in situ hybridization, real-time polymerase chain reaction, and targeted exome sequencing. Results: All four patients achieved a partial response (median duration of response, 9 months [range, 9–11 months]) and subsequently showed resistance to AZD9291. EGFRT790M-mutant clones depopulated AZD9291-resistant tumors to below 1% (baseline, 14%–36%) in three patients with progression: one with the loss of EGFRLREAT747del/T790M-double mutant clones and two accompanied by transformation to small-cell carcinoma and focal fibroblast growth factor receptor 1 (FGFR1) amplification, respectively. EGFRT790M-mutant clones remained and the EGFR ligand was overexpressed in one patient with focal progression to AZD9291. Conclusion: Acquired resistance mechanisms of AZD9291 in patients with EGFRT790M-mutant NSCLC who failed treatment with first-generation EGFR TKIs include the loss of EGFRT790M-mutant clones plus alternative pathway activation or histologic transformation and EGFR ligand–dependent activation.

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Dae Seog Heo

Seoul National University Hospital

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Tae Min Kim

Seoul National University Hospital

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Dong-Wan Kim

Seoul National University Hospital

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Se-Hoon Lee

Samsung Medical Center

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Miso Kim

Seoul National University Hospital

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Yoon Kyung Jeon

Seoul National University Hospital

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Seock-Ah Im

Seoul National University Hospital

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Doo Hyun Chung

Seoul National University

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Do-Youn Oh

Seoul National University

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Tae-You Kim

Seoul National University

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