Se Jin Jang

Activation of the AXL kinase causes resistance to EGFR-targeted therapy in lung cancer

Human non–small cell lung cancers (NSCLCs) with activating mutations in EGFR frequently respond to treatment with EGFR-targeted tyrosine kinase inhibitors (TKIs), such as erlotinib, but responses are not durable, as tumors acquire resistance. Secondary mutations in EGFR (such as T790M) or upregulation of the MET kinase are found in over 50% of resistant tumors. Here, we report increased activation of AXL and evidence for epithelial-to-mesenchymal transition (EMT) in multiple in vitro and in vivo EGFR-mutant lung cancer models with acquired resistance to erlotinib in the absence of the EGFR p.Thr790Met alteration or MET activation. Genetic or pharmacological inhibition of AXL restored sensitivity to erlotinib in these tumor models. Increased expression of AXL and, in some cases, of its ligand GAS6 was found in EGFR-mutant lung cancers obtained from individuals with acquired resistance to TKIs. These data identify AXL as a promising therapeutic target whose inhibition could prevent or overcome acquired resistance to EGFR TKIs in individuals with EGFR-mutant lung cancer.

EMR versus gastrectomy for intramucosal gastric cancer: comparison of long-term outcomes

BACKGROUND Limited data exist regarding the long-term outcomes of EMR compared with gastrectomy. OBJECTIVE To compare the long-term outcomes after EMR and surgery. DESIGN Retrospective analysis with propensity-score matching. SETTING Tertiary care center. PATIENTS This study involved 215 patients with intramucosal gastric cancer completely removed by EMR and 843 patients who underwent curative surgical resection between January 1997 and August 2002. Propensity-score matching yielded 551 matched patients. INTERVENTIONS EMR versus surgery. MAIN OUTCOME MEASUREMENTS Death and recurrence. RESULTS In the matched cohort, there were no significant between-group differences in the risk of death (hazard ratio [HR] for the EMR group 1.39; 95% CI, 0.87-2.23) or recurrence (HR 1.18; 95% CI, 0.22-6.35). Although patients who underwent EMR had higher risk of metachronous gastric cancers (HR 6.72; 95% CI, 2.00-22.58), all recurrent or metachronous gastric cancers after EMR were successfully re-treated without affecting overall survival. Although complication rates were similar (odds ratio 0.84; 95% CI, 0.41-1.70), there were no mortalities in the EMR group compared with 2 in the surgery group. The EMR group had a significantly shorter hospital stay (median 8 days, interquartile range [IQR] 6-11 days vs 15 days, IQR 12-19 days; P<.001) and lower cost of care (

Visceral obesity as a risk factor for colorectal neoplasm

2049, IQR

Unusual Mesenchymal Liver Tumors in Adults: Radiologic-Pathologic Correlation

1586-2425 vs

Unchanging trend of esophagogastric junction adenocarcinoma in Korea: experience at a single institution based on Siewert's classification

4042, IQR

Focal early stage cancer in ampullary adenoma: surgery or endoscopic papillectomy?

3458-4959; P<.001). LIMITATIONS Retrospective, nonrandomized study. CONCLUSIONS EMR was comparable to surgery in terms of risk of death and recurrence. Because of its lower medical costs and shorter duration of hospital stay, EMR has advantages over surgery.

Novel Classification and Pathogenetic Analysis of Hypoganglionosis and Adult-Onset Hirschsprung’s Disease

Background and Aim:  Obesity as a risk factor for colorectal neoplasm (CRN) is controversial. In the present study, we evaluated visceral obesity as a risk factor for CRN.

Clinicopathological review of 61 patients with early bile duct cancer.

OBJECTIVE Our purpose was to review a broad spectrum of mesenchymal liver tumors in adults and present their cross-sectional imaging characteristics including radiologic-pathologic correlation. CONCLUSION Cross-sectional imaging findings of mesenchymal liver tumors in adults are varied and some may overlap with others or even with more common malignant epithelial tumors. However, in some cases, their appearances at cross-sectional imaging studies may reflect characteristic abnormalities that suggest a specific diagnosis. Therefore, familiarity with the radiologic findings of mesenchymal liver tumors and understanding their pathological background is important for increasing the accuracy of radiologic diagnosis.

Diffuse pancreatic ductal adenocarcinoma: Characteristic imaging features

The incidence of adenocarcinoma of the esophagogastric junction (AEG) has been increasing in Western countries. It is unclear, however, whether similar changes are occurring in Asia. We therefore investigated the incidence of AEG in Korea, and assessed the clinical characteristics of three types of AEG based on Siewerts classification. We retrospectively reviewed the medical records of 16 811 patients diagnosed with esophageal squamous cell carcinoma (ESC, n= 1450) or gastric noncardiac adenocarcinoma (GNCA, n= 14 751) between 1992 and 2006. The patients were divided into three 5-year cohorts (cohort A [1992-1996], n= 2734, cohort B [1997-2001], n= 5727, and cohort C [2002-2006], n= 8350), and the ratios of AEG (n= 610) to non-AEG (ESC and GNCA) in each cohort were compared. Using Siewerts classification, the tumors were categorized into one of three types, and patient demographic features and 5-year survival rates were compared. The ratio of AEG to non-AEG cases did not change over time (0.037, 0.034, and 0.039 for cohorts A, B, and C, respectively; P= 0.40). Of the 610 patients with AEG, 23 (3.7%) had type 1 tumors, 47 (7.7%) had type 2, and 540 (88.5%) had type 3. The 5-year survival rate of patients with type 1 AEG was much lower (4.8 +/- 4.7%) than that of those with type 2 (47.9 +/- 7.8%) and type 3 (47.4 +/- 2.5%) tumors. Unlike in Western countries, the ratio of AEG to non-AEG cases has not increased over time in Korea. Type 1 AEG was rarer and associated with a more unfavorable prognosis in Korea than in Western countries.