Sumin Ahn

Human epidermal growth factor receptor 2 (HER2) protein overexpression and/or HER2 gene amplification is found in about 20% of invasive breast cancers. It is a sole predictive marker for treatment benefits from HER2 targeted therapy and thus, HER2 testing is a routine practice for newly diagnosed breast cancer in pathology. Currently, HER2 immunohistochemistry (IHC) is used for a screening test, and in situ hybridization is used as a confirmation test for HER2 IHC equivocal cases. Since the Amer

PD-L1 expression is being considered a potential biomarker for response of anti-PD-1 or anti-PD-L1 agents in various tumors. The reported frequency of PD-L1 positivity varies in thyroid carcinomas, and multiple factors may contribute to the variability in PD-L1 positivity. We evaluated the PD-L1 expression in various thyroid cancers on a large scale. A total of 407 primary thyroid cancers with a median 13.7-year of follow-up were included. We evaluated the frequency of PD-L1 expression using a r

Pembrolizumab appears promising for patients with programmed cell death ligand-1 (PD-L1)-positive solid tumors. However, data on immunotherapy for biliary tract cancers (BTC) are limited. We aimed to investigate the predictive value of PD-L1 expression as an immunotherapeutic biomarker in BTC. Patients with advanced BTC (n = 175) were screened for PD-L1 expression using PharmDx assay and microsatellite instability (MSI) status. Of the total of 175 patients, 125 (71%) showed tumoral PD-L1 positiv

NSCLC can acquire a neuroendocrine phenotype with or without EGFR TKI treatment.

BACKGROUND: Thymic neuroendocrine carcinomas (NECs) are uncommon, for which there is no established information available because of a limited number of epidemiological study in Asia. METHODS: We reviewed 21 cases of surgically resected thymic NECs, and evaluated their pathological and clinical features. RESULTS: It showed male predominance (male/female ratio, 15/6) with wide age range from 20 to 72 years (mean age, 49 years). All 21 cases were divided into two types according to the World Healt

OBJECTIVE: The aim of this study was to evaluate the diagnostic accuracy of fine needle aspiration (FNA) cytology of benign salivary gland tumors with myoepithelial cell participation, namely, pleomorphic adenoma, basal cell adenoma and myoepithelioma, at a single institution over a period of 10 years. STUDY DESIGN: This study was based on 575 cytologic and matching histological samples (534 pleomorphic adenomas, 26 basal cell adenomas and 15 myoepitheliomas). RESULTS: In most cases (393/534) of

CONTEXT: - The Ki-67 index is strongly prognostic and is used as a surrogate marker to distinguish luminal A from luminal B breast cancer types. OBJECTIVE: - To investigate differences in Ki-67 index between core needle biopsy samples and matched surgical samples in breast cancer. DESIGN: - We included patients with invasive breast cancer who did not receive neoadjuvant therapy. A total of 89 pairs of core needle biopsies and surgical specimens were collected, and the Ki-67 index was assessed in

High MTDH expression may be a prognostic predictor of shorter DFS in HCC patients after curative hepatectomy.

AIMS: Pembrolizumab has shown promising results for patients with programmed cell death ligand-1 (PD-L1)-positive advanced biliary tract cancer in an ongoing clinical trial. However, data on PD-L1 expression in bile duct cancers is limited, and the frequency of PD-L1 positivity varies, which may be partly due to the assay used. The aim of this study was to evaluate PD-L1 expression status in bile duct cancers by using 22C3, SP263 and E1L3N antibodies. METHODS AND RESULTS: We evaluated PD-L1 expr

Tumor-infiltrating lymphocyte (TIL) levels have prognostic and predictive values in treatment-naïve breast cancers. However, there have been controversies regarding TIL subset changes and their clinical implications in post-treatment breast cancers. This study aimed to explore change and prognostic significance of TIL subset infiltration after primary systemic therapy (PST) in breast cancer. One-hundred-fifty-five patients who had residual disease after anthracycline- or anthracycline plus taxan

PURPOSE: Alteration of biomarker status after primary systemic therapy (PST) is occasionally found in breast cancer. This study was conducted to clarify the clinical implications of change of biomarker status in breast cancer patients treated with PST. MATERIALS AND METHODS: The pre-chemotherapeutic biopsy and post-chemotherapeutic resection specimens of 442 breast cancer patients who had residual disease after PST were included in this study. The association between changes of biomarker status