Jae Yeon Seok

UNLABELLED: Hepatocellular carcinoma (HCC) and cholangiocarcinoma (CC) are the major primary liver cancers in adults. The phenotypic overlap between HCC and CC has been shown to comprise a continuous liver cancer spectrum. As a proof of this concept, a recent study demonstrated a genomic subtype of HCC that expressed CC-like gene expression traits, such as CC-like HCC, which revealed the common genomic trait of stem-cell-like properties and aggressive clinical outcomes. Scirrhous HCC (S-HCC), a

Chondrosarcoma of the head and neck region is a rare disease, representing approximately 0.1% of all head and neck neoplasms. The 5-year survival rate of chondrosarcoma is 70-80%, showing relatively good prognosis; however, it is known to progress slowly and eventually cause multiple metastases. In this study, we reviewed chondrosarcoma cases experienced at Yonsei University Medical College during the last 15 years to investigate its clinical characteristics and treatment outcome. The medical re

BACKGROUND: In patients with biliary atresia (BA), liver fibrosis and cirrhosis commonly occur even after Kasai hepatoportoenterostomy. Although liver biopsy is the gold standard to evaluate liver fibrosis, it is invasive and may result in life-threatening complications. The aspartate aminotransferase-to-platelet ratio index (APRI) is a safe and simple method to assess liver fibrosis in patients with chronic liver diseases. To use APRI as a postoperative follow-up tool, we validated the diagnost

The Prototheca species is achlorophyllic algae and rarely causes human infection. Human protothecosis presents clinically as a cutaneous infection, olecranon bursitis, and disseminated systemic disease. We report a case of human cutaneous protothecosis involving the left wrist. A 68-year-old man presented with an ill-defined erythematous lesion with crust at the dorsal aspect of his left wrist. A punch biopsy was performed to reveal the histologic features of granulomatous inflammation with necr

Insulinoma-associated protein 1 (INSM1) is shown to be an excellent marker for neuroendocrine differentiation. However, the diagnostic utility of INSM1 in medullary thyroid carcinoma (MTC) has not yet been extensively investigated. INSM1 staining was performed on 21 MTCs, 7 MTC mimickers (including 3 papillary carcinomas, 2 poorly differentiated carcinomas, 1 follicular adenoma, and 1 nodular plasma cell hyperplasia), and 3 cases of C-cell hyperplasia. INSM1 staining of these cases was compared

BACKGROUND: Anaplastic thyroid carcinoma (ATC), a highly aggressive malignancy, has no effective treatment to date. Trophoblast cell-surface antigen 2 (TROP-2), a transmembrane glycoprotein, has been suggested to be a promising novel target for sacituzumab govitecan, an antibody-drug conjugate. 5-Hydroxymethylcytosine (5hmC) has a role in tumor suppression and promoting modification. Additionally, isocitrate dehydrogenase 1 (IDH1) mutations are strongly associated with increased overall survival

Microcystic meningioma is an unusual type of meningioma that has been described under various names including humid, myxomatous, vacuolated, or arachnoid trabecular cell meningioma.1 Histologically, microcystic meningiomas are characterized by numerous cystic spaces filled with edematous fluid and intermixed meningothelial cells of stellate or spider shape. Cytological descriptions of microcystic meningioma have been limited.2,3

The sizes of cytoplasm, nucleus, and intranuclear inclusion were larger in LBP than in CP, indicating that CMV-infected cells are easily detectable in LBP. However, the nucleus-to-cytoplasm ratio was larger in CP, suggesting that differentiation from malignancy or regenerative atypia requires caution in CP.

Papillary cystadenoma (PC) is an epithelial tumor believed to be of mesonephric origin[1] that is found rarely in the female genital tract. Since the original report by Gersell and King in 1988[2], only 14 cases have been reported in the English literature[1,3-5]. All of the reported cases occurred in the mesosalpinx or the broad ligament. Most of the tumors (12 out of 14) were associated with von Hippel-Lindau disease (VHL), similar to epididymal tumors[6]. We report a case of PC within the wal

BACKGROUND: Various efforts have been made to improve the diagnostic accuracy of thyroid fine needle aspiration (FNA) cytology. We changed the diagnostic system by reducing the number of pathologists responsible for the thyroid FNA cytology in the routine work, and analyzed the effect on the pathologist's diagnostic performance. METHODS: Since March 1, 2015, 3 pathologists have been responsible for diagnostic thyroid FNA, previously undertaken by 9 equally. We compared the prechange period (thre

BACKGROUND: Lymphoepithelial carcinoma of the salivary gland is a rare undifferentiated or poorly differentiated squamous cell carcinoma associated with abundant inmphocytes. Only a handful of reports descibe the cytologic features of fine needle aspiration in lymphoepithelial carcinoma of the salivary gland and lymph nodes. CASE: A 29-year-old man presented with a painless mass in his right parotid gland. After the surgical specimen was evaluated, the mass was diagnosed as a lymphoepithelial ca