Journal of Pathology and Translational Medicine

Ja Seung Koo

4 Articles

Galectin-3 Expression and BRAF Mutation in Cases of Cytologically Suspicious Papillary Thyroid Carcinoma.: Dokyung Kim, Hyunki Kim, Jinyoung Kwak, Minju Kim, Hyung Jae Jung, Ja Seung Koo, Beom Jin Lim, Chankwon Jung, SoonWon Hong; Korean J Pathol. 2010;44(2):191-198.; DOI: https://doi.org/10.4132/KoreanJPathol.2010.44.2.191

Abstract PDF: BACKGROUND
Fine needle aspiration, which is known as the most accurate and cost-effective method for diagnosis of thyroid nodule, still may result in indeterminate cases that are pauci-cellular and show minor nuclear atypia, but most cases are associated with suspicion of papillary thyroid carcinoma (PTC). A B-type Raf kinase (BRAF) mutation was found in about half of PTCs and galectin-3 was expressed by malignant tumors, helping us to differentiate malignancies from benign lesions.
METHODS
Cases studied included histologically 44 confirmed PTC cases and 18 benign cases previously diagnosed as suspicious of PTC using cytologic examination. Cases were analyzed for galectin-3 expression by immunohistochemical staining and BRAF mutation by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) with a new restriction enzyme.
RESULTS
All 44 cases of PTC and 8 of 18 benign controls expressed galectin-3. BRAF mutations were found in only 9 of the 44 PTC cases. Assessment of galectin-3 expression demonstrated high sensitivity but low specificity. Evaluation of BRAF mutation revealed high specificity and low sensitivity.
CONCLUSIONS
This study suggests that the combined application of these two methods for PTC of suspicious cytology is complementary.

Cytologic Features of Diffuse Sclerosing Variant of Papillary Carcinoma: Cytohistopathologic Analysis of 16 Cases.: Ja Seung Koo, Woohee Jung, Soonwon Hong, Hyunee Yim; Korean J Pathol. 2009;43(6):557-561.; DOI: https://doi.org/10.4132/KoreanJPathol.2009.43.6.557

Abstract PDF: BACKGROUND
The exact preoperative diagnosis of diffuse sclerosing papillary carcinoma (DSPC) is required for aggressive surgical treatment due to its extended involvement with thyroid and neck lymph nodes. The present study investigated the cytomorphologic characteristics of DSPC and identified cytologic features for preoperative diagnosis of DSPC. METHODS: A retrospective review of cytologic and histologic features of 16 patients diagnosed with DSPC after thyroidectomy and underwent preoperative fine needle aspiration cytology (FNAC) was performed.
RESULTS
Prominent psammoma bodies were observed in 16 (100%) and 10 (62.5%) cases of histology and FNAC, respectively. Lymphocytes were observed in nine (56.2%) and four (25.0%) cases, and squamous cells were noted in seven cases (43.7%) and one case (6.2%) on histology and FNAC, respectively. Nuclear grooves and inclusions, which are characteristics of papillary carcinoma, were observed in FNAC and histology slides in all 16 cases. CONCLUSIONS: DSPC displays prominent psammoma bodies and characteristic nuclear features of papillary carcinoma such as nuclear groove and inclusion in FNAC. However, the preoperative diagnosis of DSPC using only FNAC could be difficult due to the absence of other characteristic features such as lymphocytes and metaplastic squamous cells.

An Unusual Type of Acute Renal Failure due to Extensive Crystal Deposition in the Renal Tubular Epithelium and Interstitium: A Case Report.: Ja Seung Koo, Eunah Shin, Shin Woo Kang, Hyeon Joo Jeong; Korean J Pathol. 2004;38(5):337-340.

Abstract PDF: Acute tubular necrosis is a major cause of acute renal failure. Acute renal failure that is caused by crystal deposition can result from drug toxicity, lymphoplasmacytic neoplasms, ingestion of industrial organic solvents, or intratubular obstruction due to degenerated red blood cells and red blood cell casts. We herein present an uncommon case of acute renal failure in a 57-year-old woman showing an unusually massive accumulation of variable-sized, round, ellipsoid or rhomboid, pale-pink, refractile bodies in the proximal and distal tubular epithelial cells, interstitial macrophages and Bowman's spaces. These bodies were electron dense with a maximum diameter of 3 micrometer. The information we gathered from the patient history, the laboratory data and the various histochemical and immunohistochemical analyses failed to reveal the exact nature of these crystal-like structures.

Pseudofungi Associated with a Granulomatous Response in a Lymph Node: A Case Report.: Haeryoung Kim, Ja Seung Koo, Hyosup Shim, Gijong Yi, Sang Ho Cho; Korean J Pathol. 2004;38(1):64-67.

Abstract PDF: . We present herein a case of pseudofungi incidentally found in the mediastinal lymph nodes of a 31-year-old woman who had a left pneumonectomy for a pulmonary blastoma. The pseudofungi were located in the subcapsular sinuses of the lymph nodes with an associated granulomatous reaction. They revealed yellowish-brown hyphae-like structures with pseudosepta and irregular branching at various angles intermingled with round yeast-like forms. These structures stained positively with periodic acid-Schiff and Gomori methenamine silver, but also stained strongly positive for Prussian blue suggesting that they contain iron. The characteristic morphological features of pseudofungi are discussed with emphasis on the features that distinguish them from true fungal organisms.

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