A Case of Desmoplastic Spitz Nevus with Pseudo-Gland Formation / 대한피부과학회지

Desmoplastic Spitz nevus is a rare variant of Spitz nevus characterized by predominantly spindle-shaped or epithelioid nevus cells within the fibrotic stroma that can be confused with fibrous lesions. A 43-year-old woman presented with a 1-cm-sized dome-shaped papule on the dorsum of her left foot. The lesion showed histopathological features of a desmoplastic Spitz nevus with structures that resemble adenoma. Immunohistochemical staining was positive for S-100 protein, Melan-A, and SOX-10. Herein, we report this case because desmoplastic Spitz nevus is rare and can lead to confusion regarding the diagnosis of adnexal neoplasms.

Molecular biomarker testing for non–small cell lung cancer: consensus statement of the Korean Cardiopulmonary Pathology Study Group

Molecular biomarker testing is the standard of care for non–small cell lung cancer (NSCLC) patients. In 2017, the Korean Cardiopulmonary Pathology Study Group and the Korean Molecular Pathology Study Group co-published a molecular testing guideline which contained almost all known genetic changes that aid in treatment decisions or predict prognosis in patients with NSCLC. Since then there have been significant changes in targeted therapies as well as molecular testing including newly approved targeted drugs and liquid biopsy. In order to reflect these changes, the Korean Cardiopulmonary Pathology Study Group developed a consensus statement on molecular biomarker testing. This consensus statement was crafted to provide guidance on what genes should be tested, as well as methodology, samples, patient selection, reporting and quality control.

Molecular biomarker testing for non–small cell lung cancer: consensus statement of the Korean Cardiopulmonary Pathology Study Group

Molecular biomarker testing is the standard of care for non–small cell lung cancer (NSCLC) patients. In 2017, the Korean Cardiopulmonary Pathology Study Group and the Korean Molecular Pathology Study Group co-published a molecular testing guideline which contained almost all known genetic changes that aid in treatment decisions or predict prognosis in patients with NSCLC. Since then there have been significant changes in targeted therapies as well as molecular testing including newly approved targeted drugs and liquid biopsy. In order to reflect these changes, the Korean Cardiopulmonary Pathology Study Group developed a consensus statement on molecular biomarker testing. This consensus statement was crafted to provide guidance on what genes should be tested, as well as methodology, samples, patient selection, reporting and quality control.

Collagenous Fibroma at the Surgical Site after Thyroidectomy for Papillary Thyroid Carcinoma / 대한이비인후과학회지

Collagenous fibroma (CF) is a rare benign tumor that occurs at various anatomical sites including the head and neck. CFs are often omitted from differential diagnosis before surgery. We describe a case of CF in a 54-year-old male who presented with a growing neck mass of 1-year duration at the site of previous right hemithyroidectomy for papillary thyroid carcinoma (PTC). Although radiologic findings demonstrated a benign tumor, surgical excision was carried out per patient’s preference and to rule out recurrent thyroid cancer. The mass was severely adherent to the surrounding muscles, but was resected completely without any injury to the adjacent structures. Histological studies revealed CF. The postoperative course was uneventful without vocal fold paralysis. CFs can be a diagnostic challenge in preoperative evaluation. Conservative excision was sufficient in most cases without recurrence. Clinicians should be aware of CFs in diagnosis, especially in postoperative site.

Current status and future perspectives of liquid biopsy in non-small cell lung cancer

With advances in target therapy, molecular analysis of tumors is routinely required for treatment decisions in patients with advanced non-small cell lung cancer (NSCLC). Liquid biopsy refers to the sampling and analysis of circulating cell-free tumor DNA (ctDNA) in various body fluids, primarily blood. Because the technique is minimally invasive, liquid biopsies are the future in cancer management. Epidermal growth factor receptor (EGFR) ctDNA tests have been performed in routine clinical practice in advanced NSCLC patients to guide tyrosine kinase inhibitor treatment. In the near future, liquid biopsy will be a crucial prognostic, predictive, and diagnostic method in NSCLC. Here we present the current status and future perspectives of liquid biopsy in NSCLC.

Interobserver Reproducibility of PD-L1 Biomarker in Non-small Cell Lung Cancer: A Multi-Institutional Study by 27 Pathologists

BACKGROUND: Assessment of programmed cell death-ligand 1 (PD-L1) immunohistochemical staining is used for treatment decisions in non-small cell lung cancer (NSCLC) regarding use of PD-L1/programmed cell death protein 1 (PD-1) immunotherapy. The reliability of the PD-L1 22C3 pharmDx assay is critical in guiding clinical practice. The Cardiopulmonary Pathology Study Group of the Korean Society of Pathologists investigated the interobserver reproducibility of PD-L1 staining with 22C3 pharmDx in NSCLC samples.METHODS: Twenty-seven pathologists individually assessed the tumor proportion score (TPS) for 107 NSCLC samples. Each case was divided into three levels based on TPS: <1%, 1%–49%, and ≥50%.RESULTS: The intraclass correlation coefficient for TPS was 0.902±0.058. Weighted κ coefficient for 3-step assessment was 0.748±0.093. The κ coefficients for 1% and 50% cut-offs were 0.633 and 0.834, respectively. There was a significant association between interobserver reproducibility and experience (formal PD-L1 training, more experience for PD-L1 assessment, and longer practice duration on surgical pathology), histologic subtype, and specimen type.CONCLUSIONS: Our results indicate that PD-L1 immunohistochemical staining provides a reproducible basis for decisions on anti–PD-1 therapy in NSCLC.

Atypical Teratoid/Rhabdoid Tumor of Lumbar Spine in an Infant: A Case Report

Atypical teratoid/rhabdoid tumor (AT/RT) of spine usually reported to develop in the brain, while it rarely manifest in the spine. It consists of rhabdoid cells and is highly malignant. AT/RT appears at various sites throughout the body, such as in the central nervous system, liver, kidneys, abdomen, and soft tissues. Among them, spinal AT/RT is rare, and AT/RT of lumbar spine is extremely rare; only a few cases have been reported. We present the case of an AT/RT of lumbar spine in a 16-month-old boy.

Mesothelin Expression in Gastric Adenocarcinoma and Its Relation to Clinical Outcomes

BACKGROUND: Although surgical resection with chemotherapy is considered effective for patients with advanced gastric cancer, it remains the third leading cause of cancer-related death in South Korea. Several studies have reported that mesothelial markers including mesothelin, calretinin, and Wilms tumor protein 1 (WT1) were positive in variable carcinomas, associated with prognosis, and were evaluated as potential markers for targeted therapy. The aim of this study was to assess the immunohistochemical expression of mesothelial markers (mesothelin, calretinin, and WT1) in gastric adenocarcinoma and their relations to clinocopathological features and prognosis. METHODS: We evaluated calretinin, WT1, and mesothelin expression by immunohistochemical staining in 117 gastric adenocarcinomas. RESULTS: Mesothelin was positively stained in 30 cases (25.6%). Mesothelin expression was related to increased depth of invasion (p = .002), lymph node metastasis (p = .013), and presence of lymphovascular (p = .015) and perineural invasion (p = .004). Patients with mesothelin expression had significantly worse disease-free survival rate compared with that of nonmesothelin expression group (p = .024). Univariate analysis showed that mesothelin expression is related to short-term survival. None of the 117 gastric adenocarcinomas stained for calretinin or WT1. CONCLUSIONS: Mesothelin expression was associated with poor prognosis. Our results suggest that mesothelin-targeted therapy should be considered as an important therapeutic alternative for gastric adenocarcinoma patients with mesothelin expression.

Thyroid Fine-Needle Aspiration Cytology Practice in Korea

We reviewed the current status of thyroid fine-needle aspiration cytology (FNAC) in Korea. Thyroid aspiration biopsy was first introduced in Korea in 1977. Currently, radiologists aspirate the thyroid nodule under the guidance of ultrasonography, and cytologic interpretation is only legally approved when a cytopathologist makes the diagnosis. In 2008, eight thyroid-related societies came together to form the Korean Thyroid Association. The Korean Society for Cytopathology and the endocrine pathology study group of the Korean Society for Pathologists have been updating the cytologic diagnostic guidelines. The Bethesda System for Reporting Thyroid Cytopathology was first introduced in 2009, and has been used by up to 94% of institutions by 2016. The average diagnosis rates are as follows for each category: I (12.4%), II (57.9%), III (10.4%), IV (2.9%), V (3.7%), and VI (12.7%). The malignancy rates in surgical cases are as follows for each category: I (28.7%), II (27.8%), III (50.6%), IV (52.3%), V (90.7%), and VI (100.0%). Liquid-based cytology has been used since 2010, and it was utilized by 68% of institutions in 2016. The categorization of thyroid lesions into “atypia of undetermined significance” or “follicular lesion of undetermined significance” is necessary to draw consensus in our society. Immunocytochemistry for galectin-3 and BRAF is used. Additionally, a molecular test for BRAF in thyroid FNACs is actively used. Core biopsies were performed in only 44% of institutions. Even the institutions that perform core biopsies only perform them for less than 3% of all FNACs. However, only 5% of institutions performed core biopsies up to three times more than FNAC.

Molecular Testing of Lung Cancers

Targeted therapies guided by molecular diagnostics have become a standard treatment of lung cancer. Epidermal growth factor receptor (EGFR) mutations and anaplastic lymphoma kinase (ALK) rearrangements are currently used as the best predictive biomarkers for EGFR tyrosine kinase inhibitors and ALK inhibitors, respectively. Besides EGFR and ALK, the list of druggable genetic alterations has been growing, including ROS1 rearrangements, RET rearrangements, and MET alterations. In this situation, pathologists should carefully manage clinical samples for molecular testing and should do their best to quickly and accurately identify patients who will benefit from precision therapeutics. Here, we grouped molecular biomarkers of lung cancers into three categories—mutations, gene rearrangements, and amplifications—and propose expanded guidelines on molecular testing of lung cancers.

Malakoplakia Affecting the Umbilical Cord

No abstract available.

Intraosseous Calcaneal Lipoma with Subtalar Perforation through Cystic Degeneration: A Case Report / 대한족부족관절학회지

Intraosseous lipoma is a benign tumor that originates from proliferating mature lipocytes. It often occurs in the metaphysis of long bones of the lower extremity, and also in the calcaneus, humerus, mandible, sacrum, and rib bones. Frequently, it involutes spontaneously through a process of infarction, calcification, and cyst formation. It can either present as pain, or be asymptomatic and only discovered through an incidental radiological finding. In our case, the patient presented with heel pain. Intraoperatively, it was found that the intraosseous cavity was filled with fat along with an adjacent but separate area of cystic degeneration. There was also a cortical perforation at the cystic lesion which was communicating with the subtalar joint. This cortical breach is most likely the cause of diffuse lateral heel pain experienced by our patient, and such a pathological fracture due to intraosseous lipoma has never been reported.

A Case of Metastatic Low-Grade Endometrial Stromal Sarcoma Treated with Letrozole after Ovarian Ablation by Radiotherapy / Journal of the Korean Cancer Association, 대한암학회지

A 50-year-old woman was admitted to our hospital due to multiple lung nodules detected incidentally on a chest X-ray. A video-assisted thoracoscopic lung biopsy revealed low-grade endometrial stromal sarcoma (LG-ESS). She had undergone a simple hysterectomy 1 year earlier owing to a diagnosis of adenomyosis. A review of her previous hysterectomy specimen showed not endometriosis but LG-ESS. According to the patient's levels of serum follicle stimulating hormone and estradiol, she was in the premenopausal state with retained and normally functioning ovaries. She then underwent ovarian ablation by radiotherapy, after which she was administered 2.5 mg of letrozole once per day. Three months later, the size of the metastatic nodules in both lungs had decreased. The patient was followed up for 24 months while continuing on letrozole, and maintained a partial remission. We report herein on a case of metastatic LG-ESS treated with letrozole after ovarian ablation by radiotherapy.

Extramedullary Solitary Plasmacytoma of the Lymph Nodes / 대한내과학회지

Extramedullary plasmacytomas are uncommon malignant neoplasms that can occur in any organ. They arise most frequently from the upper aerodigestive tract. Lymph nodes are exceedingly rare sites of extramedullary plasmacytomas. Most extramedullary plasmacytomas of the lymph node arise in the cervical lymph nodes. Here, we report a case of an extramedullary plasmacytoma of the lymph node arising from a cervical lymph node. A 43-year-old male patient was admitted to our hospital and presented with a non-tender mass on the left side of his neck, which had been growing slowly for 1 month. The mass was excised. The pathology showed diffuse infiltration of immature plasma cells that were encapsulated by a layer of lymphoid cells, indicating an extramedullary plasmacytoma. He was treated with local radiation of the left cervical area. As of March 2009, he is doing well and shows no further evidence of the disease.

Guideline Recommendations for EGFR Mutation Testing in Lung Cancer: Proposal of the Korean Cardiopulmonary Pathology Study Group

Mutations of the epidermal growth factor receptor (EGFR) are the strongest predictive factor for response to EGFR tyrosine kinase inhibitors (TKIs), such as gefitinib and erlotinib. EGFR TKIs are approved in Korea as a first-line treatment for lung cancer patients with mutated EGFR. Rapid and accurate EGFR mutation testing is essential for patient selection and establishing targeted therapies with EGFR TKIs. Thus, a standard set of guideline recommendations for EGFR mutation testing suitable for the Korean medical community is necessary. In this article, we propose a set of guideline recommendations for EGFR mutation testing that was discussed and approved by the Cardiopulmonary Pathology Study Group of the Korean Society of Pathologists.

Cytologic Findings of Thyroid Carcinoma Showing Thymus-like Differentiation: A Case Report

Carcinoma showing thymus-like differentiation (CASTLE) is a rare carcinoma of the thyroid or adjacent soft tissue of the neck with a histologic resemblance to thymic epithelial tumors. Although the fine-needle aspiration (FNA) plays a central role in the initial evaluation of thyroid nodules, few reports about the cytologic findings of CASTLE have been found according to a review of literatures. We report cytologic findings of a case of CASTLE. A 34-year-old woman presented with a 2-month history of sore throat. The FNA showed that the smear was composed of three dimensional clusters and sheets. The tumor cells were round to ovoid with high nuclear : cytoplasmic ratios. The nuclei were vesicular with small nucleoli. There were some tumor cells showing keratinization. Some lymphocytes were found on the background and within clusters. The presence of poorly-differentiated tumor cells with a focal keratinization and a lymphocytic background on the FNA is suggestive of CASTLE.

Cytologic Findings of Thyroid Carcinoma Showing Thymus-like Differentiation: A Case Report

Carcinoma showing thymus-like differentiation (CASTLE) is a rare carcinoma of the thyroid or adjacent soft tissue of the neck with a histologic resemblance to thymic epithelial tumors. Although the fine-needle aspiration (FNA) plays a central role in the initial evaluation of thyroid nodules, few reports about the cytologic findings of CASTLE have been found according to a review of literatures. We report cytologic findings of a case of CASTLE. A 34-year-old woman presented with a 2-month history of sore throat. The FNA showed that the smear was composed of three dimensional clusters and sheets. The tumor cells were round to ovoid with high nuclear : cytoplasmic ratios. The nuclei were vesicular with small nucleoli. There were some tumor cells showing keratinization. Some lymphocytes were found on the background and within clusters. The presence of poorly-differentiated tumor cells with a focal keratinization and a lymphocytic background on the FNA is suggestive of CASTLE.

A Case of Pheochromocytoma Crisis with Acute Myocardial Infarction Induced by Glucocorticoids Administration

The most common symptoms of pheochromocytoma are paroxysmal or sustained hypertension, or symptoms of paroxysmal adrenergic stimulation such as palpitation, headache, and diaphoresis. These patients can on rare occasion reveal or be complicated with cardiovascular symptoms such as arrhythmia, cardiomyopathy, acute coronary syndrome and cardiogenic shock. These cardiac manifestations of pheochromocytoma may delay the diagnosis, which can cause a catastrophic outcome. A pheochromocytoma crisis is provoked by surgery, anesthesia, exercise and, several drugs and it is known to be an endocrine emergency with mortality as high as 85%. Many classes of drugs are well known to precipitate adverse reactions, but the presentation of pheochromocytoma after the administration of steroid has rarely been reported. We report here on a case of pheochromocytoma crisis with acute myocardial infarction after the patient took prednisolone. Furthermore, we discuss the mechanism of glucocorticoid induced crisis and myocardial infarction in pheochromocytoma patients.

A Case of Endocrine Mucin-Producing Sweat Gland Carcinoma Co-existing with Mucinous Carcinoma: A Case Report

An endocrine mucin-producing sweat gland carcinoma (EMPSGC) is a rare skin tumor that most commonly occurs on the eyelids of elderly women. This tumor is morphologically analogous to endocrine ductal carcinoma in situ and solid papillary carcinoma of the breast. We describe one case of a 51-year-old male with an EMPSGC co-existing with mucinous carcinoma of the eyelid. The tumor was composed of dilated ducts with a smooth border and was partially filled with a papillary proliferation. Tumor cells were uniform, small-to-medium in size, and oval-to-polygonal with light eosinophilic cytoplasm. Nuclei were bland with diffusely stippled chromatin and inconspicuous nucleoli. Tumor cells expressed chromogranin, synaptophysin, estrogen and progesterone receptors, cytokeratin 7, and epithelial membrane antigen.

Cytologic Findings of Fine Needle Aspiration Biopsy of 23 Schwannomas / 대한세포병리학회지

In an attempt to better define the cytologic characteristics of schwannomas, we have reviewed aspirates and corresponding histologic sections from 23 schwannomas. Of this number, the original cytologic diagnoses were: schwannoma in 14 cases (61%), benign soft tissue tumor in 2 cases (9%), and insufficient specimen in 7 cases (30%). The cytologic findings common to all cases of schwannoma included fragments of tightly cohesive fascicles with variable cellularity and corresponding Antoni type A area. The Antoni type B area, consisting of scattered spindle cells and some histiocytes and lymphocytes against a myxoid background, was seen in 14 cases. Fibrillary stroma was seen in 12 cases. The tumor cells had spindle- or oval-shaped nuclei, with pointed ends and indistinct cell borders. Nuclear palisading was seen in 10 cases, and distinctive Verocay bodies were seen in 5 cases. In ancient schwannomas, there were no Verocay bodies. Most schwannomas have distinct cytomorphologic features that allow correct diagnosis. The major problem with fine needle aspiration cytology of these tumors is the high frequency of poor cellularity, particularly in lesions with cystic degeneration. Of 7 cases with insufficient specimen, 4 showed marked cystic changes and 1 showed marked hyaline changes on histologic sections. In conclusion, we believe that if cytopathologist reminds the situation such as cystic degeneration or hyaline degeneration, the correct diagnosis of the schwannoma will be easily made.