Young Chae Chu

Reclassifying Formerly Indeterminate Thyroid FNAs Using the Bethesda System Reduces the Number of Inconclusive Cases

Objective: To evaluate the effectiveness of the Bethesda System for Reporting Thyroid Cytopathology (BSRTC) and to analyze the causes of unclear diagnoses following BSRTC adoption. Study Design: According to the BSRTC, we reclassified cytologic samples originally diagnosed as ‘indeterminate’ with sequential surgical resection. Then, we analyzed the causes of cases, which were recategorized as ‘atypia undetermined significance/follicular lesion of undetermined significance (AUS/FLUS)’. Results: According to the BSRTC, 154 ‘indeterminate’ cases were reclassified as follows: unsatisfactory, n = 5 (3.2%); benign, n = 43 (27.9%); AUS/FLUS, n = 77 (50.0%); suspicious for a follicular neoplasm, n = 7 (7.1%); suspicious for a Hürthle cell neoplasm, n = 4 (2.6%); suspicious for malignancy, n = 15 (9.7%), and malignancy, n = 3 (1.9%). Then, the AUS/FLUS group was analyzed according to the scenarios proposed by the BSRTC. Fifty-nine (58.9%) cases of AUS/FLUS were due to suboptimal preparation. In addition, papillary microcarcinoma and coexisting Hashimoto’s thyroiditis caused inconclusive diagnoses. Conclusion: The BSRTC can be easily applied to thyroid fine-needle aspiration. We were able to reclassify indeterminate thyroid nodules into more detailed categories and thus reduce the number of cases classified as indeterminate. However, suboptimal preparation, papillary microcarcinoma, and coexisting Hashimoto’s thyroiditis precluded cytopathologists from making definitive diagnoses.

Endometrial stromal sarcoma of the small bowel: a case report and review of literature

Endometrial stromal sarcoma (ESS) is a rare mesenchymal neoplasm of the uterus, which is predominantly composed of endometrial stromal cells. When this feature is encountered in the extragenital area, the diagnosis is sometimes difficult especially if endometriosis is not present. We report a case of ESS arising in the small bowel without associated endometriosis in a 75-year-old woman and review the literatures for 16 cases of extrauterine extraovarian ESS. The most common site of the extrauterine extraovarian ESS is the gastrointestinal tract (8/16 cases). It is intimately associated with endometriosis (12/16 cases) as the case of ovarian ESS. Most ESSs were immunoreactive for CD10 (5/5 cases), progesterone receptor (10/10 cases), and estrogen receptor (9/11 cases), and negative for CD34 (0/7 cases). It may have a higher tendency for dissemination beyond its site of origin (12/16 cases) than its uterine counterpart. In conclusion, a careful morphological examination combined with immunohistochemical studies and consideration of ESS in the differential diagnosis would help in obtaining an accurate diagnosis in these rare circumstances.

Extrapulmonary Small Cell Carcinoma of the Liver: Clinicopathological and Immunohistochemical Findings

Patients with primary small cell carcinoma of the liver have rarely been described in medical literature. Knowledge of clinical, pathological and immunohistochemical properties remains limited. We described an 82-year-old female patient with primary small cell carcinoma of the liver. Histologically, the tumor showed typical morphology of a pulmonary small cell carcinoma. Immunohistochemically, the tumor revealed neuroendocrine differentiation; positive reaction for chromogranin, synaptophysin, CD56, and neuron specific enolase. The tumor was also positive for TTF-1 and c-kit but completely negative for hepatocyte, carcinoembryonic antigen, cytokeratin 7; 19; and 20. Herein, we discussed the clinical, pathological and immunohistochemical findings of extrapulmonary small cell carcinoma of the liver and reviewed the relevant literature.

Myositis ossificans of the chest wall simulating malignant neoplasm

Myositis ossificans originating from the chest wall is extremely rare. We report a case of myositis ossificans occurring in a young woman with progressive painful swelling in the chest wall. Preoperative examination suggested a malignant neoplasm originating from soft tissue. Although rare, myositis ossificans is one of the potential causes of painful swelling in the chest wall, and can be mistaken for a malignant neoplasm.

PPARγ Agonist and Angiotensin II Receptor Antagonist Ameliorate Renal Tubulointerstitial Fibrosis

The peroxisome proliferator activated receptor (PPAR)γ agonist is used as antidiabetic agent with antihyperglycemic and antihyperinsulinemic actions. Beyond these actions, antifibrotic effects have been reported. We examined antifibrotic effects of PPARγ agonist and interaction with angiotensin receptor antagonist in the unilateral ureteral obstruction (UUO) model. After UUO, mice were divided to four groups: no treatment (CONT), pioglitazone treatment, L158809 treatment, and L158809+ pioglitazone treatment. On day 14, CONT mice showed severe fibrosis and all treated mice showed decreased fibrosis. The immunohistochmistry of PAI-1, F4/80 and p-Smad2 demonstrated that their expressions were increased in CONT group and decreased in the all treated groups compared to CONT. PAI-1 and p-Smad2 determined from Western blotting, among treated groups, was decreased compared to CONT group. The expression of TGF-β1 from real time RT PCR showed markedly increased in the CONT group and decreased in all treated groups compared to CONT. These data suggest the pioglitazone inhibited tubulointerstitial fibrosis, however, the synergism between pioglitazone and L158809 is not clear. Considering decreased expression of PAI-1 and TGF-β/Smad2 in the treated groups, PAI-1 and TGF-β are likely linked to the decreased renal tubulointerstitial fibrosis. According to these results, the PPARγ agonist might be used in the treatment of renal fibrotic disease.

Cytologic Evaluation of Low Grade Transitional Cell Carcinoma and Instrument Artifact in Bladder Washings

OBJECTIVE To identify key cytologic features for the separation of low grade transitional cell carcinomas (TCCs) from nonneoplastic lesions in bladder washings. STUDY DESIGN The cytomorphologic features of 95 bladder washing specimens showing papillary fragments, which included 50 low grade TCCs and 45 nonneoplastic lesions, were reviewed retrospectively. RESULTS Bladder washings from low grade TCCs showed papillary and irregular groups of cells with ragged borders, cytoplasmic homogeneity and subtle nuclear changes, such as increased nuclear/cytoplasmic ratio and irregular nuclear border. Bladder washings after instrumentation from nonneoplastic lesions of the bladder showed cellular specimens with cohesive, ball-shaped and papillary clusters with smooth borders lined with a denser-staining cytoplasmic collar. Reactive urothelial cells often displayed loose aggregates with irregular borders but no cytoplasmic collar. CONCLUSION In bladder washing cytology, nuclear changes and cytoplasmic homogeneity play a major role in the diagnosis of carcinoma.

The clinical significance of atypia in thyroid fine-needle aspiration

Fine-needle aspiration cytology (FNAC) of thyroid nodules has become the primary diagnostic tool in the evaluation of thyroid nodules. However, the diagnostic utility of thyroid cytology may be limited by the presence of atypical cytologic patterns. In patients with atypical cytology in FNAC, treatment concept is not established. The purpose of this study is to correlate subcategories of atypical cytology of thyroid gland with final histologic diagnoses, and to help develop a treatment plan for thyroid nodules. We retrospectively reviewed 133 specimens of patients with atypical cytology of thyroid nodule according to preoperative FNAC. The atypical cytologic patterns were classified and divided into three groups: follicular neoplasm with nuclear atypia (FNA), nodular hyperplasia with nuclear atypia (NHA), possible papillary carcinoma (PP). Then we investigated the malignancy rates of each group. Among the 133 specimens with atypical cytology, 43 cases (32.3%) were proved to be malignant. Of the 97 cases in the FNA group, 29.9% were malignant. In the NHA and PP groups, 23.1 and 47.8% were malignant, respectively. However, there was no statistical significance in the incidence of malignancy among the three groups. There was also no statistical difference among all groups, with regard to lymph node metastasis and recurrence. In conclusion, if aspirates manifest atypical cytologic pattern, surgery should be considered, especially if the results are categorized as PP. Intraoperative frozen section should be confirmed and the extent of resection should be determined by final pathology.

Radiation-induced angiogenic signaling pathway in endothelial cells obtained from normal and cancer tissue of human breast

Despite strong possibility that endothelial cells (ECs) of tumors and normal tissues may differ in various aspects, most previous studies on ECs have used normal cells. Here, we purified ECs from tumorous and normal human breast tissues, and studied the effect of radiation on angiogenesis and relevant molecular mechanisms in these cells. We found that in normal tissue-derived ECs (NECs), 4 Gy irradiation increased tube formation, matrix metalloproteinase 2 (MMP-2) expression and extracellular signal-regulated kinase (ERK) pathway activation. In cancer-derived ECs (CECs), however, 4 Gy irradiation significantly reduced tube formation, increased the production of angiostatin and interleukin-6 (IL-6), and upregulated AKT and c-Jun N-terminal kinase (JNK) pathway activation. Knockdown experiments showed that siMMP-2 efficiently inhibited tube formation by irradiated NECs, whereas siPlasminogen effectively attenuated the radiation-induced suppression of tube formation and the upregulation of angiostatin in CECs. Moreover, siIL-6 clearly inhibited the radiation-induced generation of angiostatin in CECs. Inhibition of ERK with a pharmacological inhibitor or small interfering RNAs (siRNAs) markedly suppressed the radiation-induced tube formation and MMP-2 upregulation in NECs, whereas the inhibition of either AKT or JNK with pharmacological inhibitor or siRNA treatment of CECs markedly attenuated the inhibition of tube formation and the upregulation of angiostatin and IL-6 caused by 4 Gy irradiation. These observations collectively demonstrate that there are distinct differences in the radiation responses of NECs and CECs, and might provide important clues for improving the efficacy of radiation therapy.

Hyalinizing spindle cell tumor with giant rosettes arising in the lung: report of a case with FUS-CREB3L2 fusion transcripts.

Hyalinizing spindle cell tumor with giant rosettes (HSCT) is a very uncommon mesenchymal tumor that has similar morphological and biological features to the low‐grade fibromyxoid sarcoma (LGFMS). Lung involvement of HSCT is extremely rare, and only one case has been reported in the English‐language literature. Reported herein is a case of primary pulmonary HSCT that had FUS‐CREB3L2 fusion transcripts, a product of characteristic chromosomal abnormality t(7;16)(q33;p11) of HSCT and LGFMS. The patient was a 50‐year‐old woman who had a large solitary mass in the lung. Histologically, it was composed of bland spindle cells with variable cellularity deposited in a densely hyalinized stroma alternating with myxoid areas. Characteristic collagen rosettes were scattered in the cellular areas. Reverse transcription–polymerase chain reaction (RT‐PCR) assay using formalin‐fixed, paraffin‐embedded tissue detected FUS‐CREB3L2 fusion transcripts. Despite its bland morphology, it is known as low‐grade sarcoma and its recognition in the lung would be helpful for accurate diagnosis and proper management of this rare tumor. RT‐PCR for detection of FUS‐CREB3L2 fusion transcripts is a useful method for differential diagnosis of primary pulmonary HSCT.

Clinicopathologic and Molecular Characteristics of Lung Adenocarcinoma Arising in Young Patients

Lung cancer rarely occurs in young patients. Recent studies have demonstrated that epidemiologic data are closely correlated to some molecular characteristics. We investigated the clinicopathologic characteristics of lung adenocarcinoma in young patients and evaluated immunohistochemically detected epidermal growth factor receptor (EGFR) mutation status and anaplastic lymphoma kinase (ALK) positivity. Among lung adenocarcinoma patients, 31 cases were of the ≤ 40 yr-old group and 261 cases of > 50 yr-old group. Young patients were more likely to be females (67.7% vs 40.2%), and nonsmokers (58.1% vs 45.2%) and more often had high TNM stage (stage IV was 80.6% vs 52.1%) and had a high rate of distant metastasis (51.6% vs 28.0%) compared with older patients. The signet ring cell feature was more common (25.8% vs 11.5%) and lepidic growth pattern was rarely present (3.2% vs 16.5%) in the adenocarcinoma of young patients. There was no significant survival difference between the two age groups. The rate of EGFR mutation status and ALK positivity did not show a statistical difference between two groups. In conclusion, lung adenocarcinoma of young patients demonstrates distinct pathologic features with frequent presence of a signet ring cell feature and rare occurrence of lepidic growth pattern. Further investigation for other genetic abnormalities would be needed.