The Effect of Elapsed Time on the Quantity of mRNA in Skin: A Study to Evaluate the Potential Forensic Use of mRNA to Determine the Postmortem Interval / 대한법의학회지

Ribonucleic acid (RNA) has potential use in forensic science for the determination of postmortem interval. We report the first study on serial sampling of messenger RNA (mRNA) from surgical specimens to determine if there is a correlation between mRNA quantity and elapsed time. Skin tissues were collected from modified radical mastectomy specimens. After a defined period of time, bisected skin sections were cut and frozen in liquid nitrogen. Serial collection of the specimens was conducted, and frozen sections were obtained from all samples. Quantitative real-time reverse transcription-polymerase chain reaction was performed using the extracted RNA to measure the transcriptional activity of 2 selected housekeeping genes. The selected loci were mRNA sequences that exhibited time-dependent quantitative changes in a previous study. We collected 44 samples from 9 different patients, with 3-10 samples collected per patient. The amount of mRNA transcripts present in the serial samples showed a weak time-dependent correlation trend only in some cases. Further studies to evaluate different target mRNA sequences are necessary, as is exploration of additional methods to evaluate mRNA transcript degradation.

Pathology of Epstein-Barr Virus-Associated Gastric Carcinoma and Its Relationship to Prognosis

Among Epstein-Barr virus (EBV)-associated neoplasms, EBV-associated gastric carcinoma (EBVaGC) is the most common tumor worldwide. In contrast to the predominant site of occurrence of EBV-negative gastric carcinoma in the antrum, EBVaGC occurs most frequently in the proximal stomach, including the cardia, fundus and body. Microscopically, EBVaGC can be subclassified into three histological subtypes according to the host cellular immune responses: lymphoepithelioma-like carcinoma, carcinoma with Crohn's disease-like lymphoid reaction, and conventional-type adenocarcinoma. Recent studies have shown that patients with the lymphoepithelioma-like carcinoma subtype of EBVaGC have the best overall and disease-free survival, followed by Crohn's disease-like reactions, which in turn have better survival than patients with conventional-type adenocarcinoma. Histologic subclassifications of EBVaGCs are based on the differing degree and pattern of infl ammatory response and the extent of desmoplasia. Because these subclassifications appear to be a powerful prognostic parameter, further research into the underlying mechanisms of the cellular immune reaction in these pathologic subtypes of EBVaGCs may play a key role in understanding the innate immune response of patients with this highly aggressive carcinoma.

Histologic Features of ALK-Expressing Adenocarciomas of the Lung

PURPOSE: This study was designed to define the specific histologic features of anaplastic lymphoma kinase (ALK)-expressing pulmonary adenocarcinoma. MATERIALS AND METHODS: Of the 580 pulmonary adenocarcinomas diagnosed between March 2010 and February 2011, immunohistochemical staining for ALK was performed in 269 cases showing any suspicious histologic features in previous reports. The subtype according to the World Health Organization classification and the characteristic histologic features were re-evaluated in ALK-expressing cases. RESULTS: A total of 46 cases (7.9% of the 580 adenocarcinomas, 17.1% of the 269 studied cases) were positive for ALK. Among the 46 cases showing ALK positivity, 35 cases (76%) showed intra- and/or extra-cytoplasmic mucin. The most well-known characteristic finding associated with ALK, signet ring cells, was found in 18 cases (39.1%). Cribriform pattern with extracytoplasmic mucin was identified in five cases. In six cases, all three features were found. On the other hand, there were three other cases that did not show any of the aforementioned histologic features. In 12 lobectomy specimens, the most common histologic pattern was a solid pattern (five cases, 41.6%). CONCLUSION: Intra- and/or extra-cytoplasmic mucin, including signet ring cell appearance and a cribriform pattern with extracytoplasmic mucin, are characteristic features of ALK-expressing non-small cell lung cancer.

Micronodular Thymoma with Lymphoid Stroma: A Case Report

Micronodular thymoma with lymphoid stroma (MNT) is an extremely rare tumor and has not been reported in Korea. Herein, we report a case of MNT diagnosed in a 75 year-old male. The mass was incidentally identified on thoracic computer tomography (CT) during work-up for a cardiac mass. The resected thymic mass was ovoid and solid measuring 3.5x3 cm in size and showed homogenously white tan, solid and firm cut surface. Microscopically, the tumor had a thin fibrous capsule except small foci of invasion to thymic adipose tissue, and consisted of characteristic multiple discrete epithelial nodules in abundant lymphoid stroma. The epithelial nests anastomosed each other, forming a vague cord-like structure. The cells in the epithelial nests were bland, spindle to oval shape with relatively abundant cytoplasm, slightly vesicular chromatin and one definite nucleolus. The lymphoid stroma contained prominent germinal centers. No evidence of recurrence or metastasis has been found within 4 years of surgery.

Newly Formed Hepatic Masses in Children with Biliary Atresia after Kasai Hepatic Portoenterostomy

BACKGROUND: This report describes the clinicopathologic findings of six hepatic masses that developed after Kasai hepatic portoenterostomy (HPE) in six patients with longstanding biliary atresia (BA). METHODS: Hepatic masses were found in six of 55 pediatric patients who underwent liver transplantation for BA after Kasai HPE from 1997 to 2009. Clinicopathologic analysis was performed and immunohistochemical staining was carried out for CD34, smooth muscle actin (SMA) and cytokeratin 7. RESULTS: Of the six hepatic masses, two were diagnosed as focal nodular hyperplasia (FNH)-like lesions, two were large regenerative nodules (LRN), one was a mesenchymal hamartoma (MH) and one was a cholangiocarcinoma. The immunohistochemical staining findings for SMA and CD34 were more prominent for the FNH-like nodules than for the cirrhotic background liver. Dysplastic biliary epithelium arising from intestinal metaplasia was found in the cholangiocarcinoma. CONCLUSIONS: Our findings suggest that FNH-like lesions, LRNs and MH are the results of vascular hemodynamic changes after Kasai HPE and that cholangiocarcinoma is due to recurrent cholangitis after BA. All the lesions in this series must be included in the differential diagnosis of a newly formed hepatic mass in patients after portoenterostomy.

Pathologic Findings of Surgically Resected Nontuberculous Mycobacterial Pulmonary Infection

BACKGROUND: Surgical resection of the involved lung for nontuberculous mycobacteria (NTM) has become an important curative therapy. However, there is limited information on the histopathological features of NTM pulmonary disease in Korean patients with NTM infection. METHODS: We evaluated 51 specimens from 49 patients who were treated at our referral center from 2002 to 2009. RESULTS: Almost all the cases showed bronchiectasis with lymphocytic infiltration. Variable features of granulomatous inflammation were found; well-defined granulomas in the parenchyma (68.6%), pneumonia-like granulomatous lesions (49.0%) and granulomatous inflammation in the bronchial wall (41.2%) were identified. The microscopic findings of cavitary lesions (37.3%) showed that these lesions were composed of granulomas and necrosis. CONCLUSIONS: The differentiation of tuberculosis from NTM could not be accurately made based solely on the histological features. However, the airway centered tendency of NTM reflected an airborn etiology, and this could be correlated with the classification according to the radiological findings. In addition, coexisting constitutional lung diseases, and especially bronchiectasis, were suspected to be predisposing conditions for NTM organisms to colonize and progress to true NTM pulmonary disease.

Follicular Dendritic Cell Sarcoma of the Abdomen: the Imaging Findings

Follicular dendritic cell sarcoma is a rare neoplasm that originates from follicular dendritic cells in lymphoid follicles. This disease usually involves the lymph nodes, and especially the head and neck area. Rarely, extranodal sites may be affected, including tonsil, the oral cavity, liver, spleen and the gastrointestinal tract. We report here on the imaging findings of follicular dendritic cell sarcoma of the abdomen that involved the retroperitoneal lymph nodes and colon. It shows as a well-defined, enhancing homogenous mass with internal necrosis and regional lymphadenopathy.

Carney Triad in an Adult with Aggressive Behavior: The First Case in Korea

Carney triad is a rare syndrome of unknown etiology characterized by having at least two out of three following neoplasms: gastrointestinal stromal tumor, pulmonary chondroma and extra-adrenal paraganglioma. About 100 cases have been reported worldwide. We report a case of Carney triad in a 42-year-old woman presented with a gastrointestinal stromal tumor in the stomach and a malignant functioning paraganglioma in the retroperitoneum that was fatal five years after diagnosis. The gastrointestinal stromal tumor was diagnosed as intermediate-risk of aggressive behavior and diffusely positive for c-kit whereas the retroperitoneal paraganglioma was negative for c-kit. Genetic analyses showed no mutations of KIT, PDGFRA, SDHB, SDHC, and SDHD genes in both tumors. To our best knowledge, this is the first case of Carney triad in Korea.

Multidetector-Row CT Findings of Gastric Cystic Lymphangioma: A Case Report

Cystic lymphangioma is a rare benign submucosal tumor of the stomach thought to originate from sequestered lymphatic tissue that fails to communicate with the normal lymphatic system. The most commonly used method of evaluation for cystic lymphangioma of the stomach is an endoscopic ultrasonography. We report the multidetector-row computed tomography findings of a cystic lymphangioma of the stomach in a 46-year-old man along with a literature review.

Solitary Pulmonary Lymphangioma in an Adult: A Brief Case Report

Solitary pulmonary lymphangiomas are extremely rare. We report here on an unique case of solitary pulmonary lymphangioma in an adult. A well-circumscribed, 6 cm-sized, pleural based lesion with fluid attenuation was found in a 50-year-old Korean male. He had no previous history of disease or trauma. The wedge-resected lung revealed an ill-demarcated lesion with multiple microscopic cysts and the cystic walls had loose intervening stroma.