Subclinical Central Lymph Node Metastasis in Papillary Thyroid Microcarcinoma Evaluated as cT1aN0 by Preoperative Imaging Study / 대한갑상선학회지

BACKGROUND AND OBJECTIVES: Papillary thyroid microcarcinoma (PTMC) generally has a highly favorable prognosis, however reports show a 30-65% prevalence of subclinical central lymph node metastasis. Therefore, the role of elective central neck dissection in PTMC treatment remains controversial. Our study focused on preoperative features of clinically lymph node negative and intracapsular (cT1aN0) PTMC and the correlation of these features with subclinical central lymph node metastasis. MATERIALS AND METHODS: Of 584 PTC patients who underwent thyroidectomy at the Kosin University Gospel Hospital from January 2009 to July 2011, 219 patients with cT1aN0 PTMC were reviewed retrospectively. Pathologic results were reviewed and various clinicopathologic prognostic factors were investigated. RESULTS: Postoperative pathology report revealed capsular invasion of primary tumor in 77 patients (35.2%) and subclinical central lymph node metastasis in 62 patients (28.3%). Tumor of the isthmic location was an independent predictor of subclinical central lymph node metastasis by multivariate analysis while multifocality showed borderline significance. The presence of extrathyroidal extension (ETE), multifocality, and cervical lymph node metastasis were significantly related to PTMC of isthmus. Seven of the 14 subjects with PTMC of the isthmus (50%) had pretracheal lymph node metastasis showing significant correlation (p=0.001). CONCLUSION: Despite the absence of ETE and lymph node metastasis in the preoperative imaging studies, higher risk of subclinical central lymph node metastasis should be considered in PTMC with multifocality and tumor of the isthmus.

A Case of Granular Cell Tumor of the Colon Treated by Colonoscopy / 대한소화기내시경학회지

Granular cell tumor (GCT) is a relatively rare benign tumor that can be located anywhere throughout the body, but it is uncommon in the gastrointestinal tract, and especially in the colon and rectum. A 41-year-old man visited our hospital with a three-month history of intermittent abdominal discomfort at the left lower quadrant area. Colonoscopic examination revealed a hemispheric, submucosal lesion, about 1.5 x 1.2 cm in size, on the opposite side of the ileocecal valve in the proximal ascending colon. The tumor was removed by an endoscopic snare without any immediate complication. The pathologic findings revealed spindled or polygonal large cells that were positive for S-100, neuron-specific enolase and vimentin, and they were negative for smooth muscle actin and desmin, which was consistent with granular cell tumor. We report here on a case of granular cell tumor of the colon that was successfully treated with endoscopic polypectomy.

A Case of Carcinoid Tumors of the Stomach and Duodenum Treated by Endoscopy / 대한소화기내시경학회지

A carcinoid tumor is a slow growing, rare neoplasm arising from enterochromaffin cells with a malignant potential. A primary carcinoid tumor of the stomach and duodenum is uncommon. However, their prevalence has been increasing due to the widespread use of endoscopy. Recently, the use of endoscopic resection for the treatment of small carcinoid tumors is gradually increasing. To our knowledge, this is the first case report of synchronous carcinoid tumors in the stomach and duodenum. We report a case of small, multiple carcinoid tumors of the stomach and duodenum in a 58-year-old man that was endoscopically removed with a snare.

Differential Expression of CD34 and Smooth Muscle Actin in the Stroma of Small Lung Adenocarcinoma with Mixed Bronchioloalveolar and Invasive Components

BACKGROUND: Absence of CD34-positive fibroblasts was reported within the stroma associated with invasive carcinomas. Conversely, tumor-associated desmoplastic stroma is characterized by the presence of smooth muscle actin (SMA)-reactive myofibroblasts. The present study was undertaken in order to elucidate whether the different distributions of stromal CD34-positive fibroblasts and SMA-reactive myofibroblasts are sensitive or specific markers of tumor invasion in small lung adenocarcinomas. METHODS: Immunohistochemical stainings for CD34 and SMA were done in 37 peripheral adenocarcinomas less than 3.0 cm in diameter, including 16 adenocarcinomas with bronchioloalveolar carcinoma (BAC) and invasive components (mixed), and 21 invasive adenocarcinomas without BAC components (invasive). RESULTS: The fibroblasts within the BAC components of the mixed group were mainly CD34-positive (81.2%) and preferentially SMA-negative (56.3%). In contrast, the fibroblasts within the invasive components of the mixed group were mainly CD34-negative (75.0%) and SMApositive (87.5%). The stromal cells of the invasive group were mostly negative for CD34 (90.5%) and positive for SMA (95.3%). CONCLUSIONS: The loss of CD34 and the acquisition of SMA in the stromal cells within the tumor were related to tumor invasion (p<0.05). Thus, expression patterns of CD34 and SMA can be used to detect small foci of early stromal invasion in adenocarcinomas of the lung.