Multilocular thymic cyst with epithelioid granulomata of unknown etiology: a radiologic and histopathologic correlation.

Thymic cysts (congenital or acquired) are believed to account for 3% to 5% of all mediastinal masses. Multilocular thymic cysts are an acquired reactive inflammatory process arising within the thymus gland and are less common than the congenital unilocular type. Multilocular cysts have been reported in association with a variety of neoplastic, autoimmune, and infectious conditions. We report a case of a 23-year-old white man who presented with a 2-week history of progressive right-sided shoulder and chest pain. He was found to have an anterior mediastinal mass involving the thymus. This case of multilocular thymic cyst is particularly unique due to the presence of abundant epithelioid granulomata within the cyst, a finding that has not previously been emphasized as a histologic feature of these lesions, and one that expands the histopathologic differential diagnosis, warranting exclusion of infectious and autoimmune etiologies.

BCL-6 expression in mesenchymal tumours: an immunohistochemical and fluorescence in situ hybridisation study.

The BCL-6 proto-oncogene encodes a transcriptional repressor protein. Among normal tissues, BCL-6 expression is confined to germinal center B-cells and a subpopulation of T-helper cells. Little is known about BCL-6 expression in mesenchymal tissues. We examined a series of solitary fibrous tumor (SFT) and other mesenchymal tumors for BCL-6 expression. Immunohistochemistry for BCL-6 was performed on 64 mesenchymal tumors [26 SFT (19 benign/uncertain, 7 malignant), 6 synovial sarcomas (SS), 5 gastrointestinal stromal tumors (GIST), 5 malignant peripheral nerve sheath tumors (MPNST), 5 leiomyosarcomas (LMS), 9 leiomyomas (LM) 4 desmoid tumors (DT), 4 perineuriomas (PN)]. Nuclear immunoreactivity was considered positive. Six BCL-6 positive SFT were also tested for BCL-6 gene rearrangement/amplification by FISH. Nuclear expression of BCL-6 was seen in 13/26 SFT, 5/5 LMS, 1/9 LM, 5/6 SS, 1/5 GIST, 1/5 MPNST, 1/4 PN, and 0/5 DT. BCL-6 expression was significantly more frequent in malignant (6/7) as compared with benign/uncertain SFT (6/19) (p=0.02) and in LMS (5/5) as compared with LM (1/9) (p=0.003). FISH for BCL-6 rearrangement/amplification was negative in all tested cases. We have observed BCL-6 expression in 50% or more of SFT, SS, and LMS, and in a lesser percentage of LM, GIST, MPNST and PN. Significantly more frequent expression of BCL-6 in malignant compared with benign/uncertain SFT and in LMS compared with LM suggests abnormalities in the BCL-6 signaling pathway may contribute to malignant transformation in at least some mesenchymal tumors. It is unlikely that BCL-6 expression in mesenchymal tumors is due to BCL-6 gene amplification or rearrangement.

Adamantinoma with plasmacytoid features: expanding the spectrum of a diagnostically challenging entity.

Adamantinoma is a rare neoplasm that characteristically involves the tibia. In many instances, typical location within the tibia, very slow course, and a typical radiographic appearance can strongly suggest the correct diagnosis. We present a case that has both unusual radiographic findings and uncharacteristic histology. In this case, radiologic imaging showed a poorly defined lytic lesion within the distal, lateral tibia extending to the joint with central necrosis, overlying periosteal reaction and possible tumor spread into soft tissue. The histology of this lesion showed pronounced vascularity and surrounding large neoplastic cells with plasmacytoid morphology. The combination of these features led to an initial misdiagnosis as metastatic carcinoma from unknown primary.

An Assessment of the Impact of Multimedia, Technology-Based Learning Tools on the Cardiac Auscultation Skills of Third-Year Medical Students.

BACKGROUND: Previous studies have shown that medical students and post-graduate trainees need to improve their proficiency in cardiac auscultation. Technologic advances have created new learner-centered opportunities to enhance proficiency in this important physical examination skill. OBJECTIVES: We sought to determine if technology-based, self-directed learning tools improved the cardiac auscultation skills of third-year medical students. METHODS: Sixteen (16) third-year medical (M3) students were exposed to three educational inter-ventions: a one-hour cardiac auscultation lecture that featured computer-generated heart sounds, a PDA-based heart sounds/murmur form and a web-based cardiac auscultation program. Thirteen (13) internal medicine (IM) residents who served as a comparison group attended a cardiac auscultation lecture identical in content and format to the student lecture. At the end of the study period, we evaluated the ability of both groups to accurately identify heart sounds and cardiac murmurs via a twelve-item performance-based examination utilizing computer-generated heart sounds. RESULTS: Following our teaching interventions, findingsM3 students correctly identified 80% of the computer-simulated heart sounds/murmurs while the comparison group of IM residents accurately detected 60% of the same cardiac findings (p<. 005). CONCLUSIONS: The combination of traditional lecture and multi-media, technology-based, self-directed learning tools appears to be an effective and efficient strategy for teaching and reinforcing cardiac auscultation skills to third year medical students.