RESUMO
Malignant pericardial mesothelioma (MPM) is a rare tumour that arises from the mesothelial cells of the pericardium. No standard treatment has been established owing to a poor treatment response; therefore, MPM has a poor prognosis. We herein report a rare case of MPM in a 70-year-old man that was diagnosed immunohistopathologically using cell block sections of pericardial fluid and in which long-term survival for more than 3 years was achieved with only periodic pericardial drainage. Immunohistopathological staining investigations, especially BRCA1-associated protein 1 (BAP1) immunostaining using cell block sections of pericardial effusion, are effective in making a diagnosis of MPM. Well-differentiated papillary mesothelioma (WDPM) with BAP1 loss progresses to MPM in the long term, showing that BAP1 loss may induce phenotypical evolution of WDPM. BAP1 loss may also progress to malignant mesothelioma in situ and then to invasive mesothelioma. BAP1 immunohistochemistry should be considered for the early diagnosis of MPM.
RESUMO
BACKGROUND: Although glenohumeral instability is common, the mechanism of instability remains unclear. The purpose of this study was to quantitatively evaluate humeral head translation during active external rotation with abduction in patients with glenohumeral instability by use of 4-dimensional computed tomography scans. METHODS: Ten patients with unilateral glenohumeral instability with a positive fulcrum test were prospectively included in this study. Sequential computed tomography of bilateral shoulders during active external rotation at 90° of shoulder abduction was performed for 6 seconds at 5 frames per second. The 3-dimensional positions of the humeral head center in the anteroposterior, superoinferior, and mediolateral directions were calculated at 0°, 20°, 40°, 60°, and maximum shoulder abduction-external rotation from the starting position. Translation of the humeral head center from the starting position was evaluated using Dunnett multiple-comparison tests, and the differences between the affected and intact shoulders were assessed using Wilcoxon signed rank tests. RESULTS: The humeral head center translated posteriorly, inferiorly, and medially during glenohumeral external rotation with the shoulder in the abducted position on the intact side. However, the affected humeral head showed significantly less posterior translation (P = .028), greater inferior translation (P = .047), and less medial translation (P = .037) than the contralateral side. CONCLUSIONS: This study indicated that dysfunction of the anterior band of the inferior glenohumeral ligament causes decreased posterior, increased inferior, and decreased medial translation of the humeral head during active shoulder abduction-external rotation.
