Morphology of Thymic Remnants Removed after Video-Assisted Thoracoscopic Extended Thymectomy in Patients with Thymomatous Myasthenia Gravis
On a total of 67 patients with Myasthenia Gravis (MG) that had a Video-Assisted Thoracoscopic Extended Thymectomy (VATET) for removal of the thymus gland and cervical and anterior mediastinal fat tissue, 12 revealed a thymoma. Nine patients with capsulated non-invasive thymoma were studied for detection of thymic remnants in cervical and pre-pericardial fat tissue. Six out of nine subjects showed thymic remnants that in half of them demonstrated lymphoid follicular hyperplasia Immunohistochemical characterization of atrophic thymic remnants showed small T-lymphocytes (CD1a; CD3) and rare epithelial cells (EMA; Cytokeratin and LN3). Thymic remnants with lymphoid follicular hyperplasia showed germinal centres positively stained for LN1 (CDw75). Since the last alteration has been considered an important cause of failure of surgical treatment of MG, an accurate investigation and removal of all possible thymic remnants together with the proper thymus may be performed.
KeywordsLymphoid Hyperplasia Thymic Tissue Thymus Gland Thymic Epithelial Tumor Invasive Thymoma
Unable to display preview. Download preview PDF.
- 4.Fukai I, Funato Y, Mizuno T, Hashimoto T, Masaoka A Distribution of thymic tissue in the mediastinal adipose tisssue. J Thorac Cardivasc Surg 101, 1099–1122; 1991.Google Scholar
- 5.Jaretzky A, Wolff M Maximal thymectomy for myasthenia gravis. J Thorac Cardivasc Surg 96, 711–716; 1988.Google Scholar
- 6.Jaretzky A, Penn AS, Younger DS, Wolff M, Rowland LP Maximal thymectomy for myasthenia gravis. J Thorac Cardivasc Surg 95, 747–757; 1988.Google Scholar
- 9.Masaoka A, Nagaoka Y, Yotake Y Distribution of thymic tissue at the anterior mediastinum. J Thorac Cardivasc Surg 4, 747–716; 1975.Google Scholar
- 11.Rosai J, Levine GD Tumors of the thymus. In Atlas of tumor pathology. Second series. Fasc 13. Washington DC 1976 Armed Forced Institute of PathologyGoogle Scholar
- 13.Scelsi R, Ferro MT, Scelsi L, Novellino L, Mantegazza R, Cornelio F, Porta M, Longoni M, Pezzuoli G. Detection and morphology of thymic remnants after VATET in patients with myasthenia gravis Int Surg 80, 126–131; 1995.Google Scholar
- 14.Shi Z.R., Itkowitz S.H. & Kin Y.S. A comparison of three immunoperoxidase techniques for antigen detection in colorectal carcinoma tissues. Journal of Histochemistry, 32, 219–229, 1988.Google Scholar
- 16.Wilkins EW, Edmunds LH, Castleman B Cases of thymoma at the Massachussets general Hospital J Thorac Cardivasc Surg 52, 322–330; 1966.Google Scholar