HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Personal Folders Download to citation manager Author home page(s): Jun Nakajima Shinichi Takamoto Permission Requests Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Nakajima, J. Articles by Murakawa, T. Search for Related Content PubMed PubMed Citation Articles by Nakajima, J. Articles by Murakawa, T.

Eur J Cardiothorac Surg 2000;18:287-292
© 2000 Elsevier Science NL

Flow cytometric analysis of lymphoid cells in thymic epithelial neoplasms

Department of Cardiothoracic Surgery, Faculty of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan

Received 6 September 1999; received in revised form 25 May 2000; accepted 28 June 2000.

Corresponding author. Tel.: +81-3-3815-5411 extn. 33321; fax: +81-3-5684-3989
e-mail: nakajima-tho{at}h.u-tokyo.ac.jp

Objective: There have been conflicts concerning the criteria for diagnosing malignant epithelial neoplasms of thymic origin. To differentiate thymic carcinomas from thymomas, the maturation stage of T-lineage lymphoid cells infiltrating thymomas and thymic carcinomas was examined by flow cytometry to associate it with the degree of tumor malignancy. Methods: Multidimensional flow cytometric analysis was performed on the lymphoid cells extracted from 27 thymic epithelial neoplasms (14 encapsulated thymomas, ten invasive thymomas, and three thymic carcinomas) by using anti-CD3, -CD4, -CD8, -CD10, -CD20, -CD38, -CD45RA, and -CD45RO monoclonal antibodies. Results: CD4 and CD8 were co-expressed on 76.8% of the lymphoid cells in encapsulated thymoma (N=14), 59.2% in invasive thymoma (N=10), and 6.7% in thymic cancer (N=3). The percentage of CD4- or CD8- single positive cells was 11.4% in encapsulated thymoma, 23.9% in invasive thymoma, and 77.7% in thymic cancer. The percentage of CD10-positive cells was 20.8% in encapsulated thymoma, 13.2% in invasive thymoma, and 6.0% in thymic cancer. The percentage of CD20-positive cell was 2.6% in encapsulated thymoma, 3.3% in invasive thymoma, and 31.6% in thymic cancer. There were significant statistical differences in the percentages of CD4/CD8 double positive cells, CD4- or CD8-single positive cells, CD10-positive cells and CD20-positive cells among the three groups. Two cases classified as invasive thymoma by pathohistological examination, however, showed the infiltration of mature lymphocytes like as thymic cancers. Conclusions: CD4+CD8+ or CD10+ T-lineage cells were the most reliable markers of the benignancy of thymic epithelial tumors. CD4- or CD8-single positive cells or CD20-positive cells were characteristic in thymic carcinoma. Flow cytometry on the maturity of lymphoid cells infiltrating thymic epithelial tumors was feasible for determining their degree of malignancy. Some invasive thymomas showed the intermediate characteristics with thymomatous epithelia and mature lymphoid cells.

Key Words: Thymoma • Thymus neoplasms • Flow cytometry • CD4-positive lymphocytes • CD8-positive lymphocytes • CD10

This article has been cited by other articles:

				J. Nakajima, J. Matsumoto, E. Takeuchi, T. Fukami, and S. Takamoto Rearrangement of T-Cell Receptor Beta and Gamma Genes in Thymoma Asian Cardiovasc Thorac Ann, June 1, 2005; 13(2): 149 - 152. [Abstract] [Full Text] [PDF]