J Pathol Transl Med.  2015 Jan;49(1):75-77. 10.4132/jptm.2014.10.27.

A Rare Case of Mixed Type A Thymoma and Micronodular Thymoma with Lymphoid Stroma

• Cha YJ
• Han J
• Kim J
• Lee KS
• Shim YM

• KMID: 2381357
• DOI: http://doi.org/10.4132/jptm.2014.10.27

Abstract

No abstract available.

MeSH Terms

Thymoma*

Figure

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  Fig. 1. Mixed Type A Thymoma and Micronodular Thymoma with Lymphoid Stroma. (A) Chest computed tomography imaging demonstrates a lobulated mass in the right anterior mediastinum. (B) Grossly, the tumor is encapsulated with a thin fibrous capsule, and is composed of vague nodules with tiny internodular micronodules, which matched with both type A thymoma (capital A on figure) and micronodular thymoma (arrowheads). (C) A microscopic area of infiltrative growth into fat tissue is noted. (D) A gradual transition is found between type A thymoma and micronodular thymoma with lymphoid stroma (MNTLS). (E) The MNTLS tissue has epithelial micronodules arranged in pseudorosettes that are separated by lymphoid stroma. (F) The tumor cells are strongly positive for cytokeratin, whereas lymphoid stroma lacks any epithelial component. (G) Lymphoid stroma is diffusely positive for CD5. (H) Together with type A thymoma, the epithelial component of MNTLS is positive for Bcl-2. Lymphoid stroma, except for within germinal centers, also is positive for Bcl-2.

Reference

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