J Pathol Transl Med.  2019 Nov;53(6):403-406. 10.4132/jptm.2019.06.23.

Adenocarcinoma Arising in an Ectopic Hamartomatous Thymoma with HER2 Overexpression

• Oh H
• Kim E
• Ahn B
• Lee JH
• Lee Y
• Chae YS
• Kim CH
• Lee YJ

• KMID: 2465441
• DOI: http://doi.org/10.4132/jptm.2019.06.23

Abstract

No abstract available.

MeSH Terms

Adenocarcinoma*
Thymoma*

Figure

• 

  Fig. 1. Representative images of adenocarcinoma arising in ectopic hamartomatous thymoma (EHT). (A) Gross findings show a well-circumscribed, multi-lobulated, whitish-gray, heterogenous, solid mass with focal cystic changes. (B) The periphery of the tumor is composed of epithelial cells, spindle cells and adipose tissue, typical features of EHT. (C) The area of atypical glandular proliferation (right) is distinct from the background EHT (left). (D) The malignant components have large pleomorphic nuclei with prominent nucleoli and abundant eosinophilic cytoplasm. (E) Androgenic receptor immunostain shows nuclear positivity in both the benign and malignant areas. (F) HER2 overexpression is only identified in the malignant portion (right).

Reference

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