Clinicopathological and EBV analysis of respiratory epithelial adenomatoid hamartoma

Abstract

Background: To investigate the clinicopathological characteristics of respiratory epithelial adenomatoid hamartoma (REAH) in residents of Southern China and to study the correlation between REAH and Epstein-Barr virus (EBV).

Methods: Clinicopathological data of 53 cases of REAH were retrospectively analyzed. The immunoreactivity for CK 7, CK20, CEA, p53, and Ki-67, Alcian blue-periodic acid-Schiff (AB-PAS) staining and in situ hybridization for EBV-encoded RNA (EBER) were carried out.

Results: REAH lesions were covered with ciliated columnar epithelium and proliferation of subepithelial glands, which were positive for CK7, and negative for CK20, CEA, and p53. Goblet cell metaplasia was stained blue by AB-PAS. The frequency of EBER positive cases in REAH located in nasopharynx was 27.78%, compared with that in the nasal cavity (15.79%) and paranasal sinuses (12.50%), there were no statistical differences.

Conclusions: REAH is an uncommon entity with distinctive morphologic features and EBV may have nothing to do with REAH.

Virtual slides: The virtual slide(s) for this article can be found here:http://www.diagnosticpathology.diagnomx.eu/vs/5875687401178748.

Figure 1

Computed tomography scans of REAH. A. Axial CT showing soft tissue masses in both nasal cavities, mucosa in maxillary sinus, ethmoid sinus thickening in some extent. B. Additional CT of maxilla. Additional CT Note occlusion of right posterior choana and nasopharynx by mass.

Figure 2

Respiratory epithelial adenomatoid hamartoma. A. The glands proliferated with various sizes (hematoxylin-eosin, 20×). B. The glands were lined by ciliated respiratory epithelium (hematoxylin-eosin, 20×). C. Most of the ciliated respiratory epithelial are metaplastic goblet cells (hematoxylin-eosin, 40×). D. The glands were surround by thick eosinophilic and hyalinizated basement membranes (hematoxylin-eosin, 20×).

Figure 3

Representative immunohistochemical staining results of REAH. A. REAH stained with cytokeratin 7 shows diffuse predominantly strong staining of the glandular epithelium. B. p63 outlining the basal cell layers around glands in REAH. C. Ki-67 staining was localized to the basal layer with a labeling index less than 1%. D. The distinctive hyalinized basement membrane that surrounds the ciliated epithelium was highlighted by Collagen IV.

Figure 4

Alcian blue–periodic acid–Schiff Histochemical Staining. Compared with the respiratory epithelium of normal tissue from the nasal cavity mucosa (B), more mucins took up the blue AB-PAS stain in the glandular epithelium of REAH (A).

Figure 5

Epstein-Barr virus–encoded RNA (EBER) in-situ hybridization (ISH) of REAH. Black/dark brown signal is localized to the nuclei of affected cells. A (nasal cavity), B (paranasal sinuses) and C (nasopharynx) showing REAH with rare positive cell for EBER. D. Results of EBER positive rate compared with that of corresponding normal tissue.