Respiratory Epithelial Adenomatoid Hamartoma: A Review

Abstract

Respiratory epithelial adenomatoid hamartoma (REAH) is an uncommon lesion of the upper aerodigestive tract first described by Wenig and Heffner in 1995 as prominent glandular proliferations lined by ciliated respiratory epithelium originating from the surface epithelium. The entity is seen most often in male adults. Clinically the lesion presents as a polypoid mass, often in one or both nasal cavities, though other locations have been described. While REAH is benign, awareness and recognition of the lesion is important because it can be easily confused grossly and microscopically with more threatening tumors such as inverted papilloma and sinonasal carcinoma. The literature of REAH is reviewed with detail paid to the histologic diagnosis. The clinical presentation, radiologic findings, and differential diagnosis are also described.

Respiratory Epithelial Adenomatoid Hamartoma and Inflammatory Nasal Polyps Arising from the Different Sides of the Nasal Cavity: A Case Report

“…The main differential diagnostic problems with respect to REAH are nasal polyposis, inverted papilloma, and adenocarcinoma (10). REAH can be misdiagnosed as an inflammatory polyp because of its morphological and clinical similarities.…”

“…In contrast, inflammatory nasal polyps show the proliferation of pseudostratified respiratory epithelium with basement membrane thickening and stromal fibroblast proliferation and edema, with strong eosinophil, lymphocyte, and plasma cell tissue infiltration. Glandular proliferation can be found in nasal polyposis, but abnormal submucosal proliferation of the surface respiratory epithelium is more typically observed in REAH (9,10). Although inverted papillomas often have a grossly polypoid appearance, they differ from "true" nasal polyps and REAHs.…”

Nasal Cavity Masses Resembling Chondro-osseous Respiratory Epithelial Adenomatoid Hamartomas in 3 Dogs

“…In addition to the diagnostic criteria previously described, several histologic features were present in the canine masses that are common but not consistently present in REAH in people, including prominent glandular dilation with abundant mucinous and eosinophilic luminal contents, as well as seromucinous gland proliferation. 3 This study presents the first descriptions of COREAH-like masses in dogs. These findings present an additional differential for nasal cavity masses in dogs.…”

“…3 In the 4 published human cases of COREAH, however, 1 had recurrence at 1-year postresection; 2 did not have postresection follow-up information; and 1 was free of recurrence at 6-month postresection.…”

“…7,8 In human patients, REAH occurs in the nasal cavity, paranasal sinuses, and nasopharynx. 3,8 Grossly, REAH masses tend to have a polypoid organization. The polyps are soft to firm and yellow to white, sometimes with an edematous appearance.…”