Nasopharyngeal Inflammatory Polyp With Pseudo-Lymphangiomatous Features: A Case Report

Nasopharyngeal masses encompass a broad differential diagnosis, including inflammatory, congenital and neoplastic lesions. Lymphangiomas are rare benign lymphatic malformations and are infrequently reported in the nasopharynx. We present an unusual case of an inflammatory nasopharyngeal polyp with pseudolymphangiomatous histological features that initially mimicked lymphangioma. A 22-year-old male presented with recurrent nasal obstruction. Endoscopy demonstrated an atypical polypoid lesion protruding through the left choana. Computed tomography showed a 30 × 22 × 20 mm lesion arising from the left superior turbinate and extending into the nasopharynx, without bone destruction. Endoscopic resection was performed. Initial histology showed multiple dilated fluid-filled spaces within densely hyalinised stroma, with CD31 positivity, raising concern for lymphangioma. The ERG-negative profile was atypical, and repeat immunohistochemistry with CD31, D2-40 and CD34 failed to demonstrate endothelial lining of the spaces. The fluid-filled spaces were, therefore, interpreted as stromal oedema rather than true lymphatic channels, and the diagnosis was revised to an oedematous inflammatory polyp with pseudolymphangiomatous appearance. Postoperative follow-up was arranged, but the patient did not attend. Our targeted literature review did not identify previous reports of pseudolymphangiomatous change in inflammatory nasal polyps. This case expands the recognised histopathological spectrum of inflammatory sinonasal polyps and underscores the need for cautious clinicopathological interpretation of rare nasopharyngeal presentations.