Lymphangiomatous Polyp Arising From the Palatine Tonsil

Lymphangiomatous polyp arising from the palatine tonsil (LAPPT) is a very rare benign tumor that generally arises from a pedicle attached to the surface of the palatine tonsil and projecting into the oropharynx. ¹ Lymphangiomatous polyp arising from the palatine tonsil has been described as various diagnostic names in the previously reported literatures, such as angiomas, polypoid lymphangioma, hamartomatous tonsillar polyp, and lymphoid polyp, so it is difficult to determine the true incidence of LAPPTs. ² Lymphangiomatous polyp arising from the palatine tonsil is a rare clinical and pathologic entity for clinicians, but diagnosis is not so difficult if clinicians know the gross findings about LAPPT.

A 16-year-old girl was referred to our department with complaints of foreign body sensation in throat for 4 months. Also, she has complained of severe snoring with intermittent obstructive breathing since childhood. She had no other local or systemic symptoms. Physical examination revealed a smooth-surfaced, whitish, and polypoid mass with a pedicle extending from the right palatine tonsil into the oropharynx (Figure 1). The pedicle was seen arising from medial surface of the hypertrophied palatine tonsil. Examinations of other parts of oral cavity, nasopharynx, and larynx were normal and there was no palpable cervical lymphadenopathy. The patient underwent bilateral tonsillectomy including mass without complication and the patient had a normal postoperative course. Grossly, a 1.3 cm × 0.6 cm sized whitish, polypoid mass was found to be attached to the tonsil with a slender stalk (Figure 2). Histopathological results were consistent with a lymphangiomatous polyp (Figure 3). The remaining tonsillar tissue showed chronic inflammation. The patient was asymptomatic 1 year after surgery.

Figure 1.

On physical examination of the oral cavity, endoscopic photo showed a mass lesion extending from the right palatine tonsil to the left palatine tonsil (white arrows).

Figure 2.

A firm, smooth polypoid lesion, 1.3 cm × 0.6 cm in diameter, was found to be attached to the right tonsil with a slender stalk (white arrow).

Figure 3.

Histopathologic findings. The tumor is lined by squamous epithelium (SSE, stratified squamous epithelium) and aggregated by lymphoid tissue (H&E stain, ×40). (Right) Stroma was composed of fibrous tissue and numerous dilated lymphatic channel (arrow; H&E stain, ×100; left). H&E indicates hematoxylin and eosin.

Although the pathogenesis of LAPPT is not clearly known, 2 hypotheses have been proposed: one is chronic inflammation and associated obstruction of lymphatic channels and the other is isolated hamartomatous proliferation. ³ The detection of LAPPT may be incidental because the patients may be usually asymptomatic, but common presenting symptoms include dysphagia, dyspnea, foreign body sensation, sore throat, tonsillitis, and even a sense of mass depending on the size of the mass. ⁴ The diagnosis of LAPPT can be confirmed by the histopathologic findings, which are characterized by the surface stratified squamous epithelium and its stroma consists of different components that vary from loose to dense fibrous tissue and adipose tissue, dilated lymphatic channels, and various components of lymphoid tissue. ^4,5 However, we suggest that the gross characteristics of LAPPT in oral cavity examination are important for diagnosis. In gross appearance, LAPPT may be pinkish, smooth surfaced, and polypoid mass with a pedicle attached to the surface of the palatine tonsil and projecting into the oropharynx. Only one experience with gross appearance may be enough to diagnose. Lymphangiomatous polyp should be considered in the differential diagnosis of mass lesion arising from the palatine tonsil including lymphangiectasia, hemangioma, arteriovenous malformation, juvenile nasopharyngeal angiofibroma, fibroepithelial polyps, and papilloma. ² Complete surgical excision of the mass and the involved tonsil is the curative treatment of choice regarding the management of the LAPPT. ^2,4 In this case, we decided to perform bilateral tonsillectomy because the patient had severe snoring with intermittent obstructive sleep apnea. There have been no reported cases of disease recurrence or malignant transformation. ^2,6

In conclusion, clinicians should keep in mind that LAPPT should be taken into consideration in the differential diagnosis of a tonsillar mass and the gross appearance is thought to be helpful for differential diagnosis.