CLINICAL CASE REPORT OF A LARGE ANTROCHOANAL POLYP

CASE REPORT CLINICAL CASE REPORT OF A LARGE ANTROCHOANAL POLYP Cveta Špadijer-Mirković1, Aleksandar Perić1, Biserka Vukomanović-Đurđević2, Ivan Stanojević3 Department of Otorhinolaryngology, Rhinology Unit1, Institute of Pathology2, Institute of Medical Research3, Faculty of Medicine, Military Medical Academy, Belgrade, Serbia Summary: Antrochoanal polyps are benign lesions originating from the mucosa of the maxillary sinus. Nasal obstruction and rhinorrhea are their main symptoms. Their endoscopical and radiological appearance makes them relatively easy to diagnose. These polyps are usually presented unilaterally, although bilateral presentation is also possible. We described two cases of atypically giant antrochoanal polyps: in a 15-year-old child and in a 38-year-old man. In both cases, the diagnosis was done by nasal endoscopy and computed tomography (CT) of the paranasal sinuses and supported by histopathological analysis. In the first patient, the excised polyp had the histological characteristic of an angiomatous antrochoanal polyp. Because of their unusual dimension, the combined transoral and endonasal endoscopic approach was performed for complete polyp excision. We discussed the clinical, histopathological and immunohistochemical characteristics of choanal polyps in comparison to inflammatory nasal polyps, and the applicable surgical techniques for treatment of these polyps. Key words: Antrochoanal polyp; Diagnosis; Chronic rhinosinusitis with nasal polyps; Endoscopic sinus surgery Introduction Case 1 Inflammatory nasal polyps are in most cases bilateral and they originate usually from anterior or posterior ethmoidal cells, and, less commonly, from maxillary sinus mucosa. In contrary, choanal polyps originate mostly from the maxillary antrum and, rarely, from the sphenoid sinus. Antrochoanal polyps originate from the inner wall of the maxillary sinus and during their growth rarely pass through the natural sinus ostia. Usually, antrochoanal polyps cause a pressure-induced destruction of the medial maxillary sinus wall and formation of an accessory ostium (1). Killian was the first to describe this disease in detail in 1906 (2). Stammberger found that antrochoanal polyps left the sinus through an accessory ostium in 70% of the cases (3). Clinical manifestations usually start with unilateral nasal obstruction, although there are reports of cases starting with epistaxis, purulent discharge, polyp strangulation, spontaneous amputation, dyspnoea and dysphagia, obstructive sleep apnoea and rhinophonia (1). Antrochoanal polyps are the most common type of choanal polyps. Other sites of origin may be the sphenoid, ethmoid, (rarely) septum, and inferior turbinate (4, 5). These polyps represent 4–6% of all nasal polyps. However, in children the number can rise up to 33% (6, 7). They are often unilateral but may be bilateral on rare occasions (8). In this report, we present two cases of unusually giant antrochoanal polyps. A 15-year-old boy was seen at the Department of Otorhinolaryngology with a ten month history of sensation of a foreign body in the throat. Other complaints were right-sided nasal obstruction and intermittent epistaxis, post-nasal discharge, slight headaches and snoring. The patient reported having previously been healthy. Examination by pharyngoscopy revealed a huge polypoid mass hanging from the nasopharynx into the mesopharynx. Upon examination with a nasal speculum, a whitish soft-tissue mass was seen in the right nasal cavity and, upon palpation with a suction tube, the mass was found to be mobile. Nasal endoscopy revealed that the mass arose from the right middle meatus and extended into the nasal cavity and therefore into the nasopharynx, hanging to medial parts of the oropharynx. Coronal and axial computed tomography (CT) images demonstrated an almost complete opacification of the right maxillary sinus and the presence of a soft-tissue mass passing through an accessory ostium into the posterior part of the nasal cavity and choana (Figure 1 a, b, c). The patient was taken to the operating theatre under general anaesthesia. On endoscopy, it was confirmed that the mass had originated in the right maxillary sinus. Before removing the intranasal mass, the tip of the inferior portion was grasped with forceps. After separating the intranasal component of the mass, the nasopharyngeal portion was 78 ACTA MEDICA (Hradec Králové) 2014; 57(2):78–82 http://dx.doi.org/10.14712/18059694.2014.44 Fig. 1: Coronal (a) and axial (b) CT of the paranasal sinuses showed an almost complete opacification of the right maxillary sinus and the presence of a soft-tissue mass passing through an accessory ostium into the posterior nasal cavity and choana, and, therefore, filling the nasopharynx (c) removed via the oral cavity by pulling the silk. This was followed by profuse bleeding, which was controlled by anterior nasal packing. The excised mass was about 12 cm in length, and with diameter of about 10 mm (Figure 2). After we removed the nasal pack, the bleeding was significantly decreased. Attention was again focused on the right nasal cavity. The uncinate process was removed and the natural maxillary sinus opening was enlarged with a backbiter. The antrum was found to be filled with the soft-tissue mass, which was of cystic appearance. The antral part was removed with cup forceps. The origin of the polyp was determined to be the posteroinferior antral wall. It was clearly separated from the accessory ostium from which the polyp leaked. Postoperatively, a nasal pack consisting of cotton gauze with antibiotic ointment was removed on the fourth day and the patient was discharged from hospital on the same day. The patient’s recovery was satisfactory and he experienced complete relief of his nasal and oral airway obstruction. Histological analysis (Figure 3) supported the diagnosis of antrochoanal polyp. In the nasal part, the polyp was covered by ciliated pseudostratified respiratory epithelium with neutrophil infiltration (a), with periodical areas of metaplastic non-ciliated cuboid epithelium (b). In the nasopharyngeal part, we found the metaplasia of the respiratory epithelium in stratified epithelium of the transitional type (c). We also could see a small number of goblet cells and a paucity of submucous glands. The basement membrane was variably thickened. The bulk of the lesion was represented by edematous subepithelial stroma with a variable degree of inflammation and fibrosis, and with the presence of large blood vessels (d). The inflammatory infiltrate was composed of a mixture of plasma cells, macrophages, lymphocytes and neutrophils (Figure 3). The patient remained asymptomatic and disease-free at follow-up 8 months later. Case 2 Fig. 2: The excised polyp mass of patient 1. The second patient, a 38-year-old man, who was previously operated on twice for nasal polyps, complained of bilateral nasal obstruction, purulent rhinorea, rinolalia and obstructiv (...truncated)