Case Report DOI: 10.18231/2455-6750.2017.0015 International Journal of Maxillofacial Imaging, April-June, 2017;3(2):68-70 68 Large Keratocystic Odontogenic Tumor involving entire maxillary sinus: A common pathology in uncommon location Sanika Kulkarni 1,* , Kumar Nilesh 2 , Pankaj Patil 3 , MI Parkar 4 , Kamla KA 5 1 PG Student, 2 Reader, 3 Senior Lecturer, 4 Professor & HOD, 5 Associate Professor, Dept. of Oral & Maxillofacial Surgery, School of Dental Sciences, KIMSDU *Corresponding Author: Email: ksanikag@gmail.com Abstract Keratocystic odontogenic tumor (KOT) is an odontogenic neoplasm of jaw which occurs more frequently in mandible. Its occurrence in maxilla is relatively infrequent. This article reports a case of large KOT of left maxilla involving the entire maxillary sinus extending up to the infra-orbital rim, in a middle aged person. The pathology was treated with surgical enucleation and chemical cauterization. Taking into the consideration the high recurrence rate of KOT, regular and periodic follow up is necessary in such cases. At 2 years follow up the present case showed normal healing with no recurrence. Keywords: Odontogenic keratocyst, Jaw, Tumor, Maxillary Sinus Introduction Keratocystic Odontogenic Tumor (KOT) was previously known as Odontogenic Keratocyst. (1) It is a benign but locally aggressive pathology of odontogenic origin. In 2005, the World Health Organization renamed the lesion based on its clinical, histological and immunochemical parameters and classified it as tumor. (2) KCOT presents as unicystic or multicystic intraosseous lesion. It mostly occurs in 2 nd or 3 rd decade of life and is commonly seen in mandibular ramus region. (2) KCOT differ from other odontogenic cysts in that they have biologically aggressive behaviour because of high proliferative activity of the lining epithelium, a tendency to expand in bony cancellous spaces and considerable high rate of recurrence. KCOT has created controversies with regards to its true nature. It has clinicopathological features of both simple cyst and benign neoplasm. (3) Generally, KCOT of maxilla do not present any characteristic features. Though these lesions grow and reach large size, they are many times asymptomatic. The most common clinical presentation of the tumor is a localized asymptomatic swelling. There might be presence of pain and spontaneous drainage into the oral cavity in cases of infected cyst. Mobility and displacement of teeth can be noticed in aggressive lesions. Radiographically, they appears as unilocular or multilocular radiolucency with smooth and usually sclerotic margins. (5) This article reports a case of KCOT involving entire hemi-maxilla and left maxillary sinus, extending up to the infraorbital region. Case Report A 42 years old male patient reported to Department of Oral and Maxillofacial Surgery with a complaint of painless swelling over the left side of face since past 2 months. There was mild facial asymmetry with diffuse swelling over left side of midface region. The swelling extended from below the lower eyelid region to ala- tragus line superoinferiorly and from malar prominence to the lateral part of nose mediolaterally (Fig. 1a). The swelling was non-tender and the overlying skin appeared normal. There was no local rise in temperature. Intraoral examination showed obliteration of buccal vestibule starting from 23 region to 28 region (Fig. 1b) All the associated teeth were non carious and vital with grade 1 mobility noticed with 25, 26, 27, 28. Based on these clinical features the provisional diagnosis made was cyst of maxillary sinus. Orthopantomogram showed diffuse radiolucency in left maxillary sinus (Fig. 2a). The paranasal sinus view showed haziness in the left maxillary sinus with loss of normal radiographic anatomy of maxilla (Fig. 2b). The differential diagnosis made was keratocystic odontogenic tumor, adenomatoid odontogenic tumor, ameloblastoma and central giant cell tumor. Under local anaesthesia incisional biopsy was carried out and the specimen was sent for histopathological examination. The haematoxylin and eosin stained section revealed, cystic lining showing corrugated, parakeratinized stratified squamous epithelium of 6 to 8 cell layer thick without rete ridges. The basal cell layer showed tall columnar cells with palisaded appearance, reversal polarity and nuclear hypochromatism. The underlying connective tissue revealed numerous collagen fibers, fibroblasts, sparse chronic inflammatory cell infiltrate, mainly lymphocytes. Odontogenic islands were also noticed at few places. Based upon these histological findings final diagnosis of keratocystic odontogenic tumor was made. Computed Tomography (CT) with three dimensional reconstruction was done to study the extent of the lesion. CT revealed intraosseous expansile lesion with loss of buccal cortical plate in the 23-25 region extending up to the left infraorbital rim.