Diagnostically challenging epithelial odontogenic tumors: a selective review of 7 jawbone lesions

Abstract

Considerable variation in the clinicopathologic presentation of epithelial odontogenic tumors can sometimes be confusing and increase the chance of misdiagnosis. Seven diagnostically challenging jawbone lesions are described. There were 2 cases of mistaken identity in our ameloblastoma file. One unicystic type, initially diagnosed and treated as a lateral periodontal cyst, showed destructive recurrence 6 years postoperatively. The other globulomaxillary lesion was managed under the erroneous diagnosis of adenomatoid odontogenic tumor and recurred 4 times over an 11-year period. This tumor was found in retrospect to be consistent with an adenoid ameloblastoma with dentinoid. The diagnosis of cystic squamous odontogenic tumor (SOT) occurring as a radicular lesion of an impacted lower third molar was one of exclusion. Of two unsuspected keratocystic odontogenic tumors, one depicted deceptive features of pericoronitis, while the other case has long been in our files with the diagnosis of globulomaxillary SOT. Two cases of primary intraosseous squamous cell carcinoma appeared benign clinically and exhibited unexpected findings; an impacted third molar began to erupt in association with the growth of carcinoma and another periradicular carcinoma showed dentinoid formation. Cases selectively reviewed in this article present challenging problems which require clinical and radiographic correlation to avoid potential diagnostic pitfalls.

Keywords: Clinicopathologic correlation; Diagnostic pitfall; Epithelial odontogenic tumor; Jawbone.

Fig. 1

Unicystic ameloblastoma. a Periapical radiograph at time of first surgery, b and c six-year postoperative periapical radiographs, d primary cyst lined with thin, non-keratinizing squamous epithelium, e ameloblastoma lining of recurrent cyst (Hematoxylin–Eosin—d ×400, e ×200), f calretinin expression (ABC method, ×200)

Fig. 2

Adenoid ameloblastoma with dentinoid. a Periapical radiograph taken in 1988, b primary tumor (1988) showing adenoid spaces and dentinoid, c periapical radiograph (2nd recurrence) taken in 1995, d periapical radiograph (3rd recurrence) taken in 1998, e fourth recurrent (1999) tumor. Asterisk (*) showing sinus cavity, f typical feature of adenoid ameloblastoma with dentinoid (Hematoxylin–Eosin—b ×400, e and f ×100)

Fig. 3

Cystic squamous odontogenic tumor. a Panoramic radiograph, b and c solid-cystic proliferation of mature squamous epithelium (Hematoxylin–Eosin, ×40)

Fig. 4

Keratocystic odontogenic tumor. a Panoramic radiograph, b non-descript cyst lining with elongated rete pegs, c typical feature of keratocystic odontogenic tumor (Hematoxylin–Eosin—b ×100, c ×200)

Fig. 5

Keratocystic odontogenic tumor. a Periapical radiograph, b solid islands of bland squamous epithelium, c basal cell budding (Hematoxylin–Eosin—b ×100, c ×200), d Bcl-2 expression (ABC method, ×200)

Fig. 6

Primary intraosseous squamous cell carcinoma. a Panoramic radiograph taken in 2006, b panoramic radiograph (2008) showing eruptive movement of third molar with osteolytic change, c well-differentiated squamous cell carcinoma (Hematoxylin–Eosin, ×200), d p53 overexpression (ABC method, ×200)

Fig. 7

Primary intraosseous squamous cell carcinoma. a Periapical radiograph, b basaloid tumor occupying cancellous space, c fusion of carcinoma with gingival epithelium. Note focal duct-like structures, d clear cell population, e dentinoid deposition (Hematoxylin–Eosin—b and c ×100, d ×400, e ×200)