Tubuloductal/syringoid variant of central odontogenic fibroma with amyloid?

Abstract

<h3>Introduction</h3> Glandular tumors of jaw bones present, most often, histopathologic features of salivary gland and, rarely, of cutaneous glandular neoplasms and are thought to predominantly originate from odontogenic epithelium. <h3>Materials and Methods</h3> An unusual maxillary tumor in a 74-year-old male is presented exhibiting radiolucency and root resorption in the apical area of teeth #6-7. <h3>Results</h3> Preparations revealed occasionally branching tubular cords and ductal structures characterized, mostly, by a bilayer composed of luminal Ber-EP4, cytokeratin (CK) 7 and occasionally CK8/18 positive cells and varying from cuboidal to low columnar, and abluminal, CK5/6 positive, basal/basaloid cells revealing nuclear reactivity for p63/p40. Smooth muscle actin and calponin were negative, save for a single focus for calponin, confirming absence of myoepithelial support or epithelial mesenchymal transition. CK19 exhibited staining of both layers, the luminal being more intense. Eosinophilic secretory material and, occasionally, a luminal pellicle were decorated with CK8/18 and polyclonal carcinoembryonic antigen (CEA). CD1a identified only rare Langerhans' cells and Ki67 decorated 1-2% of abluminal cell nuclei. Small solid nests of epithelial cells were also present. Infrequently, an apparent transition of a nest into a tubular structure was appreciated. The partially inflamed stroma featured multiple hyalinized acellular deposits consistent with amyloid, as confirmed by bright orange Congo red reactivity with apple-green birefringence, which reacted with antibodies against odontogenic ameloblast-associated (ODAM) protein but not amelotin and secretory calcium-binding phosphoprotein proline-glutamine rich 1. <h3>Conclusions</h3> Based on the above the diagnosis of tubuloductal/syringoid variant of central odontogenic fibroma with ODAM amyloid is favored.