Benign cementoblastoma (true cementoma) in a cat

Abstract

Case summary: A 10-year-old castrated male domestic shorthair cat was presented for assessment of a gingival mass surrounding the left maxillary third and fourth premolar teeth. The mass was surgically removed by means of a marginal rim excision, and the tissue was submitted for histological assessment. It was identified as a benign cementoblastoma (true cementoma). There was proliferation of mineralized eosinophilic material with multiple irregularly placed lacunae and reversal lines, reminiscent of cementum. The cat recovered uneventfully from the anesthesia, and there was no evidence of tumor recurrence 6 months after surgery.

Relevance and novel information: Cementoblastomas (true cementomas) in domestic animals are rare, with just a few reports in ruminants, monogastric herbivores and rodents. Cementoblastoma is considered a benign tumor that arises from the tooth root. The slow, expansive and constant growth that characterizes these masses may be accompanied by signs of oral discomfort and dysphagia. This case report is intended to increase knowledge regarding this tumor in cats and also highlights the importance of complete excision of the neoplasm. To our knowledge, there are no previous reports in the literature of cementoblastoma in the cat.

Figure 1

(a) A 10-year-old domestic shorthair cat presented with an erythematous, firm ulcerated gingival mass on the buccal aspect of the left maxillary third and fourth premolar teeth (teeth 207 and 208). (b) The corresponding intraoral dental radiograph showed a well circumscribed, radiopaque mass (arrow) affecting the interproximal region between teeth 207 and 208; some tooth resorption and loss of the periodontal ligament space (arrowheads) are evident around the mesiobuccal root of tooth 208

Figure 2

(a) Buccal and (b) ventral views to the left maxillary area in a 10-year-old domestic shorthair cat. A surgical marker pen was used to outline the planned incisions. (c) Intraoperative view of the affected area after excision of the mass. (d) Closure buccal flap was sutured over the wound, using an absorbable monofilament in a simple interrupted pattern. (e) A postoperative intraoral radiograph was obtained, showing the affected area after rim excision (arrowheads), the left maxillary second premolar (arrow) and the zygomatic arch (asterisk). (f) The excised tissue was submitted for histopathological assessment. The asterisks show some intact roots of the third and fourth premolar teeth. Remaining root tips were extracted following excision of the mass. Because this was a clean-contaminated procedure, no surgical drapes were used. However, aseptic technique, including disposable synthetic or reusable cloth drapes may be used to minimize contamination^,

Figure 3

(a) Photomicrograph of the submitted specimen showing proliferation of mineralized eosinophilic material (asterisk) that expands the gingiva (arrowheads) (×4 magnification, hematoxylin and eosin). (b) There are multiple irregularly placed lacunae (arrowheads) and reversal lines (arrow) (×20 magnification, hematoxylin and eosin). (c) The mass is focally adhered to a tooth root near the cementoenamel junction (arrowhead), contiguous with the normal cementum layer (arrow) (×4 magnification, hematoxylin and eosin)