1
|
Feigin K, Bell C. Desmoplastic histological subtype of ameloblastoma in 16 dogs. Front Vet Sci 2024; 11:1362237. [PMID: 38638641 PMCID: PMC11024383 DOI: 10.3389/fvets.2024.1362237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Accepted: 03/11/2024] [Indexed: 04/20/2024] Open
Abstract
Ameloblastoma in dogs most often has a highly conserved acanthomatous cell morphology and is recognized as canine acanthomatous ameloblastoma (CAA) while conventional ameloblastoma (CA) makes up a smaller yet morphologically diverse group of epithelial odontogenic tumors. In humans, a rare desmoplastic histological subtype has distinctive clinical, radiological, and microscopic features. Desmoplastic ameloblastoma (DA) has not previously been described in dogs, although it has been rarely referenced in the veterinary literature. This is the first thorough description of a case series of DA in dogs and describes clinical presentation, diagnostic imaging findings, histopathological features for diagnosis, and treatment outcome. Clinically, DA most often presents as a mass or swelling in the rostral mandible or maxilla of middle age to older dogs. On diagnostic imaging, the lesion has a radiolucent or mixed pattern with well-defined borders and variable loculation. As a solid, fibrous tumor with obscured odontogenic epithelium, DA is challenging to diagnose histologically and can mimic several other oral tumors, both benign and malignant. As an ameloblastoma, the biological behavior of DA is locally destructive yet benign and prognosis is favorable following surgical excision.
Collapse
Affiliation(s)
| | - Cynthia Bell
- Specialty Oral Pathology for Animals, Geneseo, IL, United States
| |
Collapse
|
2
|
Bolek AM, Smith MM, Taney K, Powers B. Symphyseal-Sparing Mandibulectomy for Canine Acanthomatous Ameloblastoma in Dogs: 35 Cases. J Vet Dent 2024; 41:10-16. [PMID: 37006121 DOI: 10.1177/08987564231163692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2023]
Abstract
Canine acanthomatous ameloblastoma (CAA) has been reported to be the most prevalent odontogenic tumor in dogs. The most common location of this tumor is the rostral mandible. Symphyseal-sparing mandibulectomy has been shown to be an effective technique to maintain mandibular continuity and promote early return to function. In this retrospective study, 35 dogs with CAA associated with a mandibular canine tooth were evaluated following a symphyseal-sparing rostral mandibulectomy. Dogs with intraoperative transection of the canine tooth root and subsequent root fragment extraction were included. The objective of this study was to evaluate outcome following excision of CAA with mid-root transection. Data retrospectively evaluated in this study included the following: narrowest tumor margin, narrowest tumor margin at the border associated with the transected canine root, tumor size, and prevalence of local recurrence. This study showed that 82.86% of CAA were completely excised with tumor-free margins (N = 29). The median narrowest overall tumor-free margin was 3.5 mm (interquartile range [IQR] 2.0-6.5 mm) and the median tumor-free margin associated with the border of the transected canine root was 5.0 mm (IQR 3.1-7.0 mm). Follow-up data was obtained in 25 cases via phone interviews with referring veterinarians and clients. No local tumor recurrence was reported in cases with incomplete tumor excision (N = 5). All dogs with follow-up data survived at least 1 year following surgery. It was concluded that segmental or rostral mandibulectomy with wide margins to include the entire mandibular canine tooth with subsequent mandibular instability may not be warranted for dogs with CAA associated with this tooth.
Collapse
Affiliation(s)
- Ann M Bolek
- Center for Veterinary Dentistry and Oral Surgery, Gaithersburg, MD, USA
| | - Mark M Smith
- Center for Veterinary Dentistry and Oral Surgery, Gaithersburg, MD, USA
| | - Kendall Taney
- Center for Veterinary Dentistry and Oral Surgery, Gaithersburg, MD, USA
| | | |
Collapse
|
3
|
Tsugawa AJ, Arzi B, Vapniarsky N, Verstraete FJM. A Retrospective Study on Mandibular Reconstruction Following Excision of Canine Acanthomatous Ameloblastoma. Front Vet Sci 2022; 9:900031. [PMID: 35647098 PMCID: PMC9132539 DOI: 10.3389/fvets.2022.900031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2022] [Accepted: 04/08/2022] [Indexed: 11/15/2022] Open
Abstract
The successful excision of a locally invasive tumor such as canine acanthomatous ameloblastoma (CAA) typically results in a mandibular contour-derforming, critical-size defect that alters the jaw kinematics, and may affect the patient's quality of life. In this case series, we describe our experience using the regenerative approach of a titanium locking plate and compression resistant matrix infused with rhBMP-2 for the immediate or delayed reconstruction following mandibulectomy for the excision of mandibular CAA in 11 dogs. Surgical planning included computed tomography (CT), with and without contrast, in all cases, and 3D-printed models in four cases. Tumor-free surgical margins were achieved in all dogs. Clinical and diagnostic imaging follow-up (mean, 23.1 months) were performed in-person (11 cases) and with CT/cone-beam computed tomography in most cases, with standard radiography (3 cases) and telemedicine being utilized in 5 cases. At 2 weeks postoperatively, hard tissue was palpable at the defect. Follow-up imaging at 1 month postoperatively revealed evidence of bridging new bone with a heterogeneous appearance, that remodeled over 3–6 months to bone of a similar size, shape and trabecular pattern as native bone. Histological evaluation of regenerated bone was available in two cases, and was supportive of our clinical and imaging findings of normal remodeled bone. Clinically, all dogs returned to a normal lifestyle, rapidly resumed eating and drinking, and exhibited normal occlusion. Complications included wound dehiscence in one dog and self-limiting exuberant bone formation in two dogs. Tumor regrowth, failure of the implant or fracture of the regenerated bone were not observed. We conclude that the mandibular reconstruction using a regenerative approach is safe, feasible, and results in restoration of mandibular contour in dogs following segmental and bilateral rostral mandibulectomy for benign but invasive oral tumors such as CAA.
Collapse
Affiliation(s)
- Anson J. Tsugawa
- School of Veterinary Medicine, William R. Pritchard Veterinary Medical Teaching Hospital, University of California, Davis, Davis, CA, United States
| | - Boaz Arzi
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, Davis, CA, United States
- School of Veterinary Medicine, Veterinary Institute for Regenerative Cures, University of California, Davis, Davis, CA, United States
- *Correspondence: Boaz Arzi
| | - Natalia Vapniarsky
- School of Veterinary Medicine, Veterinary Institute for Regenerative Cures, University of California, Davis, Davis, CA, United States
- Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California, Davis, Davis, CA, United States
| | - Frank J. M. Verstraete
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, Davis, CA, United States
| |
Collapse
|
4
|
Goldschmidt S. Surgical Margins for Ameloblastoma in Dogs: A Review With an Emphasis on the Future. Front Vet Sci 2022; 9:830258. [PMID: 35392113 PMCID: PMC8980539 DOI: 10.3389/fvets.2022.830258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 01/18/2022] [Indexed: 11/13/2022] Open
Abstract
Ameloblastoma is a benign epithelial odontogenic tumor with the capacity to aggressively invade the surrounding bone. Surgical removal of the tumor can result in extended disease-free interval (cure). However, controversy surrounds the most appropriate surgical margin required to prevent local recurrence while simultaneously minimizing morbidity. En bloc excisional surgery carries the risk of major complications such as mandibular drift, hemorrhage, and oronasal fistula formation. Conservative therapy without a safety margin reduces potential morbidity but is likely to result in local recurrence. No reliable rate, nor time to recurrence, is documented but may be as high as 91% with conservative therapy. Conversely, surgery with a 10- to 20-mm margin is associated with a 0–4.6% recurrence rate. There is no documented difference in the recurrence rate with a 10- vs. 20-mm margin. The correlation of the histologic margin with the recurrence rate following excisional surgery has not determined a required histologic safety margin. Rather, no local recurrence occurs despite narrow or incomplete margins. Thus, pathologic margins > 0 mm may be sufficient to prevent local recurrence or recurrence may be protracted. Accordingly, a narrow (5–10 mm) gross surgical margin may be the most appropriate. Additional research is required for confirmation, and only level 4 evidence on safety margins has been achieved thus far. Future work should focus on defining the extension of neoplastic cells past the demarcation of ameloblastoma on variable diagnostic imaging modalities as well as determining the recurrence rate with various surgical and histologic safety margins.
Collapse
|