• 1. Uzal FA, Plattner BL, Hostetter JM. Alimentary system. In: Maxie G, ed. Jubb, Kennedy & Palmer's pathology of domestic animals. 6th ed. St Louis: Elsevier Health Sciences, 2015;2627.

    • Search Google Scholar
    • Export Citation
  • 2. Ramos-Vara JA, Beissenherz ME, Miller MA, et al. Retrospective study of 338 canine oral melanomas with clinical, histologic, and immunohistochemical review of 129 cases. Vet Pathol 2000;37:597608.

    • Search Google Scholar
    • Export Citation
  • 3. Modiano JF, Ritt MG, Wojcieszyn J. The molecular basis of canine melanoma: pathogenesis and trends in diagnosis and therapy. J Vet Intern Med 1999;13:163174.

    • Search Google Scholar
    • Export Citation
  • 4. Nishiya AT, Massoco CO, Felizzola CR, et al. Comparative aspects of canine melanoma. Vet Sci 2016;3:710.

  • 5. Hahn KA, DeNicola DB, Richardson RC, et al. Canine oral malignant melanoma: prognostic utility of an alternative staging system. J Small Anim Pract 1994;35:251256.

    • Search Google Scholar
    • Export Citation
  • 6. Bergman PJ. Canine oral melanoma. Clin Tech Small Anim Pract 2007;22:5560.

  • 7. Smith SH, Goldschmidt MH, McManus PM. A comparative review of melanocytic neoplasms. Vet Pathol 2002;39:651678.

  • 8. Smedley RC, Spangler WL, Esplin DG, et al. Prognostic markers for canine melanocytic neoplasms: a comparative review of the literature and goals for future investigation. Vet Pathol 2011;48:5472.

    • Search Google Scholar
    • Export Citation
  • 9. Spangler WL, Kass PH. The histologic and epidemiologic bases for prognostic considerations in canine melanocytic neoplasia. Vet Pathol 2006;43:136149.

    • Search Google Scholar
    • Export Citation
  • 10. Bergin IL, Smedley RC, Esplin DG, et al. Prognostic evaluation of Ki67 threshold value in canine oral melanoma. Vet Pathol 2011;48:4153.

    • Search Google Scholar
    • Export Citation
  • 11. Fluss R, Faraggi D, Reiser B. Estimation of the Youden index and its associated cutoff point. Biom J 2005;47:458472.

  • 12. Bergman PJ, Kent MS, Farese JP. Melanoma. In: Withrow SJ, Vail DM, Page RL, eds. Withrow and MacEwen's small animal clinical oncology. 5th ed. St Louis: Elsevier Health Sciences, 2012;321334.

    • Search Google Scholar
    • Export Citation
  • 13. Dennis MM, Ehrhart N, Duncan CG, et al. Frequency of and risk factors associated with lingual lesions in dogs: 1,196 cases (1995–2004). J Am Vet Med Assoc 2006;228:15331537.

    • Search Google Scholar
    • Export Citation
  • 14. Todoroff RJ, Brodey RS. Oral and pharyngeal neoplasia in the dog: a retrospective survey of 361 cases. J Am Vet Med Assoc 1979;175:567571.

    • Search Google Scholar
    • Export Citation
  • 15. Goldschmidt MH. Histological classification of epithelial and melanocytic tumors of the skin of domestic animals. Washington, DC: Armed Forces Institute of Pathology, 1998;331340.

    • Search Google Scholar
    • Export Citation
  • 16. Millanta F, Fratini F, Corazza M, et al. Proliferation activity in oral and cutaneous canine melanocytic tumours: correlation with histological parameters, location, and clinical behaviour. Res Vet Sci 2002;73:4551.

    • Search Google Scholar
    • Export Citation
  • 17. Behjatnia B, Sim J, Bassett LW, et al. Does size matter? Comparison study between MRI, gross, and microscopic tumor sizes in breast cancer in lumpectomy specimens. Int J Clin Exp Pathol 2010;3:303309.

    • Search Google Scholar
    • Export Citation
  • 18. Fitzgibbons PL, Page DL, Weaver D, et al. Prognostic factors in breast cancer. Arch Pathol Lab Med 2000;124:966978.

  • 19. Verma VP, Kaur N, Agarwal N, et al. Intra-operative measurement of tumour size in breast cancer and its comparison with other methods: a prospective study. Ecancermedicalscience 2008;2:96.

    • Search Google Scholar
    • Export Citation
  • 20. Johnson RE, Sigman JD, Funk GF, et al. Quantification of surgical margin shrinkage in the oral cavity. Head Neck 1997;19:281286.

  • 21. Mohiyuddin SMA, Padiyar BV, Suresh TN, et al. Clinicopathological study of surgical margins in squamous cell carcinoma of buccal mucosa. World J Otorhinolaryngol Head Neck Surg 2016;2:1721.

    • Search Google Scholar
    • Export Citation
  • 22. Siu KF, Cheung HC, Wong J. Shrinkage of the esophagus after resection for carcinoma. Ann Surg 1986;203:173176.

  • 23. Jonmarker S, Valdman A, Lindberg A, et al. Tissue shrinkage after fixation with formalin injection of prostatectomy specimens. Virchows Arch 2006;449:297301.

    • Search Google Scholar
    • Export Citation
  • 24. Tran T, Sundaram CP, Bahler CD, et al. Correcting the shrinkage effects of formalin fixation and tissue processing for renal tumors: toward standardization of pathological reporting of tumor size. J Cancer 2015;6:759766.

    • Search Google Scholar
    • Export Citation

Advertisement

Tumor size as a predictor of lymphatic invasion in oral melanomas of dogs

Kenneth A. Carroll BVSc1, Charles A. Kuntz DVM, MS2, Jane Heller BVSc, PhD3, Andrew Peters BVSc, PhD3, Randi Rotne BVSc, PhD3, and Andrew Dunn BVSc4
View More View Less
  • 1 1Department of Small Animal Medicine and Surgery, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27606.
  • | 2 2Southpaws Specialty Surgery for Animals, Moorabbin, VIC 3189, Australia.
  • | 3 3School of Animal and Veterinary Sciences, Charles Sturt University, Wagga Wagga, NSW 2650, Australia.
  • | 4 4Adelaide Veterinary Specialist and Referral Centre, Norwood, SA 5067, Australia.

Abstract

OBJECTIVE

To investigate putative associations between oral melanoma size and variables of histologic grade such as mitotic index, nuclear atypia, junctional activity, ulceration, lymphatic invasion, and degree of pigmentation.

SAMPLE

59 samples of oral melanomas from dogs sourced from 6 diagnostic laboratories within Australia.

PROCEDURES

The size of each melanoma was microscopically measured, and each sample was evaluated for variables of histologic grade including mitotic index, nuclear atypia, junctional activity, ulceration, lymphatic invasion, and degree of pigmentation by a veterinary pathologist. The association between tumor size and histologic outcomes was then statistically evaluated.

RESULTS

A significant relationship was identified between the size of oral melanomas and a single variable of histologic grade, lymphatic invasion, with larger tumors more likely to show lymphatic invasion. Further analysis revealed 2 applicable size thresholds for different clinical scenarios. Results indicated lymphatic invasion can confidently be ruled out for tumors < 6.5 mm in diameter (100% sensitivity) and ruled in for tumors ≥ 24.5 mm in diameter (100% specificity).

CONCLUSIONS AND CLINICAL RELEVANCE

An association was found for oral melanomas of dogs between tumor size and lymphatic invasion.

Abstract

OBJECTIVE

To investigate putative associations between oral melanoma size and variables of histologic grade such as mitotic index, nuclear atypia, junctional activity, ulceration, lymphatic invasion, and degree of pigmentation.

SAMPLE

59 samples of oral melanomas from dogs sourced from 6 diagnostic laboratories within Australia.

PROCEDURES

The size of each melanoma was microscopically measured, and each sample was evaluated for variables of histologic grade including mitotic index, nuclear atypia, junctional activity, ulceration, lymphatic invasion, and degree of pigmentation by a veterinary pathologist. The association between tumor size and histologic outcomes was then statistically evaluated.

RESULTS

A significant relationship was identified between the size of oral melanomas and a single variable of histologic grade, lymphatic invasion, with larger tumors more likely to show lymphatic invasion. Further analysis revealed 2 applicable size thresholds for different clinical scenarios. Results indicated lymphatic invasion can confidently be ruled out for tumors < 6.5 mm in diameter (100% sensitivity) and ruled in for tumors ≥ 24.5 mm in diameter (100% specificity).

CONCLUSIONS AND CLINICAL RELEVANCE

An association was found for oral melanomas of dogs between tumor size and lymphatic invasion.

Contributor Notes

Address correspondence to Dr. Carroll (kacarro3@ncsu.edu).