• 1. Séguin B, Leibman NF, Bregazzi VS, et al. Clinical outcome of dogs with grade-II mast cell tumors treated with surgery alone: 55 cases (1996–1999). J Am Vet Med Assoc 2001; 218: 11201123.

    • Search Google Scholar
    • Export Citation
  • 2. Simpson AM, Ludwig LL, Newman SJ, et al. Evaluation of surgical margins required for complete excision of cutaneous mast cell tumors in dogs. J Am Vet Med Assoc 2004; 224: 236240.

    • Search Google Scholar
    • Export Citation
  • 3. Fulcher RP, Ludwig LL, Bergman PJ, et al. Evaluation of a two-centimeter lateral surgical margin for excision of grade I and grade II cutaneous mast cell tumors in dogs. J Am Vet Med Assoc 2006; 228: 210215.

    • Search Google Scholar
    • Export Citation
  • 4. Schultheiss PC, Gardiner DW, Rao S, et al. Association of histologic tumor characteristics and size of surgical margins with clinical outcome after surgical removal of cutaneous mast cell tumors in dogs. J Am Vet Med Assoc 2011; 238: 14641469.

    • Search Google Scholar
    • Export Citation
  • 5. Thamm DH, Vail DM. Mast cell tumors. In: Withrow SJ, Vail DM, eds. Withrow & MacEwen's small animal clinical oncology. 4th ed. St Louis: Saunders Elsevier, 2007; 402424.

    • Search Google Scholar
    • Export Citation
  • 6. Pratschke KM, Atherton MJ, Sillito JA, et al. Evaluation of a modified proportional margins approach for surgical resection of mast cell tumors in dogs: 40 cases (2008–2012). J Am Vet Med Assoc 2013; 243: 14361441.

    • Search Google Scholar
    • Export Citation
  • 7. Weisse C, Shofer FS, Sorenmo K. Recurrence rates and sites for grade II canine cutaneous mast cell tumors following complete surgical excision. J Am Anim Hosp Assoc 2002; 38: 7173.

    • Search Google Scholar
    • Export Citation
  • 8. Thompson JJ, Pearl DL, Yager JA, et al. Canine subcutaneous mast cell tumor: characterization and prognostic indices. Vet Pathol 2011; 48: 156168.

    • Search Google Scholar
    • Export Citation
  • 9. Murphy S, Sparkes AH, Smith KC, et al. Relationships between the histologic grade of cutaneous mast cell tumours in dogs, their survival and the efficacy of surgical resection. Vet Rec 2004; 154: 743746.

    • Search Google Scholar
    • Export Citation
  • 10. Blasdale C, Charlton FG, Weatherhead SC, et al. Effect of tissue shrinkage on histologic tumour-free margin after excision of basal cell carcinoma. Br J Dermatol 2010; 162: 607610.

    • Search Google Scholar
    • Export Citation
  • 11. Hudson-Peacock MJ, Matthews JN, Lawrence CM, et al. Relation between size of skin excision, wound, and specimen. J Am Acad Dermatol 1995; 32: 10101015.

    • Search Google Scholar
    • Export Citation
  • 12. Yeap BH, Muniandy S, Lee SK, et al. Specimen shrinkage and its influence on margin assessment in breast cancer. Asian J Surg 2007; 30: 183187.

    • Search Google Scholar
    • Export Citation
  • 13. Mistry RC, Qureshi SS, Kumaran C. Post-resection mucosal margin shrinkage in oral cancer: quantification and significance. J Surg Oncol 2005; 91: 131133.

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

    • Search Google Scholar
    • Export Citation
  • 15. Rutherford EE, Karanjia ND. The measurement of liver resection margins. HPB (Oxford) 2004; 6: 1820.

  • 16. Rieger J, Twardziok S, Huenigen H, et al. Porcine intestinal mast cells. Evaluation of different fixatives for histochemical staining techniques considering tissue shrinkage. Eur J Histochem 2013; 57: 133142.

    • Search Google Scholar
    • Export Citation
  • 17. Reimer SB, Séguin B, DeCock HE, et al. Evaluation of the effect of routine histologic processing on the size of skin samples obtained from dogs. Am J Vet Res 2005; 66: 500505.

    • Search Google Scholar
    • Export Citation
  • 18. Patnaik AK, Ehler WJ, MacEwen EG. Canine cutaneous mast cell tumor: morphologic grading and survival time in 83 dogs. Vet Pathol 1984; 21: 469474.

    • Search Google Scholar
    • Export Citation
  • 19. Kamstock DA, Ehrhart EJ, Getzy DM, et al. Recommended guidelines for submission, trimming, margin evaluation, and reporting of tumor biopsy specimens in veterinary surgical pathology. Vet Pathol 2011; 48: 1931.

    • Search Google Scholar
    • Export Citation
  • 20. Irwin DHG. Tension lines in the skin of the dog. J Small Anim Pract 1966; 7: 593598.

  • 21. Kiupel M, Webster JD, Bailey KL, et al. Proposal of a 2-tier histologic grading system for canine cutaneous mast cell tumors to more accurately predict biological behavior. Vet Pathol 2011; 48: 147155.

    • Search Google Scholar
    • Export Citation
  • 22. Golomb FM, Doyle JP, Grin CM, et al. Determination of pre-excision surgical margins of melanomas from fixed-tissue specimens. Plast Reconstr Surg 1991; 88: 804809.

    • Search Google Scholar
    • Export Citation
  • 23. Dauendorffer JN, Bastuji-Garin S, Guéro S, et al. Shrinkage of skin excision specimens: formalin fixation is not the culprit. Br J Dermatol 2009; 160: 810814.

    • Search Google Scholar
    • Export Citation
  • 24. Michels GM, Knapp DW, DeNicola DB, et al. Prognosis following surgical excision of canine cutaneous mast cell tumors with histopathologically tumor-free versus nontumor-free margins: a retrospective study of 31 cases. J Am Anim Hosp Assoc 2002; 38: 458466.

    • Search Google Scholar
    • Export Citation

Advertisement

Surgically planned versus histologically measured lateral tumor margins for resection of cutaneous and subcutaneous mast cell tumors in dogs: 46 cases (2010–2013)

Marije Risselada DVM, PhD1, Kyle G. Mathews DVM, MS2, and Emily Griffith PhD3,4
View More View Less
  • 1 Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27607.
  • | 2 Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27607.
  • | 3 Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27607.
  • | 4 Department of Statistics, College of Agriculture and Life Sciences, North Carolina State University, Raleigh, NC 27607.

Abstract

Objective—To compare preplanned lateral surgical margins and measured lateral histologic margins for cutaneous and subcutaneous mast cell tumor (MCT) resections in dogs.

Design—Retrospective case series.

Sample—51 biopsy specimens from dogs (n = 46) with MCTs.

Procedures—All canine patients that underwent curative-intent surgical resection of cutaneous or subcutaneous MCTs from January 1, 2010, through June 30, 2013, with complete medical records including signalment, body condition score (BCS), surgery report (with measured surgical margins), and histopathology report were included. The surgically measured tumor margins in each quadrant were grouped and compared with the corresponding histologic margins. Specimens from dogs with truncal MCTs and a BCS of 7 to 9 on a scale from 1 to 9 (ie, high) were compared with those of dogs with a BCS of 4 to 6 to evaluate effect of BCS on tissue margins.

Results—51 specimens were included. Surgically mapped lateral margins differed significantly from histologically reported margins in all 4 quadrants. The mean histologic margins were 35% to 42% smaller than the surgical margins for the combined 51 specimens. A higher BCS did not significantly influence the magnitude of the decrease in lateral margins measured histologically. No significant difference was found for the magnitude of the differences between any of the 4 lateral margins.

Conclusions and Clinical Relevance—Results of this study suggested that surgical and histologic margins may differ significantly for canine cutaneous and subcutaneous MCTs. This may be a result of tissue shrinkage following excision and fixation, extension of the MCT beyond palpable margins, or both. Histologic measurements may significantly underestimate the tumor-free margins in dogs with cutaneous and subcutaneous MCTs. (J Am Vet Med Assoc 2015;247:184–189)

Abstract

Objective—To compare preplanned lateral surgical margins and measured lateral histologic margins for cutaneous and subcutaneous mast cell tumor (MCT) resections in dogs.

Design—Retrospective case series.

Sample—51 biopsy specimens from dogs (n = 46) with MCTs.

Procedures—All canine patients that underwent curative-intent surgical resection of cutaneous or subcutaneous MCTs from January 1, 2010, through June 30, 2013, with complete medical records including signalment, body condition score (BCS), surgery report (with measured surgical margins), and histopathology report were included. The surgically measured tumor margins in each quadrant were grouped and compared with the corresponding histologic margins. Specimens from dogs with truncal MCTs and a BCS of 7 to 9 on a scale from 1 to 9 (ie, high) were compared with those of dogs with a BCS of 4 to 6 to evaluate effect of BCS on tissue margins.

Results—51 specimens were included. Surgically mapped lateral margins differed significantly from histologically reported margins in all 4 quadrants. The mean histologic margins were 35% to 42% smaller than the surgical margins for the combined 51 specimens. A higher BCS did not significantly influence the magnitude of the decrease in lateral margins measured histologically. No significant difference was found for the magnitude of the differences between any of the 4 lateral margins.

Conclusions and Clinical Relevance—Results of this study suggested that surgical and histologic margins may differ significantly for canine cutaneous and subcutaneous MCTs. This may be a result of tissue shrinkage following excision and fixation, extension of the MCT beyond palpable margins, or both. Histologic measurements may significantly underestimate the tumor-free margins in dogs with cutaneous and subcutaneous MCTs. (J Am Vet Med Assoc 2015;247:184–189)

Contributor Notes

Address correspondence to Dr. Risselada (marije_risselada@ncsu.edu).