The Ubiquity of Lipomas: Seven cases illustrating pathology of subcutaneous tumors with a presumptive diagnosis of lipoma based on physical examination
Main Article Content
Abstract
Lipomas are subcutaneous masses composed of adipocytes. They are benign neoplasias but may cause physical symptoms to a patient based on size or compression of adjacent tissues. They are commonly encountered by veterinary practitioners, especially in older canine patients. In general, lipomas are lenticular or ovoid in shape, soft to firm in consistency, have a smooth exterior, are encapsulated, and are freely movable. Usually, veterinary practitioners make a diagnosis of lipoma based on physical palpation or cytologic analysis of fine needle aspirates. However, many subcutaneous masses may mimic a lipoma in terms of physical appearance. Fine needle aspirates may lead to misidentification of lesions, especially if patient restraint is problematic, the tumor is small or difficult to localize, or cells of the targeted neoplasia do not exfoliate well. This paper examines seven cases whereby lipomas caused pathology themselves or were misidentified due to inaccurate diagnostic protocol. The author recommends small punch biopsy to obtain more definitive diagnosis.
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How to Cite
MORGAN, Lee W..
The Ubiquity of Lipomas: Seven cases illustrating pathology of subcutaneous tumors with a presumptive diagnosis of lipoma based on physical examination.
Medical Research Archives, [S.l.], v. 13, n. 2, feb. 2025.
ISSN 2375-1924.
Available at: <https://esmed.org/MRA/mra/article/view/6285>. Date accessed: 16 mar. 2025.
doi: https://doi.org/10.18103/mra.v13i2.6285.
Section
Research Articles
The Medical Research Archives grants authors the right to publish and reproduce the unrevised contribution in whole or in part at any time and in any form for any scholarly non-commercial purpose with the condition that all publications of the contribution include a full citation to the journal as published by the Medical Research Archives.
References
1. Vail DM, Withrow SJ. 2007. Tumors of the Skin and subcutaneous tissues. Pgs 375-401. In: Small animal clinical oncology. Withrow SJ, Vail DM (eds). Saunders/Elsevier Publ. St Louis, MO. 846p.
2. Morrison WB. 1998. Cancer in dogs and cats: medical and surgical management. Lippincott Williams and Wilkins Publ., Phil, PA. 795p.
3. Reiman N, Nolte I, Bonk U et al. 1999. Cytogenetic investigation of canine lipomas. Cancer Genet Cytogenet 111: 172-174.
4. McChesney AE, Stephens LC, Lebel J, Snyder S, Ferguson HR. 1980. Infiltrative lipoma in dogs. Vet. Pathol. 17: 316–322.
5. McEntee MC, Thrall DE. 2001. Computed tomographic imaging of infiltrative lipoma in 22 dogs. Vet. Radiol. Ultrasound 42: 221–225.
6. Bergman PJ, Withrow SJ, Straw RC, et al. 1994. Infiltrative lipoma in dogs 16 cases (1981-1992). J Am Vet Med Assoc 205:322-324.
7. McEntee MC, Page RL, Mauldin GN, Thrall DE. 2000. Results of irradiation of infiltrative lipoma in 13 dogs. Vet. Radiol. Ultrasound 41: 554–556.
8. Morgan, LW, Toal R, Siemering G, Gavin, P. 2007. Imaging diagnosis--infiltrative lipoma causing spinal cord compression in a dog. Vet Radiol Ultrasound 48:35–37.
9. Kim HJ, Chang HS, Choi CB, Song YS, Kim SM, Lee JS, Kim HY. 2005. Infiltrative lipoma in cervical bones in a dog. J. Vet. Med. Sci. 67: 1043–1046.
10. Agut A, Anson A, Navarro A., Murciano J, Soler M, Belda E, Pallares FJ, Laredo FG. 2013. Imaging diagnosis-infiltrative lipoma causing spinal cord and lumbar nerve root compression in a dog. Vet Radiol Ultrasound 54:381–383.
11. Hobert MK, Brauer C, Dziallas P, Gerhauser I, Algermissen D, Tipold A, Stein VM. 2013. Infiltrative lipoma compressing the spinal cord in 2 large-breed dogs. Can Vet J 54: 74–78.
12. Strafuss AC, Smith JE, Kennedy GA, Dennis SM. 1973. Lipomas in dogs. J Am Anim Hosp Assoc 9: 555–561.
13. Baez JL, Hendrick MJ, Shofer FS et al. 2004. Liposarcomas in dogs: 56 cases (1989-2000). J Am Vet Med Assoc. 224:887-891.
14. Doster AR, Tomlinson MJ, Mahaffey EA. 1986. Canine liposarcoma. Vet Pathol 23:84-87.,
15. McCarthy PE, Hedlund CS, Veazy RS, et al. 1996. Liposarcoma associated with a glass foreign body in a dog. J Am Vet Med Assoc 209:612-614.
16. Goldschmidt MH, Shofer FS. 1992. Skin tumors of the dog and cat. Pergamon Press, Oxford, UK. 328p.
17. Chang HR, Hajdu SI, Collin C et al. 1989. The prognostic value of histologic subtypes in primary extremity liposarcomas. Cancer 64:1514-1520.
18. Brodley RS, Kelly DF. 1968. Thyroid neoplasms in the dog. A clinicopathologic study of fifty-seven cases. Cancer 22:406-416.
19. Bailey DB, Page RL. 2007. Tumors of the endocrine system. Pg 583-609. In: Small animal clinical oncology. Withrow SJ, Vail DM (eds). Saunders/Elsevier Publ. St Louis, MO. 846p.
20. Barber LG. Thyroid tumors in dogs and cats. 2007. Vet Clin North Am Small Anim Pract 37:755-773.
21. Godwin MC. 1936. The early development of the thyroid gland in the dog with special reference to the origin and position of accessory thyroid tissue within the thoracic cavity. Anat Rec 66:233-251.
22. Broome MR, Peterson ME, Walker JR. 2014. Clinical features and treatment outcomes of 41 dogs with sublingual ectopic thyroid neoplasia. J Vet Intern Med 28:1560-1568.
23. Kang MH, Kim DY, Park HM. 2012. Ectopic thyroid carcinoma infiltrating the right atrium of the heart in a dog. Can Vet J 53:177-181.
24. Ware WA, Hopper DL. 1999. Cardiac tumors in dogs :1982-1995. J Vet Intern Med 13:95-103.
25. Stephens LC, Saunders WJ, Jaenke RS. 1982. Ectopic thyroid carcinoma with metastases in a beagle dog. Vet Pathol 19:669-675.
26. Slensky KA, Volk SW, Schwartz T et al: 2003. Acute severe hemorrhage secondary to arterial invasion in a dog with thyroid carcinoma. J Am Vet Med Assoc 223:649.
27. Marks SL, Koblik PD, Hernof WJ et al. 1994. 99mTc-Pertechnetate imaging of thyroid tumors in dogs: 29 cases (1980-1992), J Am Vet Med Assoc 204:756-760.
28. Morgan LW, Ranck RS. 2021. Pathology in practice: Ectopic thyroid carcinoma in the neck of a dog. J Am Vet Med Assoc 258:157-164
29. Raskin RE, Meyer DJ. 2001. Atlas of canine and feline cytology. WB Saunders Publ. Phil, PA. 430p.
30. Thrall DE, Gillette EL. 1995. Soft-tissue sarcomas. Semin Vet Med Surg Small Anim 10:173-179.
31. Huntz CA, Dernell WS, Powers et al. 1997. Prognostic factors for surgical treatment of soft tissue sarcomas in dogs. 75 cases (1986-1996). J Am Vet Med Assoc 21:1147-1151.
32. Meuten DJ. 2017. Tumors in domestic animals. Pg 145-147. 5th Ed. Wiley/Blackwell. 1008p.
33. Davidson EB et al. 1997. Surgical excision of soft tissue fibrosarcomas in cats. Vet Surgery 26:265-269.
34. Bowles CA, Kerber WT, Rangan SR, et al. 1972. Characterization of a transplantable, canine immature mast cell tumor. Cancer Res 32:1434-1441.
35. Thamm DH, Vial DM. 2007. Mast cell tumors. Pg 402-424. In: Small animal clinical oncology. Withrow SJ, Vail DM (eds). Saunders/Elsevier Publ. St. Louis, MO. 846p.
36. Miller WH, Griffin CE, Campbell KL. 2013. Neoplastic and non-neoplastic tumors. Pg 774-843. In: Muller and Kirk’s Small Animal Dermatology. Elsevier/Mosby Publ. St. Louis, MO. 938p.
37. Jones CL, Grahn RA, Chien MB, et al. 2004. Detection of c-kit mutations in canine mast cell tumors using fluorescent polyacrylamide gel electrophoresis. J Vet Diagn Invest 16:95-100.
38. London CA, Galli SJ, Yuuki T et al. 1999. Spontaneous canine mast cell tumors express tandem duplications in the proto-oncogene c-kit. Exp Hematol 27:689-697.
39. Patnaik AK, Ehler WJ, MacEwen EG. 1984. Canine cutaneous mast cell tumor: morphologic grading and survival time in 83 dogs. Vet Pathol 21:469-474.
40. Simpson AM, Ludwig LL, Newman SJ, et al. 2004. Evaluation of surgical margins required for complete excision of cutaneous mast cell tumors. J Am Vet Med Assoc 224:236-240.
41. Al-Sarraf R, Mauldin GN, Patniak AK et al. 1996. A prospective study of radiation therapy for the treatment of grade 2 mast cell tumors in 32 dogs. J Vet Intern Med 10:376-378.
42. Kry KL, Boston SE. 2014. Additional local therapy with primary re-excision or radiation therapy improves survival and local control after incomplete or close surgical excision of mast cell tumors in dogs. Vet Surg 43:182-189.
43. Davies DR, Wyatt KM, Jardine JE, Robertson ID, Irwin P. 2004. Vinblastine and prednisone as adjunctive therapy for cutaneous canine mast cell tumors. J Am Anim Hosp Assoc 40:124-130.
44. Macedo TR, de Quiroz GF, Casagrande TAC, et al. 2022. Imatinib mesylate for treatment of canine mast cell tumors: assessment of the response and adverse events in comparison with the conventional therapy with vinblastine and prednisone. Cells. 11:571
45. Coehlo YNB, Soldi LR, da Silva PHR et al. 2023. Tyrosine kinase inhibitors as an alternative treatment in canine mast cell tumor. Front. Vet Sci. 10:1188795.
46. De Biase D, De Leo M, Piegari G, et al. Investigation of the therapeutic role of kit expression for the treatment of canine mast cell tumors with tyrosine kinase inhibitors. Vet Sci 11:492.
47. McChesney AE, Stephens LC, Lebel J, et al. (1980). Infiltrative lipomas in dogs. Vet Pathol 17:316-322.
48. McEntee MC, Thrall DE. (2001. Computed tomographic imaging of infiltrative lipoma in 22 days. Vet Radiol Ultrasound 42:221-225.
49. Harari J, Patterson JS, Rosenthal RC. (1986). Clinical and pathological features of thyroid tumors in dogs. J Am Vet Med Assoc 188:1160.
50. Hendrick MJ, Goldschmidt MH. 1991. Do injection site reactions induce fibrosarcomas in cats? J Am Vet Med Assoc 199:968.
2. Morrison WB. 1998. Cancer in dogs and cats: medical and surgical management. Lippincott Williams and Wilkins Publ., Phil, PA. 795p.
3. Reiman N, Nolte I, Bonk U et al. 1999. Cytogenetic investigation of canine lipomas. Cancer Genet Cytogenet 111: 172-174.
4. McChesney AE, Stephens LC, Lebel J, Snyder S, Ferguson HR. 1980. Infiltrative lipoma in dogs. Vet. Pathol. 17: 316–322.
5. McEntee MC, Thrall DE. 2001. Computed tomographic imaging of infiltrative lipoma in 22 dogs. Vet. Radiol. Ultrasound 42: 221–225.
6. Bergman PJ, Withrow SJ, Straw RC, et al. 1994. Infiltrative lipoma in dogs 16 cases (1981-1992). J Am Vet Med Assoc 205:322-324.
7. McEntee MC, Page RL, Mauldin GN, Thrall DE. 2000. Results of irradiation of infiltrative lipoma in 13 dogs. Vet. Radiol. Ultrasound 41: 554–556.
8. Morgan, LW, Toal R, Siemering G, Gavin, P. 2007. Imaging diagnosis--infiltrative lipoma causing spinal cord compression in a dog. Vet Radiol Ultrasound 48:35–37.
9. Kim HJ, Chang HS, Choi CB, Song YS, Kim SM, Lee JS, Kim HY. 2005. Infiltrative lipoma in cervical bones in a dog. J. Vet. Med. Sci. 67: 1043–1046.
10. Agut A, Anson A, Navarro A., Murciano J, Soler M, Belda E, Pallares FJ, Laredo FG. 2013. Imaging diagnosis-infiltrative lipoma causing spinal cord and lumbar nerve root compression in a dog. Vet Radiol Ultrasound 54:381–383.
11. Hobert MK, Brauer C, Dziallas P, Gerhauser I, Algermissen D, Tipold A, Stein VM. 2013. Infiltrative lipoma compressing the spinal cord in 2 large-breed dogs. Can Vet J 54: 74–78.
12. Strafuss AC, Smith JE, Kennedy GA, Dennis SM. 1973. Lipomas in dogs. J Am Anim Hosp Assoc 9: 555–561.
13. Baez JL, Hendrick MJ, Shofer FS et al. 2004. Liposarcomas in dogs: 56 cases (1989-2000). J Am Vet Med Assoc. 224:887-891.
14. Doster AR, Tomlinson MJ, Mahaffey EA. 1986. Canine liposarcoma. Vet Pathol 23:84-87.,
15. McCarthy PE, Hedlund CS, Veazy RS, et al. 1996. Liposarcoma associated with a glass foreign body in a dog. J Am Vet Med Assoc 209:612-614.
16. Goldschmidt MH, Shofer FS. 1992. Skin tumors of the dog and cat. Pergamon Press, Oxford, UK. 328p.
17. Chang HR, Hajdu SI, Collin C et al. 1989. The prognostic value of histologic subtypes in primary extremity liposarcomas. Cancer 64:1514-1520.
18. Brodley RS, Kelly DF. 1968. Thyroid neoplasms in the dog. A clinicopathologic study of fifty-seven cases. Cancer 22:406-416.
19. Bailey DB, Page RL. 2007. Tumors of the endocrine system. Pg 583-609. In: Small animal clinical oncology. Withrow SJ, Vail DM (eds). Saunders/Elsevier Publ. St Louis, MO. 846p.
20. Barber LG. Thyroid tumors in dogs and cats. 2007. Vet Clin North Am Small Anim Pract 37:755-773.
21. Godwin MC. 1936. The early development of the thyroid gland in the dog with special reference to the origin and position of accessory thyroid tissue within the thoracic cavity. Anat Rec 66:233-251.
22. Broome MR, Peterson ME, Walker JR. 2014. Clinical features and treatment outcomes of 41 dogs with sublingual ectopic thyroid neoplasia. J Vet Intern Med 28:1560-1568.
23. Kang MH, Kim DY, Park HM. 2012. Ectopic thyroid carcinoma infiltrating the right atrium of the heart in a dog. Can Vet J 53:177-181.
24. Ware WA, Hopper DL. 1999. Cardiac tumors in dogs :1982-1995. J Vet Intern Med 13:95-103.
25. Stephens LC, Saunders WJ, Jaenke RS. 1982. Ectopic thyroid carcinoma with metastases in a beagle dog. Vet Pathol 19:669-675.
26. Slensky KA, Volk SW, Schwartz T et al: 2003. Acute severe hemorrhage secondary to arterial invasion in a dog with thyroid carcinoma. J Am Vet Med Assoc 223:649.
27. Marks SL, Koblik PD, Hernof WJ et al. 1994. 99mTc-Pertechnetate imaging of thyroid tumors in dogs: 29 cases (1980-1992), J Am Vet Med Assoc 204:756-760.
28. Morgan LW, Ranck RS. 2021. Pathology in practice: Ectopic thyroid carcinoma in the neck of a dog. J Am Vet Med Assoc 258:157-164
29. Raskin RE, Meyer DJ. 2001. Atlas of canine and feline cytology. WB Saunders Publ. Phil, PA. 430p.
30. Thrall DE, Gillette EL. 1995. Soft-tissue sarcomas. Semin Vet Med Surg Small Anim 10:173-179.
31. Huntz CA, Dernell WS, Powers et al. 1997. Prognostic factors for surgical treatment of soft tissue sarcomas in dogs. 75 cases (1986-1996). J Am Vet Med Assoc 21:1147-1151.
32. Meuten DJ. 2017. Tumors in domestic animals. Pg 145-147. 5th Ed. Wiley/Blackwell. 1008p.
33. Davidson EB et al. 1997. Surgical excision of soft tissue fibrosarcomas in cats. Vet Surgery 26:265-269.
34. Bowles CA, Kerber WT, Rangan SR, et al. 1972. Characterization of a transplantable, canine immature mast cell tumor. Cancer Res 32:1434-1441.
35. Thamm DH, Vial DM. 2007. Mast cell tumors. Pg 402-424. In: Small animal clinical oncology. Withrow SJ, Vail DM (eds). Saunders/Elsevier Publ. St. Louis, MO. 846p.
36. Miller WH, Griffin CE, Campbell KL. 2013. Neoplastic and non-neoplastic tumors. Pg 774-843. In: Muller and Kirk’s Small Animal Dermatology. Elsevier/Mosby Publ. St. Louis, MO. 938p.
37. Jones CL, Grahn RA, Chien MB, et al. 2004. Detection of c-kit mutations in canine mast cell tumors using fluorescent polyacrylamide gel electrophoresis. J Vet Diagn Invest 16:95-100.
38. London CA, Galli SJ, Yuuki T et al. 1999. Spontaneous canine mast cell tumors express tandem duplications in the proto-oncogene c-kit. Exp Hematol 27:689-697.
39. Patnaik AK, Ehler WJ, MacEwen EG. 1984. Canine cutaneous mast cell tumor: morphologic grading and survival time in 83 dogs. Vet Pathol 21:469-474.
40. Simpson AM, Ludwig LL, Newman SJ, et al. 2004. Evaluation of surgical margins required for complete excision of cutaneous mast cell tumors. J Am Vet Med Assoc 224:236-240.
41. Al-Sarraf R, Mauldin GN, Patniak AK et al. 1996. A prospective study of radiation therapy for the treatment of grade 2 mast cell tumors in 32 dogs. J Vet Intern Med 10:376-378.
42. Kry KL, Boston SE. 2014. Additional local therapy with primary re-excision or radiation therapy improves survival and local control after incomplete or close surgical excision of mast cell tumors in dogs. Vet Surg 43:182-189.
43. Davies DR, Wyatt KM, Jardine JE, Robertson ID, Irwin P. 2004. Vinblastine and prednisone as adjunctive therapy for cutaneous canine mast cell tumors. J Am Anim Hosp Assoc 40:124-130.
44. Macedo TR, de Quiroz GF, Casagrande TAC, et al. 2022. Imatinib mesylate for treatment of canine mast cell tumors: assessment of the response and adverse events in comparison with the conventional therapy with vinblastine and prednisone. Cells. 11:571
45. Coehlo YNB, Soldi LR, da Silva PHR et al. 2023. Tyrosine kinase inhibitors as an alternative treatment in canine mast cell tumor. Front. Vet Sci. 10:1188795.
46. De Biase D, De Leo M, Piegari G, et al. Investigation of the therapeutic role of kit expression for the treatment of canine mast cell tumors with tyrosine kinase inhibitors. Vet Sci 11:492.
47. McChesney AE, Stephens LC, Lebel J, et al. (1980). Infiltrative lipomas in dogs. Vet Pathol 17:316-322.
48. McEntee MC, Thrall DE. (2001. Computed tomographic imaging of infiltrative lipoma in 22 days. Vet Radiol Ultrasound 42:221-225.
49. Harari J, Patterson JS, Rosenthal RC. (1986). Clinical and pathological features of thyroid tumors in dogs. J Am Vet Med Assoc 188:1160.
50. Hendrick MJ, Goldschmidt MH. 1991. Do injection site reactions induce fibrosarcomas in cats? J Am Vet Med Assoc 199:968.