JPC SYSTEMIC PATHOLOGY
DIGESTIVE SYSTEM
September 2018
D-N12

Signalment (JPC Accession # 4035521):  8-month-old female Balb/c mouse

HISTORY:  The mouse was culled during routine surveillance.  It had a 3cm diameter, cystic, subcutaneous mass of the ventral neck and cranial chest composed of pale, friable tissue with a rich blood supply.  The mass had a central cavity containing blood and viscous material.  There were no other gross abnormalities.

HISTOPATHOLOGIC DESCRIPTION:  Haired skin:  Expanding the subcutis, elevating the overlying dermis and epidermis, and compressing atrophic pre-existing mucinous and mixed salivary glands, is a 1.25x1cm expansile, well-demarcated, partially encapsulated, moderately cellular, multilobular, multicystic neoplasm.  The neoplasm is composed of spindle cells arranged in short streams and nests divided into lobules, and often palisading along a moderate fibrovascular stroma.  Neoplastic cells have indistinct cell borders, a moderate amount of finely vacuolated basophilic cytoplasm, and oval to elongate nuclei with finely clumped chromatin and 1-2 small basophilic nuclei.  Mitoses average 1-2 per 400X high power field.  Many of the neoplastic lobules contain large central areas of lytic necrosis.  At one edge of the section, there is a large area of mature granulation tissue with a focus of the previously described neoplasm.  The neoplasm is bordered on one side by an extensive area of granulation tissue admixed with granulomatous inflammation admixed with hemorrhage and hemosiderin-laden macrophages

MORPHOLOGIC DIAGNOSES:  Haired skin, mixed and mucinous salivary glands:  Myoepithelioma, Balb/c mouse, rodent.

CONDITION:  Myoepithelioma

GENERAL DISCUSSION:

PATHOGENESIS:

TYPICAL CLINICAL FINDINGS:

TYPICAL GROSS FINDINGS:

TYPICAL LIGHT MICROSCOPIC FINDINGS:

ADDITIONAL DIAGNOSTICS:

DIFFERENTIAL DIAGNOSIS:

COMPARATIVE PATHOLOGY:

References:

  1. Barthold SW, Griffey SM, Percy DH. Pathology of Laboratory Rodents and Rabbits. 4th ed. Ames, IA: Blackwell Publishing; 2016: 114-115.
  2. Bondoc A, Izawa T, Hirata S, Hasegawa T, Kuwamura M, Golbar HM, Yamate J. Myoepithelioma of the gland of the third eyelid in a dog.  Comp. Pathol. 2014;151:186-189.
  3. Foster RA. Female reproductive system and mammae. In: Zachary JF, ed. Pathologic Basis of Veterinary Disease. 6th ed. St. Louis, MO: Elsevier; 2017: 1174, 1178, 1191-1193.
  4. Gelberg HB. Alimentary system and the Peritoneum, Omentum, Mesentery, and Peritoneal Cavity. In: Zachary JF, ed. Pathologic Basis of Veterinary Disease. 6th ed. St. Louis, MO: Elsevier; 2017: 353.
  5. Goldschmidt M, Pena L, Rasotto R, Zappulli V. Classification and grading of canine mammary tumors.  Pathol. 2011;48(1):117-131.
  6. Miyazaki A, Yonemaru K, Hirata A, Yanai T, Sakai H. Histopathological and immunohistochemical features of atypical epithelial tumours of the gland of the third eyelid in seven dogs.  Comp. Pathol. 2015;152:299-303.
  7. Munday JS, Lohr CV, Kiupel M. Tumors of the alimentary tract.  In: Meuten DJ, ed. Tumors in Domestic Animals.  5th ed. Ames, IA: John Wiley & Sons, Inc.; 2017:544-549.
  8. Schlafer DH, Foster RA. Female genital system. In: Maxie MG, ed. Jubb, Kennedy and Palmer’s Pathology of Domestic Animals. Vol 3. 6th ed. Philadelphia, PA: Elsevier Saunders; 2016:430-461.
  9. Uzal FA, Plattner BL, Hostetter JM. Alimentary system. In: Maxie MG, ed. Jubb, Kennedy and Palmer’s Pathology of Domestic Animals. Vol 2. 6th ed. Philadelphia, PA: Elsevier Saunders; 2016:30.


Click the slide to view.



Click on image for diagnostic series.



Back | Home | Contact Us | Links | Help |