Open AccessClinicopathologic, immunohistochemical, and ultrastructural features of histiocytic sarcoma in a chinchilla ( Chinchilla lanigera )
Author(s) -
Enomoto Kaoru,
Tsutsumitani Chihiro,
Asakawa Midori Goto
Publication year - 2022
Publication title -
veterinary medicine and science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.485
H-Index - 11
ISSN - 2053-1095
DOI - 10.1002/vms3.645
Subject(s) - pathology , histiocytic sarcoma , histiocyte , biology , chinchilla , stain , lymph , autopsy , staining , anatomy , medicine
A 9‐year‐old intact female chinchilla ( Chinchilla lanigera ) was presented to a referring veterinarian due to small, multiple cervical nodules that had been rapidly increasing in size and number. Cytology of the nodules revealed sheets of pleomorphic round cells that were morphologically most compatible with histiocytic sarcoma. Histologically, the nodules were fairly demarcated, partially infiltrative, densely cellular neoplasm, and was composed of pleomorphic large round cells arranged in sheets. Special stains for bacteria (Gram stain and Ziehl–Neelsen stain) and fungi (periodic acid‐Schiff stain) were all negative. On immunohistochemistry, the neoplastic cells showed strong cytoplasmic positivity for Iba‐1 and CD204, but were negative for CD3 and CD20. Transmission electron microscopy failed to detect Birbeck's granules in the cytoplasm of the neoplastic histiocytes. The chinchilla received chemotherapy with lomustine but died spontaneously on day 62 despite treatment. Autopsy with histopathologic examination revealed disseminated histiocytic sarcoma involving the bone marrow, bronchial lymph nodes, nasal cavity, lung, heart, stomach, pancreas, pancreatic lymph nodes, liver, spleen, and kidney. To the best of our knowledge, this is the first report of disseminated histiocytic sarcoma in chinchillas.