Canine bicavitary carcinomatosis with transient needle tract metastasis diagnosed by multiplex immunocytochemistry

Abstract

A 6-year-old, male castrated, mixed-breed dog was referred to the James L. Voss Veterinary Teaching Hospital at Colorado State University for bicavitary effusion. On examination, the dog was tachycardic and tachypneic with bilaterally decreased lung sounds. Thoracic and abdominal ultrasonic examination revealed pleural and peritoneal effusions, which were aspirated and submitted for fluid analysis and cytology. Both cavity fluids were classified as exudates with a large population of vacuolated mononuclear cells. Multiplex immunocytochemistry (ICC) for cytokeratin and vimentin demonstrated exclusively cytokeratin expression, indicating these cells were of epithelial origin. A full diagnostic evaluation was performed, including CBC, clinical chemistry, a pet-side test for heartworm disease, ehrlichiosis, Lyme disease, and anaplasmosis, imaging modalities of thorax, abdomen, and heart, urinalysis, and fine-needle aspirations of spleen, liver, and popliteal lymph nodes. The dog was diagnosed with pleural and peritoneal carcinoma with presumed carcinomatosis. A single dose of intracavitary carboplatin was administered before discharge, and over a period of 2 weeks, 5 thoracocenteses were performed. A subcutaneous mass was noted at a thoracocentesis site one week after initial presentation. Cytology of the mass was consistent with carcinoma, and neoplastic seeding of the tumor cells from the thoracocentesis was suspected. The dog was euthanized 15 days after the first visit, and a necropsy was performed. Findings were consistent with carcinomatosis secondary to anaplastic pulmonary carcinoma with transient subcutaneous seeding of neoplastic cells during routine thoracocentesis. This case demonstrates the utility of multiplex ICC in the clinical setting.

Rapid multiple immunofluorescent staining for the simultaneous detection of cytokeratin and vimentin in the cytology of canine tumors

“…In a recent case report, pleural and peritoneal fluid cytology preparations were examined using immunofluorescence, for which carcinoma could be diagnosed. 7 We recently developed an enzymebased rapid ICC method and validated its utility in clinical cases, 8,9 and although this rapid method may be a practical and useful tool, some limitations remain, including nonspecific background staining and/or weak immunostaining. DOI: 10.1111/vcp.12598 In the present study, we developed a rapid multiple immunofluorescent (RMIF)-ICC method for cytokeratin and vimentin detection on a single cytologic preparation and evaluated the practicality of using this method in veterinary clinics compared with the enzymebased rapid ICC.…”

“…The use of immunofluorescence may help to overcome these limitations. In a recent case report, pleural and peritoneal fluid cytology preparations were examined using immunofluorescence, for which carcinoma could be diagnosed . We recently developed an enzyme‐based rapid ICC method and validated its utility in clinical cases, and although this rapid method may be a practical and useful tool, some limitations remain, including nonspecific background staining and/or weak immunostaining.…”

Clinical, CT, and ultrasonographic features of canine and feline pleural and peritoneal carcinomatosis and sarcomatosis

“…1,2 Sarcomatosis describes a similar spread of mesenchymal tumors. 3 Carcinomatosis and sarcomatosis affecting the peritoneal 4,5 pleural, 6,7 and cerebrospinal cavities 8,9 have been reported in dogs and cats. Presence of carcinomatosis or sarcomatosis is generally associated with a poor prognosis 2 and has limited therapeutic options, including intracavitary or combination chemotherapy, which have little success.…”

“…The imaging features of pleural and peritoneal carcinomatosis and sarcomatosis have been documented in association with various primary tumors in dogs and cats in small case-series and individual case reports. [4][5][6][7]12,15 The radiographic appearance of peritoneal carcinomatosis in dogs and cats typically includes a generalized loss of serosal detail, alongside diffuse, patchy, and poorly defined soft tissue lesions throughout the abdomen. 15 Ultrasonographically, lesions in cats have been described as nodular, poorly defined, hypoechoic masses communicating between the visceral and parietal peritoneal layers.…”

Multiplex fluorescent immunocytochemistry for the diagnosis of feline infectious peritonitis: Determining optimal storage conditions

“…Multiplex fluorescent ICC (MF‐ICC) assays are more sensitive than chromogenic ICC, quicker to perform, permit compensation of inherent background immunostaining via detection software programs, and allow for easier multiplexing and detection of more than one antigen in a single target cell of interest 7 . Applied to an FIP diagnosis, such an assay can capitalize on the hallmark gain of tropism for macrophages in FIPV that is not observed in FECV.…”