Fine Needle Aspiration: Osteomyelitis and Osteosarcoma in Dogs
Background: Osteomyelitis is an inflammation of the bone, bone marrow, endosteum, periosteum and vascular channels. Chronic osteomyelitis can result from inadequate treatment of acute bone inflammation, which indicates the importance of rapid and accurate diagnosis to better therapeutic conduct of the osteomyelitis being treated. Appendicular osteosarcoma is the main primary malignant and nonhematopoietic osteogenic tumor in dogs. It appears spontaneously in the appendicular skeleton with a relevant incidence both in dogs and in human children. Unfortunately, it is an aggressive neoplasm with high rates of metastasis regardless of the species. The high rate of lethality is due to the terrible survival prognosis for patients with lung metastasis and due to chemotherapy refractoriness. For human patients, the chemotherapeutic treatment, based on a prior anatomopathological diagnosis, results in a better rate of survival as it reduces metastases. However, this approach is not often explored in veterinary medicine, which features amputation as the traditional approach, followed by chemotherapy.
Objective: Verify the morphological expression of the parameters used in the cytopathological diagnosis through fine needle aspiration cytology of osteomyelitis and spontaneous osteosarcomas in dogs from varying breeds, including mixed-breeds. The study also aims to demonstrate that the fine-needle aspiration technique is able to carry out efficiently the diagnosis of osteomyelitis as well as canine osteosarcoma.
Methods: This study verified, through optical microscopy, the morphological expression of parameters used in the cytopathological diagnosis of osteomyelitis and osteosarcomas in twenty dogs of different breeds, including mixed-breeds, and then conducted an analysis of possible concordances between these parameters. The cytological assay was conducted through fine needle aspiration cytology, using Giemsa and Papanicolaou stain on the microscope slides. The histopathological assay was conducted through the use of biopsies of surgical specimens, which were processed according to the standard procedures and stained with hematoxylin-eosin. The tumors were classified based on the guidelines proposed by the World Health Organization.
Results: There was malignancy criteria significantly repeated both at cytopathological and at histopathological assays.
Conclusion: These findings show us that the cytopathological assay through aspiration may be used as a trustworthy diagnostic method for osteomyelitis and osteosarcomas in dogs..
Marcela da CG and Noeme SR