Lymphoma- MANY lymphoblast cells with prominent nucleoli
Eosinophilic inflammation (> 15% Eos)- think allergy, parasite, etc.
Mast cell- Mast cell tumors are common in dogs but we will also see them in inflammatory reactions, especially in skin, airway or reproductive tract. Remember that they are characterized by large numbers of purple granules and abundant cytoplasm.
Lymph node aspirate
Epitheliod cells in the lymph node is an inappropriate place for them to be. SCC metastasized to l.n.
Epitheliod cell pleomorphism. Much variability- signs of malignancy
Normal epitheliod cells. Uniform. Exceptions: Round cell tumors with be uniform.
Monotonous population of cells. Fibrosarcoma in a dog.
Epitheliod cells of a SCC. Inflammation is not typically present with the exception of SCC's because of keratin stimulation of an inflammatory rxn.
Cellular piling (may suggest malignancy)
Large, abnormal nuclei with abnormally clumped chromatin. Signs of malignancy.