Diagnosis and treatment of chylothorax associated with lymphoblastic lymphosarcoma in four cats.

Chylothorax was diagnosed in 4 cats with lymphoblastic lymphosarcoma. Clinical findings included dyspnea, muffled heart sounds, and noncompressibility of the cranial portion of the thorax. All cats had high pleural fluid triglyceride concentration. Lymphosarcoma was diagnosed by cytologic evaluation of pleural fluid in 3 cats and by histologic evaluation of a cranial cervical lymph node in 1 cat. Two cats were euthanatized prior to any treatment, and the other 2 cats were managed by thoracic drainage, chemotherapy, and/or irradiation.