Endogenous lipid (cholesterol) pneumonia associated with bronchogenic carcinoma in a cat

An 11-year-old, female domestic longhair was presented for dyspnea, vomiting, and left forelimb lameness. A mass in the left caudal lung lobe was seen on thoracic radiographs. The mass was resected during thoracotomy, and histopathology confirmed a diagnosis of endogenous lipid pneumonia. The cat recovered slowly from surgery and was euthanized 11 days following discharge because of persistent respiratory difficulties. Necropsy findings included lipid pneumonia and bronchogenic carcinoma, with probable tumor metastasis to the small intestine, spleen, kidney, and left triceps muscle.