Lymphomatoid granulomatosis is a condition that involves the infiltration of the lungs by cancerous lymphoid cells. Metastasis may occur in other parts of the body like liver, heart, spleen, pancreas, and kidney. This is not breed or gender-specific, but is more common in large and purebred dogs. Respiratory symptoms are often seen which aggravate over time. Some of the common symptoms include cough, difficulty breathing, exercise intolerance, weight loss, Lack of appetite and fever.