Inflammatory bowel disease and small cell lymphoma are common causes of chronic illness in older cats. Distinguishing and managing them well restores quality of life.
Untreated IBD and SCL cause progressive weight loss, malnutrition, and systemic illness that dramatically reduce quality of life. The remarkable response of SCL to chlorambucil treatment — with many cats returning to near-normal weight and activity — makes treatment a significant welfare intervention. The challenge is that diagnosis requires biopsy (either endoscopic or surgical), which is invasive. However, the welfare benefit of accurate diagnosis and appropriate treatment justifies the investigation.