Background and significance: The field of terminology and assessment of oral and gastrointestinal mucosal injury caused by high-dose cancer therapies in cancer patients has undergone important evolution in recent years. The advances are important for several clinical and research reasons. These reasons include improved patient management and design and conduct of clinical trials based on molecularly targeted therapies. For several decades leading up to the 1980s, terminology was characterized by varying use of "mucositis" and "stomatitis" to describe oral mucosal inflammatory changes and ulceration caused by cancer treatments. In addition, oral mucositis was viewed principally as an epithelial event and one that likely did not intersect with causative mechanisms associated with gastrointestinal mucositis. The term "stomatitis" was directed to oral toxicities and seemed to isolate these conditions from parallel events occurring throughout the alimentary tract and potentially other tissues as well. These perspectives and varying use of these terms resulted in several dilemmas, including (1) difficulty in accurately reporting incidence and severity of oral mucositis and, (2) an under-appreciation of potential significance of alimentary tract mucosal toxicity relative to overall course of therapy, patient quality of life, and in some cases, survivorship. These and related components of the model relative to mucositis have undergone strategic shifts over the past 15 years. A 1989 National Institutes of Health Consensus Development Conference targeted oral mucositis research as one of the key areas for investigation relative to causation, clinical impact, and potential links with other complications in cancer patients. Research in this area over the past 15 years has evolved such that oral and gastrointestinal mucositis are now appropriately framed as a continuum of pathobiologic changes over time, with clinical impact that may well contribute to overall symptom clustering in selected patient cohorts.
Objectives: This paper will review history, current status, and new research directions associated with terminology and assessment of mucosal injury in cancer patients in the context described above.