Mucositis has been described as a complex physiologic process that can be examined in five stages: initiation, primary damage response, signal amplification, ulceration, and healing (Fig. 11.1).

On initial presentation of OM, the oral mucosa first shows erythema which then progresses to erosion and ultimately ulceration. Ulcerations are typically covered by a white fibrinous pseudomembrane. Lesions will heal approximately 2–4 weeks after the last dose of the offending chemotherapy or radiation therapy. In the case of immunosuppressed patients, resolution of OM usually coincides with granulocyte recovery (Lalla et al. 2008). Chemotherapy-induced OM is limited to nonkeratinized surfaces such as the lateral and ventral tongue, buccal mucosa, and soft palate (Lalla et al. 2008). Radiation-induced OM occurs in the radiation field with nonkeratinized tissue affected more often. Patients receiving increasing cumulative doses beyond 30 Gy will be more severely affected (Sonis 2007; Lalla et al. 2008). The clinical course of mucositis can be complicated by infection, particularly in the immunocompromised patient.

Historically, mucositis measurement and assessment in pediatrics have relied on tools developed for adults (Tomlinson et al. 2009). Reliable oral assessment is essential to facilitate management strategies or implement clinical trials in mucositis prevention and treatment (Tomlinson et al. 2007, 2009). The scales currently utilized to assess pediatric OM do not address practical issues such as mechanisms for optimal visualization of the oral cavity and approaching an uncooperative child. There are also limitations to reporting subjective and functional domains in the child (Tomlinson et al. 2007).

Simple instruments such as the World Health Organization (WHO) grading system and the National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events are scales that range from 0 (with no symptoms) to 4 or 5 (worst symptoms possible) (Fig. 11.2). Generally these scales are based on the ability to eat and drink combined with objective signs of mucositis. These instruments are utilized by pediatric oncology groups as part of toxicity criteria measurement. They are seen to be the most relevant scales for clinical management as a global score is achieved readily (Sonis et al. 2004). However, these simple scales may underreport mucositis if effective analgesia is administered to the patient (Sonis 2009).

The Oral Mucositis Assessment Scale (OMAS) was developed by a panel of experts to be an objective, simple, and reproducible assessment tool to be applied to multicenter clinical trials of mucositis (Sonis et al. 1999). The OMAS measures degree of ulceration, pseudomembrane formation, and mucosal erythema in specific mouth sites (Sonis et al. 1999) (Fig. 11.2). Testing has demonstrated that the OMAS is reliable and valid in adults with the only reported limitation being that patients with severe mucositis had difficulty undergoing repeated examinations (Sonis et al. 1999). Sung et al. (2007) demonstrated that the OMAS is valid in the measurement of mucositis in children ≥6 years of age.

An example of a combined scale that includes both objective and subjective experiences as well as functional dimensions is the Oral Assessment Guide (OAG) (Eilers et al. 1988). The OAG was designed primarily as a clinical tool and is useful for recording the condition of the oral cavity (Eilers et al. 1988). The OAG consists of numerical and descriptive ratings in eight categories including voice, swallowing, lips, tongue, saliva, mucous membranes, gingivae and teeth. Each descriptive category is assessed on a numeric scale from 1 to 3 with the overall oral assessment score the sum of the eight categories (Eilers et al. 1988) (Fig. 11.2). Chen et al. (2004) used the OAG to assess children with leukemia and lymphoma undergoing chemotherapy and were able to demonstrate content validity of the instrument.

Tomlinson et al. (2008a, b, c) identified four main areas of concern from the existing literature in mucositis assessment and tool development in the pediatric oncology population: (1) the challenge of oral assessment in children with relation to age and cooperation; (2) the need for proxy responses, while recognizing the challenges of reporting pain and function attributed to oral mucositis; (3) the need for an instrument that is simple, quick to complete and easy to use in almost all children; and (4) educational considerations. To address these concerns, their group developed the Children’s International Mucositis Evaluation Scale (ChIMES; Fig. 11.3), an assessment instrument for both child self-report and parent proxy-report (Tomlinson et al. 2009). ChIMES assesses three main areas: (1) pain (i.e., pain assessment, amount of pain medication received), (2) function (i.e., effect on eating, drooling/pooling of saliva, effect on drinking), and (3) appearance (i.e., presence of ulcers) (Tomlinson et al. 2009). ChIMES has been shown to be understandable, with content validity and acceptability, and has been prospectively validated in a multicenter cohort of children receiving chemotherapy and after HSCT (Tomlinson et al. 2009, 2011; Jacobs et al. 2013).

In recent years there has been an increase in research regarding the prevention and treatment of mucositis. However, evidence-based interventions remain limited, especially in pediatric patients. Generally, the clinical focus continues to be on palliation of the symptoms of mucositis (Eilers and Million 2011). In a Cochrane review, Clarkson et al. (2010) showed that there is limited evidence that low-level laser therapy (LLLT) may be beneficial in the treatment of OM. In a separate Cochrane analysis Worthington et al. (2011) reported that ten agents showed potential benefit in OM prophylaxis; these agents were reviewed by Eilers and Million (2011) and are summarized in Table 11.2.