“The MASCC/ISOO clinical practice guidelines support the use of new agents in patients receiving head and neck radiotherapy, based on available evidence. These agents include benzydamine mouthrinse [for] patients receiving radiotherapy up to 50 Gy without concurrent chemotherapy (based on level I evidence) and a suggestion for low-level laser therapy (LLLT) in patients receiving radiotherapy in the absence of concurrent chemotherapy (based on level III evidence). The guidelines also support the use of 0.2% morphine mouthwash (level III evidence) and 0.5% doxepin mouthwash (level IV evidence) to reduce pain due to oral mucositis.”
Dental care before initiation of radiotherapy or chemoradiation is crucial, experts agree.
“Absolutely every patient who is about to undergo radiation therapy that includes the mouth should have a pretherapy dental evaluation,” Sonis emphasizes. Preradiation dental evaluation and treatment is a mandatory component of treatment plans, he says.
The major goals of dental evaluation are twofold, he explains: first, identification and elimination of existing or potential sources of infection, and second, elimination of any sources of mucosal irritation such as fractured teeth.
“We still don’t know if, or how, the microbiome might contribute to mucositis, although we do know that attempts at reducing the oral bacterial load have, generally, proved inadequate in preventing mucositis,” cautions Sonis. “Having said that, we also know that patients with clean mouths do better than those with poor hygiene. Since dentures act both as irritants and as ‘bug habitats and transporters,’ their use should be limited in patients who are receiving radiation therapy and protheses should be cleaned and disinfected.”
“Oncology nurses are in an excellent position to screen for oral health problems prior to radiotherapy,” Sonis says. “Simple screening questions to assess the level of dental health (last dental visit, pain, ability to eat, etc.) are often helpful.”
Every patient should be screened before radiation begins, he reiterates—“preferably in enough time to allow for healing from any [dental] procedures that are required.” At least 3 weeks should elapse between a tooth extraction and commencement of radiation, he advises.
The field has experienced repeated disappointments over seemingly promising therapies that did not pan out.9 Fortunately, the research and development pipeline is rich, says Sonis. “I’m optimistic that we’ll have an effective preventive treatment within the next few years.”
“A large variety of agents have been tested for radiation-induced oral mucositis, with most proving ineffective,” Lalla agrees. “This is an active field of research and a number of agents are in clinical trials or other stages of development for radiation-induced oral mucositis.”
Low-level laser therapy might reduce the incidence of severe chemoradiation-associated oral mucositis, and improve quality of life for patients with head and neck cancers.10 However, Sonis and others urge caution because LLLT’s impacts on tumor behavior have not yet been studied.
Anti-inflammatory agents are a promising strategy for preventing and treating oral mucositis, but the evidence base is immature and inconsistent, note Lalla and coauthors of the MASCC/ISOO Mucositis Study Group’s systematic review of the published literature.11 (Based on that review, misoprostol mouthrinse is not recommended for preventing radiotherapy-associated oral mucositis in patients with head and neck cancer, however.11)
Sonis is particularly enthusiastic about the promise of genomics and personalized medicine in treatment planning and prevention of oral mucositis and other regimen-related toxicities, as increasing understanding of the biologic pathways involved in the pathogenesis of radiation- and chemotherapy-mediated injury continue to emerge.