'Insufficient Evidence' to Support Amifostine to Prevent or Treat Oral Mucositis in Cancer Patients
“In our review, we could not demonstrate any evidence to support the use of amifostine for the prevention or the treatment of oral mucositis in any cancer setting,” reported the Mucositis Study Group of the Multinational Association of Supportive Care in Cancer/International Society of Oral Oncology.
Oral mucositis is a common, painful, and sometimes dose-limiting complication of cancer chemotherapy and radiotherapy.
“Complex biological inflammatory pathways are involved in the mucosal toxicity,” the authors wrote. “Generation of oxidative stress and reactive oxygen species (ROS) by chemotherapeutic agents or radiation appears to be a primary event in most pathways leading to mucositis.”
Amifostine is an intravenously-administered organic thiophosphate, believed to function as a free radical scavenger that inhibits up-regulation of inflammatory pathways and “thus, may allow compliance with the planned treatment regimens while preserving the patient's quality of life,” the authors wrote. Amifostine reduces the incidence of acute and late radiotherapy-associated xerostomia among patients with head and neck cancer, for example.
But its efficacy for mucositis in cancer patients has been mixed and controversial, the authors reported.
The team's review of studies published between 1966 and 2010 found many studies to included “major flaws” in methodology (such as lack of controls or randomization), and differences between studies in doses and timing of amifostine administration, cancer therapy modalities, and “the complex pathophysiology of mucosal injury,” that might explain inconsistent and conflicting results, the authors reported.
The conflicting results, insufficient data, and methodological flaws “did not allow any guideline related to the use of amifostine in the prevention of oral mucositis,” they wrote.
“The efficacy of amifostine in the prevention of oral mucositis should be evaluated in new, well-designed, sufficiently powered, randomized, controlled trials,” they concluded.