Cryotherapy as Prophylaxis Against Oral Mucositis After High-dose Melphalan and Autologous Stem Cell Transplantation for Myeloma: a Randomised, Open-label, Phase 3, Non-inferiority Trial Comparing Two and Seven Hours of Cryotherapy.

We searched MEDLINE and PubMed with the following phrases: "oral mucositis", "oral toxicity", "cryotherapy", "myeloma", "autologous haematopoietic stem cell transplantation", "randomised trial" and "high-dose melphalan".

Oral mucositis, which is a side effect of high-dose chemotherapy, has a major negative impact on the quality of life and survival of patients who undergoing autologous haematopoietic stem cell transplantation (auto-HSCT). For patients with myeloma cryotherapy gives a significant reduction in oral mucositis. The mechanism of action is suggested to be vasoconstriction that is induced by the cooling of the oral mucosa, thereby protecting it from the cytotoxic effects of the chemotherapy. The therapeutic efficacy of cryotherapy in this setting has been confirmed in several trials, it is currently regarded as the standard of care prophylactic regimen for oral mucositis in patients undergoing auto-HSCT for myeloma. However, the long duration of the treatment (7 hours), as reported in the original, placebo-controlled study in 2006, has been associated with significant discomfort for the patients, with negative consequences for compliance.

Uncontrolled trials have previously tested cryotherapy for less than 7 hours in patients with myeloma who receive auto-HSCT. At the time of the planning of the current study in 2014, those results were not yet confirmed in any randomised trial. However last year a randomised trial was published, showing that 2-hour cryotherapy is equally as effective as 6-hour cryotherapy in preventing oral mucositis in patients with myeloma who are treated with high-dose melphalan. The present prospective, randomised study aimed to investigate whether 2 hours of cryotherapy is as effective as 7 hours of cryotherapy in protecting against oral mucositis those patients who are subjected to high-dose melphalan as a conditioning agent for auto-SCT for myeloma.