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.

The conditioning therapy used in connection with haematopoietic stem cell transplantation (HSCT) can induce painful oral mucositis, which has negative impacts on patient quality of life and survival, as well as on health-care costs. While cooling of the oral mucosa (cryotherapy) is regarded as standard prophylaxis against oral mucositis, the long duration of the treatment affects compliance owing to side effects. In this prospective, randomised trial, 94 patients (62 males/32 females; median age 59 years, range 34-69) with a diagnosis of myeloma who were undergoing autologous HSCT were randomised 1:1 to receive cryotherapy for 7 h (N = 46) or 2 h (N = 48). Oral mucositis was evaluated prospectively. No significant difference was observed with respect to the proportion of patients who showed grades 3 and 4 toxicity according to the WHO scale (2.1 and 4.3% for 2 and 7 h, respectively; 95% CI -0.09 to 0.049; p = 0.98) as between the groups. Two hours of cryotherapy was as effective as 7 h in terms of protecting against severe oral mucositis in connection with autologous HSCT for myeloma. This trial is registered with ClinicalTrials.gov (NCT03704597).