The goal of this clinical trial is to learn if photobiomodulation works to prevent severe oral mucositis in patients who are undergoing allogeneic hematopoietic cell transplantation. The main questions it aims to answer are:
Does 1) intraoral , 2) extraoral, or 3) combined intraoral/extraoral photobiomodulation have optimal prevention/therapeutic effect in prevention of oral mucositis in patients undergoing myeloablative allogeneic hematopoietic stem cell transplantation (alloHSCT).
Participants will:
Be randomized to one of the three treatment arms Receive daily photobiomodulation therapy (from beginning of transplant conditioning through Day +20 after transplantation) Be evaluated for oral mucositis and symptoms daily Visit the clinic once every 2 weeks for checkups and tests Keep a diary of their symptoms and the number of times they use a rescue inhaler