Mucositis and stomatitis
Painful inflammation and ulcers of the mouth and gut lining, because the fast-dividing cells that renew it are hit by chemotherapy and radiotherapy. It can make eating impossible and is a major reason patients on head and neck chemoradiation need feeding tubes.
Severe oral mucositis affects most patients receiving head and neck chemoradiation and high-dose conditioning for transplant, and a minority on 5-FU, methotrexate and taxanes; everolimus and other mTOR inhibitors cause a distinct stomatitis prevented by dexamethasone mouthwash (SWISH). Oesophagitis follows thoracic radiotherapy. Management is analgesia (often opioids), oral care, palifermin in transplant, photobiomodulation, and nutritional support; mucositis prolongs hospital stays, causes dose reductions and increases infection through the damaged barrier. It is the classic example of on-target toxicity to normal proliferating tissue.