One of the most common side effects of cancer treatment with chemotherapy or radiation
Occurs in almost all cases of head or neck radiation
20-80% of people who receive chemotherapy
Major dose limiting toxicity of chemotherapy and head and neck radiation therapy
Mucositis
Oral candidiasis
Myositis 
Herpes simplex virus infection
Dermatitis
Acute graft-versus-host disease
Alopecia
Conjunctivitis 