<unk>  is a malignant tumor whose cause is the treatment (usually radiation or chemotherapy) which was used for a prior tumor. It must be distinguished from Metastasis from the prior tumor or a relapse from it since a<unk>  is a different tumor.
Secondary malignant neoplasm
Secondary trauma
Malignant transformation
Mineral deficiency
Fungal infection
Psychogenic disease
Occult fracture
Vitamin deficiency