Myeloma after local external beam radiotherapy jet: Is it a new entity?

Multiple myeloma, also known as Kahler's disease, is a cancer of plasma cells that abnormally accumulate in bone marrow. Radiation therapy may be indicated in multiple myeloma to relieve pain, alleviate spinal cord compression or reduce tumor mass. We report the case of a patient presenting a multiple myeloma, treated with radiation therapy for a spinal cord compression, who developed, eleven months later, an in-field subcutaneous relapse. We called this phenomenon myeloma appearance after local external beam radiotherapy jet (MAALEJ). A review of literature was performed trying to explain this uncommon relapse feature.