Prospective Cohort of Single-dose Radiotherapy for Painful Bone Lesions in Multiple Myeloma

Inclusion Criteria: * Biopsy of plasma cell neoplasm with bone lesion treatable with radiotherapy; * Age between 18 and 85 years old; * Performance on the ECOG scale less than or equal to 2. * Not using systemic therapies for 4 weeks OR being on maintenance therapy with the same drug for at least 4 weeks before radiotherapy. Exclusion Criteria: * Refusing to sign or inability to understand the consent term; * Pain less than 2/10 on the numeric pain rating scale; * Change in systemic treatment scheme, including use of bone metabolism modulation drugs, up to 4 weeks before radiotherapy treatment; * Technical incapacity for the treatment, including, but not limited to, weight greater than 115Kg, inability to abduct the limb to be treated in appendicular bones, intolerable pain to remain in the treatment position; * Previous cancer and previous oncological treatments; * Previous autoimmune diseases, even if controlled; * Current pregnancy.