myeloma blood cancer prognosismyeloma treatment and prognosismalignant myeloma prognosisasymptomatic myeloma prognosissmouldering myeloma prognosissmoldering myeloma prognosismyeloma prognosis in the elderlystage 2 myeloma prognosisplasma myeloma prognosismetastatic multiple myeloma prognosismultiple myeloma relapse prognosisaggressive multiple myeloma prognosis