ORIGINAL ARTICLE Multiple myeloma-associated amyloidosis is an independent high-risk prognostic factor J. Vela-Ojeda & M. A. García-Ruiz Esparza & Y. Padilla-González & E. Sánchez-Cortes & J. García-Chávez & L. Montiel-Cervantes & E. Reyes-Maldonado & A. Majluf-Cruz & H. Mayani Received: 14 October 2007 / Accepted: 27 June 2008 / Published online: 22 July 2008 # Springer-Verlag 2008 Abstract Several prognostic factors have been recognized in patients with multiple myeloma (MM). Among the most important are: the serum levels of β2-microglobulin, albumin, and LDH; the labeling index; and an abnormal karyotype. Patients with amyloidosis (AL) have poor prognosis; however, little is known concerning the prog- nostic significance of AL associated to MM. In 201 consecutive patients with de novo MM, we performed a fat-pad biopsy needle aspiration (FPBNA) that was stained with Congo red. Sixty eight (34%) patients had AL and a poorer prognosis disease: lower performance status, pres- ence of B symptoms, higher LDH and calcium values, and worse response to chemotherapy. Cox regression model for overall survival detected three variables having independent prognostic significance: the presence of AL (RR=3.4, P <0.004), serum albumin levels <3.5 g/dl (RR 3.2, p <0.005), and patients not achieving complete remission or very good partial remission (RR 2.9, p <0.02). In 28% of patients with de novo MM, FPBNA was useful to detect incidental amyloidosis. During follow-up, 69% of these patients had symptoms of AL. Excluding 16 patients with obvious symptoms of AL at diagnosis, overall survival was worse in patients who developed later symptoms of AL. MM- associated AL represents a poorer prognosis disease even in the absence of symptoms at diagnosis, and this specific association may be considered as an independent high-risk prognostic factor. The routine study of periumbilical fat-pad tissue should be mandatory in all patients with MM. Keywords Multiple myeloma . Amyloidosis . Prognostic factors Introduction Multiple myeloma (MM) is a clonal malignant disease of plasma cells characterized by the production of a monoclonal immunoglobulin, anemia, lytic bone lesions, and renal failure [13]. Several prognostic factors have been recognized for this disorder; however, the most important are: the serum level of β2-microglobulin, albumin, and LDH [10]; the labeling index [20]; and abnormal karyotypes [23]. Ann Hematol (2009) 88:59–66 DOI 10.1007/s00277-008-0554-0 DO00554; No of Pages J. Vela-Ojeda : M. A. García-Ruiz Esparza : Y. Padilla-González : E. Sánchez-Cortes : J. García-Chávez : L. Montiel-Cervantes Hematology Department, Unidad Médica de Alta Especialidad, Hospital de Especialidades Centro Médico Nacional La Raza, IMSS, México D.F, México J. Vela-Ojeda : J. García-Chávez : L. Montiel-Cervantes Hematology Research Unit, Unidad Médica de Alta Especialidad, Hospital de Especialidades Centro Médico Nacional La Raza, IMSS, México D.F, México A. Majluf-Cruz Hemostasis, Thrombosis, and Atherogenesis Research Unit, Hospital General Regional Gabriel Mancera, IMSS, México D.F, México H. Mayani Hematopoyesis and Oncology Research Unit, Hospital de Oncología, Centro Médico Nacional Siglo XXI, IMSS, México D.F, México J. Vela-Ojeda (*) Apartado Postal 14-878, CP 07001 México D.F., México e-mail: velaj12x@prodigy.net.mx J. Vela-Ojeda : L. Montiel-Cervantes : E. Reyes-Maldonado Morphology Department, National School of Biological Sciences, Instituto Politécnico Nacional, México D.F., México