title: Molecular remission after allogeneic or autologous transplantation of hematopoietic stem cells for multiple myeloma.
abstract: OBJECTIVE
  To assess the clinical relevance of minimal residual disease (MRD) in patients with multiple myeloma (MM), 50 patients were monitored while they were in complete clinical remission (CCR) after autologous or allogeneic stem-cell transplantation.
  
  
  METHODS
  Stringent molecular monitoring using clonal markers based on rearranged immunoglobulin heavy-chain genes was performed in 44 of 50 MM patients in CCR. Molecular clinical remission (MCR) was defined as more than one consecutive negative polymerase chain reaction (PCR) test result.
  
  
  RESULTS
  Twelve (27%) of 44 molecularly monitored patients achieved MCR; four of the 12 became PCR-positive, and one of these four relapsed. In comparison with patients who did not achieve MCR, patients who achieved MCR had a significantly lower relapse rate (41% v 16%; P <.05) and longer relapse-free survival (35 v 110 months; P <.005). Fourteen of 26 patients in CCR who had received allografts were evaluated on a molecular basis: seven (50%) of the 14 achieved MCR and did not relapse; one of the seven remaining patients relapsed. Thirty of 47 patients in CCR who received autografts were evaluated on a molecular basis: five (16%) of the 30 achieved MCR; two of these five became PCR-negative, and one of these two relapsed. Ten of the 25 remaining patients later relapsed. For these nonrandomized groups, the higher MCR rate after allograft procedures was statistically significant (P <.01; Fisher's exact test).
  
  
  CONCLUSIONS
  MCR can be obtained in a relatively high proportion of MM patients who have achieved CCR after undergoing allograft procedures and in a smaller fraction of patients after undergoing autograft procedures. In approximately one fourth of MM patients who achieve CCR after transplantation, it may be possible to keep the disease burden constantly below the PCR threshold. Because MCR was associated with prolonged relapse-free survival, these patients could have a relatively favorable clinical outcome.
authors.affiliation: Institute of Hematology and Medical Oncology "Seràgnoli," University of Bologna, Italy. gmartino@kaiser.alma.unibo.it
authors.forename: G
authors.initials: G
authors.lastname: Martinelli
authors.forename: C
authors.initials: C
authors.lastname: Terragna
authors.forename: E
authors.initials: E
authors.lastname: Zamagni
authors.forename: S
authors.initials: S
authors.lastname: Ronconi
authors.forename: P
authors.initials: P
authors.lastname: Tosi
authors.forename: R M
authors.initials: RM
authors.lastname: Lemoli
authors.forename: G
authors.initials: G
authors.lastname: Bandini
authors.forename: M R
authors.initials: MR
authors.lastname: Motta
authors.forename: N
authors.initials: N
authors.lastname: Testoni
authors.forename: M
authors.initials: M
authors.lastname: Amabile
authors.forename: E
authors.initials: E
authors.lastname: Ottaviani
authors.forename: N
authors.initials: N
authors.lastname: Vianelli
authors.forename: A
authors.initials: A
authors.lastname: de Vivo
authors.forename: A
authors.initials: A
authors.lastname: Gozzetti
authors.forename: S
authors.initials: S
authors.lastname: Tura
authors.forename: M
authors.initials: M
authors.lastname: Cavo
mesh_terms: D000328:Adult; D014408:Biomarkers, Tumor / Q000032:analysis; D004273:DNA, Neoplasm / Q000032:analysis; D005260:Female; D015321:Gene Rearrangement; D005819:Genetic Markers; D018380:Hematopoietic Stem Cell Transplantation; D006801:Humans; D008297:Male; D008875:Middle Aged; D009101:Multiple Myeloma / Q000235:genetics / Q000628:therapy*; D018365:Neoplasm, Residual; D016133:Polymerase Chain Reaction; D012074:Remission Induction; D012189:Retrospective Studies; D016019:Survival Analysis; D014182:Transplantation, Autologous; D014184:Transplantation, Homologous
chemical_list: D014408:Biomarkers, Tumor; D004273:DNA, Neoplasm; D005819:Genetic Markers