title: Solitary plasmacytomas: outcome and prognostic factors after definitive radiation therapy.
abstract: BACKGROUND
  The objective of this study was to review the outcome of patients with solitary plasmacytoma (SP) after definitive radiation therapy.
  
  
  METHODS
  The authors retrospectively reviewed 84 patients with SP who were diagnosed and treated at The University of Texas MD Anderson Cancer Center during 1988 to 2008. The impact of tumor anatomic site, tumor size, and the presence of serum and urinary paraprotein at diagnosis was assessed on local control, survival, and the risk of developing multiple myeloma (MM).
  
  
  RESULTS
  Fifty-nine patients (70%) had bone SP, and 25 patients (30%) had extramedullary SP. Serum paraprotein was present in 39 patients (46%). The median radiation dose was 45 grays (Gy) (range, 36-53.4 Gy). Local control was achieved in 77 patients (92%). Neither radiation dose nor tumor size predicted local control. The 5-year rate of progression to MM was 47% and was higher for patients with bone SP (56% vs 30% for extramedullary SP; P = .021), and patients who had serum paraprotein detected at diagnosis (60% vs 39%; P = .016). On univariate analysis, patients aged <60 years and men had higher rates of progression to MM, although the differences were not significant (P = .048 and P = .29, respectively). Multivariate analysis revealed that bone location and serum protein at diagnosis were associated statistically with progression to MM. The 5-year overall survival rate for the entire patient cohort was 78%, and no difference was observed between patients who had bone SP versus extramedullary SP (76% vs 85%, respectively; P = .274).
  
  
  CONCLUSIONS
  The current results indicated that definitive radiation therapy for SP can provide excellent local control. Progression to MM remains the main problem and is more common among patients with bone SP and those who have serum paraprotein detected at diagnosis.
authors: Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.
authors: Valerie
authors: V
authors: Reed
authors: Jatin
authors: J
authors: Shah
authors: L Jeffery
authors: LJ
authors: Medeiros
authors: Chul S
authors: CS
authors: Ha
authors: Ali
authors: A
authors: Mazloom
authors: Donna M
authors: DM
authors: Weber
authors: Isidora Y
authors: IY
authors: Arzu
authors: Robert Z
authors: RZ
authors: Orlowski
authors: Sheeba K
authors: SK
authors: Thomas
authors: Ferial
authors: F
authors: Shihadeh
authors: Raymond
authors: R
authors: Alexanian
authors: Bouthaina S
authors: BS
authors: Dabaja
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001859:Bone Neoplasms / Q000097:blood / Q000175:diagnosis* / Q000209:etiology / Q000652:urine; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009101:Multiple Myeloma / Q000097:blood / Q000175:diagnosis* / Q000209:etiology / Q000652:urine; D009381:Neoplasms, Radiation-Induced / Q000097:blood / Q000175:diagnosis* / Q000209:etiology / Q000652:urine; D010266:Paraproteins / Q000378:metabolism* / Q000652:urine*; D010954:Plasmacytoma / Q000401:mortality / Q000532:radiotherapy*; D011379:Prognosis; D011878:Radiotherapy / Q000009:adverse effects*; D012189:Retrospective Studies; D015996:Survival Rate; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D010266:Paraproteins