To determine the prognostic indicators in patients with solitary plasmacytoma of bone (SPB) of the spine.
Population-level estimates for prognosis among patients with SPB of the spine are still lacking. Sociodemographic and clinical predictors of outcome have not been well characterized.
The Surveillance, Epidemiology, and End Results Registry was used to identify all patients with SPB of the spine from 1995 through 2014. Associated population data were used to determine annual incidence and limited-duration prevalence. Overall survival (OS) estimates were obtained using the Kaplan–Meier method and compared across groups using log-rank test. A Cox regression model was used for multivariate analysis of survival. Logistic regression was performed to identify predictors of the progression to multiple myeloma (MM).
The incidence and prevalence of the disease increased during the study period. Spinal SPB most commonly affected older people (>50) with a male preponderance. The median OS were 74.0 months. The 5 and 10-year survival rates for these patients were 56.1% and 36.7%, respectively. On multivariable analyses, older age, and surgery without radiotherapy were correlated with poor survival of patients with spinal SPB. The 3-year probability of progression to MM was 10.1%. Patients aged >70 years were associated with progression to MM. There was no significant association between the methods of surgical resection (radical or local/partial) and OS or progression to MM.
The findings of this study provide population-based estimates of the incidence, prevalence and prognosis for patients with SPB of the spine. This analysis indicated that the only identifiable prognostic indicators were older age and surgery without radiotherapy. Moreover, the methods of surgical resection did not influence the OS or progression to MM.
Level of Evidence: 4
∗Department of Orthopedic Surgery, Second Affiliated Hospital, Harbin Medical University, Harbin, China
†Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada.
Address correspondence and reprint requests to Jinglong Yan, MD, Department of Orthopedic Surgery, Second Affiliated Hospital, Harbin Medical University, No. 246 Baojian Road, 150086 Harbin, China; E-mail: firstname.lastname@example.org
Received 26 April, 2018
Revised 7 June, 2018
Accepted 11 June, 2018
YW and HL contributed equally in this work.
The manuscript submitted does not contain information about medical device(s)/drug(s).
The Fund of HMU-2nd Affiliated Hospital for Outstanding Young Scholars funds were received in support of this work.
No relevant financial activities outside the submitted work.
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