Increased incidence of a second lymphoproliferative malignancy in patients with multiple myeloma--a SEER based study.
BACKGROUND
Improving therapies means longer survival for multiple myeloma (MM) patients. We hypothesized that these patients are at an increased risk for a secondary malignancy.


OBJECTIVE
(i) To investigate the epidemiology and site-specific risk of second primary cancers (SPCs) in patients with MM (ii) To investigate the factors affecting survival in MM patients with SPCs.


METHODS
This was a retrospective cohort study employing data available in the US Surveillance Epidemiology and End Results (SEER) database.


METHODS
Adult patients (>18 years) where MM was the first of two, or more primary cancers, such that the diagnosis of MM and the SPC was separated by at least 1 month.


RESULTS
The age-adjusted rate SPCs in MM was 0.22 per 100,000 (95% CI=0.05-2.1). The incidence of SPCs was higher in patients aged ≥70 years, men and blacks. Age, gender and race were significant predictors for the occurrence of SPCs in MM. The risk of solid malignancies was significantly decreased (SIR: 0.94, 95% CI=0.89-0.99), while that of lymphohematopoieitc (LAHM) malignancies increased in MM (SIR: 1.68, 95% CI= 1.46-1.92). 5-year relative survival among MM patients with SPCs was higher in blacks (54.6%, 95% CI=49.5-59.4) than whites (53.8%, 95% CI=51.3-56.3) or other races (49.9%, 95% CI=39.8-59.3). Multivariate analysis revealed that race, site of SPC and year of diagnosis were independent predictors of survival among MM patients with SPCs.


CONCLUSIONS
MM patients are at a higher risk of a second LAHM.
Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE, USA. schakra@unmc.edu
Subhankar
S
Chakraborty
Ralph J
RJ
Hauke
Neelima
N
Bonthu
Stefano R
SR
Tarantolo
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D007938:Leukemia / Q000453:epidemiology* / Q000208:ethnology; D008223:Lymphoma / Q000453:epidemiology* / Q000208:ethnology; D008297:Male; D008875:Middle Aged; D009101:Multiple Myeloma / Q000453:epidemiology* / Q000208:ethnology; D016609:Neoplasms, Second Primary / Q000453:epidemiology* / Q000208:ethnology; D012189:Retrospective Studies; D012306:Risk; D018426:SEER Program / Q000706:statistics & numerical data*; D012737:Sex Factors; D055815:Young Adult