Abstract
Background: SEER Data from 1975-2008 show a stark disparity in the incidence of multiple myeloma (MM) in African Americans (AA) compared to Caucasians, with a 2-3 times higher incidence in AA. Differences in the incidence appear to be genetically driven, but remain poorly understood. Although AA patients appear to have a lower incidence of high risk cytogenetics [Greenberg G et al, Blood Cancer J 2015], their outcomes have not improved in the novel era therapy compared to Caucasian patients [Ailawahdi S et al, Blood Cancer J 2016]. Access to specialized disease-specific care (including access to a transplant center) due to socioeconomic status and lack of social support have been proposed as impediments to optimal care for AA MM patients. We prospectively examined newly diagnosed transplant eligible AA and Caucasian patients with MM at our institution to assess their transplant outcomes.
Methods: The MM database was interrogated from March 2014-December 2015 for all autologous stem cell transplant (ASCT) eligible patients with MM. Clinical features, induction regimens, treatment responses and ASCT outcomes were compared between AA and Caucasian patients. Continuous variables were compared using nonparametric rank tests, while incidences and proportions were compared using Fisher's exact tests.
Results: A total of 73 consecutive ASCT eligible MM patients were identified (32 AA, 41 Caucasian). There was no significant difference in sex distribution between the cohorts (p > 0.999). However, AA patients were significantly younger at the time of diagnosis with a median age of 56 years compared to a median age of 61 years in the Caucasian cohort (p = 0.008). Except for lower hemoglobin levels among AA patients, there were no statistically significant differences in any other clinical variable at diagnosis (lab features, serum LDH levels, ISS staging, IMWG risk stratification, cytogenetics, etc.) between the patient cohorts. Analysis of pre- and post- ASCT data showed similar response rates to induction therapy and outcomes with no statistically significant differences observed in pre-ASCT and post-ASCT depth of response (assessed by IMWG criteria) or 1-year progression free survival between the two cohorts.
Conclusions: At our institution, AA patients with MM presented at a younger age than Caucasians. However, no significant differences in disease features were observed between the two groups at the time of initial presentation. A much higher proportion of AA MM patients (44%) underwent ASCT at our institution compared to other academic centers. Although longer follow-up is required, our data suggest that when AA patients with MM are provided similar access to care as Caucasian patients with MM, similar response rates to induction therapy and ASCT can be achieved.
Bhutani:Prothena: Research Funding; Bristol-Myers Squibb: Speakers Bureau; Takeda Oncology: Research Funding, Speakers Bureau; Onyx, an Amgen subsidiary: Speakers Bureau. Symanowski:Caris Life Sciences: Consultancy; Ra Pharma: Consultancy; Eli Lilly & Co: Consultancy; Endocyte: Consultancy. Avalos:Seattle Genetics: Membership on an entity's Board of Directors or advisory committees. Usmani:Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Pharmacyclics: Research Funding; Onyx: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Skyline: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Britsol-Myers Squibb: Consultancy, Research Funding; BioPharma: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Sanofi: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Millenium: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Array: Research Funding; Amgen: Consultancy, Research Funding, Speakers Bureau; Novartis: Speakers Bureau.
Author notes
Asterisk with author names denotes non-ASH members.
