New and noteworthy research from the medical literature landscape
Examining Outcomes Among Hispanic Patients With Multiple Myeloma
Hispanic and non-Hispanic Black patients with multiple myeloma ( MM ) more often present with disease at a younger age and with significant renal dysfunction . These factors contribute to poorer survival among all racial / ethnic groups , yet Hispanic patients may have higher overall survival ( OS ) due to increased use of frontline autologous hematopoietic cell transplantation ( AHCT ), according to a report published in Clinical Lymphoma , Myeloma & Leukemia .
“ With equal access to care , Hispanics [ with myeloma ] have a good prognosis .”
— Gurbakhash Kaur , MD
Gurbakhash Kaur , MD , from John Theurer Cancer Center in Hackensack , New Jersey , and coauthors conducted a retrospective analysis of patients with MM who were included in the Montefiore Medical Center Cancer Registry , the National Program of Cancer Registries , and the Surveillance , Epidemiology , and End Results ( SEER ) database . Self-reported race and ethnicity data coded in the electronic medical record were identified to stratify assessments of disease characteristics and outcomes . Data also were collected from the Connect MM Registry , a large prospective observational cohort study comprising patients with newly diagnosed MM from 250 centers across the U . S .
While the initial cohort for this analysis included 1,634 patients , a total of 939 patients were included in the final analysis after excluding cases of monoclonal gammopathy of unknown significance , solitary plasmacytomas , and smoldering MM , and after excluding patients with incomplete records .
The remaining patients were categorized based on their race and ethnicity :
• Hispanic ( n = 281 ; 30 %)
• non-Hispanic Black ( n = 489 ; 52 %)
• non-Hispanic white ( n = 169 ; 18 %)
Overall , the mean age at time of MM diagnosis was 65.6 years . The average age at diagnosis was significantly lower among Hispanic and non-Hispanic Black patients compared with non-Hispanic white patients ( 64.5 vs . 70.6 years , respectively ; p < 0.01 ). This finding was replicated in the Connect MM Registry ( p < 0.01 ).
The authors also reported that a higher proportion of non-Hispanic Black ( 35.3 %) and Hispanic ( 28.8 %) patients were diagnosed with MM before age 60 , compared with non-Hispanic white patients ( 16.5 %; p < 0.01 ).
In the SEER database , Hispanic patients had the second-highest MM incidence rate after non-Hispanic Black patients across all age groups between 40 and 80 years , they added .
A greater proportion of non-Hispanic Black ( 61.1 %) and Hispanic ( 56.4 %) patients presented with severe renal dysfunction compared with non-Hispanic white patients ( 48.8 %; p = 0.02 ). Hispanic and non-Hispanic Black patients also presented with a significantly higher mean lactate dehydrogenase levels at diagnosis ( p = 0.01 ). “ These observations indicate that Hispanics present with earlier / lesser-stage disease and similar cytogenetic risk compared to non-Hispanic white and non-Hispanic Black [ patients ],” the researchers wrote .
Treatment also differed significantly among racial groups : Non-Hispanic white patients more often received triplet-based induction therapy compared with Hispanic and non-Hispanic Black patients ( 49.5 % vs . 43.3 % vs . 34.5 %; respectively ; p = 0.02 ). More Hispanic patients underwent AHCT , compared with non-Hispanic Black and non-Hispanic white patients ( 59.4 % vs . 48.1 % and 36.6 %; p < 0.01 ).
While the median OS for the entire cohort was 78 months , the median OS was highest for Hispanic patients , at 110 months , compared with non-Hispanic white ( 69 months ) and non-Hispanic Black patients ( 65 months ). “ As expected , advanced [ disease ] risk classification , and a response less than [ very good partial response ( VGPR )/ complete response ( CR )] to induction therapy negatively affected survival in the univariate analysis ,” the investigators reported . Next , in a multivariate analysis , International Myeloma Working Group risk ( IMWG , hazard ratio [ HR ] = 1.9 ), response to first therapy line ( partial response , HR = 0.35 ; VGPR / CR , HR = 0.2 ), and use of AHCT ( HR = 0.57 ) were independently associated with mortality .
“ The recognition that with equal access to care Hispanics have a good prognosis is important for clinical practice ,” the authors concluded , but they also noted that the study ’ s implications are limited by its retrospective nature and missing data from patients ’ medical records , including data on cytogenetic abnormalities and treatments received .
Study authors report no relevant conflicts of interest .
Reference Kaur G , Mejia Saldarriaga M , Shah N , et al . Multiple myeloma in Hispanics : incidence , characteristics , survival , results of discovery , and validation using real-world and Connect MM registry data . Clin Lymphoma Myeloma Leuk . 2020 November 21 . [ Epub ahead of print ]
PERSPECTIVES
In this single-center retrospective dataset , with validation using a real-world prospective dataset and the SEER registry , Hispanic and non-Hispanic Black patients were found to have a higher incidence of MM , have a younger age at presentation , and were more likely to present with renal dysfunction at diagnosis . However , on multivariate analysis adjusting for key variables such as cytogenetic risk and frontline treatment modalities , the authors found conflicting results with respect to the impact of Hispanic ethnicity on OS .
Kaur et al . suggest that cost , access , and adherence to therapies might explain disparities in outcomes . However , this would not account for the inverse relationship seen with AHCT , where Hispanic patients were more likely to undergo transplantation . This , along with younger age at diagnosis , are likely the key drivers for superior OS for Hispanic patients on univariate analysis in this study .
The retrospective nature of this study is a limitation , especially as it can lead to inconsistent data collection . In this dataset , there was a high degree of missingness for items such as cytogenetic abnormalities and treatments received , making interpretation of these data more challenging . In addition , there are some key discrepancies that need to be resolved . For instance , translocation of chromosomes 4 and 14 [ t ( 4 ; 14 )] is seen in approximately 15 % of cases of newly diagnosed myeloma , and ranged from only 0 to 1.9 % in this dataset , which seems inaccurate . In addition , gain1q is a known high-risk cytogenetic abnormality and was not factored into this analysis .
In future studies , it would be interesting to explore if factors such as high-risk cytogenetic abnormalities are associated with outcomes in Hispanic patients , given that much of our understanding of high-risk disease comes from homogenous cohorts of non-Hispanic white patients .
Benjamin Derman , MD University of Chicago
32 ASH Clinical News March 2021