Insufficient Representation and Reporting of Race in the References Forming the Basis of the National Comprehensive Cancer Network Guidelines for Multiple Myeloma

Background: While Black individuals currently represent 13.6% of the U.S. population, they represent roughly 20% of newly diagnosed multiple myeloma (MM) cases, owing to a 2-fold increased incidence compared to the White population (Giaquinto A et al.CA Cancer J Clin,2022). Practitioners rely on guidelines set by the National Comprehensive Cancer Network (NCCN) for the diagnosis and treatment of MM, so it is essential that these guidelines are based on data from representative populations. An earlier review of the International Myeloma Working Group guidelines showed a lack of racial diversity in the supporting studies (Fahmawi S. et al. J Ca Policy,2023). Considering the wide usage of the NCCN guidelines we conducted a review of the racial demographics in the references used to construct the NCCN-MM guidelines.

Methods: We conducted a review of the references used to inform the NCCN MM Guidelines Version 4.2024. Five reviewers analyzed 283 cited references. The subset of references used in our assessment of representation included original English language publications describing the results of MM clinical studies, regardless of where the study was conducted geographically. We excluded review articles, non-clinical studies, commentaries, editorials, case reports, abstracts, animal-based studies, and studies that were not specific to MM. Additionally, we excluded any references which reported on the same clinical study as another reference. For each of the included references, reporting on minority representation was assessed.

Results: 283 references were reviewed and 87 were excluded based on the predetermined criteria above. The remaining 194 studies were assessed to determine the reporting and composition of race. Fifty-one studies (26.3%) reported racial demographics, however only 39 of these (20.1%) reported the number of Black patients in the studies. In 12 of the studies that disclosed race, authors reported the White proportion of their study population but made no mention of the number of Black participants. Of the 39 studies that could be analyzed, 8.6% of the participants were black as compared to 78.6% of White participants. Data was then assessed in sequential time blocks to assess race reporting over time. From 1980-1999 seven studies were included, however none of these included racial demographics. In 2000-2004,1/10 studies reported race data (10%), compared to 3/30 studies (10%) between 2005-2009, 11/45 studies (24.4%) between 2010-2014, 21/61 (34.4%) between 2015-2019, and 18/50 (36%) between 2020-2023. Of trials conducted only in the United States 21/60 (35%) trials in included racial demographics. For international studies, only 23.7% included racial demographics.

Conclusion: Out of 194 studies reviewed, reporting of race was only reported in 26.7% of studies with an inclusion of only 8.6% Black participants. While race reporting appears to increase overtime, with 35% of studies published within the last 4 years including demographics, it should be a standard requirement. Despite the increase in reporting, the percentage of Black patients used to form NCCN treatment guidelines is not representative of the rates of MM within the US Black community. Racial and ethnic diversity within research is essential to ensure findings are applicable to real-world patients. Based on our findings, we call on investigators and guideline committees to standardize race reporting when considering studies in guideline recommendations. We propose that clinical trials published after 2024 should only be cited in future NCCN guidelines if demographic information regarding race and ethnicity is reported. We would call upon the MM research community to make clinical trials diverse to allow the results (and subsequent guidelines) to be relevant to everyone.