Impact of a 31-gene Expression Profiling Test for Cutaneous Melanoma on Dermatologists’ Clinical Management Decisions

May 2017 | Volume 16 | Issue 5 | Original Article | 428 | Copyright © May 2017

Aaron S. Farberg MD,a Alex M. Glazer MD,b Richard White MS,c and Darrell S. Rigel MD MSd

aDepartment of Dermatology, Icahn School of Medicine at Mount Sinai, New York, NY bNational Society for Cutaneous Medicine, New York, NY cIris Interactive System, Cody, WY dDepartment of Dermatology, NYU School of Medicine, New York, NY

Figure 1


Progress has been made in the understanding of the molecular mechanisms of CMM, resulting in pioneering treatments and clinical trials based on gene-targeted therapies.9 This understanding has also led to the identification and clinical use of novel prognostic molecular markers to improve risk stratification and tailor more effective management strategies in CMM patients.5 While SLNBx is the most accurate independent prognostic parameter for patients with CMM,10, 11 positive SLN status only identifies one-third of CMM patients who expire from their tumor.12 Given that SLN positivity is less than 5% in thin melanomas,13 having additional molecular information to more precisely identify patients that do not appear to be at higher risk for metastasis but may, in fact, be so due to genetic factors, is clinically useful.14The validity of the 31-GEP test has been demonstrated in multiple studies, most recently in a comparison with the AJCC online risk calculator which showed that the test provided information that significantly augmented the better identification of high-risk early stage patients.3,5-8,14 In the current study, we evaluated the clinical impact of the test on CMM management decisions of dermatology resident physicians. When 31-GEP results were not provided, most respondents adhered to current NCCN management guidelines by using a BT of 1.0 mm as the inflection point to recommend SLNBx. Adding 31-GEP test information to the clinical characteristics of the patient vignettes and inflection-point scenarios led to significant, risk-appropriate changes in management decisions in SLNBx, imaging, and oncology referral. These results demonstrate that the 31-GEP test positively influenced clinical management and patient care, as clinicians incorporated the additional data to modify their clinical recommendations, and the findings are consistent with a recent study that demonstrated that 31-GEP results were clinically utilized in a risk-appropriate manner.14 Limitations of this study include that the patient vignettes may have also oversimplified typical patient presentations of disease. Additionally, this study included only dermatology resident physicians who may be more likely to adopt new clinical and technological data compared to dermatologists that were further in their careers. 


The NCCN and AJCC guidelines, coupled with the treating physician’s judgment and patient preference, have been designed to guide the management of CMM. Our results suggest that the information provided by the 31-GEP test had a significant and appropriate impact on management while remaining within the context of established guidelines. 


Drs. Farberg and Rigel served as consultants to Castle Biosciences Inc. Dr. Glazer participated in a research fellowship which was partially funded by Castle Biosciences Inc. Mr. White has no conflicts of interest to disclose.