Establishing an evidence-based decision point for clinical use of the 31-gene expression profile test in cutaneous melanoma

Abstract

Treatment plans for cutaneous melanoma are based upon individual risk of recurrence. Decisions made post-diagnosis include recommendation for a sentinel lymph node biopsy (SLNB), followed by management decisions such as surveillance, frequency of follow-up, and interdisciplinary consultations including possible adjuvant therapy use. These have traditionally been guided by clinicopathologic factors, but discordance exists, as a substantial number of melanoma deaths occur in patients diagnosed with disease considered to be early stage by such factors, including a negative SLNB. Molecular testing can be used to apply an objective approach that optimizes individualized patient care. The 31-gene expression profile (31-GEP) test has been validated in nearly 1600 patients as an independent predictor of risk of recurrence, distant metastasis and death in Stage I-III melanoma and can guide SLNB decisions in patient subgroups, as demonstrated in 1421 patients. While clinical use of the 31-GEP test has been adopted into routine practice, an evidence-based analysis of a decision point for use in thin, T1 tumors would be clinically useful. To help define an appropriate population for 31-GEP testing, we evaluated changes in patient management, cumulative differential risk across Breslow thicknesses based on a large dataset, and 31-GEP subclass distribution in a clinically tested cohort. Based on this, appropriate use of the 31-GEP test for management decisions was found to be in cutaneous melanoma tumors ≥0.3 mm thick.

Assessment of the 31-Gene Expression Profile Test by Dermatologists: A Cross-Sectional Survey from National Dermatology Conferences

“…Prior studies have validated its ability to determine the risk of local/distant recurrence and sentinel lymph node positivity to assist in clinical decisionmaking. [1][2][3] The 31-GEP test is reimbursable under Medicare, certified by the Clinical Laboratory Improvement Amendments (CLIA), and was ordered over 16,000 times during 2019. 1,4 Given the increasingly widespread use of 31-GEP, the purpose of this study was to assess the professional understanding, opinions, and clinical usage of the 31-GEP test by dermatologists.…”

Gene Expression Profile Testing for Thin Melanoma

“…6 These recommendations include use of 31-GEP in any patient with melanoma with negative SLNB, as well as patients with T1 tumors (including tumors with a depth Յ0.3 mm with adverse features) for SLNB decision guidance. 6,9 A recent study surveyed 181 dermatology clinicians (approximately 50% dermatologists practicing for more than 20 years) and found that 22% of clinicians would order 31-GEP testing on nonulcerated melanomas with a Breslow depth of 0.26 mm, and 78% would order testing on tumors with a depth of 0.50 mm. 4 Neither NCCN nor American Academy of Dermatology guidelines include 31-GEP testing as part of routine care for any melanoma.…”

“…However, publications have encouraged changes in diagnostic and management protocols based on 31-GEP testing results . These recommendations include use of 31-GEP in any patient with melanoma with negative SLNB, as well as patients with T1 tumors (including tumors with a depth ≤0.3 mm with adverse features) for SLNB decision guidance . A recent study surveyed 181 dermatology clinicians (approximately 50% dermatologists practicing for more than 20 years) and found that 22% of clinicians would order 31-GEP testing on nonulcerated melanomas with a Breslow depth of 0.26 mm, and 78% would order testing on tumors with a depth of 0.50 mm .…”