The integrated 31-gene expression profile test identifies low-risk patients with cutaneous melanoma who can forego the SLNB procedure: results from a prospective, multicenter trial

AIMS: Prospectively confirm use of the integrated 31-gene expression profile test (i31-SLNB) in patients with cutaneous melanoma to predict sentinel lymph node biopsy (SLNB) positivity and assess recurrence rates in those considered low risk by i31-SLNB who did not have an SLNB. METHODS: Patients with T1-T4 tumors being considered for SLNB who received 31-gene expression profile (31-GEP) testing in the multi-center, prospective DECIDE study were included (n = 912). Kaplan-Meier analysis was used to estimate recurrence-free survival (RFS). RESULTS: Among 430 patients with T1-T4 tumors who had an SLNB, the positivity rate was 2.6% (3/114) in those with <5% i31-SLNB-predicted risk versus 21.4% (28/131) in those with >10% predicted risk. Among those with T1-T2a tumors who had an SLNB (n = 359), the positivity rate was 1.8% (2/111) in those with <5% predicted risk versus 16.7% (12/72) in those with >10% predicted risk. The 3-year RFS rate was 97.8% in patients with i31-SLNB <5% predicted risk. CONCLUSIONS: In this multi-center prospective study, the i31-SLNB accurately predicted SLN positivity, and patients who avoided SLNB based on i31-SLNB results had high RFS. Thus, the i31-SLNB identifies low-risk patients who may consider foregoing the SLNB procedure.