The 31-gene expression profile test stratifies melanoma-specific survival across histological subtypes in patients with cutaneous melanoma

Abstract

Introduction: Cutaneous melanoma (CM) histopathological subtypes, although not part of staging, differ in frequency and prognosis.  Superficial spreading tumors (~70% of CM) generally have good outcomes, while nodular melanomas (~15%) are aggressive and have the highest mortality rate.  However, certain patients with lower-risk subtypes are at higher risk of death from CM, while some patients with higher-risk subtypes are at low risk of death.  Tools to identify high- and low-risk patients, regardless of tumor subtype, are critical for personalized patient care.  The 31-gene expression profile identifies patients at low (Class 1A), intermediate (Class 1B/2A), or high (Class 2B) risk of dying from their disease.  

Methods: We assessed melanoma-specific survival (MSS) stratification by the 31-GEP among tumor subtypes.  SEER registry data (2013-2019) were linked to patients with CM who had 31-GEP results (n=13,560). Five-year MSS was estimated using Kaplan-Meier analysis and compared using the log-rank test. 

Results: The 31-GEP (Class 1A vs. Class 1B/2A vs. Class 2B) significantly stratified 5-year MSS among patients with: (1) superficial spreading tumors (n=4650, 99.0%; 93.8%; vs. 86.6%; p<0.001), (2) lentigo maligna melanoma (n=1306, 98.6%; 94.9%; vs. 87.7%; p<0.001), (3) nodular melanoma (n=1047, 98.5%; 86.4%; vs. 82.3%. p<0.001), and (4) no specified subtype (n=6192, 98.4%; 93.8%; vs. 86.8%; p<0.001), .  Desmoplastic (n=198), spitzoid (n=142), and acral (n=94) subtypes had <10 MSS events each; therefore, survival analysis was not feasible. 

Conclusions: Regardless of subtype, the personalized risk stratification by the 31-GEP provides more clarity in overall risk, allowing clinicians and patients to make better management decisions, improving patient care and outcomes.