Prospective standardized surveillance of early-stage melanoma on the basis of anatomical staging and molecular profiling: Study design and interim analysis.

Abstract

Gene expression profiling of cutaneous melanoma has become pervasive in clinical practice, with minimal independent, nonindustry-sponsored, data to guide implementation and influence practice patterns. We developed a scoring system on the basis of anatomic staging and molecular profiling to risk stratify patients into 4 categories for prospective surveillance. Patients with cutaneous melanoma were recruited from 2019 to 2023 for enrollment into the study. Inclusion criteria included pathologic stage IA-IIC and use of a commercialized 31-gene expression profile system. Patients were stratified into 1 or 4 surveillance groups: A1 (stage IA-IIA/gene expression profiling class 1), A2 (stage IA-IIA/gene expression profiling class 2), B1 (stage IIB-IIC/gene expression profiling class 1), and B2 (stage IIB-IIC/gene expression profiling class 2). The primary outcome measure is rate of asymptomatic imaging-detected recurrence. Interim analysis has been performed at median follow-up of 24 months. A total of 200 patients were enrolled. Mean age was 61.0 years (standard deviation, 14.6 years) and 55.5% of the population was male. Primary lesions were distributed between the head and neck (n = 40, 20%), trunk (n = 76, 38%), and extremity (n = 84, 42%). Median depth was 1.1 mm (range, 0.3-8.8 mm) and 14% had ulceration present. Stage distribution was as follows: IA (n = 82, 41.0%), IB (n = 71, 35.5%), IIA (n = 27, 13.5%), IIB (n = 16, 8.0%), and IIC (n = 4, 2.0%). Gene expression profiling classification was class 1 (n = 145, 72.5%) and class 2 (n = 55, 27.5%). This provided a distribution of 71.0% in A1, 19.5% in A2, 2.0% in B1, and 7.5% in B2. Recurrences have been detected in 16 patients (8.0%) including 12 local/regional (6.0%) and 4 distant (2.0%) recurrences. Recurrence rates by surveillance group are: A1 = 4.9%, A2 = 10.3%, B1 = 0%, and B2 = 33.3%. Recurrences were detected by surveillance imaging in 3 (1.5%), history and physical examination in 10 (5.0%), and symptoms in 3 patient (1.5%), respectively. Pragmatic implementation of a risk-stratified surveillance strategy has resulted in few instances of asymptomatic, imaging-detected recurrences among early-stage cutaneous melanoma patients at short-term follow-up benchmarks. Further follow-up is necessary to determine the validity of this approach.