Gene Profile Test May Improve Risk Stratification in Cutaneous Melanoma

The 31-gene expression profile test, DecisionDx-Melanoma, demonstrated improved risk stratification over American Joint Committee on Cancer (AJCC) staging alone in patients with stage I cutaneous melanoma, according to a press release from Castle Biosciences, Inc.¹

"As the study showed, [the 31-gene expression profile test] provides more precise risk stratification over staging alone to better predict which patients have a low risk of experiencing a poor outcome and those with more aggressive tumor biology who may benefit from increased clinical surveillance,” according to an expert from Hospital Clinic of Barcelona, Spain.

Findings from a poster presented at the 19th European Association of Dermato-Oncology (EADO) Congress in Rome, Italy, highlighted an estimated 5-year relapse-free survival (RFS) rate of 93.3% (95% CI, 93.1%-94.7%) in those with low-risk stage IA disease and 87.6% (95% CI, 85.4%-89.9%) in those with high-risk stage IB disease with AJCC staging.² For the 31-gene expression profile test, the estimated RFS rates were 97.3% (95% CI, 96.1%-98.5%) in those with low-risk class 1A disease, 88.6% (95% CI, 83.6%-93.7%) for class 1B/2A disease, and 77.3% (95% CI, 66.9%-89.2%) in those with high-risk class 2B disease.

With risk-stratification via AJCC staging, the estimated melanoma-specific survival (MSS) rates were 97.6% (95% CI, 96.2%-99.0%) in those with stage IA disease and 97.9% (95% CI, 95.9%-99.9%) in those with stage IB disease. The 31-gene expression profile test provided MSS estimates of 98.0% (95% CI, 96.7%-99.2%) in those with class 1A disease and 92.3% (95% CI, 86.2%-98.8%) in those with class 2B disease.

Investigators concluded that the 31-gene expression profile test may add “valuable” prognostic information to AJCC criteria, effectively stratifying RFS and MSS in those with cutaneous melanoma. In the study, patients with AJCC stage I cutaneous melanoma who had a high-risk or class 2B result with 31-gene expression profile testing were 7.6 times more likely to die from melanoma compared to those with Class 1A disease, and 5.4 times more likely relative to stage 1B disease.

Additionally, findings suggested that incorporating the gene expression profile test into clinical practice may inform better risk-aligned care in patients considered low risk by identifying high-risk disease that may have been missed with the sole use of AJCC staging.

“As the study showed, [the 31-gene expression profile test] provides more precise risk stratification over staging alone to better predict which patients have a low risk of experiencing a poor outcome and those with more aggressive tumor biology who may benefit from increased clinical surveillance,” lead study author Sebastian Podlipnik, MD, a board-certified dermatologist in the Department of Dermatology at Hospital Clinic of Barcelona, Spain, said in the press release.

The 31-gene expression profile test was designed to help determine a patient’s individual risk of sentinel lymph node positivity and personal risk of melanoma recurrence and/or metastasis. The test integrates tumor biology with clinical and pathologic factors to provide a clinically actionable result to guide risk-aligned care for patients. According to manufacturers, the test has been shown to correlate with improved patient survival in studies including more than 10,000 patient samples.

Investigators of the study presented at the EADO Congress aimed to demonstrate the added value of the 31-gene expression profile test to stratify recurrence risks and melanoma-specific death in patients with stage I cutaneous melanoma compared with the use of AJCC criteria on its own. The study included 1261 patients tested with the 31-gene expression profile who enrolled in previous prospective and retrospective studies.

Additionally, investigators included data from 5651 patients tested with the 31-gene expression profile found in the Surveillance, Epidemiology, and End Results registries.

References

1. DecisionDx®-Melanoma provides improved risk stratification over American Joint Committee on Cancer (AJCC) staging alone in stage I melanoma patients. News release. Castle Biosciences, Inc. April 25, 2023. Accessed April 26, 2023. bit.ly/41W9bVC
2. Podlipnik S, Petkov VI, Byun JS, et al. The 31-gene expression profile outperforms AJCC in stratifying risk of recurrence in patients with stage I cutaneous melanoma. Presented at: 19th European Association of Dermato-Oncology (EADO) Congress; April 20-22, 2023; Rome, Italy.