New Peer-Reviewed Study Validates Melaseq™ Prognostic microRNA Test for Early-Stage Melanoma

GENESEQ BIOSCIENCES   |   Melbourne, Australia   |   www.geneseq.com.au 

Melbourne, Australia - 17 March 2026. Geneseq Biosciences today announced the publication of a peer-reviewed study in European Journal of Cancer: Skin Cancer validating the prognostic performance of its MEL12 microRNA signature in early-stage melanoma. The study demonstrates that Melaseq™ prognostic testing can identify patients at significantly higher risk of melanoma-specific death using the same formalin-fixed tissue collected during routine diagnosis.

Early-stage melanoma (Stage I-II) accounts for approximately 80% of the 17,000 new diagnoses each year in Australia. While most patients have excellent outcomes, a clinically significant minority develop metastatic disease that current staging methods may not reliably predict. Critically, metastatic melanoma can present many years after initial diagnosis, making long-term prognostic information essential. The MEL12 signature addresses this gap by providing a genomic risk score from the diagnostic biopsy specimen, offering long-term prognostic insight from a single test at the time of diagnosis.

Understanding the Clinical Need: A Patient Story

The following hypothetical case illustrates the type of clinical scenario that Melaseq prognostic testing is designed to address. It reflects real patterns of melanoma recurrence documented in the published literature, and the clinical outcomes data from the MEL12 study.

PATIENT STORY: A CASE FOR EARLY PROGNOSTIC TESTING

Mark, 52, Construction Manager — Melbourne, Australia (Hypothetical)

In 2019, Mark noticed a small dark spot on his upper back. His GP referred him to a dermatologist, who removed the lesion under local anaesthetic. The pathology report was reassuring: a Stage I melanoma, 0.9 mm in Breslow thickness, with clear margins. His surgeon explained that it had been caught early and was very likely cured by excision alone.

Mark completed his recommended annual skin checks. No further melanoma was detected. He returned to work, to his family, and to the assumption that the chapter was closed.

In late 2023 - four years after his original diagnosis - Mark developed persistent lower back pain. Imaging revealed multiple lesions in his liver and lungs. A biopsy confirmed metastatic melanoma, originating from the 2019 primary tumour. Despite modern immunotherapy, his disease progressed rapidly. He passed away eighteen months later.

What if Melaseq had been available in 2019?

At the time of Mark's original biopsy, his tumour would have been eligible for Melaseq prognostic testing. The preserved formalin-fixed tissue - already removed as part of standard diagnosis - would be sufficient. Had the MEL12 microRNA signature been applied, his genomic risk score may have placed him in the genomic high-risk category: a group in the published study in which patients experienced melanoma-specific death at a rate 8 to 10 times higher than those classified as standard risk, across up to 15 years of follow-up.

A high-risk result would not mean that metastasis was inevitable. It would mean that the tumour carried molecular characteristics associated with a substantially increased likelihood of future spread - characteristics invisible to conventional staging but detectable in its microRNA profile.

This information, available at the time of Mark's original diagnosis, might have prompted a different clinical path:

• More frequent imaging surveillance - for example, 6-monthly CT or whole-body PET scans in addition to annual skin checks.
• Sentinel lymph node biopsy to detect microscopic nodal spread before it became clinically apparent.
• Earlier referral for consideration of adjuvant immunotherapy, which is approved for high-risk Stage II melanoma and has demonstrated significant reductions in recurrence in clinical trials.
• A structured long-term monitoring plan, acknowledging that late recurrence beyond three years is a recognised - and often under-anticipated - feature of melanoma biology.

Metastatic melanoma detected at a regional nodal stage is far more amenable to treatment than disease that has spread to visceral organs. In Mark's case, the window for potentially curative intervention may have remained open for years after his initial surgery. A genomic signal present in the 2019 biopsy tissue - detectable with tools now available - might have been the key to identifying that window before it closed.

This narrative is a hypothetical illustrative example based on published clinical data and recognised patterns of melanoma recurrence. Individual outcomes vary. The Melaseq Prognostic Risk Score is not yet approved for routine clinical use and is subject to ongoing regulatory review.

Key Study Findings

The study analysed melanoma skin biopsies from 277 Stage I-II melanoma patients with up to 15 years of survival follow-up, one of the longest observation periods reported for a molecular prognostic study in early melanoma.

a)         Prognostic accuracy: C-index 0.82 (training) and 0.79 (independent validation) for melanoma-specific survival.

b)         Risk separation: High-risk lesions were associated with 8-10× the rate of melanoma death compared to standard-risk lesions (p < 0.001; Figure 1A).

c)         Continuous risk: Lowest scores: >99% five-year survival; highest scores: <30% (Figure 1B).

d)         Independent of clinical factors: Significant after adjustment for Breslow thickness, AJCC stage, subtype, age, and sex.

e)         Platform neutral: Equivalent performance across NanoString and RNA-seq (p = 0.373 for interaction).

Figure 1. (A) Kaplan-Meier survival by MEL12 risk group, independent test set. (B) Predicted 5-year survival vs. continuous MEL12 score with 95% CI. Dashed line: predefined risk threshold.

Clinical Significance

The MEL12 signature was originally discovered in circulating plasma and has now been validated in skin biopsy tissue, demonstrating that diagnostic and prognostic microRNA testing can be performed from a single tissue sample. The study's 15-year follow-up is particularly important given melanoma's unpredictable recurrence pattern. A prognostic test validated over this timeframe provides patients and clinicians with long-term confidence: meaningful reassurance for standard-risk patients and timely access to intensified monitoring and adjuvant therapy for those at elevated risk.

Clinical applications include:

• Guiding sentinel lymph node biopsy decisions
• Informing surveillance intensity and follow-up frequency
• Identifying candidates for adjuvant immunotherapy
• Providing personalised prognostic information from a single biopsy at diagnosis

Regulatory Pathway

The Melaseq™ Diagnostic Score (MEL38) is NATA-accredited for clinical use as a diagnostic aid for invasive cutaneous melanoma. Geneseq intends to seek regulatory approval for the Melaseq Prognostic Risk Score (MEL12 prognostic algorithm). Clinical availability is subject to completion of the regulatory review process.

Comment

"With up to 15 years of patient follow-up, this study provides a level of long-term prognostic validation that is rare in molecular diagnostics. The ability to extract both diagnostic and prognostic information from a single tissue sample positions Melaseq as a comprehensive molecular assessment tool for melanoma, offering patients and clinicians long-term confidence from a test performed at the time of diagnosis."

- Dr Ryan Van Laar, CEO and Founder, Geneseq Biosciences

About Geneseq Biosciences

Geneseq Biosciences is a Melbourne-based molecular diagnostics company developing microRNA-based liquid biopsy and tissue tests for cancer detection and risk stratification. Its Melaseq™ platform is NATA-accredited and operates through a commercial partnership with Australian Clinical Labs.

Media Contact: Dr Ryan Van Laar, Geneseq Biosciences | ryan.vanlaar@geneseq.com.au | +61 3 9028 2992

Citation: Van Laar R, et al. Validation of a Prognostic microRNA Signature in Early-Stage Melanoma Across NanoString and RNA-Sequencing Platforms. EJC: Skin Cancer. 2026. [In Press]

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