New ESMO Classification: How Biomarkers Help Guide Cancer Treatment

The European Society for Medical Oncology (ESMO) has updated its international framework for assessing molecular alterations in cancer. The new ESCAT version 2 helps physicians evaluate targeted treatment options and potential resistance on the basis of scientific evidence — an important development in personalized cancer care.

Modern tumor analyses can identify a wide range of genetic alterations. However, not every mutation is relevant to a treatment decision. Even when a medication specifically targets a particular alteration, this does not automatically mean that its effectiveness has been established for the cancer type in question.

To provide a systematic approach to evaluating these findings, ESMO developed the ESMO Scale for Clinical Actionability of Molecular Targets (ESCAT) in 2018. On October 22, 2026, the society published a substantially revised version of this framework.

What Is New in ESCAT Version 2?

The updated classification reflects the considerable advances in molecular diagnostics and available treatment options over recent years.

Three developments are particularly relevant:

• A more precise assessment of the evidence: In particular, the highest evidence tier now explicitly distinguishes how firmly the clinical benefit of a targeted treatment has been established for a specific molecular alteration.
• Consideration of tumor-agnostic therapies: Some molecular alterations occur across different cancer types. The updated framework sets out defined criteria for determining when evidence can be applied across tumor types.
• A systematic assessment of resistance: For the first time, the framework includes a separate classification for resistance biomarkers. This helps assess which molecular alterations may indicate a reduced response, or a lack of response, to specific medications.

The framework also provides a more differentiated assessment of data from prospective clinical trials and findings from routine clinical practice, known as real-world data.

Why Does This Matter for Patients?

Particularly in advanced or previously heavily treated cancers, molecular testing may provide additional information for treatment planning.

Methods such as next-generation sequencing (NGS) allow numerous genetic alterations in a tumor to be examined simultaneously. Under appropriate conditions, liquid biopsies can also identify therapeutically relevant tumor alterations through blood samples.

What matters most, however, is how the identified alterations may inform treatment decisions.

This is where ESCAT comes in. The classification helps assess molecular findings according to the available clinical evidence. It supports the selection of appropriate targeted therapies while also making clear where the benefit of a treatment has not yet been sufficiently established.

In complex disease courses, this provides an important basis for multidisciplinary treatment decisions. However, the classification does not replace individual medical assessment or consideration of previous treatments, potential side effects, and the patient’s overall health.

Precision Oncology–Based Treatment Planning at the Hallwang Clinic

The assessment of a tumor’s molecular characteristics is a central part of the treatment approach at the Hallwang Clinic. Using genetic tumor profiling, next-generation sequencing, and liquid biopsy, the oncology team investigates therapeutically relevant alterations and potential mechanisms of resistance.

These findings inform the development of individualized treatment strategies, which take into account established standard therapies as well as targeted medications and modern immunotherapies. In medically justified individual situations, off-label treatments may also be considered following a detailed discussion with the treating physician and informed consent. Such decisions are based on an individual assessment of the available scientific evidence and the patient’s clinical situation. Classifications such as ESCAT help assess the strength of that evidence; they do not, in themselves, provide a recommendation for a particular off-label treatment.

The continued development of ESCAT underlines a central principle of precision oncology: molecular data become valuable for individualized cancer treatment through careful, evidence-based interpretation.

Understanding Your Molecular Findings

Do you already have results from tumor sequencing or a liquid biopsy? Our medical team reviews your records in advance to assess which further diagnostic investigations and treatment options may be appropriate. A definitive recommendation is made following an in-person medical examination.

Scientific references: El Helali A, et al. The ESMO Scale for Clinical Actionability of Molecular Targets, version 2 (ESCAT v2): an evidence-based framework for ranking alterations as actionability and resistance biomarkers in precision oncology. Annals of Oncology 2026. DOI: 10.1016/j.annonc.2026.09.008 · ESMO press release dated October 22, 2026 · Mateo J, et al. A framework to rank genomic alterations as targets for cancer precision medicine: the ESMO Scale for Clinical Actionability of molecular Targets (ESCAT). Annals of Oncology 2018;29(9):1895–1902. DOI: 10.1093/annonc/mdy263.

Please note: This article provides general medical information and does not replace individual medical advice, diagnostic assessment, or treatment recommendations.