Final results of ARCAGEN – An EORTC-SPECTA and EURACAN initiative for molecular profiling and access to treatment for rare cancers

A new study published in Nature Communication has demonstrated the value of comprehensive molecular profiling in helping identify personalised treatment opportunities for patients with rare cancers across Europe.

Conducted through the EORTC SPECTA Arcagen study in partnership with EURACAN, the research evaluated the feasibility and clinical impact of genomic profiling in a real-world setting. Rare cancers collectively account for around 22% of all cancer diagnoses in Europe and more than 30% of cancer-related deaths, yet patients often face barriers to expert diagnosis, molecular testing, and access to innovative treatment options.

Between July 2020 and January 2023, the study enrolled 1,235 patients with advanced rare cancers across 13 European countries, of whom 893 were evaluable for molecular profiling. Across 11 rare cancer domains, researchers found that 69.4% of patients (620/893) had actionable molecular alterations that could potentially guide treatment decisions.

Among these patients, 93 received targeted therapies or immunotherapies based on their molecular profile. Patients whose treatment was adapted following molecular analysis showed encouraging outcomes, with a median overall survival of 3.3 years for those receiving targeted therapies, compared with 1.1 years for those without treatment adaptation. Median overall survival had not yet been reached for patients treated with immunotherapy.

The study also demonstrated that large-scale molecular profiling can be successfully implemented across Europe. Both tumour tissue and circulating tumour DNA analyses provided valuable insights, helping identify clinically relevant alterations even when tissue samples were limited. Importantly, molecular reports were delivered within a median of 14 days for tissue-based analyses and 12.5 days for blood-based testing following sample receipt.

The researchers conclude that comprehensive molecular profiling can help unlock personalised treatment options for many rare cancer patients while highlighting persistent disparities in access to precision medicine across Europe. The findings support broader efforts to integrate molecular testing into routine care and improve access to targeted therapies for rare cancer patients.

DOI: https://doi.org/10.1038/s41467-026-75776-1

Arcagen is a #SPECTAplatform downstream project. The SPECTA Platform is supported by Alliance Healthcare. Alliance Healthcare will become Cencora. Arcagen is a collaboration between EORTC and Euracan and is funded by F. Hoffman-La Roche.