Rare cancer patients still have limited access to personalised care in Europe

Whereas the growing adoption of clinical practice guidelines is helping to harmonise knowledge and expertise on rare cancers across Europe, a critical gap remains between precision oncology and real-world access to high-quality cancer treatments. Only about one in five patients with advanced rare cancers was able to access treatment matched through individual molecular profiling, according to the sobering reality highlighted by the final results of the ARCAGEN study, presented at the ESMO Sarcoma and Rare Cancer Congress 2026 in March (81MO).

In the European Organisation for Research and Treatment of Cancer (EORTC)-SPECTA and EURACAN study, a high prevalence of molecular alterations across different rare solid tumours was observed among the 839 patients evaluated for molecular profiling (F1LCDx panel). Of these, 656 patients harboured clinically relevant alterations, and 620 had clinically actionable alterations. The proportions observed were similar to those found in more common malignancies, and no significant differences in molecular alterations were reported between tissue and liquid biopsy samples.

Among patients with actionable alterations, 15% received appropriately matched targeted therapy or immunotherapy, with discrepancies observed across different tumour types. A larger proportion of patients with thyroid and adrenal gland tumours and neuroendocrine tumours (NETs) accessed individualised care, whereas none of those with rare thoracic cancers did so, despite having recommendations.

While the implementation of molecularly-guided treatment recommendations was limited, favourable outcomes were observed in patients who received matched care. Median overall survival (OS), calculated from the start of first-line treatment to death or last follow-up, was 1.1 years (95% CI = 0.9-1.3). This increased to 3.3 years among patients who received targeted therapy following study recommendations (95% CI = 1.7-4.9). For those treated with immunotherapy based on study recommendations (n=17), the median OS was not reached.

The study highlights a critical gap in rare cancer care, also emphasising that while recommendations for clinical trial inclusion exist, actual patient enrollment is extremely limited. Out of 304 patients recommended for clinical trials, only 6 were enrolled, underscoring the urgent need for strategies to improve access to both specialised care and clinical research opportunities.