Incorporating precision oncology in everyday clinical practice: First two years of comprehensive genomic profiling (CGP) testing experience in Croatia.

11151 Background: Despite increased availability of modern technologies and evolution of tailored treatment, which has already significantly changed the outcomes in some cancer types, applicability of precision medicine in everyday clinical practice is still emerging and is one of the hot topics. Croatia is among first ones in the World to have entered into force a country-level based project of precision oncology throughout the CGP analysis in everyday clinical work, fully covered by Croatian health insurance. Hence, here we would like to present our data from everyday clinical practice and analyze the penetration of CGP given the opportunity and challenges we had. Methods: The study was observational and retrospective in nature, conducted on a country level among all patients on whose tumor specimens CGP was performed between January 1, 2020 and December 31, 2021. Eligible patients for the CGP analysis were those with metastatic disease, with at least 6-12 months of life-expectancy, with ECOG performance status ≤ 2, and after the recommendation from the multidisciplinary team. The analysis was performed in accredited laboratory (Foundation Medicine Inc., Cambridge, MA, USA), through FoundationOneCDx for solid tumors, FoundationOne Liquid in case of insufficient tissue or FoundationOneHeme for sarcomas. Results: There was total of 481 patients with CGP results. Median age was 61 years (IQR 49-69) and 58% of patients were women, while 42% were men. Most commonly tested were gastrointestinal (29.1%) and reproductive tumors (28.9%) with colorectal (19.1%) and uterine cancer (11.2%) as the most prevalent. At least one clinically relevant genomic alteration was found in 48.7% of patients. The most frequent mutations were those of KRAS (27.2%), PIK3CA (12.9%), AR (10.6%), NRAS (10.4%) and PTEN (9.1%) genes. Currently clinically not relevant mutations were found in 51.8% of patients with TP53 gene mutation as the most common (42.8%). According to the Croatian cancer registry, there was around 26 000 cancer related deaths during the investigated period defining population of at least more than 10 000 potentially eligible patients for the CGP analysis. Conclusions: Our results have shown that almost 50% of tested patients could have potential treatment benefit based on the detection of clinically relevant genomic alteration. Unfortunately, taking into consideration country level insurance eligibility criteria for CGP testing and number of potentially eligible cancer patients, we could say that only less than 5% of patients with metastatic disease were tested within first two years and that penetration of CGP is rather low, resulting with a significant number of patients underserved.