Long-term survivors (LTSs) population of metastatic colorectal cancer (mCRC): A Northern Italian comprehensive cancer center experience

e15590 Background: mCRC patients (pts) have a median survival of 13-24 months with a 5-year survival rate of about 1%. LTSs are defined as pts with survival greater than or equal to 36 months after diagnosis of mCRC. Mutational status, new treatments, and surgery resection advances led to improved survival outcomes. Methods: This is a single-center retrospective analysis of 106 consecutive CRC pts with synchronous or metachronous metastases diagnosed from the AUSL-IRCCS of Reggio Emilia Comprehensive Cancer Center between January 1 st , 2017, and November 30, 2019. Clinical and pathological characteristics of pts were obtained from clinical records. Long-term survivors were defined as pts with survival > 36 months. Results: Out of 106 mCRC, 33 (31.1%) were LTSs with a median survival of 53 months (range, 36-129 months). At the data cut-off of November 30, 2022, 24 (72.7%) were still alive. Among all, 18 (54.5%) were men, the median age was 65 years (47-83), and 14 (42.4%) had a right tumor primary site. Synchronous metastases were found in 20 (60.6%), while 13 (39.4%) developed metachronous metastases; the most frequent site of metastases was the liver (63.6%), peritoneum and lymph nodes (21.2%), respectively. Surgical resections and systemic treatment regimens based on fluorouracil, oxaliplatin, and/or irinotecan, cetuximab, bevacizumab, TAS-102, regorafenib, and others are listed in Table 1. Regarding biological status, 28 (84.8%) had an MSS, 18 (54.5%) RAS wild type, and 3 (9.1%) BRAF V600E mutated of which 2 (66.7%) underwent surgical resection of primary tumor and metastases, receiving up to 2 lines of systemic treatments. Conclusions: This study confirms that long-term survivors of mCRC pts are the results of intrinsic tumor biology, appropriate treatment timing including surgery, and the available pharmacological opportunities beyond chemotherapy. Further analysis including the role of liquid biopsy is under investigation to identify prognostic and predictive biomarkers in order to improve survival outcomes. [Table: see text]