Survival benefit and clinical characteristics of patients with metastatic colorectal cancer (mCRC) receiving pulmonary metastasectomy.

59 Background: The role of lung metastasectomy in mCRC remains a topic of particular controversy, being uncertain which patients benefit more from it and whether it leads to better survival outcomes. Our aim was to identify clinical and molecular differences and survival data in a cohort from a tertiary care hospital. Methods: We retrospectively analyzed 115 patients with lung metastases from colorectal cancer (CRC) in a tumor registry from 2015 to 2021, analyzing clinical and molecular characteristics, as well as overall survival (OS) data of patients who received lung metastasectomy versus patients who did not. Results: Among all patients, 36 (31.3%) received pulmonary metastases surgery. Patients undergoing metastases resection had more frequently ECOG 0 (51.4% vs 20.8%, p = 0.0011), resected primary tumor (100% vs 78.5%, p = 0.0026), metachronous metastatic disease (75% vs 46.8%, p = 0.0048) and a single metastatic location (79.4% vs 41%, p = 0.0002). In addition, none of them had BRAF mutation (0% vs 17.1%, p = 0.04); however, no statistically significant differences were found regarding KRAS, NRAS, PI3K, HER2 or presence of microsatellite instability (MSI). Patients who received lung metastasectomy had higher BMI (26.1 vs 24.4, p = 0.037) and lower mean levels of CEA (19.5 vs 142.9, p = 0.007), CA 19.9 (30.6 vs 244.9, p = 0.011) and LDH (159 vs 211.9, p = 0.018). We found an OS benefit in patients undergoing metastatic surgery (median not reached (NR) vs 41.4 months, HR for death 0.27, 95% CI, 0.14 - 0.53, p < 0.000); a multivariate analysis confirmed that this benefit was independent from the characteristics mentioned above. The median progression-free survival (PFS) after metastases resection was 53.3 months. Conclusions: In our study, patients who were more likely to receive lung metastasectomy were those with ECOG 0, resected primary tumor, metachronous disseminated disease, a single metastatic location, native BRAF mutation status and low CEA, CA 19.9 and LDH levels, with a significant OS benefit associated.