Neoadjuvant chemotherapy followed by liver resection for patients with metastatic colorectal cancer.

Abstract

147 Background: Colorectal cancer is one of the leading causes of cancer related deaths with liver being most common site of CRC metastasis. More than 50% of the CRC patients will develop metastatic liver lesion that eventually leads to death in about 70% of them. In this retrospective review we reviewed the outcome of pts who received neoadjuvant chemotherapy followed by resection of liver lesion for metastatic colorectal cancer. Methods: 304 pts who had preoperative chemotherapy were identified from 1045 metastatic colorectal cancer patients who had liver metastasectomy at Mayo Clinic between 1997 and 2018. A retrospective review was conducted by using data from electronic medical records. Statistical analyses utilized Kaplan-Meier method, Log-rank test, and Cox proportional hazards models. Results: There were 113 (37%) female and 191 (63%) male pts. Median age at primary disease diagnosis was 56.5 yrs. Two hundred forty-nine pts presented with stage IV metastatic colorectal cancer. Primary tumor locations were: 53 right-sided, 117 left-sided and 133 rectum. 152 (50%) pts had extrahepatic metastases. Two pts were found to be MSI-H, 113 MSS, 189 unknown. BRAF mutation was found in 6 patients. RAS mutation was present in 84 patients, with 124 unknown. Pts received chemotherapy for median of 2.82 months. Single agent fluoropyrimidine was administered in 38 (12%) pts and rest receiving chemotherapy doublet or triplet with fluropyrimidine plus oxaliplatin being most common regimen. The median overall survival from primary diagnosis for the entire group was 74.5 months. Median overall survival from liver metastasectomy was 60.0 months. In univariate analysis, metachronous disease, age < 60 yrs, and an absence of extrahepatic lesions led to statistically significant improvement of overall survival from primary diagnosis. Metachronous and extrahepatic lesions remained statistically significant in multivariate analysis. Conclusions: Neoadjuvant chemotherapy followed by liver metastasectomy is beneficial for highly-selected metastatic colorectal cancer pts. Compared to a historical control of 30-36 months, our patient population had a median overall survival of about 5 years from resection.