Preliminary Analysis of Liquid Biopsy after Hepatectomy for Colorectal Liver Metastases.

ABSTRACT Background Liquid biopsies are increasingly tested in patients with colorectal cancer to assess tumor burden, response to therapy, and prognosis. The significance of liquid biopsy results after resection of colorectal liver metastases (CLM) is not well-defined. Study Design Sixty-three patients undergoing CLM resection between 2016−2018 had plasma drawn postoperatively for liquid biopsy evaluation. Next-generation sequencing analysis was performed to detect somatic mutations in 70 genes. Results Liquid biopsy after CLM resection was positive in 42 of 63 patients (67%). Eleven patients (18%) had 1 gene mutation, 14 (22%) had 2−3 mutations, and 17 (27%) had ≥ 4 mutations. The most common mutation was APC, detected in 32 (76%) patients, followed by TP53 (74%) and KRAS (38%). Two-year OS from date of liver resection was significantly worse among patients with a positive liquid biopsy (70% versus 100%, p = 0.005), particularly for those with ≥ 4 gene mutations detected, whose 2-year OS was 41%. Sixteen of the 63 patients underwent serial liquid biopsies, resulting in 100 liquid biopsy with matched serum CEA and computed tomography (CT) scan results. Metastases were identified in 74 CT scans, which correlated with positive liquid biopsy in 77% of samples (p 3 ng/ml in 45% of samples (p Conclusion Liquid biopsy results provide complementary information to serum CEA and CT imaging about disease burden and prognosis. A positive liquid biopsy after CLM resection is associated with worse OS, particularly when multiple gene mutations are detected.