EARLY HEPATIC RECURRENCE AFTER COLORECTAL CANCER LIVER METASTASES SURGERY: A SINGLE PROSPECTIVE CENTRE STUDY

Liver resection, combined with modern chemotherapy, is considered the standard treatment for patients with resectable CRLM. However, the recurrence of hepatic metastasis after liver resection remains a concern worldwide. About twenty years ago, important studies overwhelmed the historical concept that 1.0-cm margin was not an absolute requirement for a curative approach in the treatment of patients with colorectal cancer liver metastases. This is a prospective observational study, performed at the Oncological Surgery, Hospital Policlinic San Martino, Genoa, Italy from 1st April 2014 to the 1st June 2019. Patients undergoing primary hepatic resection for colorectal liver metastasis with curative intent and having a minimum follow-up period of 6 months were included. Several clinical, pathological, and surgical factors have been tested for correlation with early recurrence and disease-free survival (DFS) in univariate analyses with a specific focus on the impact of resection margin depth. Microscopically and in line with the histological reports, the widths were stratified as coincidental margins if the tumor was in contact with the surgical margin (0 mm); widths of less than, or equal to, 1 mm or greater than 1 mm. During the follow up period, recurrence after liver resection was documented in 24 patients (48%). Early recurrence (within 6 months after liver resection) occurred in 11 patients (22% of the sample and 46% of the total recurrences), including 4 patients (36%) with liver-only recurrence and 7 patients (63%) with systemic recurrence (with or without liver recurrence). One-year and two-year mortality were 12% and 22%, respectively. According to univariate analysis, no significant differences were found in early recurrence and DFS between gender, location of the primary tumor, number and size of resected liver metastases, growth pattern and KRAS wild type. Time of diagnosis of liver metastases was the only significant prognostic factor for both DFS and for early recurrence. Moreover, histological grade of primary tumor (G2:33% vs. G3:86% vs. G4:100%; p<0.040) and synchronous presentation of liver metastases (80% vs. 20%; p<0.037) were associated with shorter DFS. No significant differences were found in the early recurrence rates and DFS in R1 versus R0 patients and even between the stratification of surgical margin size. Indeed, patients with wider-margin groups showed similar trend of recurrence in comparison with the narrow-margin group. Additionally, there was a slightly significant association between the severity of postoperative complication and the occurrence of a recurrence disease (p<0.08). In conclusion, in the present study, the lack of association between R1 status and DFS or early recurrence disease suggested that R1 margin status may be a surrogate indicator of advanced and/or more extensive disease. Even exploratory in nature, the present study suggests that the tumor biology (in term of grading and synchronous metastasis) rather than R1 resection was associated recurrence disease. So, up to date, the preferred surgical technique should be a parenchymal-sparing non-anatomic resection using modern surgical devices to keep as much liver parenchyma as possible. Furthermore, the risk of an R1 resection should not be considered a contraindication to surgery with curative intent, as neoadjuvant chemotherapy may destroy peripheral micrometastases before liver resection, minimizing consequently the residual micro-metastatic disease.