Repeat hepatectomy outcomes for colorectal liver metastases from an international multicenter collaborative

Abstract

Presenter: Cristian D Valenzuela MD | Wake Forest University Background: Resection of colorectal metastases to the liver has become the standard of care when feasible, prolonging survival. However, despite improved surgical approaches, subsequent isolated hepatic recurrences are not unusual. Repeat hepatectomy for Colorectal Liver Metastases (CLM) appears to be safe and effective for recurrent disease, but there is paucity of data with few reports from large studies. We report an experience in over one thousand surgical CLM cases in a multicenter database from five hepatobiliary institutions. Methods: An international collaborative of five institutions (Wake Forest, Mayo Clinic Jacksonville, University of California San Francisco, Yale, and University of Hong Kong) was formed to collect CLM cases performed at these locations from 2000-2018. Institutional review committees approved this project at all locations. A total of 1004 CLM hepatectomy cases were identified. Compiled data included: patient demographics, comorbidities, primary tumor and metastasis characteristics, pre-operative labs and imaging, operative characteristics including hepatectomy type, transfusions, tumor pathology features, complications, neoadjuvant and adjuvant therapies, surveillance strategies, recurrence characteristics, and survival. Kaplan-Meier analysis was performed with the Log Rank test to determine differences between subgroups. Complications were considered major if the Clavien-Dindo score was three or greater, and the Chi-Square test was used to compare subgroups. Results: For all cases, median overall survival after hepatectomy for CLM was 47.2 months, and disease-free survival was 19.0 months with a median follow-up of 32.0 months. Repeat hepatectomy was performed in 78 patients (7.9%): 51 (65%) were minor and 27 (35%) were major hepatectomies, similar to first-hepatectomies, in which 551 (61%) were minor and 358 (39%) were major. Ablations were performed as part of first-hepatectomy in 121 (13.3%) patients, and as part of second-hepatectomy in 6 patients (7.6%). From time of surgery, there was no significant difference in median overall survival (49.1 vs 47.2 months, p=0.830) or disease-free survival (19.6 vs. 19.3 months, p=0.288) after second hepatectomy compared to first hepatectomy. Patients who underwent repeat hepatectomy had improved median overall survival from time of cancer diagnosis compared to patients undergoing only one hepatectomy (87.5 vs 65.0 months, Log Rank χ2 =3.926, p= 0.048). Microscopic margin status was associated with outcomes after hepatectomy for CLM: median overall survival for R1 liver resections was 35.5 months versus 48.7 months for R0 resections (Log Rank χ2 = 11.06, p=0.001). Similarly, median disease-free survival was significantly worse for R1 resections compared to R0 resections (15.1 vs. 19.6 months; Log Rank χ2 = 5.074; p=0.024). Whether the hepatectomy was minor or major had no significant effect on median overall survival (49.7 vs. 43.6 months, Log Rank χ2 = 1.681; p=0.195). However, major hepatectomy was associated with a significantly higher number of major complications compared to minor hepatectomy (17.9% vs. 12.1%; p=0.0004). Conclusion: A second hepatectomy for recurrence was beneficial for patients with CLM, yielding improved survival compared to those only undergoing one hepatectomy. Generally, obtaining R0 margins during hepatectomy for CLM was important for overall survival. Major hepatectomy was associated with higher risk of severe complications, but was associated with similar survival compared to minor hepatectomy for CLM.