Impact of expanding criteria for resectability of colorectal metastases on short- and long-term outcomes after hepatic resection.

Background: An expansion of resectability criteria of colorectal liver metastases (CLM) is justified provided "acceptable" short-term and long-term outcomes. The aim of the present study was to ascertain this paradigm in an era of modern liver surgery.

Methods: All consecutive patients who underwent hepatic resection for CLM at our institute between 1990 and 2010 were included in the study. Ninety-day mortality and morbidity rates were determined in the total study population and in 2 separate time periods (group I: 1990-2000; group II: 2000-2010). Similarly, overall and progression-free survival rates were determined. Independent predictors of postoperative morbidity were identified at multivariate analysis.

Results: Between 1990 and 2010, 1394 hepatectomies were performed in 1028 patients. Overall perioperative mortality and postoperative morbidity rates were 1.3% and 33%, respectively. Although patients in group II were older, had more often comorbid illnesses, and presented with more extensive liver disease, similar perioperative mortality rates were observed (1.1% in group I and 1.4% in group II; P = 0.53). A trend toward a higher morbidity rate was observed in group II (34% vs 31% in group I; P = 0.16). Independent predictors of postoperative morbidity were: treatment between 2000 and 2010, total hepatic ischemia time of 60 minutes or more, maximum size of CLM of 30 mm or more at histopathology, and presence of abnormalities in the nontumoral liver parenchyma. Although a trend toward lower overall survival was observed in patients with significant postoperative complications, no significant differences were observed in long-term outcomes between both treatment periods.

Conclusion: After an aggressive multidisciplinary treatment of CLM, acceptable overall mortality and morbidity rates were observed. Perioperative mortality rates did not differ according to treatment period; however, more recently operated patients experienced more postoperative complications. These favorable short-term outcomes, without worsening of long-term outcomes, justify an expansion of the criteria for resectability in this patient category.