OPEN PARENCHYMAL SPARING POSTEROSUPERIOR LIVER TUMOR RESECTION FOR COLORECTAL LIVER METASTASIS WITH PROXIMITY TO HEPATIC VEINS

Objectives: Resection of liver tumor located in segment 7/8 of the liver is technically challenging, especially when proximity to hepatic veins is anticipated. The majority of these cases are therefore performed via the traditional open approach with goals of optimal liver parenchymal preservation and delicate hepatic vein dissection using cavitron ultrasonic surgical aspirator (CUSA). Preservation of liver parenchymal and major vascular structures are important to minimize chance of developing postoperative liver insufficiency. In this video, we present our technical approach to a dominant segment 7/8 KRAS-mutated colorectal liver metastasis with involvement of right hepatic vein (RHV) and adjacent proximity to the middle hepatic vein (MHV).

Methods: 50-year-old man presented with bilobar colorectal liver metastasis originating from sigmoid colon. After 1 year of Folfox and Folfiri systemic chemotherapy, a favorable oncological response was seen in the liver tumors. Triphasic CT scan showed a dominant liver tumor which measures 7.9 cm in segment 7/8 (size decreased from previously 14 cm). Several other hepatic metastases also responded well to treatment. The operation began with cholecystectomy and wide mobilization of hepatic lobes to facilitate access to all liver segments. Smaller tumors on the left and medial liver sectors were wedge resected. Next, a Pringle apparatus was prepared in case of the need for temporary inflow vascular occlusion. After ultrasonic mapping of intrahepatic vascular structures, specifically RHV and MHV, the resection of segment 7/8 liver tumor was started. Dissection of the liver parenchyma and skeletonization of the MHV was performed with CUSA in combination with a vessel sealing energy device and 3-0 silk ties. Dissection was undertaken with intermittent Pringle maneuver 15 minutes on and 5 minutes off for the liver reperfusion. The tumor was safely dissected off the MHV while obtaining 1cm of medial margins. A parenchymal sparing liver resection avoiding an extended right hepatectomy was accomplished, which is particularly important in patients who had undergone an extensive systemic chemotherapy treatment.

Results: The operative duration was four hours. Final pathology showed metastatic colonic adenocarcinoma (6.7 x 6.0 x 4.6 cm) with negative margins. Postoperative course was uneventful.

Conclusion: Parenchymal sparing liver resection with preservation of a major hepatic vein (MHV) was demonstrated. This approach is particularly useful to avoid a major/extended resection in the setting of prior extensive systemic chemotherapy treatment.