ROBOT-ASSISTED SURGERY FOR COLORECTAL LIVER METASTASIS: A SINGLE CENTER EXPERIENCE

Purpose Although minimally invasive surgery (MIS) of the liver is increasingly widespread, its role in the treatment of colorectal metastasis (CRLM) remain uncertain. Frequent issues regard feasibility and oncological safety of MIS for CRLM are considered: multiple localization, inherent limitations of the intra-operative laparoscopic probes in performing a complete study of the liver, synchronous presence of primary tumor to be resected or previous surgery. In this setting, the role of robot-assisted surgery (RAS) has not been evaluated in literature yet. The aim of this study, is to report our experience with RAS for treatment of CRLM. Materials and methods Surgical and oncological data of all the robot-assisted liver resections for CRLM performed at our center, were retrieved from the prospectively-collected Institutional database, and retrospectively analyzed. All the resections were performed with the da Vinci platform (Si since 2012, and Xi since 2015 for multiple organs resections), through a combined used of monopolar scissors (right hand), and of bipolar Maryland forceps or Gyrus PK SuperPulse Generator (left hand). Intra-operative US scan was obtained with a dedicated robotic probe using the TilePro™ function. Results Sixteen patients underwent robot-assisted resection of CRLM, between May 2012 and July 2017. Four patients (25%) had multiple synchronous CRLM resections (median = 2; range 2 – 3). The tumor size averaged 3.1  1.6 cm. All the lesions were removed following a parenchymal sparing approach, with R0 resection margins. In two cases, with the aid of da Vinci Xi, a synchronous colon resection was performed, whereas in the remaining cases the primary cancer had already been removed (8/14, 57%, with MIS and 6/14, 43%, with traditional approach). There was no conversion to open surgery and no intraoperative complications. Mean hospital stay was 4.5  1.4 days. The mean follow up was 27.3 ± 19 months. During the study period there were no local recurrences; while 7 patients (43%) developed new systemic metastasis. Eight patients (50%) were treated with pre-operative systemic chemotherapy whereas eleven cases (68%) underwent post-operative chemotherapy. All patients are still alive with a 1 and 3 years disease-free survival of 77.5% and 36.3% respectively. Conclusions In our experience, RAS for CRLM surgical treatment was feasible, and played a positive role even in multiple localization and previous or synchronous surgery. The availability of a dedicated US scan intraoperative probe, managed directly with the dominant hand of the surgeon, similarly to the open approach, could improve safety in the management of multiple localization. The da Vinci Xi could improve ability to perform multiquadrant surgery, particularly useful in presence of synchronous primary tumor to be resected. RAS seemed to be oncologically safe in this setting, as no patients experienced local relapse in the treated area.