Operative and short-term oncologic outcomes of laparoscopic versus open liver resection for colorectal liver metastases located in the posterosuperior liver: a propensity score matching analysis.

BACKGROUND: Laparoscopic resection (LLR) of colorectal liver metastases (CRLM) located in the posterosuperior liver (segments 4a, 7, and 8) is challenging but has become more practical recently due to progress in operative techniques. We aimed to compare tumor-specific, perioperative, and short-term oncological outcomes after LLR and open liver resection (OLR) for CRLM.

METHODS: Patients who underwent curative resection of CRLM with at least 1 tumor in the posterosuperior liver during 2012-2015 were analyzed. Tumor-specific factors associated with the adoption of LLR were analyzed by logistic regression model. One-to-one propensity score matching was used to match baseline characteristics between patients with LLR and OLR.

RESULTS: The original cohort included 30 patients with LLR and 239 with OLR. Median follow-up time was 23.8 months. Logistic regression analysis showed that multiple, diameter ≥30 mm, deep location, and closeness to major vessels were associated with OLR. None of the 24 patients with none or one of these factors were converted from LLR to OLR. After matching, 29 patients with LLR and 29 with OLR were analyzed. The 2 groups had similar preoperative factors. The LLR and OLR groups did not differ with respect to operative time, intraoperative bleeding, incidence of blood transfusion, surgical margin positivity, incidence of postoperative complications, and unplanned readmission within 45 days. Median length of postoperative hospital stay was significantly shorter for LLR versus OLR (4 days [1-12] vs. 5 days [4-18]; p = 0.0003). Median recurrence-free survival was similar for patients who underwent LLR versus OLR (10.6 months for LLR vs. 13.4 months for OLR; p = 0.87).

CONCLUSIONS: Compared to OLR, LLR of posterosuperior CRLM is associated with significantly shorter postoperative hospital stay but otherwise similar perioperative and short-term oncological outcomes. Tumor-specific factors associated with safe and routine LLR approach despite challenging location are superficial, solitary, and small (<30 mm) CRLM not associated with major vessels.