Bilobar spreading of colorectal liver metastases does not significantly affect survival after R0 resection in the era of interdisciplinary multimodal treatment

Bilobar colorectal liver metastases (CRLM) are often considered incurable or associated with poor prognosis even after R0 resection. In this single-center study, we evaluate the impact of CRLM spreading on recurrence-free survival (RFS) and cancer-specific overall survival (CSS) after R0 resection of CRLM with respect to multimodal treatment strategies including perioperative chemotherapy and multistep resections. Between January 2001 and December 2010, R0 resection could be achieved in 70 patients with bilobar and 100 with unilobar CRLM. Extent of disease, perioperative chemotherapy, surgical procedures, adjuvant treatment, histopathological workup, RFS, and CSS were compared between both cohorts. Forty-six (66 %) patients with bilobar and 26 (26 %) patients with unilobar CRLM received preoperative chemotherapy (p < 0.001). For bilobar CRLM, more extended and multistep resection including portal vein occlusion were performed (29 % versus 3 %; p < 0.001). Morbidity (39 % versus 28 %, p = 0.183) and mortality (1 % versus 3 %, p = 0.644) rates were comparable in both patients' cohorts. Postoperative therapy was applied in adjuvant intent to 42 (60 %) versus 51 (51 %) patients (p = 0.275). The 5-year RFS and CSS rates were 24 % versus 31 % (p = 0.169) and 42 % versus 55 % (p = 0.131), respectively. To our single-center experience, there is no significant effect of CRLM spreading (bilobar versus unilobar) on RFS and CSS rates. Bilobar CRLM are more likely to require extended multimodal efforts to achieve R0 resection.