Propensity score analysis of non-anatomical versus anatomical resection of colorectal liver metastases.

Background: There are concerns that non-anatomical resection (NAR) worsens perioperative and oncological outcomes compared with those following anatomical resection (AR) for colorectal liver metastases (CRLM). Most previous studies have been biased by the effect of tumour size. The aim of this study was to compare oncological outcomes after NAR versus AR. Methods: This was a retrospective study of consecutive patients who underwent CRLM resection with curative intent from 1999 to 2016. Data were retrieved from a prospectively developed database. Survival and perioperative outcomes for NAR and AR were compared using propensity score analyses. Results: Some 358 patients were included in the study. Median follow-up was 34 (i.q.r. 16-68) months. NAR was associated with significantly less morbidity compared with AR (31·1 versus 44·4 per cent respectively; P = 0·037). Larger (hazard ratio (HR) for lesions 5 cm or greater 1·81, 95 per cent c.i. 1·13 to 2·90; P = 0·035) or multiple (HR 1·48, 1·03 to 2·12; P = 0·035) metastases were associated with poor overall survival (OS). Synchronous (HR 1·33, 1·01 to 1·77; P = 0·045) and multiple (HR 1·51, 1·14 to 2·00; P = 0·004) liver metastases, major complications after liver resection (HR 1·49, 1·05 to 2·11; P = 0·026) or complications after resection of the primary colorectal tumour (HR 1·51, 1·01 to 2·26; P = 0·045) were associated with poor disease-free survival (DFS). AR was prognostic for poor OS only in tumours smaller than 30 mm, and R1 margin status was not prognostic for either OS or DFS. NAR was associated with a higher rate of salvage resection than AR following intrahepatic recurrence. Conclusions: NAR has at least equivalent oncological outcomes to AR while proving to be safer. NAR should therefore be the primary surgical approach to CRLM, especially for lesions smaller than 30 mm.

A pre-operative clinical model to predict microvascular invasion and long-term outcome after resection of hepatocellular cancer: The Australian experience.

BACKGROUND: Hepatocellular cancer (HCC) is a leading cause of mortality worldwide. Liver resection or transplantation offer the best chance of long-term survival. The aim of this study was to perform a survival and prognostic factor analysis on patients who underwent resection of HCC at two major tertiary referral hospitals, and to investigate a pre-operative prediction model for microvascular invasion (MVI). METHODS: Clinico-pathological and survival data were collected from all patients who underwent liver resection for HCC at two tertiary referral centres (Royal North Shore/North Shore Private Hospitals and Westmead Hospital) from 1998 to 2012. An overall and disease-free survival analysis was performed and a predictive model for MVI identified. RESULTS: The total number of patients in this series was 125 and the 5-year overall and disease-free survival rates were 56% and 37%, respectively. MVI was the only factor to be independently associated with a poor prognosis on both overall and disease-free survival. Age ≥64 years, a serum alpha-fetoprotein (AFP) ≥400 ng/ml (×40 above normal) and tumor size ≥50 mm were independently associated with MVI. An MVI prediction model using these three pre-operative factors provides a good assessment of the risk of MVI. CONCLUSION: MVI in the resected specimen of patients with HCC is associated with a poor prognosis. A preoperative MVI prediction model offers a useful way to identify patients at risk of relapse. However, more precise predictive models using molecular and genetic variables are needed to improve selection of patients most suitable for radical surgical treatment.