Propensity score analysis of non‐anatomicalversusanatomical resection of colorectal liver metastases

Abstract

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.

Impact of establishing a specialized hepatobiliary unit on liver resections in a non‐specialized tertiary centre in regional Australia

“…Of interest is the global trend towards parenchymal-preserving surgery over time. 13,20 Most studies have demonstrated a decrease in morbidity and mortality with parenchymal-preserving or nonanatomical resections, without compromising on margin status. 13,20 However, we found across the two periods a trend of proportionally more segmentectomies than subsegmental resections, and overall more extended hepatectomies.…”

“…13,20 Most studies have demonstrated a decrease in morbidity and mortality with parenchymal-preserving or nonanatomical resections, without compromising on margin status. 13,20 However, we found across the two periods a trend of proportionally more segmentectomies than subsegmental resections, and overall more extended hepatectomies. This may reflect more complex disease in the latter period, with fewer tumours amenable to subsegmental resection.…”

“…Interestingly, positive margin rates in Australia appear to be variable depending on the type of pathology for which resection occurred, with 30.9%, 16.2% and 4% reported for hepatocellular carcinoma, colorectal metastases, and non-colorectal non-endocrine liver metastases, respectively. [19][20][21] Meanwhile, high-volume centres worldwide such as Memorial Sloan Kettering Cancer Centre report overall R1 margin rates as low as 8%. 13 This discrepancy suggests an area for improvement within the current practice of our HPB unit.…”

“…Of interest is the global trend towards parenchymal‐preserving surgery over time 13,20 . Most studies have demonstrated a decrease in morbidity and mortality with parenchymal‐preserving or non‐anatomical resections, without compromising on margin status 13,20 .…”

Cancer‐associated stroma reveals prognostic biomarkers and novel insights into the tumour microenvironment of colorectal cancer and colorectal liver metastases

“…A retrospective case–control study design was adopted by including all patients from January 1999 to December 2012 at Royal North Shore Hospital with either synchronous or metachronous liver‐only metastatic CRC from two previously described prospectively maintained databases of resected primary CRC 11 and CRLM. 12 Patients were excluded if their primary pathology tumour was anal in origin. An equal number of ‘control’ patients matched on age, sex, grade, T and N stage of their primary CRC (AJCC staging guidelines, 7th ed.…”