Review
Copyright ©The Author(s) 2020.
World J Gastroenterol. Nov 14, 2020; 26(42): 6529-6555
Published online Nov 14, 2020. doi: 10.3748/wjg.v26.i42.6529
Table 1 Controversial issues involving surgical strategies for colorectal cancer with synchronous resectable liver metastases
Controversial issueAdvantagesDisadvantages
Surgical strategies for synchronous CRLM:
• Traditional "staged" or "classic" approachRisks of CRR and LR are not cumulated; CHT can be usefully administered before the LRMay determine progression of CRLM, sometimes up to unresectability; manipulation of metastatic CRC may have adverse effects on distant metastases and oncological outcome
• "Reverse" or "liver-first" approachAvoids progression of borderline resectable CRLM; permits appropriate NACHRT for locally advanced rectal cancer, sometimes up to complete responseComparative results with the traditional approach are still uncertain
• Simultaneous colorectal and liver resectionReduces the number of surgical procedures; may reduce the duration of perioperative CHT; may decrease the cumulative costs of hospitalizationRequires accurate selection of candidates; may increase perioperative morbidity and mortality; oncological outcomes are still uncertain
NACHT of resectable CRLMMay reduce the extent of LR; may increase the R0 resection rates; eradicates micrometastases; may select patients with favourable oncological prognosis after LRMay determine progression of CRLM, sometimes up to unresectability; may determine parenchymal damage and increase perioperative morbidity; its overall beneficial impact on oncological outcomes has not been confirmed
Nonanatomic/parenchymal-sparing vs anatomic LRMay reduce the extent of LR; may increase resectability; may achieve better perioperative results; may favour reresection in case of hepatic recurrence, with consequent improvement of oncological resultsMay reduce the extent of the RM; its overall impact on oncological outcomes is still controversial
The prognostic role of the RM:
• ≥ 10 mmMay reduce the overall risk of recurrence; may achieve better oncological outcomesMay reduce resectability
• 1 to 10 mmMay reduce the extent of LR; may increase resectabilityMay favour tumour recurrence; may determine worse oncological outcomes
• < 1 mm (R1 resection)May increase resectabilityDetermines worse oncological outcomes; perioperative CHT is mandatory
• “R1 vascular” RM (detachment of CRLM from vessels)May reduce the extent of LR; may increase resectabilityMay favour tumour recurrence; may determine worse oncological outcomes
Evaluation of genetic mutations of CRLMPredict response to CHT; may predict response to perioperative CHT; may predict oncological results of LR; may predict positive RM in candidates for LR; may suggest more extensive/anatomical LR; may predict response to local (RFTA) and loco-regional (chemo and radioembolization) treatmentsIts overall role in establishing individualized therapeutic strategies is still uncertain; its overall impact on oncological outcomes is still uncertain
Treatment of multiple bilobar CRLM:
• NACHT of multiple resectable CRLMMay favour curative LR; may reduce the extent of LR; may increase the R0 resection rates; eradicates micrometastases; may select patients with favourable oncological prognosis after LRMay determine progression of CRLM, sometimes up to unresectability; may determine parenchymal damage and increase perioperative morbidity; its overall beneficial impact on oncological outcomes is uncertain
• PSLR vs major LR, including PVE, TSH and ALPPSReduces the extent of LR; may increase resectability; reduces the risk of PHLF; may achieve better perioperative results; may favour reresection in case of hepatic recurrenceMay reduce the extent of the RM; its overall impact on oncological outcomes is still controversial
• Intraoperative local ablation techniquesMay reduce the extent of LR; may increase resectability; may favour curative LRHigher risk of local recurrence, especially for larger tumours; its overall beneficial impact on oncological outcomes is still uncertain
The impact of PSLR on simultaneous resectionsMay reduce the extent of LR; may increase resectability of CRLM; may improve the propensity for simultaneous resection; may achieve better perioperative resultsMay reduce the extent of the RM of LR; its overall impact on oncological outcomes is still controversial
Table 2 Controversial issues involving mini-invasive (laparoscopic and robotic) surgical strategies for colorectal cancer with synchronous resectable liver metastases
Controversial issueAdvantagesDisadvantages
Mini-invasive vs open colorectal surgeryAchieves better perioperative results; achieves similar oncological resultsIn case of rectal resection, may determine a higher risk of suboptimal oncological results at histopathology; in case of rectal resection, its overall impact on oncological outcomes is still uncertain
Mini-invasive vs open liver surgeryAchieves better perioperative results; achieves at least similar oncological results; rapid technological evolution; rapid growth of surgical experience and skillUsually preferred for limited disease, in favourable locations and selected patients; may determine more complex and longer procedures; may determine more extended hepatectomies; less frequently used for major LR, including TSH and ALPPS, and for CRLM in postero-superior segments and in the caudate lobe; may determine higher costs
Mini-invasive vs open simultaneous colorectal and liver resectionAchieves better perioperative results; achieves similar oncological resultsUsually preferred for limited liver disease, in favourable locations, and higly selected patients; may determine more complex and longer procedures; may determine higher costs
Mini-invasive vs open PSLRAchieves better perioperative results; achieves similar oncological results; rapid technological evolution; rapid growth of surgical experience and skillThe principles of PSLR are time-consuming and rather difficult to apply during mini-invasive procedures; usually preferred for limited disease, in favourable locations and selected patients; may determine more complex and longer procedures; may determine higher costs
The impact of PSLR on mini-invasive simultaneous resectionMay achieve better perioperative results; may achieve similar oncological resultsMay determine more complex and longer procedures; may have very limited indications