The effect of preoperative chemotherapy on liver regeneration after portal vein embolization/ligation or liver resection in patients with colorectal liver metastasis: a systematic review protocol

Abstract

Introduction Liver resection (LR) in patients with liver metastasis from colorectal cancer remains the only curative treatment. Perioperative chemotherapy improves prognosis of these patients. However, there are concerns regarding the effect of preoperative chemotherapy on liver regeneration, which is a key event in avoiding liver failure after LR. The primary objective of this systematic review is to assess the effect of neoadjuvant chemotherapy on liver regeneration after (LR) or portal vein embolization (PVE) in patients with liver metastasis from colorectal cancer. The secondary objectives are to evaluate the impact of the type of chemotherapy, number of cycles, and time between end of treatment and procedure (LR or PVE) and to investigate whether there is an association between degree of hypertrophy and postoperative liver failure. Methods This meta-analysis will include studies reporting liver regeneration rates in patients submitted to LR or PVE. Pubmed, Scopus, Web of Science, Embase, and Cochrane databases will be searched. Only studies comparing neoadjuvant vs no chemotherapy, or comparing chemotherapy characteristics (bevacizumab administration, number of cycles, and time from finishing chemotherapy until intervention), will be included. We will select studies from 1990 to present. Two researchers will individually screen the identified records, according to a list of inclusion and exclusion criteria. Primary outcome will be future liver remnant regeneration rate. Bias of the studies will be evaluated with the ROBINS-I tool, and quality of evidence for all outcomes will be determined with the GRADE system. The data will be registered in a predesigned database. If selected studies are sufficiently homogeneous, we will perform a meta-analysis of reported results. In the event of a substantial heterogeneity, a qualitative systematic review will be performed. Discussion The results of this systematic review may help to better identify the patients affected by liver metastasis that could present low regeneration rates after neoadjuvant chemotherapy. These patients are at risk to develop liver failure after extended hepatectomies and therefore are not good candidates for such aggressive procedures. Systematic review registration PROSPERO registration number: CRD42020178481 (July 5, 2020).

Liver regeneration after extensive hepatectomy in rats: effect of preoperative chemotherapy with intravenous 5-fluorouracil

“…Therefore, there is a demanding investigative research for increased knowledge regarding the effect of these schemes on hepatic regenerative potential 12 , a subject of crucial importance for planning liver resections, particularly major resections and rehepatectomies 13 , where the possibility of postoperative liver failure must be considered.…”

“…Additional studies are needed to explore chemotherapy administered intravenously in several cycles, since the toxicity of chemotherapy on the liver parenchyma may be related to late histological damage after several cycles of chemotherapy and dependent on the different schemes used. For this purpose, systematic review protocols may be of help, particularly if they can address the effect of different preoperative chemotherapy schemes on liver parenchyma submitted to portal vein ligation and/or major resection during colorectal liver metastasis treatment 12 .…”

Effects of virtual reality OSCE on nursing students’ education: a study protocol for systematic review and meta-analysis

“…If data are provided in other formats, such as median range or median IQR, then M±SD values are calculated following the recommendations of the Cochrane Handbook for Systematic Reviews of Interventions. 40 (5) Other information includes support from funding institutions and potential conflicts of interest. Two of the authors (PL and XD) conduct data extraction independently, and any dispute is settled by discussion.…”

Effects of virtual reality for psychological health of ICU patients: a study protocol for systematic review and meta-analysis

“…Outcome data are expressed as mean±SD (M±SD). If data are offered in other forms, such as median–range or median–IQR, then M±SD values are calculated following the recommendations of the Cochrane Handbook for Systematic Reviews of Interventions 34 and (5) other information, such as support from funding institutions and potential conflicts of interest. Two of the authors (JZ and QC) conduct data extraction independently, and any dispute is settled by discussion.…”