Liver structural transformation after partial hepatectomy and repeated partial hepatectomy in rats: A renewed view on liver regeneration

BACKGROUND The phenomenon of liver regeneration after partial hepatectomy(PH)is still a subject of considerable interest due to the increasing frequency of half liver transplantation on the one hand,and on the other hand,new surgical approaches which allow removal of massive space-occupying hepatic tumors,which earlier was considered as inoperable.Interestingly,the mechanisms of liver regeneration are extensively studied after PH but less attention is paid to the architectonics of the regenerated organ.Because of this,the question“How does the structure of regenerated liver differ from normal,regular liver?”has not been fully answered yet.Furthermore,almost without any attention is left the liver's structural transformation after repeated hepatectomy(of the re-regenereted liver).ATM To compare the architectonics of the lobules and circulatory bed of normal,regenerated and re-regenerated livers.METHODS The livers of 40 adult,male,albino Wistar rats were studied.14 rats were subjected to PH-the 1st study group(SG1);10 rats underwent repeated PH–the 2nd study group(SG2);16 rats were subjected to sham operation-control group(CG);The livers were studied after 9 months from PH,and after 6 months from repeated PH.Cytological(Schiff reaction for the determination of DNA concentration),histological(H&E,Masson trichrome,CK8 Immunohistochemical marker,transparent slides after Indian Ink injection,),morphometrical(hepatocytes areas,perimeters and ploidy)and Electron Microscopical(Scanning Electron Microscopy of corrosion casts)methods were used.RESULTS In the SG1 and SG2,the area of hepatocytes and their perimeter are increased compared to the CG(P<0.05).However,the areas and perimeters of the hepatocytes of the SG1 and SG2 groups reveal a lesser difference.In regenerated(SG1)and re-regenerated(SG2)livers,the hepatocytes form the remodeled lobules,which size(300-1200μm)exceeds the sizes of the lobules from CG(300-600μm).The remodeled lobules(especially the“mega-lobules”with the sizes 1000-1200μm)contain the transformed meshworks of the sinusoids,the part of which is dilated asymmetrically.This meshwork might have originated from the several portal venules(interlobular and/or inlet).The boundaries between the adjacent lobules(including mega-lobules)are widened and filled by connective tissue fibers,which gives the liver parenchyma a nodular look.In SG2 the unevenness of sinusoid diameters,as well as the boundaries between the lobules(including the mega-lobules)are more vividly expressed in comparison with SG1.The liver tissue of both SG1 and SG2 is featured by the slightly expressed ductular reaction.CONCLUSION Regenerated and re-regenerated livers in comparison with normal liver contain hypertrophied hepatocytes with increased ploidy which together with transformed sinusoidal and biliary meshworks form the remodeled lobulli.

Laparoscopic vs open liver re-resection for cirrhotic patients with post-hepatectomy hepatocellular carcinoma recurrence:A comparative study

BACKGROUND Repeated liver resection is an effective treatment for recurrent hepatocellular carcinoma(HCC).However,few studies have compared the outcome of laparoscopic repeat hepatectomy(LRH)and open repeat hepatectomy(ORH)for recurrent HCC,and few of those have included cirrhotic patients.AIM To compare short-term and long-term outcomes of cirrhotic patients with LRH and ORH for recurrent HCC.METHODS We retrospectively analysed the clinical records retrieved from a prospectively collected database of all patients who underwent hepatectomy for posthepatectomy recurrent HCC at our institute between May 2006 and June 2021.Cases of recurrent HCCs larger than 7 cm were excluded.Patient demographics,operative details,perioperative outcomes,pathologic details,disease-free survival(DFS),and overall survival(OS)data of LRH and ORH were compared.RESULTS Data from 29 patients with LRH and 22 with ORH were compared.The LRH group showed significantly better outcomes for blood loss(median 300 mL vs 750 mL,P=0.013)and length of hospital stay(median 5 d vs 7 d,P=0.003).The 1-,3-and 5-year OS rates in the LRH group were 100.0%,60.0%and 30.0%,respectively;the corresponding rates in the ORH group were 81.8%,36.4%and 18.2%(P=0.336).The 1-,3-and 5-year DFS rates in the LRH group were 68.2%,27.3%and 4.5%,respectively;the corresponding rates in the ORH group were 31.3%,6.3%and 6.3%(P=0.055).There were no significant differences in overall and DFS between the two groups.CONCLUSION Laparoscopic re-resection should be considered for patients presenting with recurrent HCC less than or equal to 7 cm after previous hepatectomy.