Pathophysiological mechanisms of ALPPS: experimental model

Abstract

Background Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) is a two-stage strategy that may increase hepatic tumour resectability and reduce postoperative liver failure rate by inducing rapid hypertrophy of the future liver remnant (FLR). Pathophysiological mechanisms after the first stage of ALPPS are poorly understood. Methods An ALPPS model was established in rabbits with liver VX2 tumour. The pathophysiological mechanisms after the first stage of ALPPS in the FLR and tumour were assessed by multiplexed positron emission tomography (PET) tracers, dynamic contrast-enhanced MRI (DCE-MRI) and histopathology. Results Tumour volume in the ALPPS model differed from post-stage 1 ALPPS at day 14 compared to control animals. 18F-FDG uptake of tumour increased from day 7 onwards in the ALPPS model. Valid volumetric function measured by 18F-methylcholine PET showed good values in accurately monitoring dynamics and time window for functional liver regeneration (days 3 to 7). DCE-MRI revealed changes in the vascular hyperpermeability function, with a peak on day 7 for tumour and FLR. Conclusion Molecular and functional imaging are promising non-invasive methods to investigate the pathophysiological mechanisms of ALPPS with potential for clinical application.

Correlation between the liver transection line localization and future liver remnant hypertrophy in associating liver partition and portal vein ligation for staged hepatectomy

“…Although some FIGURE 4 CT images after stage one showing partitioned liver and surgical clips along the transection line. authors recommend prolonging the interval between the two stages to 3-4 weeks, most support the thesis that a prolonged waiting period may increase the risk of tumor growth and metastasizing (3,8,24,25). Second volumetry showed a significant TLV increase in both groups.…”

“…Previous research has shown significant variability in FLR hypertrophy following ALPPS, prompting investigations into various technical aspects and disease factors influencing outcomes. Therefore, many authors studied technical ALPPS characteristics, liver parenchymal condition, and patient comorbidities as potential factors of FLR hypertrophy ( 2 , 3 , 8 , 13 – 16 ). However, the impact of the liver transection line on FLR hypertrophy has not been thoroughly explored, and understanding the dynamics of FLR hypertrophy is critical for optimizing surgical outcomes and minimizing complications.…”

“…The length of HI and ISI followed recommendations, mostly from 6 to 9 days for HI and 7–12 days for ISI. Although some authors recommend prolonging the interval between the two stages to 3–4 weeks, most support the thesis that a prolonged waiting period may increase the risk of tumor growth and metastasizing ( 3 , 8 , 24 , 25 ).…”

“…Hence, several methods have been developed to stimulate future liver remnant (FLR) hypertrophy, and one of these is "Associating liver partition and portal vein ligation for staged hepatectomy" (ALPPS), which has received a lot of attention in the surgical community over the last decade. Previous research has identified tumor-related factors, liver parenchymal condition, and intraoperative characteristics influencing FLR hypertrophy in ALPPS (2)(3)(4). However, additional research is necessary to clarify the exact mechanism underlying such intense and rapid FLR hypertrophy.…”