BACKGROUND: Preoperative portal vein embolization (PVE) is used to increase the future remnant liver (FRL) in patients requiring extensive liver resection. Computed tomography (CT) volumetry, performed not earlier than 3-6 weeks after PVE, is commonly employed to assess hypertrophy of the FRL following PVE. Early parameters to predict effective hypertrophy are therefore desirable. The aim of the present study was to assess plasma bile salt levels, triglycerides (TG), and apoA-V in the prediction of the hypertrophy response during liver regeneration. METHODS: Serum bile salt, TG, and apoA-V levels were determined in 20 patients with colorectal metastases before PVE, and 5 h, 1, and 21 days after PVE, as well as prior to and after (day 1-7, and day 21) subsequent liver resection. These parameters were correlated with liver volume as measured by CT volumetry (%FRL-V), and liver function was determined by technetium-labeled mebrofenin hepatobiliary scintigraphy using single photon emission computed tomography. RESULTS: Triglyceride levels at baseline correlate with volume increase of the future remnant liver (FRL-V) post-PVE. Also, bile salts and TG 5 h after PVE positively correlated with the increase in FRL volume (r=0.672, p=0.024; r=0.620, p=0.042, resp.) and liver function after 3 weeks (for bile salts r=0.640, p=0.046). Following liver surgery, TG levels at 5 h and 1 day after resection were associated with liver remnant volume after 3 months (r=0.921, p=0.026 and r=0.981, p=0.019, resp). Plasma apoA-V was increased during liver regeneration. CONCLUSIONS: Bile salt and TG levels at 5 h after PVE/resection are significant early predictors of liver volume and functional increase. It is suggested that these parameters can be used for early timing of volume assessment and resection after PVE.