Portal vein embolization and ligation for extended hepatectomy

Portal vein occlusion through embolization or ligation (PVE, PVL) offers the possibility of increasing the future liver remnant (FLR) and thus reducing the risk of hepatic failure after extended hepatectomy We reviewed the indications, scope and applicability of PVE/PVL in treatment of primary and secondary liver tumours. A thorough PubMED, Embase, Ovid and Cochrane database search was carried out for all original articles with 30 patients or more undergoing either PVE and any patient series with PVL, irrespective of number with outcome measure in at least one of the following parameters: FLR volume change, complications, length of stay, time to surgery, proportion resectable and survival data. PVE can be performed with a technical success in 98.9 % (95 % confidence interval 97-100) patients, with a mean morbidity of 3.13 % (95 % CI 1.21-5.04) and a median in-hospital stay of 2.1 (range 1-4) days (very few papers had data on length of stay following PVE). The mean increase in volume of the FLR following PVE was 39.75 % (95 % CI 30.8-48.6) facilitating extended liver resection after a mean of 37.13 days (95 % CI 28.51-45.74) with a resectability rate of 76.88 % (95 % CI 70.91-82.84). Morbidity and mortality following such extended liver resections after PVE is 26.58 % (95 % CI 19.20-33.95) and 2.59 % (95 % CI 1.34-3.83) respectively with an in-patient stay of 13.57 days (95 % CI 9.8-17.37). However following post-PVE liver hypertrophy 6.29 % (95 % CI 2.24-10.34) patients still have post-resection liver failure and up to 14.2 % (95 % CI -8.7 to 37) may have positive resection margins. Up to 4.80 % (95 % CI 2.07-7.52) have failure of hypertrophy after PVE and 17.46 % (95 % CI 11.89-23.02) may have disease progression during the interim awaiting hypertrophy and subsequent resection. PVL has a greater morbidity and duration of stay of 5.72 % (95 % CI 0-15.28) and 10.16 days (95 % CI 6.63-13.69) respectively; as compared to PVE. Duration to surgery following PVL was greater at 53.6 days (95 % CI 32.14-75.05). PVL induced FLR hypertrophy by a mean of 64.65 % (95 % CI 0-136.12) giving a resectability rate of 63.68 % (95 % CI 56.82-70.54). PVL failed to produce enough liver hypertrophy in 7.4 % of patients (95 % CI 0-16.12). Progression of disease following PVL was 29.29 (95%CI 15.69-42.88). PVE facilitates an extended hepatectomy in patients with limited or inadequate FLR, with good short and long-term outcomes. Patients need to be adequately counselled and consented for PVE and EH in light of these data. PVL would promote hypertrophy as well, but clearly PVE has advantages as compared to PVL on account of its inherent "minimally invasive" nature, fewer complications, length of stay and its feasibility to have shorter times to surgery.