Liver transplantation with preservation of the recipient vena cava (the "piggy-back" technique) has been proposed as an alternative to the traditional method. We performed a randomized study on 39 cirrhotic patients, 20 who underwent the piggy-back technique (group 1) and 19 the traditional method using venovenous bypass (group 2) to evaluate the feasibility and true advantages of the piggy-back technique compared to the traditional method. Two patients were switched to the conventional technique due to the presence of a caudate lobe embracing the vena cava in one patient and a caval lesion in the other. Statistically significant differences between the two groups were only found for the warm ischemia time (48.5 +/- 13 min for piggy-back vs 60 +/- 12 min for the conventional method) and for renal failure (zero cases in group 1 vs four cases in group 2). We therefore believe that liver transplantation with the piggy-back technique can easily be performed in almost all cases, and that only a few, specific situations, such as a very enlarged caudate lobe, do not justify its routine use.