Hepatobiliary Scintigraphy in Associating Liver Partition and Portal vein ligation for Staged hepatectomy: All That Glitters Is not Gold
We have read with enthusiasm the article by Truant et al,1 regarding their experience with hepatobiliary scintigraphy (HBS) to determine interstages function of the future liver remnant (FLR) and the deportalized liver in 5 patients undergoing the Associating Liver Partition and Portal vein ligation for Staged hepatectomy (ALPPS) approach. However, we are concerned about certain topics obviated in this article.
First, the group from the University of Lille states that this is “a new technique of evaluation of the liver function in the setting of ALPPS…,” and we would like to clarify that this affirmation is not accurate. Four years have already gone by since we introduced the usage of HBS to evaluate FLR function during ALPPS.2 This fact was also highlighted in an editorial published by de Santibañes and Clavien.3 Sectorial liver function evaluation has always been in our opinion of paramount importance during ALPPS, as a “sufficient” FLR volume obtained from a fast growing parenchyma is not always accompanied by a sufficient FLR function, even if truly represented by hepatocyte proliferation.4 Up to date, HBS remains the only noninvasive method to quantify sectorial liver function, representing a low-cost exam with incalculable clinical value for decision making during ALPPS. In fact, HBS has passed from selective to routine practice in our service since the last 2 years, becoming an essential tool to decide the best timing of the second stage.
Second, the authors pretend to introduce the role of the disease hemi-liver serving as an “auxiliary liver” until the FLR grown enough to afford the second stage. They stated, “we confirm using HBS that the excluded liver segments, in the interval between surgical steps, works as an auxiliary liver until its removal, once the FRL has reached an adequate volume.”1 This modern concept in ALPPS was introduced by our group a long time ago as follows “despite the fact that the excluded liver does not have any portal blood flow, it acts as an auxiliary liver that contributes to the total liver function until the contralateral lobe has grown enough to tolerate the organ's physiological function.”2 We confirmed this hypothesis in later communications after observing by HBS that the deportalized hemi-liver is still responsible of the majority of liver function 1 week after ALPPS, and that liver function progressively shifts from the diseased hemi-liver to the FLR.5
Third, surprisingly the authors did not contrasted their results to those provided by Tanaka et al,6 in an important contribution to this specific field published 1 year ago. The Japanese group included 11 patients in whom they studied by 99mTc-GSA scintigraphy/CT fused images the FLR function before and after the first stage of ALPPS, comparing the results with those of classical two-stage hepatectomy after propensity-score matching. Interestingly, contrary to the French group, they found that functional volume increase of the FLR after ALPPS appears to parallel its morphologic volume increase and even though the function increase obtained was poorer than with classical 2-stage hepatectomy, it achieved a similar proportion of FLR function at 1 week compared with classical two-stage resections at 3 weeks (52% vs 59%).6
We are happy to see that other authors have continued exploring the use of scintigraphy for interstages evaluation of FLR function during ALPPS. Even though FLR volume is still the gold standard for defining FLR sufficiency, this does not seem to be the case for interstages FLR evaluation in ALPPS. The 1-week interval dogma has been penalized in several series with high complication rates and mortality, despite all patients were operated with a theoretically sufficient FLR.