We read with great interest the position article by Rockey et al.1 recently published in HEPATOLOGY. We agree with the authors that, despite the current enthusiasm for using noninvasive tests, liver biopsy remains an important tool in the evaluation of patients with liver disease.
However, we would like to emphasize that although it is recommended that an optimal liver biopsy specimen should have 11 or more complete portal tracts (CPTs) or be longer than 20 to 25 mm for the assessment of chronic viral hepatitis, there are several additional considerations2, 3 because more than one pass is likely for most percutaneous liver biopsy (PLB) procedures in order to achieve an adequate liver sample size. Indeed, in our systematic review,4 we showed that the mean length and number of CPTs in PLB series reported in the literature were 17.7 ± 5.8 mm and 7.5 ± 3.4, respectively, which are less than the optimal standards. Interestingly, in the same review,4 ultrasound guidance and more experienced operators were important factors for the length of PLB but not for the number of CPTs. Thus, on the basis of documented PLB series in the literature, more than one pass is likely to be needed, but this increases the risk of complications with PLB,5, 6 making the minimum requirement for optimal PLB unrealistic and potentially more dangerous for the patient. On the other hand, the main advantage of transjugular liver biopsy (TJLB) is that there is no penetration of Glisson's capsule and, therefore, bleeding is extremely rare.7 Thus, a review of TJLB series reported in the literature8 showed that the mean length and number of CPTs with TJLB after an average of 2.5 passes were 12.8 ± 4.5 mm and 6.8 ± 2.3, respectively. In addition, TJLB with three passes using a Tru-Cut 19-G needle yielded liver biopsy specimens comparable to PLB specimens (the mean length and number of CPTs were 22 ± 7 mm and 8.7 ± 5, respectively) without any serious complications,9 whereas TJLB with four passes provided liver specimens with a significantly greater number of CPTs in comparison with TJLB with three passes.10 Thus, at least four passes with TJLB should be performed when liver specimens are needed for histopathological hepatitis grading and staging. Moreover, hepatic venous pressure gradient measurements can be performed concomitantly, and this might be a better endpoint than histology for the assessment of the therapeutic benefit of antiviral therapy.11 These data show that, although the costs of TJLB are higher than those of PLB, it could be an alternative and safe approach for obtaining samples of adequate size for a reliable assessment of liver histology.
Regarding liver biopsy devices, we have found that the PLB Menghini needles yield significantly longer samples (19.9 ± 6.6 mm) than PLB using Tru-Cut needles (19.9 versus 14.3 mm, P = 0.016),4 whereas TJLB using Tru-Cut needles8 provides better samples than TJLB using Menghini needles (14.5 versus 9.5 mm, P = 0.008). Finally, apart from the length and width, fragmentation also determines the quality of a liver biopsy specimen. In our recent study,10 we found that fragmentation occurs during the handling of the biopsy specimen, just after it has been obtained, and not during histological preparation.