3 The improved sensitivity of the new diagnostic algorithm changes the definition of an DAPT chemical structure indeterminate nodule (to lack of typical features on only one imaging modality), with the result that there will be fewer HCCs among these nodules than among those defined by the older standard. Therefore, biopsying all indeterminate 1-2-cm nodules appears impractical. Our study demonstrates that selective application of biopsy to nodules with specific features can substantially reduce the number of biopsies and increase the proportion of malignant nodules found. Our results show that had biopsy been reserved for indeterminate 1-2-cm nodules demonstrating arterial hypervascularity in at

least one of the scans or in the presence

of a typical synchronous HCC, 8 of 13 malignancies would have been detected, and the number of biopsies would have decreased 3-fold (from 85 to buy Carfilzomib 23). Such a strategy would yield a sensitivity of 62% and specificity of 79% (Table 3) for detection of malignancy by biopsy among indeterminate 1-2-cm nodules. Though this sensitivity is not optimal, close imaging follow-up will very likely detect malignant transformation in the remainder of the nodules within the curable stage. All such nodules in our study were thus treated by radiofrequency ablation. Furthermore, arterial hypervascularity has been linked to more sinister tumor differentiation by a number of publications, and limiting biopsy to these nodules may result in the identification of tumors with a worse prognosis.7-10 Conversely, it is possible that the application of biopsy to all indeterminate find more 1-2-cm nodules may result in an overdiagnosis of HCC (i.e., the diagnosis and treatment of histologically malignant nodules), which may

not cause significant disease in patients.11 Although the concept of “very early HCCs,” which do not exhibit the imaging findings of typical HCCs, has now been adopted internationally by liver pathologists, there is no study of the clinical significance of these nodules.12 What proportion of very early HCCs will progress to the more advanced HCCs, and over what time frame? The rationale behind the current framework of HCC treatment algorithms, including transplantation criteria, have been based primarily on more advanced HCCs, diagnosed using imaging studies in the 1990s.13 In the setting of a competing potentially fatal disease (i.e., cirrhosis), both the identification and treatment of “very early HCCs” has yet to be justified. One strength of this study is that long-term stability was used as the reference standard for benignity. Nodules not clearly malignant, even those diagnosed as benign by biopsy, were followed for a mean of 29.9 months (range, 19-44). Because of a substantial false-negative rate of biopsy, the AASLD guidelines recommend follow-up of all indeterminate nodules by imaging for 18-24 months.