Concept:

• Both HCC and benign entity are considered moderate probability

 Definition:

• Observation that does not meet unequivocal criteria for other LI-RADS categories. 

Criteria

Not definite benign entity, not probable benign entity, not non-HCC malignancy, not tumor in vein and one of the following:

• Mass with hepatic arterial phase hypo- or isoenhancement
  • < 20mm mass with ≤ 1 of following: “washout”, “capsule”, and threshold growth
  • ≥ 20mm mass with none of following: “washout”, “capsule”, and threshold growth
• Mass with hepatic arterial phase hyperenhancement
• < 20mm mass with none of following: “washout”, “capsule”, and  threshold growth

If unsure about category

• Categorize as LR-M if unsure between LR-3 and LR-M
• Categorize as LR-3 if unsure between LR-3 and LR-5V
• Categorize as LR-3 if unsure of LR-2 or LR-4 using tie breaker rules

 Reporting:

• LR-3 observations should be reported.
• Features seen on CT and MR can be integrated to yield the final LI-RADS category.  If this is done, it must be explicitly stated in the radiology report.
• LR-3 observations are indeterminate for HCC.  If other, more suspicious observations are not present, LR-3 observations should be reported.  If other, more suspicious observations are present (LR-M, LR-5V, LR-5, or LR-4), the LR-3 observations may be reported at the radiologist’s discretion.
• LR-3 observations may be reported in aggregate.

 Management:

• Appropriate management is variable, depending mainly on observation diameter and stability, as well as clinical and considerations. 
• Please see diagnostic options for further discussion

Comments:

• LR-3 observations, in the absence of LR-4, LR-5 and LR-M observations, should be reported to alert the referring physician to a lesion that is neither probably benign, nor suspicious for HCC. This allows the physician to consider altering their follow-up interval or to consider additional imaging studies, as clinically warranted.
• In contrast to LI-RADS, UNOS/OPTN-category 1-3 are not as clearly defined.