Table 5.
OPTN classification system for nodules seen on images of cirrhotic livers
| Class and description | Comment |
|---|---|
| OPTN class 0: incomplete or technically inadequate study | Repeat study required for adequate assessment; automatic MELD priority points cannot be assigned on basis of an imaging study categorized as OPTN class 0 |
| OPTN class 5: meets radiologic criteria for HCC | May qualify for automatic exception depending on stage |
| OPTN class 5A: lesion ≥1 cm, <2 cm measured in late arterial or portal venous phase images | Increased arterial enhancement during the late hepatic arterial phase and washout during the later phases of contrast enhancement and peripheral rim enhancement (capsule or pseudocapsule) |
| OPTN class 5A-g: same size as OPTN class 5A HCC | Increased contrast enhancement in the late hepatic arterial phase and growth by ≥50% documented on serial CT or MR images obtained ≤6 months apart |
| OPTN class 5B: maximum diameter ≥2 cm and ≤5 cm | Increased contrast enhancement in the late hepatic arterial phase and either washout during later contrast phases or peripheral rim enhancement (capsule or pseudocapsule), 50% growth or more documented on serial CT or MR images obtained 6 months apart (OPTN class 5B-g) |
| OPTN class 5T: prior regional treatment for HCC | Any residual lesion or perfusion defect at site of prior UNOS class 5 lesion |
| OPTN class 5X: maximum diameter ≥5 cm | Increased contrast enhancement in the late hepatic arterial phase and either washout during later contrast phases or peripheral rim enhancement (capsule or pseudocapsule) |
Notes: Data from OPTN/UNOS Liver and Intestinal Organ Transplantation Committee. Report to the Board of Directors; 2016. Available from: http://optn.transplant.hrsa.gov.37 Reproduced, with permission, from Wald C, Russo MW, Heimbach JK, Hussain HK, Pomfret EA, Bruix J. New OPTN/UNOS policy for liver transplantation allocation: standardization of liver imaging, diagnosis, classification, and reporting of hepatocellular carcinoma. Radiology. 2013;266(2):376–382.23
Abbreviations: HCC, hepatocellular carcinoma; CT, computed tomography; MR, magnetic resonance; UNOS, United Network for Organ Sharing; OPTN, Organ Procurement and Transplantation Network; MELD, Model for End-Stage Liver Disease.