Outcomes of patients with elevated α-fetoprotein level and initial negative findings at MR imaging.

PURPOSE: To evaluate interval cancer diagnosis in patients with elevated α-fetoprotein (AFP) level and initial negative findings at magnetic resonance (MR) imaging.

MATERIALS AND METHODS: The institutional review board approved this HIPAA-compliant retrospective study and waived informed consent. Seventeen patients with elevated AFP levels (>300 ng/mL [>300 μg/L]) and initial negative findings at hepatic MR imaging from 2002 to 2011 were identified. MR reports, pathology reports, and medical records were reviewed to determine outcome, including identification of hepatocellular carcinoma (HCC), and track changes in serum AFP level. Initial and follow-up MR images were reviewed to evaluate presence and size of hepatic nodules. Significance of AFP values was tested with repeated-measures analysis of variance.

RESULTS: Ten (59%) of 17 patients developed HCCs (13 tumors) after a mean of 138 days (range, 41-247 days). Nine (90%) of 10 patients with HCCs underwent follow-up MR imaging, and one patient (10%) underwent liver transplantation without MR follow-up. Of 12 HCCs in nine patients who underwent follow-up MR imaging, 10 (83%) were noted at follow-up MR imaging and two were found only at surgery. Mean diameter of visualized HCCs was 3.4 cm. Of 10 HCCs detected at follow-up MR imaging, five were identifiable in retrospect at initial MR studies (mean diameter, 1.4 cm). Serum AFP levels in patients with HCCs were significantly higher than those in patients without HCCs and progressively increased over time (P = .012).

CONCLUSION: Subsequent HCCs in patients with elevated AFP levels and initial negative findings at MR imaging are relatively common and demonstrable during short follow-up. Close follow-up (serial 3-month studies) is recommended in the setting of a steady increase in AFP level.