Hepatocellular carcinoma: surveillance CT schedule after hepatectomy based on risk stratification.

Abstract

To evaluate alternative schedules for surveillance computed tomography (CT) for patients who underwent hepatectomy for hepatocellular carcinoma ( HCC hepatocellular carcinoma ) and to demonstrate an appropriate schedule on the basis of stratification for risk of recurrence. CT and pathologic reports for consecutive patients with HCC hepatocellular carcinoma who underwent hepatectomy at one institution were evaluated with institutional review board approval. Univariate and multivariate analyses were performed to identify risk factors for recurrence. Patients were categorized into risk groups on the basis of classification and regression tree analysis. Average recurrence detection rates ( RDR recurrence detection rate s) between consecutive CT scans were calculated for existing and alternative surveillance schedules for each risk group, and the difference in RDR recurrence detection rate was determined by using the Student t test. A P value of less than .05 was considered to indicate a significant difference. Expected delay in diagnosis was also computed for the alternative surveillance schedules for each risk group. Two hundred sixty patients (216 men; mean age, 56.0 years ± 22.5) underwent 2705 CT studies. Independent risk factors for recurrence were microvascular invasion (P = .001), cirrhosis (P = .007), and tumor multiplicity (P = .001). Three risk groups (low, intermediate, and high) were identified. For low- and intermediate-risk groups, average RDR recurrence detection rate was not significantly different in the first 2 years after hepatectomy when the interval was extended from 3 months (3.3% and 4.6%, respectively) to 4 months (4.3% [expected delay, 16 days] and 6.1% [expected delay, 18 days], respectively) or for the subsequent 3 years when the interval was extended from 6 months (1.3% and 3.5%, respectively) to 12 months (2.5% [expected delay, 72 days] and 7.0% [expected delay, 103 days], respectively). This alternative schedule included five (35.7%) fewer CT scans than the 14 in the original schedule, and a reduction in radiation dose and cost during the 5-year follow-up period. Posthepatectomy surveillance CT schedules may be tailored and optimized according to stratification by risk of recurrence to reduce the frequency of CT scans without compromising surveillance benefits.