Value of CT in determining the resectability of hepatoblastoma before and after chemotherapy.

OBJECTIVE: The purpose of this study was to assess the accuracy of CT for determining surgical resectability of hepatoblastoma before and after chemotherapy.

MATERIALS AND METHODS: Preoperative and postoperative CT scans of 15 children with surgically confirmed hepatoblastoma were retrospectively reviewed and correlated with surgical findings and pathologic analysis.

RESULTS: Before chemotherapy, 12 of the 15 children had unresectable tumors because of bilobar involvement, metastatic disease, or vascular extension. After chemotherapy, tumor volumes decreased by 20-98%, with increased areas of low attenuation and calcification. Periportal areas of low attenuation (four of nine), abdominal adenopathy (four of four), and lung nodules (four of six) disappeared after chemotherapy. On the basis of CT and clinical findings, all tumors were thought to be resectable. Surgical correlation showed that the extent of hepatic tumor had been overestimated on immediate preoperative CT scans in three children (tumor was staged as bilobar, but only single-lobe resection was required). Correlation between areas of low attenuation in the tumor and necrosis in pathologic specimens was poor. Tumor invasion of periportal lymphatics was seen in one of five children with periportal areas of low attenuation. Postoperatively, five of 13 children had CT abnormalities, three at the resection margins with calcification, low attenuation, or both. Hepatic or abdominal disease has not recurred, and 12 of the 14 children who survived surgery are well. One child who had abnormal findings on preoperative chest CT died of pulmonary metastases. Another in whom chemotherapy was limited because of toxic effects died after tumor recurred in the liver.

CONCLUSION: Pretreatment CT scans cannot be used to predict ultimate resectability of hepatic tumors; nor are preoperative scans always accurate for judging exact lobar involvement. Absence of disease as shown on CT scans correlated with absence both at surgery and at follow-up. Postoperative hepatic changes are common and do not necessarily reflect recurrent or residual tumor.