Purpose: To evaluate the specificity of spiral CT for early diagnosis of small hepato-cellular carcinoma.
Patients and methods: One or several hepatic hypervascular nodules, with a diameter smaller than or equal to 3cm and suspected of corresponding to small hepato-cellular carcinoma, were detected during the arterial phase of spiral CT in 55 patients. The diagnosis of the main nodule could be established in 31 patients by pathologic examination, elevated alpha-foeto-protein level or follow-up examination.
Results: Among the 31 studied nodules, 19 were hepato-cellular carcinomas (61%) and 12 were benign (39%). Seven (78%) of the 9 nodules>20mm and 12 (54%) of the 22 nodules<=20mmm were hepato-cellular carcinomas. Three benign lesions (2 angiomas and 1 pseudo-nodule of hemodynamic origin) were showing typical radiological characteristics which retrospectively allowed their identification. On the other hand, the appearance of the 9 other benign nodules (29%) was exactly the same as the one of the hepato-cellular carcinoma.
Conclusion: Although, in cirrhotic patients, hepato-cellular carcinoma is the most frequent cause of detected nodules during the arterial phase of the spiral CT, 29% of hypervascular lesions<=3cm were benign in this study. In some cases, only follow-up examinations are able to confirm the diagnosis.