Stereological evaluation of treatment response in patients with non-resectable hepatic alveolar echinococcosis using computed tomography via the Cavalieri method.

摘要

INTRODUCTION: The purposes of this study were to describe and adapt the relevant methods of computed tomography (CT) and stereology to estimate parasitic volume in the liver, to compare the efficiency of benzimidazole treatment in hepatic alveolar echinococcosis (AE), and to determine whether the response rates measured by the stereological method are correlated with those measured by simple volumetric measurements (SVM). METHODS: Nine eligible patients with non-resectable AE were included in the study. By using their abdominal CT at the baseline and after a year of treatment, treatment responses of the cases were evaluated both by the stereological method via a software and by SVM, retrospectively. The volume estimation was performed in our study using a different approach that consisted of three separate stages combined with the Cavalieri method of modern design stereology. RESULTS: The response rates were -17 +/- 55% and -12 +/- 37% by the Cavalieri method and SVM, respectively; however, they were not statistically significant (P = 0.59 and 0.21 for the Cavalieri method and SVM, respectively). Although some cases had comparable results, others had different response rates, and the two methods showed no significant correlation (r = -0.31, P = 0.41). CONCLUSIONS: Because this modified method provides accurate results by reducing margin of errors, even in case of bizarre shape of AE, a correct, unbiased, and reliable management of the cases with AE via this method may be possible. Owing to lack of a correlation with SVM, it is suggested that a measurement via SVM may be wrong and its use in the evaluation of the treatment response in such cases will not be sufficient and completely true.