01 Set Medical treatment versus “Watch and Wait” in the clinical management of CE3b echinococcal cysts of the liver

Francesca Rinaldi

Available treatments for uncomplicated hepatic cystic echinococcosis (CE) include surgery, medical therapy with albendazole (ABZ), percutaneous interventions and the watch-and-wait (WW) approach. The transitional CE3b cysts are the least responsive to non-surgical treatment and evidence supporting indications for their treatment is lacking. In the attempt to fill this gap , we compared the clinical behavior of single hepatic CE3b cysts in 60 patients followed over 27 years (who either received ABZ or were monitored with WW) at the WHO Collaborating Centre for Cystic Echinococcosis of the University of Pavia. Univariate and multivariate analysis were performed to investigate the effect on outcome (inactivation or relapse) of different variables using a multiple failure Cox proportional hazard model. ABZ treatment was positively associated with inactivation (p < 0.001), but this was not permanent, and no association was found between therapeutic approach and relapse (p = 0.091). No difference was found in the rate of complications between groups. In conclusion, our study shows that ABZ treatment induces temporary inactivation of CE3b cysts, while during WW cysts remain stable over time. As the rate of adverse events during periods of ABZ treatment and WW did not differ significantly in the follow-up period considered in this study, expectant management might represent a valuable option for asymptomatic CE3b cysts when strict indication for surgery is absent and patients comply with regular long-term follow-up.