gms | German Medical Science

From 1992 to 2011, 312 patients with alveolar echinococcosis (AE) were diagnosed and treated at the specialized outpatient clinic of the Ulm University. Demographic and clinical data were assessed and updated from the patients’ first visits until December 2012 (end of follow-up). At that time, 232 patients (74.4%) were alive, 39 (12.5%) had died, and 41 (13.1%) were lost to follow-up. Patients were treated either by surgery with subsequent benzimidazole prophylaxis for at least 2 years (n=133), or continuous benzimidazole treatment in case of inoperability (n=157). At first diagnosis, 17 patients had inactive lesions (possible cases; Brunetti et al. [1]); 2 of them converted to an active stage 2.3 and 5.3 years after diagnosis.

Imaging and treatment schemes changed during the 20 years of observation. AE was diagnosed more often by chance in patients from 2000 onwards (48.0%) than before 2000 (28.7%). Since 2000, the disease was detected more frequently with lesions at PNM stages I and II (27.0% vs. 15.8%) according to WHO classification (Kern et al. [2]); as a consequence, radical resections were feasible in more patients (57.7% vs. 20.0%). Overall, surgical resections were less frequent since 2000 (38.2% vs. 50.5%) as were modifications of the medical treatment (29.7% vs. 59.6%) during follow-up.

Since 1993, PET-CT-scans with ¹⁸F-FDG were used routinely to visualize larval activity at time of diagnosis. For follow-up, the rationale for performing a PET-CT every other year was to monitor the effect of continuous benzimidazole treatment, as well as to detect relapses after surgery. At the end of follow-up, medical treatment had been interrupted for 25.3% of the patients, as warranted by a lack of ¹⁸F-FDG uptake in the liver at two consecutive scans, normal levels of inflammation parameters, and other criteria (see WHO treatment recommendations, Brunetti et al. [1]). Benzimidazole interruption was possible for 46.6% of the patients with surgery and 10.8% of the patients with medical treatment alone. Of 56 patients with R0 resection, 42 (75%) had stopped medical treatment.

At their last visit, the disease status of 73.1% of the patients was judged as stable, in 5.1% as progressive while under medical treatment. AE was considered as being cured in 15.7% of the patients (treatment interrupted). The 5- and 10-years’ survival rates in this cohort were 96.8% and 90.5%.

Data analysis of two decades’ experience in the management of AE showed that best care can be provided to the patients when they present at an early stage of the disease. Staging is the prerequisite for a structured therapeutic approach. As the disease is rare, expertise is best acquired in a single specialized institution; a benefit for the patients results from strict adherence to the WHO treatment recommendations.