Cystic echinococcosis of the liver and lung treated by radiofrequency thermal ablation: an ex-vivo pilot experimental study in animal models.
OBJECTIVE
To evaluate radiofrequency thermal ablation (RTA) for treatment of cystic echinococcosis in animal models (explanted organs).


METHODS
Infected livers and lungs from slaughtered animals, 10 bovine and two ovine, were collected. Cysts were photographed, and their volume, cyst content, germinal layer adhesion status, wall calcification and presence of daughter or adjacent cysts were evaluated by ultrasound. Some cysts were treated with RTA at 150 W, 80 degrees C, 7 min. Temperature was monitored inside and outside the cyst. A second needle was placed inside the cyst for pressure stabilization. After treatment, all cysts were sectioned and examined by histology. Cysts were defined as alive if a preserved germinal layer at histology was evident, and as successfully treated if the germinal layer was necrotic.


RESULTS
The subjects of the study were 17 cysts (nine hepatic and eight pulmonary), who were treated with RTA. Pathology showed 100% success rate in both hepatic (9/9) and lung cysts (8/8); immediate volume reduction of at least 65%; layer of host tissue necrosis outside the cyst, with average extension of 0.64 cm for liver and 1.57 cm for lung; and endocyst attached to the pericystium both in hepatic and lung cysts with small and focal de novo endocyst detachment in just 3/9 hepatic cysts.


CONCLUSIONS
RTA appears to be very effective in killing hydatid cysts of explanted liver and lung. Bile duct and bronchial wall necrosis, persistence of endocyst attached to pericystium, should help avoid or greatly decrease in vivo post-treatment fistula occurrence and consequent overlapping complications that are common after surgery or percutaneous aspiration, injection and reaspiration. In vivo studies are required to confirm and validate this new therapeutic approach.
Lamonaca
Vincenzo
V
ISMETT, University of Pittsburgh Medical Center Italy, Via E. Tricomi 1 - 90127 Palermo, Italy. vlamonaca@ismett.edu
Virga
Antonino
A
Minervini
Marta Ida
MI
Di Stefano
Roberta
R
Provenzani
Alessio
A
Tagliareni
Pietro
P
Fleres
Giovanna
G
Luca
Angelo
A
Vizzini
Giovanni
G
Palazzo
Ugo
U
Gridelli
Bruno
B
D000818:Animals; D017115:Catheter Ablation; D002417:Cattle; D004444:Echinococcosis, Hepatic / Q000469:parasitology / Q000473:pathology / Q000601:surgery*; D004445:Echinococcosis, Pulmonary / Q000469:parasitology / Q000473:pathology / Q000601:surgery*; D048209:Echinococcus granulosus; D006801:Humans; D008099:Liver / Q000469:parasitology* / Q000473:pathology; D008168:Lung / Q000469:parasitology* / Q000473:pathology; D010865:Pilot Projects; D012756:Sheep; D013696:Temperature