Surgical treatment of hydatid disease of the liver. A 20-year experience. The medical records of 135 consecutive patients (74 women and 61 men) who underwent surgery for hydatid liver disease were reviewed. The patients ranged in age from 4 to 81 years. Twenty-seven patients had undergone previous surgery for hydatid liver disease. Cysts were solitary in 100 patients and multiple in 35 patients. Seventeen patients had concomitant extrahepatic disease. Conservative procedures were used in 71 patients (capitonnage in 50 patients and partial pericystectomy in 21 patients). Radical procedures were used in 64 patients (total pericystectomy in 35 patients, subtotal pericystectomy in 16 patients, and wedge or major liver resection in 13 patients). Operative mortality was 2.2% and morbidity rate was 23.7%. Recurrent disease was found in 13 patients at a mean interval of 3 years from the first operation. Better short- and long-term results were obtained with the use of radical procedures. 