Brief Summary: This study will evaluate the effect of Octreotide LAR® on the liver volumes of patients with severe polycystic liver disease who are not candidates or decline surgical treatments such as liver cyst fenestration, liver resection or liver transplantation. A total of 42 patients will be recruited -14 who will receive placebo and 28 the study drug. Preliminary evidence indicates that this drug is safe and non-toxic in other disease states. Treatment with this drug holds promise not only for individuals with liver involvement, but also for many more patients with polycystic kidney disease.

Detailed Description: The primary aim of this study is to compare the effect of Octreotide LAR® Depot on the liver volume of patients with severe polycystic liver disease who are not candidates or decline surgical treatments such as liver cyst fenestration, liver resection or liver transplantation compared with placebo. The secondary aims of the study are: (1)Assess the effect of Octreotide LAR® Depot on the total kidney volume and iothalamate clearance in patients with polycystic kidney disease associated with severe polycystic liver disease who are not candidates or decline surgical treatments such as liver cyst fenestration, liver resection or liver transplantation. (2)Evaluate quality of life changes associated with the administration of Octreotide LAR® Depot in these patients. (3)Assess toxicity of Octreotide LAR® Depot in patients with polycystic liver disease (PLD). Note: Subjects who completed this 1 year randomized trial were offered enrollment into an open-label (all subjects received Octreotide) extension trial for an additional two years of treatment.