All subjects who have received at least one dose of 90Y-DOTA-tyr3-Octreotide must continue into the Long-Term Follow-up Study Period at the point of treatment discontinuation. This is necessary to determine any long-term effects of treatment with 90Y-DOTA-tyr3-Octreotide. Subjects may receive, at the discretion of the investigator, appropriate medical treatment for medical problems that arise while on study.