Study to Investigate Adherence of Patients to Clodronate (Bonefos) Treatment

Adherence (or compliance with) a medication regimen is generally defined as the extent to which patients take medication as prescribed by their health care providers. The adherence to medications has close relation to effectiveness of the therapy. The primary objective of this study is to observe the adherence to treatment with oral clodronate (PDC, proportion of days covered, number of days in which clodronate is taken according to treating physician recommendation) in patients with malignancy. The secondary "hypothesis generating" objective is to describe the relation between adherence to treatment with oral clodronate and efficacy of the therapy (skeletal events, pain).