Patient description: The patient is a 53-year-old man complaining of frequent headaches, generalized bone pain and difficulty chewing that started 6 years ago and is getting worse. Examination shows bilateral swellings around the molars. The swellings have increased since his last examination. Several extraoral lesions of the head and face are detected. The swellings are non-tender and attached to the underlying bone. Further evaluation shows increased uptake of radioactive substance as well as an increase in urinary pyridinoline. The serum alkaline phosphatase is 300 IU/L (the normal range is 44- 147 IU/L). The patient's sister had the same problems. She was diagnosed with Paget's disease of bone when she was 52 years old. The diagnosis of Paget's Disease of Bone is confirmed and Bisphosphonate will be started as first-line therapy.

Clinical trial eligibility criteria: eligible ages (years): 18.0-999.0,  Osteoporosis Prostate Cancer Pathologically (histologically or cytologically) proven diagnosis of adenocarcinoma of the prostate within 12 months of registration Any one of the following clinical stages T3 disease, any N stage, M0 with any Gleason score and any prostate-specific antigen (PSA); < T3 stage, any N stage, M0 with Gleason's score ≥ 8 and any PSA; < T3 stage, any N stage, M0 with Gleason's score 7 and PSA ≥ 15 nanograms/ml; < T3 stage, any N stage, M0 with Gleason score < 7 and PSA ≥ 20 nanograms/ml A negative bone scan for metastatic disease It is mandatory that the treating physician determine the planned duration of LHRH therapy prior to the site registering the patient (minimum 1 year of therapy); If patient is receiving pre-treatment LHRH therapy, it must have begun ≤ 6 months prior to registration. If pelvic radiation therapy (RT) has started, it must have begun ≤ 8 weeks prior to registration Appropriate stage for protocol entry, including no distant metastases, based upon the following minimum diagnostic workup to be done within 16 weeks prior to registration History/physical examination Dental evaluation, including history of dental surgery (e.g., extraction or implant) Bone scan T and L spine films  Prior invasive malignancy (except non-melanomatous skin cancer) unless disease free for a minimum of 3 years; e.g., carcinoma in situ of the breast or oral cavity are permissible Patients with baseline T scores of ≤ -2.5 are excluded Patients with baseline calculated creatinine clearance < 30 mL/min (estimated by Cockcroft-Gault formula below) are excluded. creatinine clearance male = [(140 age) x (wt in kg)] / [(serum creatinine) x (72)] Prior bisphosphonate therapy Prior pelvic radiation (other than for current prostate cancer) or prior systemic radiotherapeutic agents, such as strontium or samarium Patients receiving systemic chemotherapy, steroids, growth hormones, or calcitonin Patients with a history of Paget's disease or with uncontrolled thyroid or parathyroid dysfunction or with other diseases that influence bone metabolism Known hypersensitivity to zoledronic acid or other bisphosphonates Active dental problems at study entry, including infection of the teeth or jawbone; dental or fixture trauma; or a current or prior diagnosis of osteonecrosis of the jaw, exposed bone in the mouth, or slow healing after dental procedures