ABSTRACT
Bisphosphonates are potent inhibitors of bone resorption and approved agents for both the prevention and treatment of osteoporosis. Many clinical studies have shown a consistent reduction in the risk of vertebral fractures with the use of these drugs, while others have shown a clear reduction in the risk of hip and other non-vertebral fractures. The bisphosphonates are divided into three generations based on their potency and chemical structure. In general, as a substance group they are well tolerated and, when applied correctly, the toxicity is low. Alternative dosages, e.g. monthly, three times a month or yearly as an oral drug or i.v. would probably improve patient compliance. Clinical studies have also shown the safety and effectiveness of bisphosphonates over a period of 3-7 years.
Subject(s)
Bone Density Conservation Agents/therapeutic use , Diphosphonates/therapeutic use , Osteoporosis/drug therapy , Administration, Oral , Bone Density/drug effects , Bone Density Conservation Agents/adverse effects , Bone Resorption/prevention & control , Clinical Trials as Topic , Diphosphonates/adverse effects , Fractures, Spontaneous/prevention & control , Humans , Infusions, Intravenous , Osteoporosis/etiology , Spinal Fractures/prevention & control , Structure-Activity RelationshipABSTRACT
Plasma levels of calcitonin and carcinoembryonic antigen (CEA) were determined pre-operatively and two months postoperatively in ten patients with C-cell carcinoma as part of multiple endocrine neoplasia type II. In addition, CEA was measured in extracts from 20 different phaeochromocytomas (five from patients with multiple endocrine neoplasia type II, 15 from patients with sporadic phaeochromocytoma). In comparison, CEA concentration was determined in extracts from five C-cell carcinomas of patients with multiple endocrine neoplasia type II. When correlating pre- and postoperative calcitonin and CEA levels, there was a significant linear relationship (P less than 0.001). CEA concentration in extracts from phaeochromocytomas was at the lower level of sensitivity (4.7 +/- 12.2 pg/mg tumour wet-weight). In extracts from C-cell carcinomas they were much higher (6402 +/- 4570 pg/mg tumour wet-weight). The results suggest that it is possible, in patients with phaeochromocytoma and high calcitonin levels, to differentiate by additional CEA determination between C-cell carcinoma in the course of multiple endocrine neoplasia type II and sporadic phaeochromocytoma with ectopic calcitonin liberation.
