ORAL PAMIDRONATE IN THE PREVENTION AND TREATMENT OF SKELETAL METASTASES IN PATIENTS WITH BREAST-CANCER

Bone metastases are common in patients with breast cancer and cause co nsiderable morbidity and deterioration of the quality of life. The mai n pathogenetic mechanism is stimulation of osteoclastic bone resorptio n by factors produced by the cancer cells. Pamidronate given intraveno usly suppresses bone resorption and is an effective treatment of malig nancy-associated hypercalcemia. Recent data indicate that it can also reduce skeletal morbidity in normocalcemic patients with breast cancer and osteolytic metastases. In a series of studies we examined the lon g-term efficacy of oral pamidronate in the prevention and treatment of skeletal metastases in patients with breast cancer. In patients with bone metastases oral pamidronate given for a median period of about 20 months reduced significantly skeletal morbidity and had a favourable effect on selective aspects of the quality of life of the patients. Tr eatment did not alter the radiological course of the disease or the ov erall survival of the patients. In contrast, oral pamidronate given to patients with advanced breast cancer but no demonstrable bone metasta ses did not prevent or delay the appearance of the first clinical or r adiological manifestation of bone metastases. This treatment is theref ore very effective in patients with established metastatic bone diseas e. More studies are needed to define the place of pamidronate (and of other bisphosphonates) in the prevention of bone metastases in patient s at risk.