Life-threatening tamoxifen-induced hypercalcaemia.

This case report serves to emphasize two important features of metastatic breast carcinoma. First, that tamoxifen-induced flare, although a rare and self-limiting phenomenon, may be fatal and must thus be recognized and treated promptly. Secondly, those patients presenting with hypercalcaemia, as part of tamoxifen-induced tumour flare, invariably have metastatic disease but they may enjoy a durable prognosis if this is confined to the skeleton.