Primary Hyperparathyroidism and Lymphoproliferative Diseases: Three Case Reports.

Pathophysiologic mechanisms of malignancy-associated hypercalcemia are varied. The association of neoplasia and primary hyperparathyroidism (PHP) has been illustrated by clinical cases and by epidemiologic studies which have pointed to an increased risk of different malignancies during PHP. The authors report two cases of monoclonal gammapathy and one case of chronic lymphocytic leukemia (CLL) associated with PHP. A 58-year-old man presented with hypercalcemia due to PHP after remission for multiple plasmacytoma was obtained. A 70-year-old man was hospitalized for malaise, studies showed major hypercalcemia and benign monoclonal gammapathy. In the two cases, resolution of hypercalcemia was obtained by parathyroidectomy. The third patient was a 84-year-old woman with CLL who continued to deteriorate despite response to therapy, further studies confirmed hyperparathyroidism Physiopathogenic mechanisms of this association are discussed. The PHP-malignancy association should be considered ifthe symptoms or outcome of anyone of the two diseases are atypic.