Metastasis of an occult gastric carcinoma suggesting growth of a prolactinoma during bromocriptine therapy: a case report with a review of the literature.

The treatment of a slowly growing invasive prolactinoma with bromocriptine for 8 months resulted in a substantial decrease in plasma prolactin levels despite rapid suprasellar tumor expansion. On exploration, this uncommon observation could be attributed to hematogenous metastasis from an occult gastric adenocarcinoma to the pituitary tumor. Apart from infiltration of neighboring parts of the hypothalamus, autopsy revealed no other hematogenous metastases. This extraordinary type of neoplasm-to-neoplasm metastasis was not shown by computed tomography. This possibility should be considered whenever progressive growth of a pituitary mass is accompanied by a decrease in hormonal overproduction.