Abstract
In order to evaluate long-term postoperative human growth hormone (HGH) and prolactin (PRL) levels by intraoperative or immediately postoperative measurement of both hormones, 17 surgically-treated cases of pituitary adenomas were analyzed. There were seven and 10 cases of HGH and PRL-producing tumors, respectively. Serum levels of HGH and PRL were measured sequentially, from the preoperative period to 1 month after surgery. Rates of decrease of hormone levels and the statistical correlation among those rates were calculated. For PRL-producing tumors (PT), significant correlation was found between short-term decreasing rate (ΔS) and 1 week decreasing rate (ΔW) (p<0.01), between ΔS and long-term decreasing rate (ΔL) (p<0.02), and between ΔW and ΔL (p<0.02). As for HGH-producing tumors (GT), there were no such correlations. In both GT and PT, no correlation was found between intraoperative decreasing rate (ΔOp) and ΔS or between ΔOp and ΔL. It is concluded that (1) intraoperative measurement of HGH and PRL cannot predict postoperative HGH and PRL levels; (2) there are remarkable differences between GT and PT in their remnant tumor reactivity and regrowth mechanisms. (3) In PT, measurement of immediate postoperative PRL levels can predict long-term postoperative PRL levels.
