Amino acid metabolism in pituitary adenomas.
Patients with pituitary adenomas were examined with positron emission tomography with the administration of 11C-labelled methionine. In a few patients comparative studies using the two stereo-isomers L- and D-methionine were also performed. The results showed a rapid distribution of D-methionine within the tumor tissue without signs of irreversible trapping of the tracer. L-methionine on the other hand was rapidly irreversibly trapped indicating the metabolic fate. It is concluded that 11C-L-methionine can be used to quantify amino acid metabolism in the tumors. The amino acid metabolism was evaluated in a group of adenomas before and after treatment with bromocriptine. The results indicate a marked reduction of the amino acid metabolism in prolactinomas amounting to 60%. These tumors at a later time responded with tumor shrinkage. Hormonally inactive tumors showed no effect of treatment.
Bergström
M
M
Department of Neurorology, University Hospital, Uppsala, Sweden.
Muhr
C
C
Lundberg
P O
PO
Bergström
K
K
Lundqvist
H
H
Långström
B
B
D000236:Adenoma / Q000000981:diagnostic imaging / Q000378:metabolism*; D000596:Amino Acids / Q000378:metabolism*; D006801:Humans; D010911:Pituitary Neoplasms / Q000000981:diagnostic imaging / Q000378:metabolism*; D014055:Tomography, Emission-Computed
D000596:Amino Acids