Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0007112 (prostatic adenocarcinoma)
 2,574 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The discovery of neuroendocrine differentiation in hormone-refractory prostatic adenocarcinoma has opened a potentially new therapeutic approach in this group of patients with a poor prognosis and few effective therapy modalities. Based on previous findings of increased uptake of 11C-5-hydroxytryptophan (11C-5-HTP) in neuroendocrine tumours using the PET technique, this tracer was applied in the study of 10 patients with metastatic hormone-refractory prostatic adenocarcinoma. In three patients, the study was repeated after treatment. An increased uptake of 11C-5-HTP was observed in all investigated skeletal lesions, although the magnitude of the uptake was moderate. The difference between the standard uptake values (SUV) in normal bone and metastatic lesions was significant (p < 0.001). A kinetic analysis of the uptake of 11C-5-HTP demonstrates an increase during the first minutes followed by a wash-out and a stabilization of the tissue/blood ratio at about 2. The Patlak plots demonstrated a gradual increase in the transport rate during the first 20 to 30 min, after which a constant level was observed. The SUV varied between patients and between lesions over time and treatment. The uptake of 11C-5-HTP discriminates metastatic lesions from normal bone and may thus aid in the diagnosis and, potentially, in treatment monitoring of metastatic hormone-refractory prostatic adenocarcinoma. Uptake kinetics are characterized by a wash-out and cannot alone be used as proof of neuroendocrine differentiation in hormone-refractory prostatic adenocarcinoma.
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PMID:Positron emission tomography (PET) with 11C-5-hydroxytryptophan (5-HTP) in patients with metastatic hormone-refractory prostatic adenocarcinoma. 925 30

Position emission tomography (PET) was performed on two patients with hormone-refractory prostatic adenocarcinoma in order to characterize the mechanism behind an earlier observed increased uptake of tracer hydroxytryptophan (5-HTP) in bone metastases. The osseous metastases were investigated with 5-hydroxytryptophan, radio-labelled with 11C in the carboxyl group (5-HTC), and with 5-HTP in order to elucidate in vivo the presence of hydroxytryptophan decarboxylation. An increased uptake, measured as standard uptake value (SUV), in the metastatic lesions was observed using 5-HTP. The uptake varied between lesions. Using 5-HTC a corresponding uptake was observed. The time-activity rates were similar. The congruence in uptake patterns between 5-HTP and 5-HTC in the investigated lesions, demonstrates that decarboxylation of 5-hydroxytryptophan to serotonin is not a dominant factor in the uptake. It was concluded that 5-HTC could be used in vivo to investigate the chemical event of decarboxylation of 5-hydroxytryptophan and provide information about characteristics in metastatic lesions.
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PMID:PET with hydroxytryptophan as tracer in hormone-refractory prostatic adenocarcinoma: evaluation of decarboxylation in vivo. 942 38