当前位置： SCI文献检索 > NUCLEAR MEDICINE AND BIOLOGY期刊下所有文献 > Positron emission tomography (PET) with 11C-5-hydroxytryptophan (5-HTP) in patients with metastatic hormone-refractory prostatic adenocarcinoma.

Positron emission tomography (PET) with 11C-5-hydroxytryptophan (5-HTP) in patients with metastatic hormone-refractory prostatic adenocarcinoma.

Abstract：

: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.

journal_name

Nucl Med Biol

journal_title

Nuclear medicine and biology

authors

Kälkner KM,Ginman C,Nilsson S,Bergström M,Antoni G,Ahlström H,Långström B,Westlin JE

doi

10.1016/s0969-8051(97)00064-4

subject

Has Abstract

pub_date

1997-05-01 00:00:00

pages

319-25

issue

4

eissn

0969-8051

issn

1872-9614

pii

S0969-8051(97)00064-4

journal_volume

24

pub_type

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