학술논문

Technetium-99m RP527, a GRP analogue for visualisation of GRP receptor-expressing malignancies: a feasibility study.
Document Type
Article
Source
European Journal of Nuclear Medicine. 2000, Vol. 27 Issue 11, p1694. 6p.
Subject
*GASTRIN receptors
*TUMOR diagnosis
*POSITRON emission tomography
Language
ISSN
0340-6997
Abstract
Abstract. Gastrin-releasing peptide (GRP) receptor scintigraphy could allow prediction of response to GRP receptor-targeted treatment options, early non-invasive diagnosis and in vivo prognostic stratification of GRP receptor-positive tumours. This study reports on the imaging characteristics and efficacy for tumour detection of technetium-99m RP527, a [sup 99m]Tc chelated targeting peptide derived from bombesin, which binds GRP receptors with high affinity. Ten patients (four men and six women, mean age 56.4 years) either suffering from metastasised prostate (n, number of patients = 4) or breast carcinoma (n=l) or presenting with a clinical diagnosis highly suggestive for breast carcinoma (n=5) were included in the study. In the latter five patients, [sup 99m]Tc-RP527 scintigraphy was performed prior to diagnostic, e.g. biopsy, and staging examinations. Final diagnosis in these patients was breast carcinoma in all five. In all patients, whole-body planar scans and tomographic images were acquired 1 h and 5-6 h post injection of 555 MBq [sup 99m]TcRP527 and tumour to normal tissue (T/N) ratios determined. [sup 99m]Tc-RP527 showed specific uptake in four of six breast and one of four prostate carcinomas. T/N ratios derived from planar and tomographic images increased significantly (P<0.01) from 1.65 (SD 1.53) and 3.35 (SD 3.04) to 2.58 (SD 1.26) and 7.23 (SD 8.46), respectively. T/N ratios derived from tomographic images were consistently higher (P<0.01). The data presented suggest that [sup 99m]Tc-RP527 results in specific tumour localisation and exhibits good imaging characteristics with a good T/N ratio that may be further enhanced by singlephoton emission tomography. [ABSTRACT FROM AUTHOR]