I. Reisinger et al., SOMATOSTATIN RECEPTOR SCINTIGRAPHY IN SMALL-CELL LUNG-CANCER - RESULTS OF A MULTICENTER STUDY, The Journal of nuclear medicine, 39(2), 1998, pp. 224-227
The aims of this study were to determine the accuracy of somatostatin
receptor scintigraphy in the detection of the primary tumor and its me
tastases in small-cell lung cancer (SCLC) in a large patient populatio
n, and to investigate the course of somatostatin uptake in primary tum
ors during therapy. Methods: In a total of 100 patients, 134 examinati
ons were performed. Twenty-seven of the patients were examined before
and after chemotherapy. Planar whole-body images were acquired 4 hr an
d 24 hr after injection of approximately 200 MBq In-111-pentetreotide.
SPECT of the thorax was performed after 24 hr. Tumor-to-background (T
/B) ratios for the primary tumor were averaged from anterior and poste
rior projections. Results: Compared to conventional investigations, so
matostatin receptor scintigraphy (SRS) visualized the primary tumor wi
th varying degrees of uptake in 96% of the examinations. Regional meta
stases and distant metastases were detected in 60% and 45% of the exam
inations, respectively. The uptake of the somatostatin analog by the p
rimary tumor was significantly lower in the patients examined during c
hemotherapy as compared to those examined before treatment (T/B ratio
= 1.94 +/- 0.79 versus 2.35 +/- 0.9, p < 0.005). A decrease in T/B rat
io was noted in patients with remission at the time of SRS (From 2.40
+/- 1.56 to 1.63 +/- 0.72, p < 0.05). No difference in the pretreatmen
t uptake of octreotide by the primary tumor was identified between pat
ients with tumor progression and those with partial or complete remiss
ion. Conclusion: Somatostatin receptor scintigraphy has a high sensiti
vity in the detection of the primary tumor in SCLC but fails in the de
tection of metastases. Thus, SRS does not provide useful information f
or staging of SCLC. Since somatostatin uptake by the primary tumor is
affected by chemotherapy, it may be used to follow up on the course of
SCLC.