Imaging with radiolabeled somatostatin (SST) analogs has recently been esta
blished for the localization of various human SST receptor (hsstr)-positive
tumors, including neuroendocrine tumors, lymphomas, and non-small cell lun
g cancer (NSCLC). Methods: In-111-1,4,7,10-tetraazacyclododecane-N,N',N",N"
'-tetraacetic acid-lanreotide (DOTA-LAN) scintigraphy (150 MBq; 7 nmol per
patient) was performed on 47 patients (28 patients with primary tumors, 19
patients with lung metastases from other tumors) to evaluate the tumor bind
ing in patients with histologically confirmed lung cancer. A group of 27 tu
mor patients without documented lung lesions served as the control group. E
arly and delayed planar and SPECT images were acquired. Whole-body scintigr
aphy was performed at 0.5, 4-6, 24, and 48 h after injection for tumor dose
estimation. In addition, hsstr subtype expression and radioligand binding
characteristics were studied in vitro using lung tumor samples (n = 15). Re
sults: In-111-DOTA-LAN indicated the primary lung tumor in 16 of 16 NSCLC p
atients. Lymph node metastases were visualized in 6 of 6 NSCLC patients, an
d bone metastases were seen in 3 of 3 NSCLC patients. In-111-DOTA-LAN scint
igraphy indicated lung carcinoid in 5 of 5 patients and small cell lung can
cer lesions in 6 of 6 patients. Multiple lung metastases were shown in all
6 patients with non-Hodgkin's lymphoma and in the 1 patient with Hodgkin's
disease, 5 of 5 colorectal adenocarcinoma patients, 4 of 4 carcinoid patien
ts, 2 of 2 neuroendocrine carcinoma (NEC) patients, and 1 of 1 angiosarcoma
patient. Pulmonary tumor sites not indicated by CT or MRI were visualized
in 6 of 47 tumor patients (i.e., 13%; lung metastases in 1 carcinoid patien
t and I NEC patient, lymph node metastases in 1 carcinoid patient and 2 NSC
LC patients, bone metastases in 1 carcinoid patient). The estimated lung tu
mor dose ranged between 0.2 and 5 mGy/MBq. Focal lung uptake of In-111-DOTA
-LAN was not observed in any of the 27 control patients. In vitro binding s
tudies indicated high-affinity binding sites for In-111-DOTA-LAN in NSCLC s
amples (dissociation constants, 0.5 and 4 nmol/L) with predominant expressi
on of hsstr4. Conclusion: In-111-DOTA-LAN yields high tumor binding for var
ious human lung tumors. Consecutively, radiopeptide therapy may offer a pot
ential new treatment alternative for some lung tumor patients.