(dtpa-phe(1))-octreotide and Lymphoma

[(111)In-DTPA(0)]octreotide is a radiopharmaceutical with a great potential for the visualization of somatostatin receptor-positive tumors. The overall sensitivity of Somatostatin Receptor Imaging (SRI) to localize neuroendocrine tumors is high. In a number of neuroendocrine tumor types, as well as in Hodgkin's disease, inclusion of SRI in the localization or staging procedure may be very rewarding, either in terms of cost-effectiveness, patient management, or quality of life. The value of SRI in patients with other tumors, like breast cancer, or in patients with granulomatous diseases, has to be established. The development of Peptide Receptor Radionuclide Therapy (PRRT) is expected to stimulate peptide receptor imaging.

Topics: Brain Neoplasms; Breast Neoplasms; Carcinoma, Small Cell; Humans; Indium Radioisotopes; Lung Neoplasms; Lymphoma; Neuroendocrine Tumors; Octreotide; Pentetic Acid; Radionuclide Imaging; Receptors, Somatostatin; Sarcoidosis

Sixty-six patients with a clinical and neuroradiological diagnosis of CNS tumors were evaluated by 111In-octreotide scintigraphy. Planar images were acquired at 2-4 and 24 hours after the injection of 111-185 MBq of 111In-octreotide (Octreoscan, Byk-Gulden). In the positive scans the tumor/non-tumor ratio was evaluated using a standard ROI method, and an uptake index (U.I.) of the lesion was determined. In vitro binding assays were performed on frozen sections from surgical specimens from 17 patients. All 32 meningiomas demonstrated a positive 111In-octreotide scan with a high U.I. Only 13 of 21 gliomas showed a positive scan, but the U.I. was significantly lower (p < 0.001 by "t"-test); one lymphoma showed a faint tracer uptake. All the other histotypes evaluated yielded negative scans. In all cases the receptorial pattern shown by the immunohistochemical staining technique was concordant with the scintigraphic results. 111In-octreotide scintigraphy allowed a differential diagnosis of meningioma versus other CNS tumors in 6 patients (4 neurinomas, 1 brain metastasis of melanoma, 1 lymphoma). In conclusion, 111In-octreotide scintigraphy is a promising tool to evaluate the SS receptorial pattern of CNS tumors and to increase the diagnostic specificity of conventional imaging providing useful information in selected cases for the therapeutic strategy.

Topics: Brain Neoplasms; Central Nervous System Neoplasms; Diagnosis, Differential; Follow-Up Studies; Frozen Sections; Glioma; Humans; Immunohistochemistry; Indium Radioisotopes; Lymphoma; Melanoma; Meningioma; Neurilemmoma; Octreotide; Pentetic Acid; Radionuclide Imaging; Radiopharmaceuticals; Receptors, Somatostatin

Somatostatin receptor scintigraphy with 111In-labeled octreotide was performed in 22 patients with suspected or known malignant lymphoma. The majority of extra-abdominal lesions (21/24 = 87.5%) were correctly localized, however, only one of nine intraabdominal lymphomas could be detected. No significant correlation was found between scintigraphic results and histological type of lymphoma. Metabolic imaging by positron-emission tomography with 18F-labeled deoxyglucose yielded a higher rate of detection of lymphoma manifestations (92% vs 64%) and better tumor contrast. Further prospective studies are needed to establish the clinical relevance of somatostatin receptor scintigraphy in malignant lymphoma.

Topics: Adult; Biomarkers, Tumor; Deoxyglucose; Female; Fluorine Radioisotopes; Fluorodeoxyglucose F18; Glucose; Granuloma; Hodgkin Disease; Humans; Hyperplasia; Indium Radioisotopes; Lymph Nodes; Lymphoma; Lymphoma, Non-Hodgkin; Male; Octreotide; Pentetic Acid; Plasmacytoma; Receptors, Somatostatin; Tomography, Emission-Computed

A wide variety of primary and metastatic human neoplasms express somatostatin receptors (SS-Rs). We evaluated the SS-R status of malignant lymphomas that had been surgically removed from 31 patients by use of in vitro SS-R autoradiography with the SS analog 125I-[Tyr3]-octreotide as radioligand. Of 11 low-grade-malignancy B-cell non-Hodgkin's lymphomas, 10 were SS-R-positive, with a high receptor density restricted to the neoplastic follicles. All of the 8 intermediate-grade lymphomas were SS-R-positive. Of the B-cell lymphomas of high-grade malignancy, 7 out of 10 were SS-R-positive, often with a high density of receptors. One T-cell lymphoma and one Hodgkin's lymphoma were also positive. SS-Rs were of high affinity (KD = 1.2 nM) and specific for bioactive SS analogs. In 4 patients, the lymphomas were localized in vivo by use of gamma-camera scintigraphy after i.v. injection of the SS analog 111In-[DTPA-D-Phe1]-octreotide. Hot spots, identified in all 4 patients, corresponded to SS-R-positive malignant-lymphoma tissue, as confirmed by receptor autoradiography of the surgically removed tumors. Our data show that SS-Rs are valuable pathobiochemical tissue markers and potentially useful in vivo diagnostic tools for human malignant lymphomas.

Topics: Adolescent; Adult; Aged; Autoradiography; Biopsy; Child, Preschool; Female; Humans; Immunohistochemistry; Indium Radioisotopes; Iodine Radioisotopes; Kinetics; Lymphoma; Male; Middle Aged; Octreotide; Pentetic Acid; Radionuclide Imaging; Receptors, Neurotransmitter; Receptors, Somatostatin; Somatostatin