(dtpa-phe(1))-octreotide and Thoracic-Neoplasms

Superimposition of SPECT and computed tomography (CT) slices from the thoracoabdominal region was achieved without the use of external markers for 14 studies in 13 patients with endocrine carcinoma. Technical feasibility and clinical validation of this retrospective fusion method were assessed.. Patients had a history of thyroid cancer or of carcinoid tumor. To detect tumor sites, CT scan and dual-isotope tomoscintigraphy were performed, with 99mTc-hydroxymethylene diphosphonate for bone scintigraphy and with 111In-pentetreotide, 131I or 131I-metaiodobenzylguanidine for tumor scintigraphy (TS). A superimposition method previously developed for the pelvic region was adapted to the nonrigid thoraco-abdominal region. CT-bone scintigraphy and CT-TS superimposed images were obtained. Clinical validation of the information obtained from the superimposed images was obtained from surgery or follow-up imaging studies performed after clinical evolution of the disease process.. Reliable and reproducible registration was achieved in all patients. CT-TS superimposed images produced accurate localization of abnormal TS foci. Accuracy was limited primarily by variable relative displacements of the thoracoabdominal organs. For 10 sites in 8 patients, localization and/or characterization obtained from CT-TS images was confirmed by a reference technique. Superimposition enabled the localization of tumor sites that otherwise could not have been suspected from CT alone and allowed the characterization of CT suspicious masses and the confirmation of CT positive sites. Nonspecific tumor TS uptake sites were also localized.. With standard CT and dual-isotope SPECT acquisitions, SPECT-CT fusion is feasible in the thoracoabdominal region without the use of external markers. Fused images were validated in 8 patients for 10 sites. The use of this technique could probably improve the management and care of patients with endocrine carcinoma.

Topics: 3-Iodobenzylguanidine; Abdominal Neoplasms; Carcinoid Tumor; Carcinoma, Medullary; Feasibility Studies; Humans; Image Processing, Computer-Assisted; Indium Radioisotopes; Iodine Radioisotopes; Iodobenzenes; Octreotide; Pentetic Acid; Radiopharmaceuticals; Reproducibility of Results; Retrospective Studies; Technetium Tc 99m Medronate; Thoracic Neoplasms; Thyroid Neoplasms; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

An account is given of the results observed with I-131 MIBG scintigraphy in four patients (1 bladder pheochromocytoma, 3 neuroblastomas) chosen on account of their particular clinical and diagnostic interest from a series of 41 apudoma patients examined by means of this technique. In the first patient, the unusual site of the tumor in the posterior wall of the bladder meant that its detection by I-131 MIBG was only possible after catheterization of the bladder. In the second patient, uptake in the metastasis was only evident after removal of the primary tumor. In the third patient, the scintiscan revealed several metastases (some in bone) not detected by CT. In the fourth patient (congenital neuroblastoma), enhanced uptake accompanied the appearance of high plasma catecholamine and urinary vanillylhandelic acid values, suggesting a functional switch from a nonsecreting to a secreting form. a supplementary In-111 DTPA-Octreotide (OCT) scintiscan of this patient demonstrated the presence of somatostatin receptors on the neuroblasts. Thus, this examination would seem particularly useful for the differentiation of nonsecreting neuroblastomas. Its employment in assessment of the therapeutic capacity of OCT itself is also suggested.

Topics: 3-Iodobenzylguanidine; Adolescent; Adrenal Gland Neoplasms; Child, Preschool; Humans; Indium Radioisotopes; Infant; Iodine Radioisotopes; Iodobenzenes; Neuroblastoma; Octreotide; Pentetic Acid; Pheochromocytoma; Radionuclide Imaging; Thoracic Neoplasms; Urinary Bladder Neoplasms