Somatostatin receptor scintigraphy in cutaneous malignant lymphomas

Background: Lymphoid cells may express somatostatin receptors (SS-Rs) on their cell surface. Therefore radiolabeled somatostalin analogues may be used to visualize SS-R-positive lymphoid neoplasms in vivo. Exact staging is the basis for treatment decisions in cutaneous malignant lymphoma. We considered the possibility that SS-R scintigraphy might offer a clinically useful method of diagnostic imaging in patients with cutaneous malignant lymphoma. Objective: We evaluated SS-R scintigraphy in comparison with conventional staging methods in the staging of cutaneous malignant lymphoma. Methods: We conducted a prospective study in 14 consecutive patients with histologically proven cutaneous malignant lymphoma. SS-R scintigraphy was compared with physical, radiologic, and bone marrow examinations. Lymph node excisions were performed in patients with palpable lymph nodes. Results: SS-R scintigraphy was positive in the lymph nodes in all four patients with malignant lymph node infiltration and negative in the three patients with dermatopathic lymphadenopathy. In two patients, previously unsuspected lymphoma localizations were visualized by SS-R scintigraphy. In only three patients all skin lesions were visualized by SS-R scintigraphy; these three patients had not been treated with topical corticosteroids. SS-R scintigraphy failed to detect an adrenal mass in one patient and bone marrow infiltration in two patients. Conclusion: SS-R scintigraphy may help distinguish dermatopathic lymphadenopathy from malignant lymph node infiltration in patients with cutaneous malignant lymphoma

Somatostatin receptor scintigraphy: Its value in tumor localization in patients with Cushing's syndrome caused by ectopic corticotropin or corticotropin-releasing hormone secretion

purpose: To assess the feasibility of somatostatin receptor scintigraphy for patients with Cushing's syndrome caused by tumors secreting ectopic corticotropin or corticotropin-releasing hormone (CRH). patients and methods: Ten patients with Cushing's syndrome, nine with ectopic corticotropin-secreting tumors and one with a CRH-secreting tumor, were consecutively studied. For comparison purposes, eight patients with corticotropin-secreting pituitary tumors and one patient with an autonomous adrenal adenoma were investigated. In vivo tumor localization was performed for all patients using a radionuclide-coupled somatostatin analog. The results obtained with this technique were compared with those obtained with conventional imaging techniques. For some patients, the clinical effects of octreotide therapy were evaluated. results: Somatostatin analog scintigraphy successfully identified the primary ectopic corticotropin-secreting and CRH-secreting tumors or their metastases, or both, in 8 of 10 patients; in 2 patients with corticotropin-secreting bronchial carcinoids, the tumors could not be visualized. Normal scans were obtained for the 8 patients with corticotropin-secreting pituitary tumors and the one patient with an adrenal adenoma. conclusion: Somatostatin analog scintigraphy can be included as a diagnostic step in the workup of Cushing's syndrome patients with a suspected ectopic corticotropin-secreting tumor or a CRH-secreting tumor

Somatostatin receptor scintigraphy with [111In-DTPA-d-Phe1]- and [123I-Tyr3]-octreotide: the Rotterdam experience with more than 1000 patients

Various tumours, classically specified as either neuroendocrine or non-neuroendocrine, contain high numbers of somatostatin receptors, which enable in vivo localization of the primary tumour and its metastases by scintigraphy with the radiolabelled somatostatin analogue octreotide. In addition granulomas and autoimmune processes can be visualized because of local accumulation of somatostatin receptor-positive activated mononuclear leucocytes. In many instances a positive scintigram predicts a favourable response to treatment with octreotide. It is tempting to speculate that octreotide labelled with an appropriate radionuclide might be used in cancer therapy. The successful application of radiolabelled octreotide in scintigraphy indicates the possible usefulness of other radiolabelled peptides, either native peptides or derivatives of these, in, for example, nuclear oncology. The small size of these peptides, e.g. bombesin and substance P, is of the utmost importance for a relatively fast blood clearance, thus leading to low background radioactivity. In this way peptides are powerful alternatives to (fragments of) monoclonal antibodies, the application of which to scintigraphic localization of specific cell surface antigen-bearing tumours is plagued by slow blood clearance and, hence, high background levels