Clinical efficacy of octreotide scintigraphy in patients with midgut carcinoid tumours and evaluation of intraoperative scintillation detection

Abstract

111In-diethylenetriamine penta-acetate-D-Phe1-octreotide scintigraphy was evaluated in a group of 27 patients with disseminated midgut carcinoid tumour. Additional information gained by the intraoperative use of a scintillation detector was studied in five patients with midgut carcinoid tumours and in two with endocrine pancreatic tumours. In 19 patients tumours not recognized by non-invasive radiological methods were visualized in 27 locations, most commonly in liver and para-aortic lymph nodes. Three false-negative tumour locations were noted (ovarian and peritoneal). With guidance from scintigraphic findings, nine patients underwent surgical tumour reduction, leading to complete remission in three. Clinically suspect tumour lesions were measured by the detector in situ, and ex vivo after excision. After excision the tissue:blood activity concentration ratios were calculated. In situ measurements were helpful in the localization of tumours and in the control of adequate clearance of tumour tissue. High tissue:blood activity concentration ratios at 1, 2 and 5 days in the five patients with midgut carcinoid tumour indicate a potential role for radiation therapy with radiolabelled octreotide in patients with somatostatin receptor-positive tumours.

Intraoperative detection of somatostatin-receptor-positive neuroendocrine tumours using indium-111-labelled DTPA-D-Phe1-octreotide

“…The corresponding figure for MTC patients was clearly lower, 65%. In a previous evaluation of the efficacy of scintigraphy in MC patients we found a higher sensitivity than conventional radiology (CT/US) and a high specificity (Ahlman et al, 1994). In the present study T/B ratios varied considerably between the different scintigraphy-positive neuroendocrine tumour types; in MC tumours the ratio was 27-650, in a gastric carcinoid 71-210, in MTC 3-39 and in EPT 910 -1500.…”

“…These high ratios would be expected to facilitate detection of tumours with intraoperative scintillation detection in comparison with, for example, radioimmunoguided surgery using radiolabelled monoclonal antibodies (Curtet et al, 1990;Sardi et al, 1989). Earlier limited studies on probe-guided surgery using radiolabelled octreotide in patients with neuroendocrine tumours (Ahlman et al, 1994;Schirmer et al, 1993;Waddington et al, 1994) have been promising in individual patients. However, in this study in situ measurements with the present detection system (scintillation detector, ligand and isotope) gave lower ratios than expected from the high T/B ratios and thus added limited information to the preoperative scintigraphy and macroscopic findings during surgery.…”

“…By using radiolabelled octreotide ("'In-labelled DTPA-D-Phe'-octreotide or 1231_ labelled Tyr3-octreotide) a sensitive scintigraphic technique for localisation of somatostatin receptor-positive tumours has been developed (Bakker et al, 1991;Lamberts et al, 1990). The high sensitivity and specificity of the scintigraphic method in midgut carcinoid tumours (Ahlman et al, 1994) form the basis of the present study. We have evaluated the use of a handheld scintillation detector for intraoperative localisation of somatostatin receptor-positive tumours in addition to preoperative scintigraphy.…”

Successful receptor-mediated radiation therapy of xenografted human midgut carcinoid tumour

“…In coupled with the somatostatin analogue octreotide via the chelator DTPA (Krenning et al, 1993;Ahlman et al, 1994;Cimitan et al, 2003). Pharmacological treatment of the carcinoid syndrome with long-acting somatostatin analogues reduces hormone release and related symptoms in the majority of patients.…”

Comparative studies on the expression of somatostatin receptor subtypes, outcome of octreotide scintigraphy and response to octreotide treatment in patients with carcinoid tumours

“…The use of long-acting somatostatin analogues, for example octreotide, has become a well-established medical treatment strategy with excellent control of patient symptoms (Gorden et al, 1989). Scintigraphy using [ll1n]DTPA-D-Phel-octreotide has become a valuable diagnostic tool to determine the extent of tumour disease and for planning surgical treatment (Bakker et al, 1991;Ahlman et al, 1994).…”