123I-labelled vasoactive intestinal peptide receptor scintigraphy in patients with colorectal cancer

Abstract

Colorectal cancer is among the leading causes of cancer death worldwide and accounts for about 10% of all cancer deaths. It is second only to lung cancer in men and to breast cancer in women. and it is estimated that 1 in 20 persons is affected in Western countries (Boring et al. 1994: de Cosse et al. 1994: Seidman et al. 1985. The only curative therapeutic option is surgical resection, whereas oncological intervention in patients with advanced. inoperable cancer remains palliative at best (Scheithauer et al. 1993). Because of the strong association between early detection of primary/relapsing tumours or metastases and prognosis, exact determination of the tumour burden is important for the clinical management of these patients. Imaging methods available include endoscopy. ultrasound, barium enema as well as computerized tomography (CT) and magnetic resonance imaging (MRI). Although these methods have specific roles in the evaluation of patients with colorectal adenocarcinoma, none of them fuilfils the criteria of being an 'optimal' approach (Stevenson. 1994) as peritoneal carcinosis or small extrahepatic lesions mimicking postoperative scars (Schlag et al. 1989) might escape detection. Therefore, the evaluation of additional methods for imaging colorectal neoplasms and metastases is warranted.

Gut Peptide Receptor Expression in Human Pancreatic Cancers

“…45,46 In addition, using nuclear medicine scintigraphic techniques, radiolabeled VIP has been used in patients with colon and pancreatic cancers to detect the presence of VIPR. 14,15 Although our data show only a 31% prevalence of VIPR expression in resected pancreatic adenocarcinoma, others have shown this technique to provide more than 90% sensitivity in detecting primary and recurrent metastatic dis- ease. 15 Therefore, receptor scintigraphy using radiolabeled NT or VIP may be particularly useful in the detection of isolated primary or metastatic pancreatic cancers.…”

“…Nuclear medicine techniques using radiolabeled vasoactive intestinal peptide (VIP), for example, have been studied for detection of colorectal and pancreatic cancer. [13][14][15] The possibility of using gut peptide receptors as a focus for treatment or a means of early detection of pancreatic cancer is quite appealing. However, data are required regarding the expression patterns of GI peptide receptors in human pancreatic cancers so that specific receptor-based therapies or detection techniques can be developed.…”

New approaches to therapy of cancers of the stomach, colon and pancreas based on peptide analogs

“…The high density of VIP receptors in colorectal cancers allows their detection with radioimaging [173]. Scanning with VIP radiolabeled with 123 I can visualize intestinal tumors and metastases that express receptors for VIP [174]. In patients with colorectal adenocarcinomas, primary or recurrent tumors were visualized in 10 of 10 cases, and liver metastases in 15 of 18 patients [139].…”

True

“…Thus, GH-RH and its analogues may act through other related receptors. VIP receptors and PACAP receptors were detected in various gastrointestinal tumours (Reubi, 1995;Raderer et al, 1998) and also in human colon cancer cell lines including HT-29 cancers (Lelievre et al, 1998). Antagonistic analogues of GH-RH suppress the stimulatory effects not only of GH-RH but also of VIP on the cAMP production of various cancer cells .…”