Radioimmunodiagnosis of pancreatic cancer disease.

From a theoretical point of view, immunoscintigraphy of exocrine pancreatic cancer offers itself as a promising diagnostic method. However, the actually available clinical and experimental data point out that the indication for diagnostic application in patients with pancreatic carcinoma has to be viewed more critically than in the case of, e.g., colorectal cancer disease. The quality of imaging depends on a lot of factors, such as the cellular antigen expression, the affinity of the MAbs to the corresponding antigens expressed by the cells, tumor vascularization, tumor size, and unspecific background activity as well as on labeling techniques, the kind of antibodies used, and the technical equipment. All these factors may vary from one patient to the other and from one center to the other. In summarizing the available clinical data, we have to state that immunoscintigraphy does not allow early detection of pancreatic cancer and, consequently, does not allow screening for early stages in asymptomatic patients. Even nowadays primary diagnosis and staging should be based on the imaging methods of ultrasound, CT and/or ERCP, and angiography. With respect to detection of local recurrence and especially peritoneal carcinosis, immunoscintigraphy, however, may be superior when compared to the other imaging methods. The potential clinical value for followup and as a preinvestigation to assess the probability of effective MAb treatment has still to be evaluated in prospective clinical studies. Altogether, a lot of experimental and clinical work remains to be done to introduce immunoscintigraphy of pancreatic cancer into clinical practice as a routine method.