Appraisal of selective angiography in localizing islet-cell tumors of the pancreas.

Abstract

In recent years the problem of accurate preoperative diagnosis of insulin-producing islet-cell tumors of the pancreas has been largely surmounted in adults. Newer technics such as the determination of plasma insulin during the intravenous tolbutamide test (3) or after administration of l-leucine, have contributed to accurate differentiation from other causes of hypoglycemia. Treatment of an islet-cell tumor requires surgical extirpation; yet operative identification of the lesion (or lesions) may pose a difficult problem. The adenomas are generally small, in most cases 1-3 cm in diameter. They are frequently buried within the substance of the pancreas and may not be detected by inspection or palpation. Approximately three-fourths of the tumors occur in the body and tail of the pancreas, but they may be situated in any part of the gland, or even in aberrant pancreatic tissue of the duodenum, spleen, omentum, liver, or elsewhere. Moreover, the tumors are multiple in approximately 10 per cent of cases (4). In his search for the lesion the surgeon may be faced with a prolonged eliotomy, extensive mobilization and manipulation of the pancreas, or progressive empirical partial pancreatectomy with serial sectioning. Therefore, preoperative assessment of the number, size, and location of the lesions would be of material assistance. Since islet-cell tumors of the pancreas may be highly vascular, selective angiography offered promise as a means for preoperative identification of their site and number. In 1963, Olsson reported the first angiographic demonstration of such a tumor (5). Baum et al. (1) identified 4 islet-cell tumors by angiography and Rösch and Bret (6) described 3 additional neoplasms. From the isolated successes reported in the literature, however, one gains no idea of the incidence of diagnostic arteriograms in patients with proved lesions. This paper describes our experience with 6 cases. A correlation between the arteriographic success rate and the histology of the tumors is noted, and, from a review of a larger number of cases, the anticipated success rate from angiography is predicted. Method and Materials Pancreatic arteriography was performed in 6 patients subjected to operative removal of 7 islet-cell tumors. Selective celiac and superior mesenteric arteriography was performed by the Seldinger technic, employing a yellow Kifa catheter in most patients. Twenty-five cubic centimeters of 75 per cent Hypaque was selectively injected into the celiac artery in two seconds, followed by serial filming in the anteroposterior and right posterior oblique projections. The filming program was two exposures per second for four seconds, one exposure per second for four seconds, and one exposure every two seconds for twelve seconds. Twenty-five cubic centimeters of 75 per cent Hypaque was then injected into the superior mesenteric artery, with serial filming in the anteroposterior projection, using the previously described program. It must be emphasized that in all cases the arteriograms were of good to excellent quality, and failure to demonstrate the lesions cannot be ascribed to technical inadequacy. The gross description of the tumors in these patients was as follows: Case I (A.W.): A 1 cm diameter purple tumor in the tail of the pancreas of a 19-year old girl. Case II (R.B.): A 3 cm diameter purple lesion deep in the head of the pancreas in a 48-year-old man who had undergone a prior subtotal pancreatectomy. Case III (H.R.): A 1.5 × 2 cm purple tumor in the tail of the pancreas of a 52-year-old woman. Case IV (R.L.): A white nodule, 3 cm in diameter, in the tail of the pancreas, containing some calcification, in a 19-year-old man. In addition, a 2 mm white lesion was present in the body of the pancreas. Case V (R.B.): A tan, ill-defined lesion, 1.5 cm in diameter, in the tail of the pancreas, which interdigitated with normal tissues. Case VI (H.S.): A 1 cm pale tumor in the tip of the pancreas of a 58-year-old woman.