by Harwood Academic Publishers GmbH Printed in Malaysia

Twenty patients received transduodenal sphincteroplasty and transampullary septectomy between 1987 and 1993. Seven patients had post-cholecystectomy pain which was much improved or abolished in 5 of 7 patients at a mean follow-up of 4 years and 5 months. Four of five patients with chronic pancreatitis were improved at 3 years and 2 months. Three of five patients with recurrent acute pancreatitis were improved at 4 years and 5 months. One of three patients with chronic abdominal pain of hepatobiliary origin was improved at 3 years. Transduodenal sphincteroplasty and transampullary septectomy can relieve pain in patients with post-cholecystectomy pain, recurrent acute pancreatitis, chronic pancreatitis, and chronic abdominal pain of hepatobiliary origin, presumably by improving drainage of the obstructed ducts.


INTRODUCTION
Somatostatinoma is a neuroendocrine neoplasm de- rived from the D cells of the APUD system firstly described by Pearse1.This tumor is rare and the duo- denal location has been described in less than 10 cases.Unlike pancreatic somatostatinoma, described in the late 70's2'3, which generally produces a clinical syn- drome (diabetes, steatorrhea, hypochloridria, dyspepsia), duodenal somatostatinoma may be completely asymptomatic.
We report a case of silent duodenal somatos- tatinoma with hepatic metastases that has been treated by chemotherapy obtaining a surprisingly steady response.

CASE REPORT
The patient was a 43-year-old white woman with a pancreatic pseudocyst previously treated with a cysto- jejunostomy and a Y-en-Roux gastro-enterostomy and a past history of NANB viral hepatitis.She suf- fered from dyspepsia for about 1 year.Some months prior to admission the patient had undergone a gas- troduodenoscopy because of the onset of post-prandial vomiting and epigastric pain radiating to the back.The endoscopist noticed a patent gastro-enterostomy and a marked dilatation of the duodenal bulb due to a stenosis in the second part of the duodenum.
On admission, the physical examination was com- pletely negative.The general condition and the nutri- tional status were good.Routine blood analysis showed abnormal liver function tests (elevated alkaline phosphatase, SGPT and SGOT) and a mild anemia (Hb 12.7 g/dl); tumor markers (CEA, CA 19-9, CA 50, CA 125) were normal.A further endoscopy confirmed the duodenal stenosis and a biopsy was obtained; the histology suggested a neuroendocrine neoplasm and immunohistochemistry was positive for somatostatin, NSE and chromogranin.A plasma somatostatin level obtained was 285 pg/ml (normal range 70-150 pg/ml); urine 5-hidroxyindolacetic acid was slightly increased.
Abdominal US showed two slightly hyperechogenic lesions (15 and 22 mm, respectively) with hypoechogenic edges in the right hepatic lobe and a solid, hypodense mass (3 cm in diameter) located medially and next to the duodenum.
A CT scan (Fig. 1) revealed duodenal dilatation with a mass protruding into the visceral lumen; hepatic masses showed an angiomatous appearance after the injection of contrast medium.A selective angiography of the celiac artery and its branches (Fig. 2) noticed a hypervascularized mass in the second part of the duodenum, containing micro arterovenous fistulae with stasis of the contrast medium; one ofthe hepatic lesions in the fight lobe had a pathologic vascular appearance but not of an angiomatous type.
At laparotomy, multiple bilateral hepatic metastases were found.Frozen sections revealed metastases of apudoma and definitive immunohistochemistry (Fig. 3) confirmed the diagnosis of somatostatinoma.
The postoperative period was uneventful.Before dis- charge, the patient underwent a 1311-MIBG scintiscan to evaluate the usefulness of radiometabolic therapy; the images obtained showed a dishomogeneous uptake which contraindicated nuclide treatment.
In the following months, ambulatory chemotherapy was given (calcium L-folinate 100 mg/m 2 and 5-FU 370 mg/m 2 i.v. for 5 days every 28 days, and e-2b- Interferon 3,000,000 U subcutaneously on alternate days without interruption) for 8 cycles.
The comprehensive evaluation of the response to the therapy showed steady disease lasting 8 months.Infact, a further abdominal US revealed, 9 months after sur- gery, increased diameter of the hepatic metastases and chemotherapy was discontinued.
The patient is alive 24 months after diagnostic laparotomy; she is in good conditions and does not complain of clinical symptoms of somatostatinoma syndrome.She has undergone two further US scans that have not shown any further growth of the hepatic lesions.The levels of urine 5-hidroxyindolacetic acid and plasma somatostatin were in the normal ranges.

DISCUSSION
Somatostatinoma has been more frequently observed in the pancreas, 45% of the described cases were located there.Duodenal location, first reported in 19794,5 is rare and accounts for 19% of the overall literature.This neoplasm may produce a clinicalsyn- drome including diabetes, steatorrhea, hypochlorhid- ria and dyspepsia; cholelithiasis and anaemia have also been described6.However, it should be mentioned that in a recent review 7 no symptoms were specific enough to be considered as pathognomonic.
Duodenal somatostatinoma is hormonally "silent" in most cases8.High levels of other hormones (calcitonin, insulin, Pancreatic Polypeptide, VIP, ACTH, 5-HIAA) have been described in plasma or as cell immunoreactivity.The expanding neoplasm produces symptoms of alimentary tract obstruction (dyspepsia, duodenal stenosis, obstructive jaundice) so it may be Figure2 Selective angiography of the celiac artery and its branches: a hypervascularized mass in the second part of the duo- denum is evident.The neoplasm contains micro-arterovenous fis- tulae with stasis of the contrast medium.undistinguishable from the more common adenocar- cinoma.In our case, the previous surgery for pancre- atic cyst may have been misleading in diagnostic evaluation.Moreover, diagnostic imaging techniques such as US, CT scan and endoscopy do not seem, in our experience, to give specific, results.
A rise in circulating levels of somatostatin follo- wing intravenous infusion of calcium and pentagastrin has been described 9 as a diagnostic test in patients affected by a "non functional" somatostatinoma, but is should be considered that this technique has been employed in already diagnosed cases, so its use as a "true" diagnostic tool seems questionable if there are not further elements suggestive of a somatos- tatinoma.Possibly because of slow growth and non- specific symptoms, the diagnosis is often late, and metastases have been observed in 88% of cases of somatosatinoma7.Tumor spread frequently affects the liver (42%), as in our patient; other common sites involved are regional lymphnodes (39%) and the duodenum.
When technically feasible, surgical treatment seems to be the only effective therapy for this type of neo- plasms; the most suitable procedure is a duodenopancreatectomy.
The role of adjuvant therapy is still debated, because of the paucity of reported experiences.However, a single more effective agent has not been defined to date, chemotherapy seems to be-as in our case-an useful tool for prolonged control of distant meta- stases 6, 7,1 o, 11.

CONCLUSIONS
Somatostatinoma is seldom diagnosed preoperatively: physical examination, clinical symptoms and imaging techniques do not give specific results.Duodenal types are generally asymptomatic from the hormonal aspect and may not produce, as in the case we reported, high levels of circulating somatostatin.
The prognosis of resectable somatostatinoma is much better than that described in pancreatic and biliary adenocarcinomas, so the main goal is to achieve, mainly with immunohistochemistry, a correct diagnosis, in order to plan effective surgery.Cytotoxic therapy may be given in diffuse neoplasms with acceptable results.

Figure
FigureAbdominal CT scan showing duodenal dilatation with a mass protruding into the visceral lumen.

Figure 3
Figure 3 Microphotography of the intraoperative biopsy of liver metastasis (immunohistochemistry with somatostatin antiserum).