Evaluation of tumor response to targeted therapies in precision-cut slices of human pancreatic neuroendocrine tumors

Abstract

s / Pancreatology Neuroendocrine Tumors (pNET) and ileal carcinoid tumors have different embryologic origin (foregut and midgut respectively). Aims: To report the clinical and pathological features of a patient with syncronous GH secreting pituitary adenoma, primary pancreatic neuroendocrine tumor and ileal (midgut) carcinoid. Patients&methods: A 66 years old manwith acromegaly due to a GHsecreting pituitary adenoma who has been previously treated with surgery and somatostatine analogues, was referred to our center because of the incidental finding at CT-scan of a 8,7 cm round cystic lesion at the pancreatic tail. Reviewing the imaging, was detected also a 3 cm round solid hypervascular lesion in the mesenteric context and a hypervascular lesion in the lumen of the small gut suggesting a midgut carcinoid with lymphnode metastasis. The patient was asymptomatic. A 68Ga-DOTA-NOC PET/ CT showed focal uptake in all three abdominal lesions confirming their neuroendocrine nature. High serum 5HT levels were found while urinary 5-HIAA was normal. Results: The patient underwent a distal splenopancreatectomy, ileal resection together with excision of themesenteric lesion. The histology and immunohistochemical examinations confirmed that the cell pattern of the pancreatic NET (5-HT negative, Ki-67 < 1%) was different from the ileal carcinoid with lymph node metastases. The patient is well 26 months after surgery without recurrence. Conclusion: Syncronous primary neuroendocrine tumor of pancreas (pNET), midgut carcinoid and pituitary adenoma is a very rare association and in this case were MEN 1 unrelated.