Endocrine Abstracts

Introduction: Synchronous and asynchronous cases of acromegaly and other malignancies have been reported in literature. However, synchronous apperance of acromegaly and gastrointestinal stromal tumors (GIST) is encountered so rarely. We herein reported a case of synchronous acromegaly and GIST.

Case report: A 59-year-old patient was investigated due to iron deficiency anemia. On the physical examination revealed enlarged hands and coarse facial feature; and, several discrete skin tags were detected. The laboratory findings were as follows: hemoglobin, 8.6 g/dl; hemotocrit, 28.8%; GH, 5.14 ng/ml; and IGF1, 820 ng/ml (normal range: 81–225 ng/ml). Oral glucose tolerance test of 75 g was performed, and GH values were unsuppressed (GH, 3.60 ng/ml at min 0; GH, 4.20 ng/ml at min 30; GH, 4.29 ng/ml at min 60; GH, 4.50 ng/ml at min 90; and GH, 1.80 ng/ml at min 120). Pituitary magnetic resonance imaging revealed a left pituitary microadenoma of 7 mm, and so the case was diagnosed with acromegaly. Endoscopy of upper gastrointestinal tract revealed an ulcerovegetan mass in duedonum. Biopsy was performed, and as a result of the histopathological investigation, a tumoral lesion with spindled-pattern cells with centrally placed nucleus, pale eosinophilic cytoplasms and forming ill-defined fascicles was observed. Immunohistochemical stains indicated the following results as positive ones: CD117 (c-kit), CD34 and vimentin, and negative ones: S100 and desmin. The case was diagnosed with GIST. The patient diagnosed with acromegaly and GIST was operated on due to GIST. After GIST operation, the case was started to be administered with somatostatin analogue to treat acromegaly because of the patient’s refusal of pituitary surgery.

Conclusion: The involvement of IGF system in GIST was indicated in literature. However, the association between acromegaly and GITS is not known exactly.