Background: In the 75 years since an insulinoma was first described, the challenge for the surgeon has been one of localization. The combination of endoscopic ultrasound (EUS) or intraoperative ultrasound and operative palpation has led to nearly 100% success rate at primary operation in experienced institutions. However, 13% of patients at referral centers undergo reexploration, which has an increased morbidity. With more successful localization modalities, the operative failures have become more challenging than ever.
Methods: During the past 35 years, we have treated 118 cases of sporadic insulinoma. Technical advances in EUS have led to preoperative identification of more than 90% of insulinomas. Despite this success we have become increasingly aware of the limitations of EUS in the surgical treatment of insulinoma. We present the pitfalls of 6 recent cases.
Results: The limitations of EUS include the assessment of malignancy, the identification of pedunculated or adjacent lesions, the evaluation of distal pancreatic lesions, and the differentiation of larger homogeneous tumors from surrounding parenchyma.
Conclusions: The surgical challenge in the treatment of insulinomas has transformed from one of localization to one of recognizing the limitations of our current localization modalities. By sharing our experience with recent difficult cases, we guide the surgeon to greater success and the patient to decreased morbidity.