68Ga‐DOTATATE PET/CT imaging in endogenous hyperinsulinemic hypoglycemia: A tertiary endocrine centre experience

• Published in: Clinical endocrinology (Oxford) 2022-02, Vol.96 (2), p.190-199
• Main Authors: Shah, Ravikumar, Sehemby, Manjeetkaur, Garg, Robin, Purandare, Nilendu, Hira, Priya, Mahajan, Abhishek, Lele, Vikram, Malhotra, Gaurav, Verma, Priyanka, Rojekar, Amey, Dalvi, Abhay, Uchino, Shinya, Rastogi, Shivam, Lila, Anurag, Patil, Virendra, Shah, Nalini, Bandgar, Tushar
• Format: Article
• Language: English
• Subjects: 68Ga‐DOTATATE‐PET/CT,CECT; Computed tomography; Diagnosis; endogenous hyperinsulinemic hypoglycemia (EHH); Hypoglycemia; Insulinoma; Lesions; Localization; Multiple endocrine neoplasia; Neuroendocrine tumors; Pancreas; Positron emission tomography; Radiation therapy
• ISSN: 0300-0664; 1365-2265
• DOI: 10.1111/cen.14586

Objective Literature regarding utility of 68Ga‐DOTATATE PET/CT in insulinoma localization across various subgroups [benign/malignant/multiple endocrine neoplasia‐1 (MEN‐1) syndrome associated] remains scarce. In this study, the performance of 68Ga‐DOTATATE PET/CT was compared with contrast‐enhanced computed tomography (CECT) and 68Ga‐NODAGA‐Exendin‐4 PET/CT (whenever available) in an endogenous hyperinsulinemic hypoglycemia (EHH) cohort. Design Retrospective audit. Patients EHH patients [N = 36, lesions (n) = 49, final diagnosis: benign sporadic insulinoma (BSI) (N = 20), malignant insulinoma (N = 4, n = 14), MEN‐1 syndrome associated insulinoma (N = 9, n = 15), Munchausen syndrome (N = 2) and drug‐induced hypoglycemia (N = 1)] having both preoperative imaging modalities (CECT and 68Ga‐DOTATATE PET/CT). Measurements Per‐lesion sensitivity (Sn) and positive predictive value (PPV) for histopathological diagnosis of insulinoma. Results Sn and PPV of 68Ga‐DOTATATE PET/CT were 67.3% and 89.2%; 55% and 100%; 85.7% and 100%; and 66.7% and 77% for overall EHH, BSI, malignant, and MEN‐1 syndrome associated insulinoma cohorts respectively. Despite having comparatively lower sensitivity in BSI cohort, 68Ga‐DOTATATE PET/CT localized a pancreatic tail lesion missed by other modalities. 68Ga‐DOTATATE PET/CT had comparatively higher sensitivity in malignant insulinoma than BSI cohort. 68Ga‐DOTATATE PET/CT also paved the way for successful response to 177Lu‐based peptide receptor radionuclide therapy (PRRT). In MEN‐1 cases, lower PPV as compared with BSI was due to uptake in non‐insulinoma pancreatic neuroendocrine tumours (Pan‐NET). Conclusions 68Ga‐DOTATATE PET/CT has supplemental role in selected cases of BSI with negative and/or discordant results with CECT and 68Ga‐NODAGA‐Exendin‐4 PET/CT. In malignant insulinoma, 68Ga‐DOTATATE‐PET/CT has an additional theranostic potential. Interference due to uptake in non‐insulinoma Pan‐NET in MEN‐1 syndrome may hinder insulinoma localization with 68Ga‐DOTATATE‐PET/CT.