Insulinoma in pregnancy: a case report and literature review of diagnostic challenges, multidisciplinary management, and therapeutic dilemmas

Background Insulinoma during pregnancy is exceedingly rare, with fewer than 30 cases reported worldwide. Diagnosis is often delayed due to overlapping physiological and gestational symptoms, posing significant risks to both mother and fetus. Case We report a case of a 36-year-old gravida 4 para 2 + 1 woman presenting at 7 weeks’ gestation with recurrent symptomatic hypoglycaemia. She re-presented at 12 weeks’ gestation with persistent neuroglycopenic symptoms and weight loss. Biochemical evaluation demonstrated inappropriately non-suppressed insulin and C-peptide levels during hypoglycaemia, raising suspicion for endogenous hyperinsulinaemia. Ultrasound was non-diagnostic while magnetic resonance imaging identified a 2.3 x 2.5 cm pancreatic lesion consistent with insulinoma. A multidisciplinary team (MDT) approach involving Endocrinology, Obstetrics & Gynecology (Maternal-Fetal Medicine), Hepatobiliary Surgery, and Radiology guided the management. Due to the tumor size and procedural risks during pregnancy, definitive intervention was deferred while medical therapy with octreotide was initiated, achieving partial glycaemic control. The pregnancy was complicated by fetal growth restriction, necessitating delivery at 34 weeks. Postpartum, she underwent endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA), requiring two sessions before achieving glycaemic stabilization. Conclusion This case highlights the diagnostic challenges of insulinoma in pregnancy and underscores the importance of MDT-guided individualized management. It also illustrates the limitations of EUS-RFA and medical therapy, particularly in larger tumors, and raises important considerations regarding fetal outcomes.