Primary Hepatic Somatostatinoma (G2) With Diabetes and Nodal Metastasis: An Exceptionally Rare Primary Liver Tumor

A 45-year-old woman presented in January 2025 with long-standing polydipsia and weight loss. Contrast-enhanced CT revealed a 103 × 87 mm right-lobe hepatic mass (a), and—after multidisciplinary discussion and patient preference—an open right hemihepatectomy was performed (b). Postoperative pathology showed a well-differentiated neuroendocrine tumor with synaptophysin(+), chromogranin A(+), CD56(+), SSTR2(+), somatostatin(+), and Ki-67 ≈ 10%, consistent with primary hepatic somatostatinoma (G2) (c). According to NANETS criteria, Grade 2 disease was assigned, although metastatic spread could not be fully excluded. Two weeks after surgery, persistent insulin-requiring hyperglycemia prompted further assessment. 18F-AlF-NOTA-octreotide PET/CT demonstrated avid enlarged lymph nodes adjacent to the left iliac vessels (a). Laparoscopic pelvic lymph-node dissection confirmed metastatic involvement with an identical immunophenotype. One week after nodal clearance, the patient's blood glucose normalized (Informed consent was obtained from the patient to publish these images.).