Medical Management of Well-Differentiated Pancreatic Neuroendocrine Tumors: From Conventional Therapies to Emerging Strategies

Grade 1-2 pancreatic neuroendocrine tumors exhibit considerable biological and clinical diversity, which translates into a broad range of available therapeutic approaches. Given the absence of a universally accepted treatment sequence, treatment selection requires a practical framework based on tumor biology and clinical presentation. Clinical management should be individualized by integrating the histologic grade, disease extent, symptom burden, and somatostatin receptor (SSTR) expression. For patients with low-volume, SSTR-positive, and clinically indolent disease (Ki-67 < 10%), long-acting somatostatin analogues, including octreotide and lanreotide, are commonly used as initial therapies to control hormonal symptoms and delay tumor progression. In patients with radiologic progression requiring systemic disease control, targeted agents such as everolimus and sunitinib represent established subsequent options, particularly when disease stabilization is the primary therapeutic goal. Peptide receptor radionuclide therapy with ¹⁷⁷Lu-DOTATATE has demonstrated meaningful antitumor activity and is generally considered in patients with SSTR-positive tumors with progressive disease (Ki-67 ≥ 10%) or increasing tumor burdens, especially when tumor reduction is desirable. Combination cytotoxic chemotherapy, most notably the capecitabine-temozolomide (CAPTEM) regimen, remains an important consideration for patients with higher tumor burdens or more aggressive tumor biology. This review summarizes current evidence and provides a practical overview of treatment selection and sequencing for the systemic management of Grade 1-2 pancreatic neuroendocrine tumors, while also highlighting emerging therapeutic strategies, including targeted alpha therapy and SSTR2 antagonist-based approaches.