TANDEM Peptide Receptor Radionuclide Therapy Using [225Ac]Ac-/[177Lu]Lu-DOTA-LM3 in a Patient With Parotid Gland Metastasis From Pancreatic Neuroendocrine Neoplasm

We present the case of a young 38-year-old woman with metastatic progressive pancreatic neuroendocrine neoplasm (NEN) exhibiting an unusual metastasis to the parotid gland. After previous treatments, including radionuclide therapy with the somatostatin-receptor agonist DOTATOC and parotid metastasectomy, failed, she was referred to TANDEM peptide receptor radionuclide therapy (PRRT) using the somatostatin-receptor antagonist DOTA-LM3 labeled with Actinium-225 and Lutetium-177. Following 2 cycles of TANDEM-PRRT, she achieved partial remission in all metastatic sites, notably in the parotid gland and liver. This is the first reported case of metastatic pancreatic NEN with parotid involvement treated with TANDEM-PRRT.