This phase IV trial evaluates how well giving standard of care (SOC) peptide receptor radionuclide therapy (PRRT) after SOC surgical removal of as much tumor as possible (debulking surgery) works in treating patients with grade 1 or 2, somatostatin receptor (SSTR) positive, gastroenteropancreatic neuroendocrine tumors (GEP-NETs) that have spread from where they first started (primary site) to the liver (hepatic metastasis). Lutetium Lu 177 dotatate is a radioactive drug that uses targeted radiation to kill tumor cells. Lutetium Lu 177 dotatate includes a radioactive form (an isotope) of the element called lutetium. This radioactive isotope (Lu-177) is attached to a molecule called dotatate. On the surface of GEP-NET tumor cells, a receptor called a somatostatin receptor binds to dotatate. When this binding occurs, the lutetium Lu 177 dotatate drug then enters somatostatin receptor-positive tumor cells, and radiation emitted by Lu-177 helps kill the cells. Giving lutetium Lu 177 dotatate after surgical debulking may better treat patients with grade 1/2 GEP-NETs.

The primary objective of this study is to assess the safety and tolerability and to determine
the recommended Phase 2 dose (RP2D) of E7386 in combination with other anticancer drug(s).

This phase II trial tests whether nivolumab and ipilimumab works to shrink tumors in patients with liver cancer that has spread to nearby tissue or lymph nodes (locally advanced), has spread to other places in the body (metastatic), or cannot be removed by surgery (unresectable). Immunotherapy with monoclonal antibodies, such as nivolumab and ipilimumab, may help the body's immune system attack the cancer, and may interfere with the ability of tumor cells to grow and spread. Nivolumab and ipilimumab may be effective in killing tumor cells in patients with liver cancer.