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.

This phase II/III trial aims to determine the type of chemotherapy that will benefit patients who have had surgery for their stage II or III colon cancer based on presence or absence of circulating tumor deoxyribonucleic acid (ctDNA). In ctDNA positive patients, this trial compares the effect of usual chemotherapy versus mFOLFIRINOX. In ctDNA negative patients, this trial compares the effect of usual chemotherapy versus ctDNA testing every 3 months to determine which approach might be better to prevent colon cancer from returning. Oxaliplatin is in a class of medications called platinum-containing antineoplastic agents. It works by damaging cells DNA and may kill cancer cells. Leucovorin is in a class of medications called folic acid analogs. It works by protecting healthy cells from the effects of chemotherapy medications while allowing chemotherapy agent to enter and kill cancer cells. Fluorouracil is in a class of medications called antimetabolites. It stops cells from making DNA and may slow or stop the growth of cancer cells. Capecitabine is in a class of medications called antimetabolites. It Is taken up by cancer cells and breaks down to a substance that kills cancer cells. Irinotecan is in a class of antineoplastic medications called topoisomerase I inhibitors. It works by stopping the growth of cancer cells. This trial may help doctors determine what kind of chemotherapy to recommend to colon cancer patients based on the presence or absence of ctDNA after surgery for colon cancer.