Diagnostic Imaging Testing

This phase II trial tests the accuracy of functional imaging (FFNP)-positron emission tomography (PET)/computed tomography (CT) to predict response to abemaciclib plus endocrine therapy. Abemaciclib is a drug used to treat certain types of hormone receptor positive (HR+), HER2 negative breast cancer. Abemaciclib blocks certain proteins, which may help keep tumor cells from growing. Endocrine therapy adds, blocks, or removes hormones that can cause cancer to grow. FFNP PET imaging is a form of x-ray that uses FFNP as an imaging agent that may provide more precise information about the location of tumors that "light up" with FFNP than a PET scan alone can provide.

This phase I trial tests the safety, side effects, and best dose of ZEN003694 when given together with abemaciclib in treating patients with NUT carcinoma, breast cancer or other solid tumors that have spread from where it first started (primary site) to other places in the body (metastatic) or cannot be removed by surgery (unresectable). ZEN003694 is an inhibitor of a family of proteins called the bromodomain and extra-terminal (BET). It may prevent the growth of tumor cells that overproduce BET protein. Abemaciclib may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth. Giving ZEN003694 and abemaciclib may help shrink or stabilize cancer in patients with NUT carcinoma, breast cancer or other solid tumors.