This phase I trial is evaluating a new imaging tracer (68Ga-FAPi-46) with positron emission tomography (PET)/computed tomography (CT) to determine where and to which degree the tracer (68Ga-FAPi-46) accumulates in normal and cancer tissues (the biodistribution) in patients with solid tumors or hematologic (blood) cancers. PET is an established imaging technique that utilizes small amounts of radioactivity attached to very minimal amounts of tracer, in the case of this research, 68Ga-FAPi-46. Because some cancers take up 68Ga-FAPi-46, it can be seen with PET. CT utilizes x-rays that traverse the body from the outside. CT images provide an exact outline of organs and potential inflammatory tissue where it occurs in a patient's body. Combining a PET scan with a CT scan can help make the image easier to interpret. PET/CT scans are hybrid scanners that combine both modalities into a single scan during the same examination.