If a patient has an unremarkable abdominal ultrasound, abdominal mri, and chest ct, would that indicate a low risk of cancers, including esophageal?

Such studies might find an area that would lead to further study, if large enough. Many small areas would not be evident.

Imaging studies are not predictive of developing specific diseases in the future, they are only used to find possible evidence of current conditions in their sensitivity range. Studies with negative findings are important in ruling out specific medical conditions, however they may not offer a positive diagnosis for presenting symptoms for which further work up may be needed.