Gastro Entrology, Please Advise Us How Toproceed Further

Hello Doctor, My father-in-law is of 59 yrs old. He is residing in chennai. He used to vomit once in every 15 days with right side of the chest pain. He gets tired out easily after vomiting. We consulted a leading Gastro Entrologists in Chennai and initially he asked him to take medicine for 10 days and then asked to take CT scan. Scan Report has the impression that " CT upper abdomen (plain and contrast). Gall bladder is adequately distended. There is a gross irregular thickening of the GB wall mainly at the fundus. Significant pericholecystic fat stranded noted. Wall thickening noted in the duodenal cap. The CDP is prominent with wall thickening noted. Impression: CT features are suggestive of grossly thickened irregular GB wall (screening ultra sound showed an echogenic lesion attached to the fundus of the gall bladder). Please advise us how toproceed further.