Histologic examination of the lesion in stomach reveal fat-laden cells, likely cause is -
Lipid-laden macrophages (foam cells) are seen in xanthomatosis of the stomach.

Xanthomatosis of stomach

It is characterized by a collection of lipid-laden macrophages (foam cells), forming plaques or nodules.
Gastric xanthomatosis is more common in patients with : -

1. Gastritis
2. Gastric ulcer 
3. Deudenogastric reflux after gastric surgery.
Lymphoma
Post gastrectomy
Signet-cell carcinoma stomach
Atrophic gastritis