Gastric mucosa shows minimally increased lymphoplasmacytic cells in the lamina propria what does this mean?

It needs further testing to make sure of these findings, This can occur in certain Lymphomas of the stomach too.

This is just a description of the microscopic lining of the stomach. In most instances this is nothing to be concerned about at all. Rarely it could be a sign of some kind of lymphocytic abnormality. it would be worthwhile to discuss with your gastroenterologist, but it sounds as though it will likely turn out not to be of any concern.