Natural history of EGD abnormalities. Fifteen patients who presented with early-stage GML exhibited residual GML on posttreatment EGD biopsy. Pathology review reported no evidence of disease (green circle), atypical lymphoid cells (blue circle), or residual GML (red open circle). Five patients with atypical lymphoid cells subsequently progressed to local failure (patients 2, 3, 4, 5, and 9). Three patients (6, 8, and 14) had pathologic EGD failures that self-resolved with observation alone.