Preheat oven to 400 degrees with a rack in top position. Combine pecans, breadcrumbs, sugar, and cinnamon.
Line a baking sheet with parchment, and top with 1 phyllo sheet. Brush phyllo all over with butter, and sprinkle pecan mixture evenly over top. Repeat 4 times. Top with remaining phyllo sheet, and brush with all but 2 tablespoons butter.
Slice pears and apples 1/8 inch thick; discard seeds. Arrange pear and apple slices in a single layer on phyllo, leaving space between fruit and a 1/4-inch border around edges. Brush fruit with reserved 2 tablespoons butter. Sprinkle with sugar, and dust with cinnamon. Bake, rotating sheet halfway through, until phyllo is golden brown and fruit is soft, 28 to 32 minutes. Let cool slightly. Cut into 8 pieces.