An apparatus includes a body, a shaft assembly, a stapling head assembly, and an anvil. The stapling head assembly includes an annular deck member, a plurality of staples, and a driver. The deck member includes a deck surface that has a curved profile defined by a curve extending from the inner diameter of the deck member to the outer diameter of the deck member. The deck member further includes an outer array of staple openings and an inner array of staple openings. The driver is operable to drive the staples through the staple openings. The anvil is operable to compress tissue against the first deck surface.