An implantable tissue marker device is provided to be placed in a soft tissue site through a surgical incision. The device can include a bioabsorbable body in the form of a spiral and defining a spheroid shape for the device, the spiral having a longitudinal axis, and turns of the spiral being spaced apart from each other in a direction along the longitudinal axis. A plurality of markers can be disposed on the body, the markers being visualizable by a radiographic imaging device. The turns of the spiral are sufficiently spaced apart to form gaps that allow soft tissue to infiltrate between the turns and to allow flexibility in the device along the longitudinal axis in the manner of a spring.