Implantable marker body for breast treatment

A marker body for marking breast tissue, the marker body comprising:

• an at least partially tubular body made from a soft elastic material;
• and multiple radiopaque marker elements, the multiple radiopaque marker elements being carried by the at least partially tubular body,
• wherein the at least partially tubular body is configured to provide minimal resistance to an external, deforming force and return to an original shape of the at least partially tubular body in the absence of the external, deforming force,
• wherein the at least partially tubular body has two free longitudinal ends which are configured to be connected to each other to form an exterior portion of the marker body, the exterior portion defining an outermost diameter of the marker body and encompassing an interior space, and
• wherein the multiple radiopaque marker elements are configured as metal cylinders having a length and a diameter of less than 5 mm and are either inserted into a lumen of the at least partially tubular body or are pressed onto the at least partially tubular body from outside.