a tissue marker formed of a biodegradable polymer having drug - delivery capabilities is combined with a sealant that encapsulates the tissue marker and which serves to help anchor the tissue marker against migration . the sealant is delivered to a site in dehydrated form and moisture inherent in tissue at the site expands the sealant . the expanded sealant is formed of a hydrogel and is therefore more compatible to the surrounding tissue than the material of the tissue marker . the sealant and the tissue marker are both bioabsorbed over time .