Make a Contribution Your gift to the Osteosarcoma Institute will impact our ability to transform lives and improve the life expectancy of relapsed and metastic patients. Donate and Support More ways to contribute To make a tax deductible contribution, please mail checks made out to Osteosarcoma Institute to: 100 Crescent Court Suite 700 Dallas, Texas 75201 To make a tax deductible contribute via Paypal, please click the button below. Donate now The Osteosarcoma Institute (OSI) is a 501(c)(3) public, non-operating foundation, IRS identification 82-2921815. Click here to download a copy of our exemption letter. The OSI is committed to transparency in its investment processes, and to rapid reporting of results.