Sixteen. A time of high school activities, beginning college plans and perhaps even dating. Stefanie Renkema was doing none of these things. After an injury on the basketball court while playing her favorite sport, Stefanie was experiencing pain in her lower back/ tailbone area. The continuing pain led Stefanie to her local doctor. Scans and biopsies later, Stefanie was diagnosed with a giant cell tumor, benign but aggressive, in her sacrum.