The rising incidence of atraumatic fractures in patients either with Ewing's sarcoma or osteosarcoma years after chemotherapy revealed a growing population of childhood cancer survivors with a decreased bone mineral density (BMD) possibly due to a long-term effect of the chemotherapy. Therefore we started to screen our patients below 50y of age who were treated for bone malignancies between 1994 and 2009. The first series of measurements included 15 patients – eight Ewing's sarcoma, three female and five male, with a mean age of 18y (±13SD), and seven osteosarcoma, two female and five male, with a mean age of 19y(±9SD). We screened the patients for deficits in their bone status using DEXA (dual-energy-x-ray-absorptiometry) to gain the T-and Z-Scores of the proximal femur and the lumbal spine. Additionally we took blood samples for endocrinological analysis and utilised a questionnaire to scan the patient's liefestyle. The mean time between diagnosis and investigation was 95months (±79SD) in Ewing's sarcoma and 105months (±54 SD) in osteosarcoma. The results of the age and gender matched lumbal measurement (Z-Score) of the Ewing's sarcoma patients showed a reduction of the BMD in six cases (6/8), including three times osteopenia (3/8) and two times osteoporosis (2/8). The osteosarcoma patients presented a BMD-decline in four cases (4/7) with two times osteopenia (2/7) and one osteoporosis (1/7). In the proximal femur six Ewing's sarcoma (6/8) and six osteosarcoma patients (6/7) showed a BMD-decrease including three osteopenic (3/8) and one osteoporotic (1/8) Ewing's sarcoma and four osteopenic osteosarcoma (4/7). We found two cases of pathologic fractures (2/15), one Ewing's sarcoma 29 months after diagnosis with a fracture of the distal femur and the proximal Tibia (1/8) and one osteosarcoma with a fractured distal femur after 72 months (1/7). As presented in our case series osteoporosis after chemotherapy is an underestimated long-term effect of the chemotherapeutic treatment. In our series BMD-reduction seems to be independent of tumour-type and chemotherapeutic agent like MTX.
