Only few patients with osteosarcoma relapse with solitary skeletal lesions as only sign of recurrence. We used the COSS database to learn more about these rare occurrences.

This report covers all patients with high-grade osteosarcoma of the limbs or axial skeleton registered into the COSS database between 1980 and 2003 who developed 1st recurrences as solitary osseous lesions distant from the primary tumour before 01/2005. Patient-, tumour-, and treatment-related variables and outcomes were evaluated.

38 patients (27 male, 11 female) developed solitary osseous recurrences a median of 2.1 years (range:.5 – 14.3) from primary diagnosis. Primary sites had been limbs in 36 and axial in 2, relapses involved axial sites (24), limbs (10), or craniofacial bones (4). Treatment for osseous recurrence included surgery in 28 patients, radiotherapy in 10, and chemotherapy in 27. After a median follow-up of 1.9 years (range:.1–21.2) from 1st recurrence for all 38 patients and 5.5 years (.3–21.2) for 16 survivors (10 of these in continuous 2nd surgical remission), 2- & 5-year overall and event-free survival probabilities were 55% & 34% and 34% & 27%, respectively. A long interval to recurrence (> 1.5 years) predicted for better outcomes (p< .01). For those 21 patients achieving a 2nd complete surgical remission, 2- & 5-year overall and event-free survival probabilities were 81% & 61% and 52% & 49%, respectively, while only 1/17 patients failing to achieve a 2nd complete surgical remission survived beyond 5 years (p< .001) after additional radiotherapy. 14/16 survivors had also received 2nd-line chemotherapy.

1st solitary skeletal recurrences of osteosarcoma seem to have a favourable outcome provided treatment includes complete surgery as part of multimodal therapy. Some presumed bone metastases may rather represent second primary osteosarcomas.

The COSS studies that form the basis of this report were supported by Deutsche Krebshilfe.

Sarcomas are rare malignant tumors of mesenchymal origin and primarily occur in children, adolescents and young adults. With multimodal treatment concepts survival has significantly improved and is now in the range of 60–70 %. Following relapse or metastasis, however, the prognosis still is poor as is also the case for patients presenting with primary disseminated disease. TranSaR-Net aims to develop novel treatment strategies overcoming tumor cell resistance directed against novel targets. To achieve this goal the German pediatric, adolescent and adult sarcoma research groups have formed a collaborative network linking the nationwide and European trial groups with access to over 90 % of all pediatric and adolescent sarcoma patients and a large number of adult sarcoma patients to basic and translational sarcoma research groups. Within TranSaRNet a registry for patients at relapse is established as target cohort for innovative treatment strategies as well as a biomaterial banking network in order to facilitate the availability of tumor and other biomaterial for basic and translational research. A joint bioinformatics platform will integrate existing array data, to standardize laboratory and evaluation procedures and for modeling new theoretical concepts in a joint effort. Within the basic and translational research work packages, the sarcoma research groups in Germany have coordinated their research activities in a joint effort. The basic research work package (WP1) includes projects on genomic (WP1.1) and epigenetic (WP1.2) tumor characterization as well as identification of the tumor initiating cell (WP1.3) and resistance mechanisms (WP1.3 und 1.4), and the identification of new targets in apoptotic pathways (WP1.4, 2.4) and tumor-induced angiogenesis (WP1.5). The translational research work package (WP2) is focused on innovative immunological treatment strategies including sarcoma specific T-cells (WP2.1), dendritic cells (WP2.2), NK- cells (WP2.4) and tumor imaging (WP2.3).

A brief overview of the projects will be provided.

Background: Intensive chemotherapy in sarcoma treatment may lead to weight loss, and in turn reduce dose intensity. A possible correlation between weight loss under treatment and outcome has never been analysed in sarcoma treatment. Ewing sarcoma (ES) patients undergoing intensive non-corticosteroid-containing chemotherapy commonly experience weight loss. The German Paediatric Oncology/Haematology Society (GPOH) Ewing sarcoma trials (CESS, EICESS) registry was analysed with respect to weight loss and outcome.

Patients and Methods: Body weight (BW) both at diagnosis and after a median of 12 courses of chemotherapy was available in 837 of 1549 ES patients, excluding amputees. Changes in BW were calculated as percentage of initial BW; outcome was determined as event-free-survival (EFS) from diagnosis according to Kaplan-Meier. Correlations of BW and outcome and potential confounders like disease stage or tumour volume were estimated uni- and multivariately.

Results: Weight loss was not correlated with inferior outcome: A loss of 10%–20% of BW was associated with a slightly more favourable outcome (3-year EFS 0.64 +/−0.106, N=82) than weight gain of 10%–20% of BW (3-year EFS 0.58 +/−0.098, N=97), p=0.101. Multivariate analyses revealed no confounders interfering with these results.

Conclusions: In 837 ES-patients analysed, weight loss did not correlate with inferior outcome. This should be observed in discussions about tube feeding and/or parenteral nutrition under cytostatic therapy. Future analyses of the prognostic impact of extreme under- or overweight both at diagnosis or under treatment are warranted in order to develop appropriate guidelines. Validity of this observation should be analysed for other solid tumours.

Supported by EC Biomed and Deutsche Krebshilfe