Primary cardiac sarcomas: a retrospective study of the French Sarcoma Group.

INTRODUCTION: Primary cardiac sarcomas (PCS) are rare tumours of dismal prognosis. METHODS: Data of 124 patients with PCS referred to institutions of the French Sarcoma Group (FSG) from 1977 and 2010 were reviewed. RESULTS: Median age was 48.8years. PCS were poorly-differentiated sarcomas (N=45, 36.3%), angiosarcomas (N=40, 32.3%), leiomyosarcomas (N=16, 12.9%) and others (N=23, 18.6%). At diagnosis, 100 patients (80.6%) were localised and 24 (19.4%) metastatic. Tumours were located in the right (N=47, 38.8%), left atrial cavities (N=45, 37.2%) or encompassed several locations in nine cases (7.4%). Surgery was performed in 81 cases (65.3%). Heart transplant was performed in five patients. Radiotherapy adjuvant (N=18, 14.5%) or alone (N=6, 4.8%) was performed in non-metastatic patients only (N=24, 19.4%). With a median follow-up of 51.2months, median overall survival (OS) was 17.2months for the entire cohort, 38.8months after complete resection versus 18.2 after incomplete resection and 11.2months in non-resected patients. Radiotherapy was associated with improved progression-free survival (PFS) on multivariate analysis. Chemotherapy was significantly associated with better OS only in non-operated patients but not in operated patients. In non-metastatic patients, surgery (hazard ratio [HR]=0.42, p<0.001), male gender (HR=0.56, p=.032) was associated with better OS and surgery (HR=0.61; p=.076), radiotherapy (HR=0.43; p=.004) and chemotherapy (HR=0.30, p=.003) improved PFS. CONCLUSION: Only surgical resection is associated with a perspective of prolonged survival. Chemotherapy is associated with a better outcome in non-resected patients.

Coregistration of prechemotherapy PET-CT for planning pediatric Hodgkin's disease radiotherapy significantly diminishes interobserver variability of clinical target volume definition.

PURPOSE: To assess the interobserver variability in clinical target volume (CTV) definitions when using registered (18)F-labeled deoxyglucose positron emission tomography (FDG-PET-CT) versus side-by-side image sets in pediatric Hodgkin's disease (HD). METHODS AND MATERIALS: Prechemotherapy FDG-PET-CT scans performed in the treatment position were acquired from 20 children (median age, 14 years old) with HD (stages 2A to 4B) and registered with postchemotherapy planning CT scans. The patients had a median age of 14 years and stages of disease ranging between 2A and 4B. Image sets were coregistered using a semiautomatic coregistration system. The biological target volume was defined on all the coregistered images as a guide to defining the initial site of involvement and to avoid false-positive or negative results. Five radiation oncologists independently defined the CTV for all 20 patients: once using separate FDG-PET-CT images as a guide (not registered) to define CTVa and once using the registered FDG-PET-CT data to define CTVb. The total volumes were compared, as well as their coefficients of variation (COV). To assess the interobserver variability, the percentages of intersection between contours drawn by all observers for each patient were calculated for CTVa and for CTVb. RESULTS: The registration of a prechemotherapy FDG-PET-CT scan caused a change in the CTV for all patients. Comparing CTVa with CTVb showed that the mean CTVb increased in 14 patients (range, 0.61%-101.96%) and decreased in 6 patients (range, 2.97%-37.26%). The COV for CTVb significantly decreased for each patient; the mean COVs for CTVa and CTVb were 45% (21%-65%) and 32% (13%-57%), respectively (p = 0.0004). The percentage of intersection among all CTVbs for the five observers increased significantly by 89.77% (1.99%-256.41%) compared to that of CTVa (p = 0.0001). CONCLUSIONS: High observer variability can occur during CT-based definition of CTVs for children diagnosed with HD. Registration of FDG-PET and planning CT images resulted in significantly greater consistency of tumor volume definition.