Overall and net survival of patients with sarcoma between 2005 and 2010: Results from the French Network of Cancer Registries (FRANCIM).

Background: Sarcomas are rare, heterogeneous, ubiquitously localized malignancies with many histologic subtypes and genomic patterns. The survival of patients with sarcoma has rarely been described based on this heterogeneity; therefore, the authors' objective was to estimate survival outcomes in patients who had sarcomas using the 2020 version of the World Health Organization classification of soft tissue and bone tumors.

Methods: Patients older than 15 years who had incident sarcoma diagnosed between 2005 and 2010 were extracted from 14 French population-based cancer registries covering 18% of the French metropolitan population. Vital status for each patient was actively followed up to June 30, 2013. Net survival (NS) was estimated using the unbiased Pohar-Perme method.

Results: Overall, 4202 patients were included. NS declined with increasing age at diagnosis. According to topographic groups, large 5-year NS disparities were observed, ranging from 47% among women with gynecologic sarcomas to 89% among patients with skin sarcomas. Patients with soft tissue, bone, and gastrointestinal sarcomas had 5-year NS rates of 53%, 61%, and 70%, respectively. Similar heterogeneity was observed according to histologic subtypes, with 5-year NS ranging from 19% for patients with angiosarcomas to 96% for patients with dermatofibrosarcomas. Patients with sarcoma who displayed missense mutations had a better 5-year NS (74%); those with MDM2-amplified sarcomas had the worst NS (45%).

Conclusions: NS rates in patients with sarcoma are presented here for the first time based on the 2020 World Health Organization classification applied to population-based registry data. Large prognostic heterogeneity was observed based on age, topographic and histologic groups, and genomic alteration profiles, constituting a benchmark for future studies and clinical trials.