Survival analysis
Median follow-up was 5 years, and five-year estimated PFS and OS for the
entire population was 58.4% (95% CI: 49.4 – 69.1%) and 59,1% (95%
CI: 50.5 – 69.3%), respectively (FIG.1). There were no differences
observed between males and females in either PFS (53.8% vs 60.1%;
p=0.58) or OS (58.3% vs 60.2%; p=0.49). Patients with localized
disease [71.0% (95% CI: 60.3 – 83.7%)] had better OS compared to
those with metastatic disease [52.9% (95% CI: 38.7 – 72.4%);
p=0.019]. SR patients (5-year OS: 69.4%) were observed to have higher
OS than HR patients (5-year OS: 53.8%), although this difference was
not statistically significant (p=0.063) (FIG.2). Patients that lived
>40km from INCA (5-year OS: 68,2%) fared better than those
who lived closer (5-year OS 52%; p=0.032) (FIG.3).
Patients treated as per COGA9961 Protocol had better OS (5-year OS:
70.6%) compared to those treated with pre irradiation chemotherapy
regimen (5-year OS: 41.7%), however this difference did not reach
statistical significance (p=0.16). Sixteen patients initially stratified
as SR were treated with higher doses of radiation therapy as per HR
regimen because of the delay in starting raditation therapy. The
survival outcomes were better, but not statistically significant, than
those treated as SR (79.4% vs 67.7%; p=0.22).