(HealthDay News) – The current staging system and postoperative nomograms, which are based on patient and tumor characteristics and predict prognosis after resection of retroperitoneal sarcoma (RPS), are no longer significant one year after survival, according to a study published online January 13 in Cancer.
Andrea M. Abbott, MD, of the University of Minnesota in Minneapolis, and colleagues retrospectively examined National Cancer Institute-sponsored tumor registries to identify 1,199 patients who underwent surgical resection for nonmetastatic RPS from 1988 to 2007. Conditional survival was defined as time-specific estimates conditioned on surviving a specific number of years following diagnosis. The impact of various factors on sarcoma-specific survival was assessed at baseline and five years after diagnosis.
The researchers found that older age, male gender, histologic subtype, and high tumor grade predicted worse sarcoma-specific survival at the time of diagnosis. Older age, male gender, and histologic subtype were no longer significant predictors of conditional survival after one year of survival. After five years of survival, only high grade tumor remained a significant predictor of worse prognosis (hazard ratio, 1.95).
“This population-based study demonstrates that the factors which are predictive of survival at baseline lose significance after one year of survival,” write the authors.