Background: The best management of liver metastases from colorectal cancer is still debated and little is
known about the true impact of treatments on survival.
Materials and Methods: The study involved 122 patients (77 males), aged 64.0 ± 11.0 years (range: 27.8–86.1) at
diagnosis of liver metastatization (synchronous in 59). All underwent chemotherapy and at least one procedure of
radiofrequency ablation; 53 also had partial hepatic resections. Demographics, tumor characteristics and survival
outcomes from liver metastatization were analyzed with univariate and multivariate techniques. This analysis was
performed also taking into account relative survival as the best estimate of specific survival.
Results: The analysis with observed survival selected the categorized number of involved lymph nodes in the colorectal
specimens as the only statistically significant predictor, while the analysis with relative survival also showed site of the
primary tumor (above the sigmoid colon or otherwise) and number of liver metastases as significant factors. The
standardized mortality ratio was 9.673 (95% CI: 7.668–11.663) and a total of 201.85 years of life were lost in comparison
with the survival of the reference population.
Conclusions: The computation of relative survival – better than observed survival – selected a more adequate number of
predictors, making investigation of even limited series of patients with confounding factors reliable. The finding that
prognosis was mainly dependent on the anatomical presentation of the primary tumor and of liver metastases – instead of
treatments – could explain the still contrasting opinions on the role of the available therapies in this field.