Objective: To identify risk factors associated with cancer-specific survival and develop a predictive model for patients undergoing primary hepatic resection for metastatic colorectal cancer.
Background: No published studies investigated collectively the inter-relation of factors related to patient cancer-specific survival after hepatectomy for metastatic colorectal cancer.
Methods: Clinical, pathologic, and complete follow-up data were prospectively collected from 929 consecutive patients undergoing primary (n = 925) or repeat hepatic resection (n = 80) for colorectal liver metastases at a tertiary referral center from 1987 to 2005. Parametric survival analysis was used to identify predictors of cancer-specific survival and develop a predictive model. The model was validated using measures of discrimination and calibration.
Results: Postoperative mortality and morbidity were 1.5% and 25.9%, respectively. 5-year and 10-year cancer-specific survival were 36% and 23%. On multivariate analysis, 7 risk factors were found to be independent predictors of poor survival: number of hepatic metastases >3, node positive primary, poorly differentiated primary, extrahepatic disease, tumor diameter ≥5 cm, carcinoembyonic antigen level >60 ng/mL, and positive resection margin. The first 6 of these criteria were used in a preoperative scoring system and the last 6 in the postoperative setting. Patients with the worst postoperative prognostic criteria had an expected median cancer-specific survival of 0.7 years and a 5-year cancer-specific survival of 2%. Conversely, patients with the best prognostic postoperative criteria had an expected median cancer-specific survival of 7.4 years and a 5-year cancer-specific survival of 64%. When tested both predictive models fitted the data well with no significant differences between observed and predicted outcomes (P > 0.05).
Conclusion: Resection of liver metastases provides good long-term cancer-specific survival benefit, which can be quantified pre- or postoperatively using the criteria described. The “Basingstoke Predictive Index” may be used for risk-stratifying patients who may benefit from intensive surveillance and selection for adjuvant therapy and trials.
The study describes the development of a multifactorial model for quantifying the risk of cancer-specific survival from 929 patients undergoing hepatic resection for metastatic colorectal cancer. Seven independent risk factors were used in the development of the “Basingstoke Predictive Index,” which accurately predicted outcome on a longitudinal basis.
From the *Department of Hepatobiliary Surgery, North Hampshire Hospital, Basingstoke, United Kingdom; and †Department of Biosurgery and Surgical Technology, St Mary's Hospital, Imperial College, London, United Kingdom.
Presented at the 7th World Congress of the International Hepato-Pancreato-Biliary Association, Edinburgh, September 3–7, 2006.
Reprints: Myrddin Rees, MS, FRCS, Department of Hepatobiliary Surgery, North Hampshire Hospital, Aldermaston Road, Basingstoke, Hampshire RG24 9NA, UK. E-mail: firstname.lastname@example.org.