Comparison of positive lymph node ratio with an inflammation-based prognostic score in colorectal cancer
S J Moug1, G McColl, S M Lloyd
1Department of General Surgery, Crosshouse Hospital, Kilmarnock Road, Kilmarnock KA2 0BE, UK.
Background:
Two prognostic scoring systems have been proposed in colorectal cancer: the pathologically based positive lymph node ratio (pLNR) and the inflammation-based modified Glasgow Prognostic Score (mGPS). This study compared these two scores with the tumour node metastasis (TNM) staging system in terms of cancer survival.
Methods:
Between 2003 and 2005, 206 patients, of mean(s.d.) age 69·9(10·6) (range 40-95) years, underwent curative resection for colorectal cancer in two centres. Age, sex, primary tumour site and whether radio/chemotherapy was given were recorded in addition to the three scores (TNM stage, pLNR and mGPS). Univariable and multivariable analyses of overall survival were performed.
Results:
Age, rectal cancer, TNM stage, pLNR and mGPS were significant factors in univariable analysis. On multivariable analysis, N category and tumour stage (I-III) were removed from the model, leaving pLNR and mGPS as independent predictors of overall survival: hazard ratio 1·51 (95 per cent confidence interval 1·24 to 1·84; P < 0·001) and 1·56 (1·18 to 2·08; P = 0·020) respectively. C-statistic analysis, used to compare pLNR and mGPS directly, found only pLNR to be significant (P < 0·001)
Conclusion:
This study found pLNR to be the superior prognostic scoring system in determining long-term survival in patients undergoing resection for colorectal cancer.