Locally advanced rectal cancer: A multivariate analysis of outcome risk factors

Background and Objectives: Stages II and III rectal tumors are known as loc ally advanced rectal cancer (LARC) because they are characterized by a high incidence of local and distant relapses and a low probability of long-term survival. Adjuvant treatments have been advocated to ameliorate overall su rvival (OS), local recurrence-free survival (LRFS), and metastasis-free sur vival (MFS) without a univocal beneficial trend. The aim of this study was to identify the independent predictive factors of OS, LRFS, and MFS which c ould best select patients for adjuvant treatment of LARC. Methods: Of 153 rectal cancer cases seen consecutively from 1991 to 1998, w e studied the main clinical and pathological parameters of 73 LARCs. Clinic al and pathological variables were studied by univariate analysis, and inde pendent predictive factors were identified by multivariate analysis. Results: Stages II and III rectal cancer have shown not statistically diffe rent rates of OS, LRFS, and MFS. Factors independently associated with incr easing OS and MFS were low preoperative carcinoembryonic antigen level (CEA ), low number of metastatic lymph nodes, low percentage of metastatic lymph nodes out of the total number of lymph nodes excised, and adjuvant treatme nt. Increased staging and distal resection margins less than or equal to 1 cm were shown to be independent detrimental risk factors regarding OS and M FS, respectively. Independent prognostic factors associated with a reductio n in LRFS were advanced age, Hartman's resection, distal resection margins less than or equal to 1 cm, and fewer than 14 resected nodes. Conclusions: Whereas stage I rectal cancer can be treated with a good proba bility of cure by surgery alone, avoiding adverse effects of adjuvant regim ens, the outcome of LARC appears to be positively influenced by adjuvant th erapies. In LARC, an accurate study of risk factors would be useful to iden tify which subset of patients could be favorably influenced by postoperativ e radiochemotherapy. (C) 2000 Wiley-Liss, Inc.