DISCRIMINANT-ANALYSIS OF PRE-OPERATIVELY AND INTRAOPERATIVELY DETECTED PROGNOSTIC FACTORS INFLUENCING LYMPH-NODE INVOLVEMENT IN PATIENTS WITH COLORECTAL-CARCINOMA

BACKGROUND/AIMS:The aim of this study was to establish whether, and to what extent, pre-and intraoperatively detected characteristics (demog raphic, anamnestic and laboratory data) and tumor characteristics can be used in the assessment of regional lymph node involvement in patien ts with colorectal carcinoma. The assessment also included the number of lymph nodes involved in patients with positive lymph nodes. Conside ring that the number of obtained lymph nodes widely varies in resected specimens, assessment parameters also included the percentage of the involved lymph nodes within the total population of lymph nodes.METHOD OLOGY: From 1992-1993, 46 patients with carcinoma of the rectum and si gmoid colon were studied, with a total number of 736 lymph nodes evalu ated. Out of the total number of lymph nodes, 577 (78.4%) were benign and 159 (21.6%), malignant. Data were analyzed by multi-variant statis tical methods, namely: discriminant analysis and multiple regression w ith the aid of SPSS/PC+ software. RESULTS: For this patient group, we evaluated the following potentially predictive factors for lymph node involvement: age; serum hemoglobin, albumin and alkaline phosphatase l evels; weight loss; and the primary tumor localization characteristics : histologic type, macroscopic growth pattern and depth of tumor invas ion of the bowel wall. We found that there was no difference in the pr ediction of regional lymph node involvement between analysis of the af ormentioned parameters and analysis of the isolated discriminators onl y. CONCLUSION: A predictability likelihood of 83.78% greatly surpasses the acceptable error tolerance level of 5%. Correlation of demographi c, anamnestic and laboratory data about the patient and the characteri stics of the primary tumor cannot be used in distinguishing malignant lymph nodes from benign ones. These data cannot be the basis for exact intraoperative staging and thus cannot be significant criteria for de cision-making about operative treatment modalities.