Significance of CT analysis of regional lymph node metastases in colorectal cancer

Purpose: For preoperative staging of colorectal cancer a CT scan is frequen tly performed. This report examines the sensitivity of CT for regional lymp h node metastasis of colorectal cancer using different criteria. Materials and methods: Preoperative CT scans of 153 patients with colorecta l cancer were analyzed using different criteria for N1. The results were th en compared to the post-operative histological findings. Results: For N1=lymph nodes (LN) >1 cm the sensitivity was 47%. For N1=LN > 1 cm or an increased number of LN <1 cm the sensitivity was 71%. In patient s with a primary tumor seen on CT, sensitivity rose to 87%. Discussion: Evidence of regional nodal metastatic disease is on ly relevant for rectal cancer, colon polyps, and for locally excised tumors when consi dering present surgical concepts for the treatment of colorectal cancer. In these cases CT analysis using the broadened criteria for N1 proposes a val uable argument regarding possible preoperative radiotherapy or an operative revision.