The inflammatory response within Dukes' B colorectal cancers: Implicationsfor progression of micrometastases and patient survival

OBJECTIVES: The aim of this study was to determine the relationship between the inflammatory response in primary colorectal carcinomas, patient outcom e, and the fate of bone marrow micrometastases. METHODS: The populations studied were a) 155 consecutive patients with Duke s' B colorectal cancer and follow-up for a mean of 5 yr, from the Mercy Hos pital, Cork, and b) 260 consecutive patients with rectal carcinoma Dukes' B and follow-up for >10 yr, from St. Mark's Hospital, London. The primary tu mor was assessed for the Jass and "Crohn's-like" lymphoid reactions. In 36 consecutive patients, bone marrow aspirates were examined for micrometastas es before and greater than or equal to6 months postoperatively. RESULTS: The relationship between prognosis and the inflammatory reactivity in the tumors was similar in both populations. In the Mercy group there we re two deaths among 40 patients who had coexistent Jass and Crohn's-like in filtrates. This contrasted with 25 deaths among 58 patients in whom both in filtrates were absent (p < 0.005). Results were intermediate in cases in wh ich either type of inflammatory reaction was present alone. In the St. Mark 's patients similar prognostic differences were sustained for up to 10 yr. Bone marrow micrometastases were present in 12/36 patients preoperatively a nd in 14/36 postoperatively. Seven of 12 patients with preoperative microme tastases were negative postoperatively, indicating clearance of tumor cells . Nine of 24 who tested negative preoperatively had micrometastases postope ratively. The clearance and presence of postoperative micrometastases was r elated to the immunological responses in the primary tumor. CONCLUSIONS: These results demonstrate an association between the inflammat ory reaction, prognosis, and clearance of micrometastases, indicating a sys temic antitumor reaction that confers a survival advantage. (C) 2000 by Am. Cell. of Gastroenterology.