The metastasis of rectal cancer

Eight hundred and eighty-six cases of rectal cancer diagnosed and reported to the National Cancer Registry in 1980 were submitted to obduction. Metastases were identified in 46.8%. Liver, lung and bones were affected in 38.7%, 16.1 and 3.5% of cases, respectively. Pattern of metastatic spread was determined by histology, with adenocarcinoma giving rise to blood-borne metastases, mucinous adenocarcinoma producing mostly lymphogenic metastases and signet-ring cell carcinoma spreading in either way. Isolated liver involvement was established in 9% of patients showing liver metastases at radical surgery. The parameter reached 22% when cases of presacral recurrence were excluded. A histologically oriented scheme is suggested to assure complete diagnostic coverage of metastases and to develop a concept for the treatment of liver secondaries. Targeted intraperitoneal and endolymphatic application of cytotoxic agents for the treatment of liver metastases aimed at reduction of extrahepatic dissemination is discussed.