The value of liver scan in the follow-up study of patients with adenocarcinoma of the colon and rectum.

Seventy consecutive patients with adenocarcinoma of the colon and rectum had a liver scan followed by surgical exploration of the liver. Preoperatively, blood chemistry studies were done in addition to palpation of the abdomen. Surgical findings were correlated to results of the liver scans, function tests and palpation of the liver. The overall concordance of liver scans with surgical findings was 78 per cent. Thirty per cent had false-positive results and 15 per cent, false-negative results. The correlation of the liver scan with surgical findings was improved with increasing extent of metastases. When less than 25 per cent of the liver was replaced by tumor, there was a random correlation of scan to surgical findings. By combining liver scans and liver function tests, metastases could be predicted with increased reliability only in patients who had severe metastatic disease of the liver. It is strongly recommended that patients with liver scans suggestive of metastatic disease and with most liver function tests within normal limits undergo exploration to establish the diagnosis. Exploratory laparotomy seems to be the only way to avoid chemotherapeutic treatment of patients with false-positive scans and still allow detection and treatment of metastases to the liver to occur at earlier stages.