The prognostic and postoperative monitoring capabilities of the CEA assay were compared to pathological staging of the operative specimens, clinical followup including endoscopy, radiology and scanning techniques, as well as DNCB skin testing and laboratory enzyme determinations (alkaline phosphatase and transaminase). A total of 46 patients with curative resection for colorectal carcinoma were studied. This included 23 patients with recurrent tumors compared to 23 long-term survivors without signs of recurrence at the time of the study. Preoperative CEA determinations were a good prognostic tool comparable to pathological staging of the specimen. Post operative CEA monitoring was the earliest sign of recurrence in 14 of 23 patients and was positive at the time of recurrence determined by other methods in 20; it was negative in only three cases. The incidence of false positive results among the non recurrent group became a lesser problem when repeated elevated values were required before considering the patient as having a recurrence. From these data, it seems reasonable to propose the use of a second-look operation in patients with maintained elevation of circulating CEA and no clinical signs of tumor presence, if we are to treat recurrence at an early stage. Chemotherapy would be an alternative way to deal with this problem, since the absence of clinical signs in general correlate with small bulk of tumor which at this time may be more susceptible to chemotherapeutic agents.

The Gastrointestinal Tumor Study Group (GITSG) has since 1975 included protocols for monitoring carcinoembryonic antigen (CEA) levels in its colorectal cancer adjuvant trials. Among the 563 patients on the colon cancer study (GI 6175) and the 207 patients on the rectal cancer study (GI 7175), one third had preoperative CEA determinations and more than 90% had some postoperative CEA monitoring. Colon cancer patients whose preoperative CEA was greater than 5 ng/ml had a greater probability of recurring than those whose values were lower (33% versus 18% recurrence with 21 months minimum follow-up; p < 0.05). The prognostic value of preoperative CEA was apparent only in patients with Dukes' C1 colon tumors. Preoperative CEA values were not of prognostic significance among the rectal adenocarcinoma patients. Although elevated levels of CEA after resection of either colon or rectum cancers were strongly associated with subsequent tumor recurrence, no single CEA value, arbitrarily defined as "elevated", provided an adequate screening test with both high sensitivity and high specificity. Postoperative CEA elevations were more strongly predictive of recurrence when part of a steadily rising trend. In the colon cancer study, the median monthly increase in CEA for disease-free patients was estimated to be zero, and for the relapsed patients 5.8%. The corresponding estimates for patients on the rectal cancer protocol were zero and 7.8%. Only 36 of the 344 disease-free patients on the colon protocol and 14 of the 94 disease-free patients on the rectal protocol (15%) exhibited a rate of increase of CEA as high as 3% per month over the entire period of observation. Two thirds of the relapsed patients on both studies showed a rate of increase this high or higher. The patterns of CEA rise in individual patients were quite varied, however, and monthly rates of increase as established in our study are not to be used as guidelines in patient management.

Fifty-one evaluable patients with liposarcomas were reviewed. Two-thirds of the patients were referred after local recurrence. One-third with primary surgery at RPMI had local recurrence rate of 31.6%. Overall, one or more local recurrences presented in 78% of patients. Pulmonary metastases, occurred in 45%, while liver metastases in 13.6%. Most common primary sites were the lower extremity, followed by the retroperitoneal area and upper extremity. Median survival is better for upper and lower extremities than other areas (P less than 0.01). The medium survival was longer in the group that received radiation after resection although the difference was not statistically significant. The high rate of local recurrences suggests the adjuvant use of radiation postoperatively when the surgical margins have not been adequate. Sixteen patients are alive and disease-free, with 10 of them having had five years or longer follow-up.

A consensus Development Conference was held at the National Institutes of Health from September 29-October 1, 1980, to address issues concerning the role of carcinoembryonic antigen (CEA) as a marker in the management of cancer. The panel met following formal presentations and discussions to assess the issues based on the evidence presented. These issues included: Should CEA be used in cancer screening? Is CEA helpful in cancer diagnosis? What does CEA tell about the extent and outcome of cancer? Is CEA helpful in monitoring cancer treatment? This paper constitutes the panel's findings.