Immunology and colonic cancer: further evaluation of the radioimmunoassay for carcinoembryonic antigen of the human digestive system as an adjunct in cancer diagnosis

Tumor Markers in Serum of Patients with Primary Squamous Cell Carcinoma of the Esophagus

Serum levels of several tumor markers were studied in 96 patients with untreated primary squamous cell carcinoma of the esophagus. Three markers specific for digestive tract malignancies - CEA, CA19.9 and CA50 - and two non organ specific indicators of malignancy - ferritin and TPA - were evaluated. Positivity rates of CAI9.9 and CA50 were very low (4.4 % and 8.6 % respectively); the markers were therefore considered ineffective in the disease. CEA, TPA and ferritin showed a fair positivity rate (27.1 %, 28.1 %, 33.7% respectively); CEA and TPA were directly related to clinical stage, CEA levels being significantly higher in stage IV than in stage III cases (p = 0.016). TPA preoperatory levels were also directly related to a lower survival probability (p = 0.004). CEA showed significantly lower levels in tumors of lower than in those of middle (p = 0.03) and upper esophagus (p = 0.004). TPA showed a similar behaviour with lower levels in tumors of lower than of middle esophagus (p = 0.03). These findings could be due to a bulky metabolism of tumor markers drained via portail vein in the liver. From our data the following conclusions may be drawn: 1) CEA and TPA may be useful in the staging of esophageal cancer as an ancillary tool to assess the extent of the disease; 2) tumor location is an important variable when evaluating blood levels of tumor markers in patients with esophageal cancer.

Tumor Markers in Squamous Cell Carcinoma of Esophagus: Immunometric Assay in Cytosol and Membrane Fraction

Carcinoembryonic antigen (CEA), tissue polypeptide antigen (TPA), ferritin, and the monoclonal antibody-detected tumor-associated antigens CA19.9 and CA50 were measured by radioimmunoassay in tissue fractions of carcinoma and normal esophageal mucosa from 59 patients with untreated primary squamous cell carcinoma of the esophagus. Tumor markers were measured in cytosol (118 samples) and in a membrane-enriched fraction (32 samples). CEA, TPA and ferritin were detected in almost all the cytosol samples evaluated, CA19.9 and CA50 in 66% and 50% of cases respectively. Ferritin was significantly higher in carcinoma than in normal mucosa. The cytosol concentrations of CEA, TPA, CA19.9 and CA50 were not significantly different in carcinoma and normal tissue. Concentrations of CEA, CA19.9 and CA50 in the membrane fraction tended to be higher in normal tissue than in carcinoma, whereas the cytosol-to-membrane ratio was significantly higher in carcinoma. For CEA, CA19.9 and CA50, the phenotypic pattern of the malignant transformation seems to involve a different intracellular distribution rather than a quantitative change. No correlations were found between tissue and serum concentrations of the tumor markers, the former being related to the phenotypic characteristics of the tumor, the latter to the tumor burden.

Carcinoembryonic antigen in amniotic fluid

Carcinoembryonic antigen (CEA), a substance which is known to occur in high amounts in the fetal gut and also in certain tumors of the gastrointestinal tract, has been demonstrated in amniotic fluids from different stages of pregnancy. Radioimmunoassays of CEA in amniotic fluids of 91 normal pregnancies showed a decrease from a mean of 53 ng/ml at 19 weeks to 25 ng/ml at the end of gestation. The CEA activity in amniotic fluid was eluted in the same volume as a standard 125I-CEA on a Sephadex G200 column. Amniotic fluid therefore contains CEA similar in molecular weight to the CEA purified from liver metastases of colonic cancer. Among 17 cases of abnormal pregnancies, CEA elevations were observed in five with anomalous fetuses.

Community compliance with carcinoembryonic antigen: follow-up of patients with colorectal cancer

PURPOSE

The aim of this study was to determine whether recommendations for surveillance carcinoembryonic antigen (CEA) testing in stage II/III colorectal cancer (CRC) are adhered to upon discharge from our cancer center, patterns of care after CEA elevation, and whether differences in outcomes exist between patients who did and did not receive recommended CEA monitoring.

PATIENTS AND METHODS

A retrospective, single-institution chart review was completed at the Cross Cancer Institute (CCI) in Edmonton, Alberta. The Alberta Cancer Registry (ACR) identified patients with CRC diagnosed between January 1 and December 31, 2001. Patients with stage II/III CRC seen and/or treated at the CCI and later discharged to the community with follow-up recommendations based on American Society of Clinical Oncology guidelines were included. Carcinoembryonic antigen monitoring > or = every 4 months for > or = 2 years was deemed acceptable for study purposes.

RESULTS

The ACR identified 152 stage II/III CRC cases meeting inclusion criteria. Eleven patients (7.2%) received the minimum predefined CEA follow-up. Eighty-seven CEA follow-up tests were elevated; only 20 (23%) elevated CEAs were investigated with predefined timely intervention. Twenty-six patients (17.1%) had documentable tumor recurrence. There was no difference in overall survival or time to recurrence between the groups who received and did not receive appropriate follow-up, although small numbers limit the effectiveness of statistical analysis.

CONCLUSION

Post-therapy surveillance is important in CRC management. Our study reveals follow-up recommendations based on best available evidence for interval CEA testing are not followed in the community. These findings suggest the need for review of recommendations and change in management for monitoring discharged patients with stage II/III CRC.

Tumor-associated trypsin inhibitor (TATI) in primary esophageal carcinoma

Esophageal carcinoma has a catastrophic clinical course with a very low 5 year survival rate of 5%. A circulating tumor marker with good specificity and sensitivity would be useful in the management strategy of the disease. So far, no tumor marker effective in esophageal carcinoma has been identified. Preliminary reports suggest satisfactory positivity rates of tumor-associated trypsin inhibitor (TATI) in esophageal carcinoma. We measured TATI levels in 71 patients with primary squamous cell esophageal carcinoma as well as in 30 tissue samples from both carcinoma and normal esophageal mucosa. Detectable TATI levels were not found in tumor tissue samples. The marker showed significantly higher serum levels in patients than in controls, with an overall positivity rate of 28%. TATI levels were significantly lower in patients with a high number of tumor-positive lymph nodes. No relationship was found between TATI and several other clinical and pathological parameters. High TATI levels correlated with a lower probability of overall survival as well as in cases without clinical evidence of lymph node metastases. TATI did not show any relationship with CEA, TPA, ferritin or SCC. The results of the present study suggest that TATI shows a satisfactory positivity rate in esophageal carcinoma, and TATI levels are related to local disease spread and prognosis.

Carcinoembryonic antigen in high risk pregnancies

The significance of carcinoembryonic antigen (CEA) measurement was evaluated in 25 pregnant women with diabetes mellitus, 15 Rh negative sensitized and nine prolonged pregnancies. Another 114 women with normal pregnancy served as controls. Values in maternal and umbilical cord serum and in amniotic fluid did not change appreciably through 24-42 weeks' gestation. No significant difference in maternal serum, cord serum and amniotic fluid CEA values was found between diabetic, Rh negative sensitized and normal pregnancies at the corresponding weeks. Similar findings were obtained in prolonged pregnancies, except the values in amniotic fluid which were significantly higher than in normal pregnancies due to the presence of meconium. These results suggest that the measurement of CEA in high risk pregnancies is not useful in predicting fetal condition.

Tumor markers in carcinoma and premalignant states of the stomach in humans

Tissue sections taken from areas of carcinoma, areas of intestinal metaplasia in stomachs bearing carcinoma are areas of intestinal metaplasia in stomachs showing atrophic gastritis only were examined for eight markers: a tumour-derived colon-specific antigen (tCSA), carcinoembryonic antigen (CEA), alpha-fetoprotein (AFP), pregnancy-specific beta-glycoprotein 1 (SP1), human placental lactogen (HPL), human beta chorionic gonadotrophin (beta-HCG), transferrin (TF) and ferritin (FE). In terms of the number of markers demonstrated in each of the three categories, there is a close similarity between the cells of adenocarcinoma and cells of intestinal metaplasia in cases of cancer, but not to similar metaplastic cells in atrophic gastritis cases. In addition, it appears that the presence of tCSA and SP1 is closely linked to carcinoma, though only approximately half of such cases contain these markers. It would also appear that there are two types of morphologically identical intestinal metaplasia, one related to cancer, the other not. No difference was found between so-called intestinal type and diffuse-type carcinomas.

Carcinoembryonic antigen (CEA) in normal and pre-eclamptic pregnancies (values in maternal blood, amniotic fluid and umbilical cord blood)

Values of carcinoembryonic antigen (CEA) were measured by radioimmunoassay in 100 pregnant women divided into 4 groups. In group 1 (49 normal pregnancies) and 2 (17 pre-eclamptic pregnancies), the estimation of CEA was done in maternal vein blood, umbilical cord blood and in amniotic fluid. In group 3 (20 normal pregnancies) CEA was measured separately in blood of the two umbilical vessels as well as in maternal vein blood. In group 4 (14 pregnancies with small-for-date infants) CEA was estimated in umbilical cord blood. The values in amniotic fluid of normal and pre-eclamptic pregnancies were more than 20 times higher than in the other two compartments. A significant correlation was found between the amniotic fluid and umbilical cord blood values (r = 0.500; P < 0.05), as well as between the values in umbilical artery and vein (r = 0.792; P < 0.001). Thus, it is thought that CEA is transferred from the amniotic cavity to the umbilical cord while a part of CEA perhaps is produced by the placenta. Umbilical cord blood values of small-for-date fetuses do not differ significantly from the normal. On the contrary, significantly lower values were obtained in umbilical cord blood and in amniotic fluid of pre-eclamptic women as compared to the normal, but this finding is not useful clinically because of the large standard deviation.

Problems of spectrum and bias in evaluating the efficacy of diagnostic tests

To determine why many diagnostic tests have proved to be valueless after optimistic introduction into medical practice, we reviewed a series of investigations and identified two major problems that can cause erroneous statistical results for the "sensitivity" and "specificity" indexes of diagnostic efficacy. Unless an appropriately broad spectrum is chosen for the diseased and nondiseased patients who comprise the study population, the diagnostic test may receive falsely high values for its "rule-in" and "rule-out" performances. Unless the interpretation of the test and the establishment of the true diagnosis are done independently, bias may falsely elevate the test's efficacy. Avoidance of these problems might have prevented the early optimism and subsequent disillusionment with the diagnostic value of two selected examples: the carcinoembryonic antigen and nitro-blue tetrazolium tests.

CEA levels in patients with carcinoma of the esophagus

Serum CEA levels were determined serially by the Hansen Z gel technique on 41 patients with carcinoma of the esophagus and compared to 276 controls. Seventy percent of patients with carcinomas of the esophagus had elevated CEA levels. CEA levels greater than 10.0 ng/ml after therapy correlated with significantly shortened survival. CEA appears promising as an indicator of tumor presence in patients with carcinoma of the esophagus.

[Carcinofetal antigens. III. Further carcinofetal antigens (author's transl)]

The occurrance and significance of important carcinofetal antigens other than AFP and CEA are reported. These included the alpha 2 H-protein which is produced in the liver and increases in serum of patients with various tumors, the fetal sulphoglycoprotein antigen FSA from the gastric juice of patients with gastric cancer, the carcinoplacental alkaline phosphatase (REGAN-isoenzyme)which is found in the serum of patients suffering from e.g. bronchogenic, mammary, urogenital and gastrointestinal carcinomas, the beta-S-fetoprotein which is most likely to be identical with C-reactive protein, gamma-fetoprotein, the carcinofetal antigen in glial tumors (CFGA); ectopic production of placental hormones like human gonadotropin, placental lactogen, plasminogen-activators; leukemia-associated antigens. Furthermore, some other less known carcinofetal antigens are mentioned.

Simultaneous determination of plasma and urinary carcinoembryonic antigen levels

The results of simultaneous plasma and urinary CEA levels in 14 patients are described. The aim was to determine whether urinary CEA derived from plasma or arose independently in the urinary tract. The method of reductio ad absurdum is followed. It is assumed that CEA in the urine is derived from plasma, and CEA clearance values for each patient are calculated. These varied widely from zero to a theoretical infinity. On this basis and from previous experimental evidence, it is concluded that urine is independent of plasma CEA. The finding, however, in some individuals of "anti-CEA"-like factor(s) distorting urinary CEA determination makes for some reservations about the safety of the conclusion. It is, however, certain that with the presently available technology, present urinary and plasma CEA values cannot be correlated.