Serial CEA levels in colorectal carcinoma on adjuvant immuno (chemo) therapy

Combined ultrasounds and CEA in preoperative assessment of hepatic metastases from gastrointestinal malignancies

A consecutive series of 100 patients affected by gastrointestinal malignancies entered a prospective controlled study of liver metastases performed by ultrasound echography, CEA, hepatic enzymes (only alkaline phosphatase (AP) was found to be somehow significant). Laparotomic inspection and palpation were taken as objective control of ultrasound scan. Eighteen out of the 100 patients showed diffuse hepatic metastases at surgery (all controlled histologically). Hepatic echography correctly diagnosed liver metastases in 15 out of these 18 patients (= 83.8% sensitivity); two more cases (hepatic fibroangiomas) were interpreted as metastases (= 89.9% specificity). CEA-RIA assay was pathologic (greater than 10 ng/ml) in all of the 18 patients with liver metastases; 21 out of the 82 without liver metastases were CEA positive (difference of mean values statistically significant at P less than 0.01). The only significant hepatic enzyme was AP, which was pathologic in 12 out of 18 patients with liver metastases. The comparative evaluation of the three tests showed that ultrasound scanning missed three cases of diffuse hepatic metastases, which, however, were CEA positive, while AP could not help to correct such misdiagnosis.

Biologic markers in cancer diagnosis and treatment

We have reviewed several tumor markers that our advocates feel are now clinically useful, involve current assay technology, and are based on already available information. These include, in selected instances, estrogen receptors for breast cancer, thyrocalcitonin for medullary cancer of the thyroid, prostatic acid phosphatase for cancer of the prostate, alpha-fetoprotein for hepatocellular cancer, and carcinoembryonic antigen for monitoring colon cancer. We have considered the potential use of measurement of serum proteases and protein degradation products due to their activity as possible future areas of development, and we have explored measurement of tissue aryl hydrocarbon hydroxylase to identify populations at risk of cancer resulting from chemical carcinogenesis. It is clear that the study of tumor markers is already improving patient care in some specific areas and offers exciting potential for the future.

Correlations between serial CEA levels and surgery in patients with colorectal carcinoma

Nowadays the evaluation of serial carcinoembryonic antigen (CEA) levels represents an important parameter for the prognosis of patients with carcinoma of the large bowel. Changes in CEA values allow the drawing of conclusions regarding the effectiveness of therapy. We have studied 63 patients with colorectal carcinoma that underwent surgical treatment. Serial CEA levels were tested in each patient before surgery and 15 days after. The 53 patients were considered surgically cured; and among these 7 did not have a significant decrease of CEA values after surgery. The percentage of recurrences among these patients has been 71.4%; meanwhile patients who showed a decrease of CEA values below cutoff values had recurrences only in 17.3% of cases. For this reason is our opinion that patients considered surgically cured who have postoperative high CEA levels cannot be considered really cured from a biological point of view.

Serial CEA levels in colorectal carcinoma on adjuvant immuno(chemo)therapy--further follow-up. Modulation of adjuvant treatment

Serial plasma CEA levels have been studied preoperatively (testing A); one day after surgery (B); 10--15 days after surgery (C); 4 (D), 8 (E), 12 (F), 16--18 (G), and 22--24 (H) months after surgery in a series of 45 patients affected by colorectal carcinoma who started soon after surgery a protocol of adjuvant immuno(chemo)therapy with Levamisole and BCG. Postoperative follow-up was from one to 26 months, with 28 patients followed for at least one year. Fourteen patients had recurrences: two of these had false-negative CEA tests, three had persistent high CEA levels after surgery, nine had increasing levels 9--12 months before clinical recurrence; and nine of these 14 patients showed frankly pathologic preoperative plasma CEA levels. Six patients who did not have a recurrence but (both at clinical and instrumental evaluation) who had two consecutive high plasma CEA levels, were put on prophylactic polichemotherapy. The prognostic importance of CEA levels both pre- and postoperatively, the possibility of "modulating" postoperative adjuvant treatments on the basis of CEA levels, and the problem of unexplained fluctuations of plasma CEA levels with the putative metabolic linkages are discussed.