Eighty-four potential second-look operations based on sequential carcinoembryonic antigen determinations and clinical investigations in patients with recurrent gastrointestinal cancer.

In our study of patients with resected primary gastrointestinal cancer, slope analysis of the post-operatively increasing carcinoembryonic antigen time courses signaled relapse in about 80 percent of the patients up to 12 months before positive clinical diagnosis. In 29 patients, clinical confirmation of the relapse could be obtained only after second-look surgery. Slope analysis generally differentiated localized from metastatic disease and therefore also predicted the site of relapse. A first evaluation of 84 patients with potential cases of second-look operations provided evidence for a significant increase in survival. Recently, the evaluation of individual carcinoembryonic antigen doubling times was used to derive an individual prognosis since doubling times strongly correlated with the survival of untreated patients. On this basis, it was clearly possible to show the benefit of second-look operation, since patients with resectable recurrences exhibited longer survival times compared with patients with similar carcinoembryonic antigen doubling times without treatment. Moreover, the introduction of monoclonal antibodies with increased specificity for malignant states, has facilitated the selection of patients for second-look operation because unspecific carcinoembryonic antigen elevations are less frequent and recurrent disease can be predicted more reliably due to the higher carcinoembryonic antigen increments associated with malignant growth.