BACKGROUND.
Cancer patients with single tumors live longer today due to earlier detection and improved treatment methods. For this reason, the authors see more patients who develop a second primary tumor. The etiology of the second tumor can be the same as the first, whether treatment-induced or unknown. The prognoses of these patients usually depend on the behavior of the second tumor.
METHODS.
The authors investigated the lymphocyte subset in 88 of the more than 750 patients listed in the tumor registry at their treatment center who had at least one carcinoma of the breast or colon and a second primary of the same or another site. Mononuclear cells were obtained from heparinized blood by the standard fractionation Hypaque gradient centrifugation technique. Helper and suppressor cells were identified by using three murine monoclonal antibodies: CD3 for mature T lymphocytes, CD4 for helper inducer cells, and CD8 for suppressor cytotoxic cells. T-cell subset distribution was evaluated with flow cytometry.
RESULTS.
Most values of CD3, CD4, and CD4/CD8 were lower in patients than in healthy controls. The values of CD4 and CD4/CD8 were lower in patients who had a second tumor in the colon rather than in the breast.
CONCLUSIONS.
As tumors in patients with a second primary sometimes recur or the patient develops a third primary, the authors are prospectively following their patients to see whether those with immunosuppression have a greater tendency to develop recurrent disease or a third primary.