口腔扁平上皮癌における腫瘍マーカーの combination assay に関する臨床的研究

Abstract

Tumor markers are tumor-mediated substances, but are not specific substances directly produced by the tumor tissue. The use of tumor markers has been accepted as a valuable tool for the diagnosis, prognosis, and treatment monitoring. The tumor markers that have been used in patients with oral squamous cell carcinoma (O-SCC) include carcinoembryonic antigen (CEA), squamous cell carcinoma antigen (SCC), immunosuppressive acidic protein (IAP), and cytokeratin 19 fragment (Cyfra). All of these markers have very low sensitivity in O-SCC and are not useful for clinical purposes. Most authors have measured single tumor markers, and there are very few reports concerning the use of combination assays in which two or more markers were measured simultaneously. Since the most predominant histological type of cancer in the oral and maxillofacial region is squamous cell carcinoma, various tumor markers were determined singly and in combination in patients suffering from O-SCC. Forty-two consecutive patients with O-SCC treated in our department between 1988 and 1992 were entered in the study. Blood specimens were collected after informed consent was received from the patients with O-SCC and oral benign diseases. Four tumor markers were simultaneously measured, including CEA, SCC, IAP, and Cyfra. The results were as follows : 1. The positive rates were 31.0% for CEA, 38.1% for SCC, 52.4% for IAP and 38.1% for Cyfra in patients with O-SCC. Therefore, CEA, SCC, IAP, and Cyfra levels, of which the positive rates were significantly different (p<0.01) from those of control patients with oral benign diseases, were considered to be of diagnostic value. 2. The CEA, SCC, IAP, and Cyfra levels in these cancer patients were found to differ significantly from the levels in patients with a oral benign disease. 3. The sensitivity (81.0%) and accuracy (77.8%) of the combination assay with these four tumor markers proved to be higher than those obtained with individual markers. 4. In these investigations, the determination of CEA, SCC, IAP, and Cyfra serum levels in patients with O-SCC leads to a more accurate diagnosis. This combination assay may prove to be useful for screening of patients with oral cancer and in the early diagnosis of metastases to other organs.