[Evaluation of plasma carcinoembryonic antigen (CEA) in patients with head and neck cancer: correlation with tissue CEA staining].

Forty-five patients with head and neck cancer were the subjects of the study. In most cases, plasma CEA was low and could not provide a significant clinical monitor. Two patients with poorly differentiated epidermoid carcinoma had low plasma CEA levels at the pretreatment stage, but after treatment, the levels tended to be higher because of distant metastasis. Tow other cases exhibiting undifferentiated carcinoma of the maxillary sinus at the pretreatment stage had abnormally high plasma CEA levels of 160 ng/ml and 46 ng/ml. These two patients proved the value of the correlation with cancer therapy and recurrence.