Tumour lysis as a factor affecting blood levels of CEA.

A hypothesis is proposed that tumour lysis may be an important factor affecting blood levels of CEA. This has been explored in an experimental study with a model tumour system, consisting of immune-deprived mice bearing human CEA-producing tumours. Using agents such as irradiation, chemotherapeutic drugs, diphtheria toxin and techniques such as cryosurgery, it has been shown that tumour lysis is important when it is both rapid and extensive. The extent to which this may occur in patients remains uncertain, except in rare instances of dramatic response of malignant disease to treatment.