“…The presence of elevated levels of serum AFP in some patients with germ cell neoplasms has been noted during the latter part of the last decade (Abelev et al, 1967;Masopust et al, 1968;Mawas et al, 1969) and, more recently, the association between the increased AFP production in patients with germ cell tumours composed of, or containing, elements of endodermal sinus tumour (yolk sac tumour) has been demonstrated, both in human tumours (Ballas, 1972;Tsuchida et al, 1973;Itoh et al, 1974;Talerman and Haije, 1974;N0rgaard-Petersen, Albrechtsen and Teilum, 1975) and in experimental tumours in mice (Hooghe et al, 1974). There have been only a few reports on the value of serum CEA determinations in patients with germ cell neoplasms (Reynoso et al, 1972;Wahren and Edsmyr, 1974).…”