COMBINED CHORIOCARCINOMA AND YOLK-SAC TUMOR ARISING IN BARRETTS-ESOPHAGUS

A patient with primary adenocarcinoma with yolk sac and trophoblastic differentiation occurring in Barrett's esophagus is reported. Yolk sac differentiation at this site has not been described previously. The d iagnosis of germ cell differentiation initially was suggested by the f inding of elevated serum tumor marker levels. The patient experienced disease remission after cytotoxic chemotherapy. Germ cell differentiat ion may be difficult to identify in small biopsy samples, which may no t be representative of the tumor as a whole. The finding of germ cell differentiation defines therapy and predicates for a relatively good p rognosis, which is in contrast to adenocarcinoma. Because of the signi ficance of germ cell differentiation in the selection of appropriate t herapy, immunostaining for germ cell tumor markers is suggested in all patients with adenocarcinoma who are younger than 50 years.