title: Primary choriocarcinoma and human chorionic gonadotrophin-producing giant cell carcinoma of the lung: are they independent entities?
abstract: OBJECTIVE
  Human chorionic gonadotrophin (hCG) is a useful marker for chorionic proliferative disorders, such as choriocarcinoma. Although hCG synthesis in lung cancers is frequent, primary pulmonary choriocarcinoma (PCC) is rare. To clarify the differences between primary choriocarcinoma and hCG-producing giant cell carcinoma (GCC) of the lung, we compared the clinicopathological and immunohistochemical findings of these tumours.
  
  
  RESULTS
  Three patients, one with PCC and two with hCG-producing GCC, were included in this study. They were all middle-aged men and habitual smokers. The growth of these tumours and the progression of the clinical courses were extremely rapid, and the patients all died within 8 months after the pulmonary tumours were found. Haemorrhagic appearance was a common macroscopic feature of the specimens obtained. Microscopically, both types of tumours mainly consisted of atypical polygonal cells. While PCC contained many syncytial trophoblast-like multinucleated cells that had strong immunoreactivity for anti-hCG, such cells were relatively few in hCG-producing GCC. These histological and immunohistochemical findings reflected the serum test result for hCG, which was higher in the case of PCC.
  
  
  CONCLUSIONS
  There are a few differences between PCC and hCG-producing GCC, as described above. Reliable distinction between them seems to be difficult for pathologists and worthless for clinicians.
authors.affiliation: Department of Pathology, Osaka City General Hospital; Department of Pathology, Osaka City University Medical School, Osaka, Japan. ikura@med.osaka-u.ac.jp
authors.forename: Y
authors.initials: Y
authors.lastname: Ikura
authors.forename: T
authors.initials: T
authors.lastname: Inoue
authors.forename: H
authors.initials: H
authors.lastname: Tsukuda
authors.forename: T
authors.initials: T
authors.lastname: Yamamoto
authors.forename: M
authors.initials: M
authors.lastname: Ueda
authors.forename: Y
authors.initials: Y
authors.lastname: Kobayashi
mesh_terms: D002272:Carcinoembryonic Antigen / Q000378:metabolism; D018286:Carcinoma, Giant Cell / Q000097:blood / Q000473:pathology*; D002822:Choriocarcinoma / Q000097:blood / Q000473:pathology*; D006063:Chorionic Gonadotropin / Q000097:blood; D003937:Diagnosis, Differential; D006801:Humans; D007124:Immunoenzyme Techniques; D008175:Lung Neoplasms / Q000097:blood / Q000473:pathology*; D008297:Male; D008875:Middle Aged
chemical_list: D002272:Carcinoembryonic Antigen; D006063:Chorionic Gonadotropin