Expression of human chorionic gonadotropin beta in gastric carcinoma: A retrospective immunohistochemical study.

CONTEXT

Beta Human Chorionic Gonadotropin (βHCG), a marker of the trophoblastic neoplasm, is also secreted by non-trophoblastic neoplasms including gastric carcinomas. Its role in disease progression remains unclear.

AIM

To investigate the incidence of βHCG positivity in gastric carcinomas and correlate its presence with the biological behavior of the tumor.

SETTING AND DESIGN

A hospital-based, immunohistochemical study.

MATERIALS AND METHODS

One hundred and fifty formalin-fixed, paraffin-embedded tissue specimens from histopathologically confirmed cases of gastric carcinoma were immunostained using an indigenously developed antibody against βHCG. Tumors with diffuse reactivity to βHCG were considered as positive. Those with occasional, focal or no reactivity to βHCG were considered as negative.

STATISTICAL ANALYSIS

Differences in βHCG staining were compared according to the histological grade and surgical stage using the χ(2) test. Using the Cox proportional hazards model, the time till the onset of development of an adverse outcome after surgery (defined as death, local or distant metastasis) was compared between the bHCG positive and negative tumors.

RESULTS

Twenty-eight (18.7%) of the 150 specimens were βHCG positive. No association was found between the histological grade (P=0.49) and the surgical stage (P=0.19) with βHCG positivity. The median disease-free survival after surgery was not different among βHCG positive and negative tumors. Risk of an adverse outcome after surgery was significantly associated with the stage of the tumor (Hazard ratio=2.9, 95% confidence interval: 1.1-7.4). No association was observed with grade or βHCG positivity.

CONCLUSION

βHCG immunoreactivity was observed in about one-fifth of the gastric cancers. βHCG reactivity, however, played no role in the biological behavior.