• All IHC stains will include a positive control tissue

• Gestational trophoblastic tumors (hydatiform moles and gestational choriocarcinomas) stain positively for HCG
• Choriocarcinomas almost always stain positively for HCG
• Syncytiotrophoblastic giant cells, when present in seminomas, embryonal carcinomas, endodermal sinus tumors and teratomas may stain positively for HCG
• HCG positivity has also been reported in hepatoblastomas of childhood and carcinomas of the breast (up to 50% in some series), lung, gastrointestinal tract, ovary, uterus, and salivary glands
• Bladder tumors may occasionally produce HCG (especially if they are of urachal origin)

Submit a formalin-fixed, paraffin-embedded tissue

Formalin-fixed, paraffin-embedded (FFPE) tissue block

FFPE tissue section mounted on a charged, unstained slide

Ambient (preferred)

• Unlabeled/mislabeled block
• Insufficient tissue
• Slides broken beyond repair

Immunohistochemical staining and microscopic examination

If requested, an interpretive report will be provided

Specifications

• Human chorionic gonadotropin (HCG) is a glycoprotein MWt 40,000) consisting of a protein core and a carbohydrate side chain. It is secreted in large quantities by the placenta, normally circulating at readily detectable levels only during gestation. Immunohistochemical studies reveal localization of HCG in syncytiotrophoblasts. (Occasionally, some mononuclear cytotrophoblasts show weak positivity for HCG. Although this may be the result of antigen leakage from adjacent syncytiotrophoblasts, one cannot exclude the possibility that HCG may also be elaborated by cytotrophoblasts.) A wide variety of tumors secrete HCG, however serum levels do not necessarily correlate with histologically demonstrable HCG

Staining patterns

• Cytoplasmic based staining