• All IHC stains will include a positive control tissue

Ber EP4 can be useful in a panel of immunostains to differentiate between mesothelioma and adenocarcinoma

• The majority of lung and other adenocarcinomas are reactive with Ber EP4
• Mesotheliomas are usually negative for Ber EP4. However, 1-11% are reportedly positive for Ber EP4.
  • Only one report to date showed a relatively high rate of positivity (20%) for mesotheliomas with Ber EP4 (see Gaffey et al)
  • A staining pattern of CEA negative, Ber EP4 negative and LeuM1 (CD15) negative is said to be 100% specific for mesothelioma. (See Grove et al.)
  • A staining pattern of Ber EP4 positive, CEA positive and LeuM1 positive is said to be 96.8% specific for adenocarcinoma (See Grove et al)
  • Renal cell carcinoma and breast carcinomas are sometimes negative (25-50% of the time) for Ber EP4 or only very focally positive (see Gaffey et al, Sheibani et al)
  • False positives with Ber EP4 have been reported in cell block material (cytology) in peritoneal fluids from females (endosalpingiosis, endometriosis, and leiomyomata). (See Diaz-Arias et al).
• Reactivity with Ber EP4
  
  Normal Tissues:
  All human epithelial cells
  
  Tumors:
  
  

Submit a formalin-fixed, paraffin embedded tissue block

Formalin-fixed, paraffin embedded (FFPE) tissue block

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

• Ber EP4 is a cell surface glycoprotein present on most human epithelial cells
• Ber EP4 reacts with most epithelial tumors and is recognized as an epitope that is different from other epithelial antigens (i.e. keratins or CEA)

 Staining patterns

• Cell membrane and occasionally diffuse cytoplasmic

References

1. Gaffey et al. Am J Surg Pathol, 16(6):593-599, 1992.
2. Diaz-Arias et al. Diag Cytopath, 19(5):516-521, 1993.
3. Grove et al. Path Res and Prac, 1990:1044-1055, 1994.
4. Sheibani, et al. Am J Surg Pathol, 15(8):779-784, 1991.