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Published on: March 17, 2015
Ber-EP4 staining in effusion cytology: A potential source of false positives
Cristina Díaz Del Arco1, Melchor Saiz-Pardo Sanz1, Luis Ortega Medina1
1Department of Surgical Pathology, Hospital Clínico San Carlos, Madrid, Spain.
Insights
Ber-EP4 antibody aids in diagnosing metastatic carcinoma but can also stain mesothelium in effusions, potentially causing misdiagnosis. Pathologists must interpret Ber-EP4 results cautiously alongside other tests.
Area of Science:
- Cytopathology
- Oncology
- Immunohistochemistry
Background:
- Distinguishing reactive mesothelium from carcinoma in serous effusions is diagnostically challenging.
- Immunocytochemistry (ICC) is crucial for improving accuracy in body fluid cytology.
- Ber-EP4 antibody is recognized for its high sensitivity and specificity in detecting metastatic carcinoma.
Purpose of the Study:
- To investigate the occurrence and pattern of Ber-EP4 positivity in mesothelial cells within effusion cytology specimens.
- To highlight the potential for Ber-EP4 staining in mesothelium to lead to misdiagnosis.
- To review existing literature on Ber-EP4 staining in effusion cytology.
Main Methods:
- Review of published articles on Ber-EP4 staining in effusion cytology.
- Analysis of cytological specimens with Ber-EP4 positivity in mesothelial cells.
- Correlation of ICC findings with clinical data and other diagnostic markers.
Main Results:
- Ber-EP4 positivity has been observed in mesothelial cells in some cytological specimens.
- Reported cases often show weak or focal (less than 50% of cells) Ber-EP4 staining in mesothelium.
- Some instances exhibit strong Ber-EP4 positivity in both cytology and histology.
Conclusions:
- Ber-EP4 positivity in mesothelium is a potential pitfall in effusion cytology, necessitating careful interpretation.
- Pathologists and clinicians must be aware of this diagnostic challenge.
- ICC results for Ber-EP4 should be cautiously interpreted and correlated with clinical history and other markers.
Abstract:
The distinction between reactive mesothelium and carcinoma in serous effusions can be very difficult. Immunocytochemistry (ICC) is the most widely used tool to improve the diagnostic accuracy of body fluid cytology, with several ICC markers being proposed. Ber-EP4 antibody has shown high sensitivity and specificity rates for diagnosing metastatic carcinoma. In our department, we have detected Ber-EP4 positivity in mesothelium in some cytological specimens. We reviewed all articles on Ber-EP4 staining in effusion cytology, summarized current findings and analyzed the staining pattern of all cases expressing Ber-EP4. Some cases showing Ber-EP4 positivity in mesothelium have been reported, most of which showed only weak Ber-EP4 staining or staining of less than 50% of mesothelial cells. However, some cases may show strong positivity both in cytological and histological specimens. Clinicians and pathologists should be aware of this source of misdiagnosis, and ICC results in mesothelium should be always interpreted cautiously and correlated with clinical tests, other ICC markers and patient's previous history.
