Distinction of an epithelial malignant mesothelioma from an adenocarcinoma of the lung may be difficult on routine histologic examination. Carella et al studied panels of immunohistochemical stains for the ability to distinguish between these two tumors. The authors are from Bologna and Bolzano in Italy.
Antibody |
Criteria for a Positive Reaction |
calretinin |
cytoplasmic granular staining in > 2% of cells, with nuclei negative |
cytokeratin 5/6 |
diffuse cytoplasmic staining with perinuclear enhancement |
Ber-EP4 |
lateral staining in > 2% of cells |
CEA |
cytoplasmic staining in > 2% |
Antibody |
Mesothelioma |
Adenocarcinoma of the Lung |
Adenosquamous Carcinoma Lung |
calretinin |
87% positive |
10% positive |
usually negative |
cytokeratin 5/6 |
87% positive |
0% positive |
usually positive |
Ber-EP4 |
7% positive |
100% positive |
usually positive |
CEA |
4% focal positive or < 2% positive |
85% positive |
usually positive |
Panels (cytokeratin 5/6 and Ber-EP4 common to all 3): each 98.48% correctly classified:
(1) calretinin, cytokeratin 5/6, Ber-EP4, and CEA (4): global likelihood ratio test 78.2
(2) calretinin, cytokeratin 5/6, and Ber-EP4 (3): global likelihood ratio test 77.15
(3) cytokeratin 5/6, Ber-EP4, and CEA (3): global likelihood ratio test 69.66
Expected Result |
Panel 1 |
4 of 4 |
yes |
3 of 4 |
probable |
2 of 4 |
possible |
1 of 4 |
unlikely |
0 of 4 |
no |
Expected Result |
Panel 2 and 3 |
3 of 3 |
yes |
2 of 3 |
probable |
1 of 3 |
possible |
0 of 3 |
no |
Specialty: Hematology Oncology, Surgery, general, Pulmonology