Mesothelioma Diagnosis Biopsy and Pathology 2

Question 1

Which stain is used on routine pathology sections to first evaluate suspected mesothelioma?

Accepted Answer

Hematoxylin and eosin (H&E)

Answer

H&E staining is the standard first-line histological stain used to assess tumor morphology and cell type in all biopsy specimens.

Question 2

Which IHC marker is typically negative in mesothelioma but positive in metastatic breast carcinoma to the pleura?

Accepted Answer

GATA3

Answer

GATA3 is expressed in breast and urothelial carcinoma but is absent in mesothelioma, making it useful in distinguishing pleural metastases from primary mesothelioma.

Question 3

D2-40 (podoplanin) IHC staining in mesothelioma primarily highlights which feature?

Accepted Answer

Lymphatic differentiation and mesothelial cells

Answer

D2-40 stains lymphatic endothelium and mesothelial cells, and its expression supports a mesothelial origin in pleural biopsies.

Question 4

FISH (fluorescence in situ hybridization) for CDKN2A (p16) deletion is used in mesothelioma pathology to:

Accepted Answer

Distinguish malignant mesothelioma from benign mesothelial hyperplasia

Answer

Homozygous deletion of CDKN2A detected by FISH is a reliable molecular marker of malignancy in mesothelioma, distinguishing it from benign reactive proliferations.

Question 5

In sarcomatoid mesothelioma, which IHC marker is most reliably positive?

Accepted Answer

Pancytokeratin

Answer

Pancytokeratin (AE1/AE3) staining is the most consistently positive marker in sarcomatoid mesothelioma, as calretinin and WT1 are often lost in this subtype.

Mesothelioma Diagnosis Practice Test

Mesothelioma Diagnosis Practice Test

Mesothelioma Diagnosis Biopsy and Pathology 2