Overview

After a biopsy, tissue samples are sent to a pathologist who examines them under a microscope. Special staining techniques called immunohistochemistry help distinguish mesothelioma from other cancers and identify the specific cell type.

Why This Matters

Accurate pathological diagnosis is critical because it determines treatment options and prognosis. Mesothelioma can be difficult to distinguish from other cancers, making expert pathological review essential.

Procedures and Tests

Microscopic Examination

Initial review of tissue structure and cell appearance under standard microscopy.

First step in analysis

Immunohistochemistry (IHC)

Uses antibodies to detect specific proteins that help identify cell types. Key markers include calretinin, WT1, and D2-40.

Essential for diagnosis

Histochemical Staining

Special stains highlight specific cellular features and structures.

Supports diagnosis

Electron Microscopy

High-magnification imaging to see detailed cell structures. Less commonly used today.

Used in difficult cases

Molecular Testing

Analyzes genetic markers like BAP1 loss, which is common in mesothelioma and helps confirm diagnosis.

Increasingly important

What to Expect

  • Pathology results typically take 1-2 weeks
  • Report includes cell type and grade
  • May recommend additional testing
  • Second opinion often advised for complex cases

Advantages

  • Provides definitive diagnosis
  • Identifies cell type (critical for treatment)
  • Distinguishes from other cancers
  • Molecular testing can guide targeted therapy

Limitations

  • Requires adequate tissue sample
  • Can be challenging to distinguish from other cancers
  • Expert pathologist review recommended
  • Some rare subtypes may be missed

Next Steps After Diagnosis

Once mesothelioma is confirmed, your medical team will work to determine the stage of the disease and develop a treatment plan. This typically involves:

  • Additional imaging to assess cancer spread
  • Consultation with mesothelioma specialists
  • Discussion of treatment options based on cell type and stage
  • Consideration of clinical trial eligibility
Learn about staging → Explore treatment options →