Differences Between Mesothelioma and Adenocarcinoma

 

 

Uploaded: 2007-08-18,  Updated: 2007-08-18

 

 

Mesothelioma

Adenocarcinoma

Radiology Findings

Diffuse nodular pleural thickening Diffuse nodular pleural masses
Often unilateral Often bilateral
Nodular thickening of fissures Intra-parenchymal lung nodules
Encasement, invasion of bone, decreased lung volume Encasement unusual, but can occur
Can metastasize Often associated with hilar adenopathy

Gross Features

 

Yellow fluid, can be bloody

Variable, may be bloody

Viscous to gelatinous Less thick or gelatinous

Patterns

Continuum, morphologic kinship Foreign cells or groups
Larger, more complex  groups, cell-in-cell, long chains Less complex, smooth community borders
More irregular knobby, flower, papillary outlines Glandular, acinar patterns
Often collagen cores Rare collagen core

Cells

Larger and more pleomorphic than benign cells Columnar
Relatively constant N/C ratio Increased N/C ratio
Common multinucleated giant cells Rare multinucleated giant cells

Border

Often windows, blebs, lacy skirts (microvilli) Unusual windows or microvilli

Cytoplasm

Denser center, paler and lacy edge Delicate, homogenous, pale to foamy
Two tone staining Uniform staining

Vacuoles

   
Location Perinuclear Periphery Eccentric or random
Size/Shape Small, uniform Small, slightly variable Large, marked variation or irregular

Content

Lipid

Glycogen

Secretory epithelial mucin

  Rare degenerative or mesenchymal mucin (HA) vacuoles May form large balloon or signet ring vacuoles

Nucleus

   
Location

Central or paracentral

Often eccentric
Shape Often less pleomorphic, not bizarre, binucleation Often pleomorphic, occasionally bizarre
Chromatin Less hyperchromatic More hyperchromatic
Nuclear Membrane Thick, irregular Thick, irregular
Nucleoli Enlarged, multiple or macro-nucleoli Prominent

Background

 

Combined epithelial and spindle cells Not common
Epithelial mucin not present Epithelial mucin often present

Special Stains

   
PAS, undigested (+), abundant, peripheral, finely May be (+), droplet, diffuse
PAS, digested Usually (-) Often (+)
Mucicarmine Usually (-) Often (+)
Alcian Blue Usually (+), but (-) after hyaluronidae digestion Often (+) and remains (+) after hyaluronidae digestion
Oil Red O Fine, centrally located in most cases Large, eccentric in 10% cases

Electron Microscopy

   
True Glands No Yes
Intermediate Filaments Abundant, peri-nuclear Sparse
Microvilli Long, slender, bushy and branching Short, blunt, stubby rootlets and terminal web
Glycogen Prominent Unusual
Epithelial Mucin Not present Common

Immunostaining

   
CEA (-) (+)
Keratins (+)HMW and LMW (+) LMW
Vimentin (+) (-)
EMA (+) (+)
CD15/Leu-M1 (-) (+)
Secretory Component (-) (+)
Calretinin (+) (-)

 

Reference

 
  • The art and science of cytopathology. Richard M Demay, MD. 1996

  Summarized by Zenggang Pan, MD, PhD