Stanford School of Medicine

Surgical Pathology Criteria

 use browser back button to return



  • Lung disease caused by inhaled mineral dust particles

Diagnostic Criteria

  • Some of the major types of pneumoconiosis are covered briefly here
    • For more complete coverage, see Biblilography at left
  • Coal workers pneumoconiosis (CWP)
    • Damage caused by inhaled carbon particles
    • Simple CWP
      • In its pure form, carbon is essentially non-fibrogenic
      • Dust macules
        • 0.5-6 mm collection of macrophages
        • Carbon particles are seen in both macrophages and free in the tissue
        • Principally located along bronchovascular bundles
        • No significant fibrosis
      • Foci of centrilobular emphysema
        • Forms adjacent to carbon particles
    • Complicated CWP
      • Occurs when mixed with silica and/or silicates resulting in fibrotic lesions
      • Mineral dust airway disease
        • Haphazard collagen with carbon free and in macrophages
      • Progressive massive fibrosis
        • Fibrotic nodule/mass ≥1 cm
        • May result from fused smaller nodules or diffuse fibrosis
      • Rheumatoid pneumoconiosis
        • Must have rheumatoid arthritis or Rh factor
        • Must have large cavitating nodules
          • Eosinophilic necrotic debris
          • Surrounded by fibroblasts, histiocytes, giant cells
  • Silicosis
    • Damage caused by inhalation of crystalline silica
    • Acute silicoproteinosis is very rare
      • Resembles pulmonary alveolar proteinosis
    • Chronic silicosis is characterized by fibrotic nodules
      • Sharply demarcated, hypocellular, hyalinized nodules
      • Lamellated collagen
      • Silica shows weakly birefringent needles
      • Nodules may fuse to produce progressive massive fibrosis
  • Mixed dust pneumoconiosis
    • Damage caused by inhalation of mixtures containg silica and silicates
      • Silica shows weakly birefringent needles
      • Silicates show strongly birefringent plates
    • Macules of interstitial macrophages
    • Mixed dust fibrotic lesions
      • Stellate lesions of macrophages and varying amounts of collagen
      • Has been termed "medusa head" because of extension into adjacent interstitium
    • Silicotic nodules
    • Progressive massive fibrosis
      • Fibrosis ≥1 cm
    • Forms a spectrum with CWP and silicosis
  • Silicatosis
    • Damage caused by inhalation of non-asbestos silicates
      • Includes talc, kaolin, mica, feldspars
      • Strongly birefringent plates
    • Findings similar to those of mixed dust pneumoconiosis
    • Granulomatous reaction may also be seen
    • Diffuse interstitial fibrosis may also be seen
      • May represent fused nodules
      • May resemble UIP
  • Asbestosis
    • Damage caused by inhaled asbestos fibers
    • Diffuse interstitial fibrosis, usually resembling usual interstitial pneumonia (UIP)
      • Fewer fibroblastic foci
      • Associated with pleural plaques
      • Asbestos bodies
        • Iron positive beads on a translucent core
        • Carbon and silicates may also ferruginate, but the core is different
      • Diagnosis requires ≥2 asbestos bodies per square cm and interstitial fibrosis
  • Berylliosis
    • T cell hypersensitivity reaction
    • Closely resembles sarcoidosis
      • Well formed granulomas with mild to moderate inflammation
      • Present along bronchovascular bundles
    • Diagnosed by history and T cell activation test
  • Hard metal disease (giant cell interstitial pneumonia)
    • Damage caused by inhaled cobalt, usually as hard metal dust
      • Birefringent black intracellular particles
    • Patchy filling of air spaces by macrophages and multinucleated giant cells
      • Giant cells frequently ingest macrophages
      • Multinucleated alveolar lining cells may be present
      • If giant cells are rare, resembles DIP
    • Foci of centrilobular fibrosis and interstitial inflammatory infiltrate
    • BOOP-like changes may be present

Gerald J Berry MD
Robert V Rouse MD
Department of Pathology
Stanford University School of Medicine
Stanford CA 94305-5342

Original posting/updates: 11/20/10

Classification / Lists

Idiopathic Interstitial Lung Diseases

Other Diffuse Parenchymal Lung Diseases



  • Travis WD, Colby TV, Koss MN, Rosado-de-Christenson ML, Müller NL, King TE Jr.  Non-neoplastic Disorders of the Lower Respiratory Tract, AFIP Atlas of Nontumor Pathology, First Series, Fascicle 2, 2002.
  • Khalil N, Churg A, Muller N, O'Connor R. Environmental, inhaled and ingested causes of pulmonary fibrosis. Toxicol Pathol. 2007;35(1):86-96.
  • Honma K, Abraham JL, Chiyotani K, De Vuyst P, Dumortier P, Gibbs AR, Green FH, Hosoda Y, Iwai K, Williams WJ, Kohyama N, Ostiguy G, Roggli VL, Shida H, Taguchi O, Vallyathan V. Proposed criteria for mixed-dust pneumoconiosis: definition, descriptions, and guidelines for pathologic diagnosis and clinical correlation. Hum Pathol. 2004 Dec;35(12):1515-23.
  • Roggli VL, Gibbs AR, Attanoos R, Churg A, Popper H, Cagle P, Corrin B, Franks TJ, Galateau-Salle F, Galvin J, Hasleton PS, Henderson DW, Honma K. Pathology of asbestosis- An update of the diagnostic criteria: Report of the asbestosis committee of the college of american pathologists and pulmonary pathology society. Arch Pathol Lab Med. 2010 Mar;134(3):462-80.
Printed from Surgical Pathology Criteria:
© 2009  Stanford University School of Medicine