Cryptogenic organizing pneumonia: serial high-resolution CT findings in 22 patients

AJR Am J Roentgenol. 2010 Oct;195(4):916-22. doi: 10.2214/AJR.09.3940.


Objective: We conducted a review of serial high-resolution CT (HRCT) findings of cryptogenic organizing pneumonia (COP).

Materials and methods: Over the course of 14 years, we saw 32 patients with biopsy-confirmed COP. Serial HRCT scans were available for only 22 patients (seven men and 15 women; mean age, 52 years; median follow-up period, 8 months; range, 5-135 months). Serial CT scans were evaluated by two chest radiologists who reached a conclusion by consensus. Overall changes in disease extent were classified as cured, improved (i.e., ≥ 10% decrease in extent), not changed, or progressed (i.e., ≥ 10% increase in extent). When there were remaining abnormalities, the final follow-up CT images were analyzed to express observers' ideas regarding what type of interstitial lung disease the images most likely suggested.

Results: The two most common patterns of lung abnormality on initial scans were ground-glass opacification (86% of patients [19/22]) and consolidation (77% of patients [17/22]), distributed along the bronchovascular bundles or subpleural lungs in 13 patients (59%). In six patients (27%), the disease disappeared completely; in 15 patients (68%), the disease was decreased in extent; and in one patient (5%), no change in extent was detected on follow-up CT. When lesions remained, the final follow-up CT findings were reminiscent of fibrotic nonspecific interstitial pneumonia in 10 of 16 patients (63%).

Conclusion: Although COP is a disease with a generally good prognosis, most patients (73%) with COP have some remaining disease seen on follow-up CT scans, and, in such cases, the lesions generally resemble a fibrotic nonspecific interstitial pneumonia pattern.

MeSH terms

  • Cryptogenic Organizing Pneumonia / diagnostic imaging*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Retrospective Studies
  • Tomography, X-Ray Computed* / methods