Original contributionCicatricial variant of cryptogenic organizing pneumonia

- A distinct form of cryptogenic organizing pneumonia is described.
- Cicatricial organizing pneumonia is often radiographically persistent as bilateral nodules in middle-aged patients.
- Within a region of scar, architecture is preserved, whereas airspaces contain dense collagen.
- Cicatricial organizing pneumonia is not steroid responsive.
- Differential diagnosis with nonspecific interstitial pneumonia, fibrosing type.

SummaryThis study of 12 patients focused on a variant of cryptogenic organizing pneumonia (COP) labeled the cicatricial form in which the airspaces of the lung are filled with and consolidated by dense collagenized scar tissue associated with preservation of underlying lung architecture. Patients were predominantly middle-aged men and presented with bilateral lung disease in the majority of cases, often with nodular or reticulonodular disease (10/12; 83%). Patients were usually symptomatic with shortness of breath, cough, and dyspnea on exertion. Fifty-five percent of patients (6/11) had persistent or progressive disease at follow-up (mean, 68.5 months; median, 110 months). The cicatricial variant of cryptogenic organizing pneumonia may be predictive of a more recalcitrant form of COP that needs to be morphologically separated from classical COP, usual interstitial pneumonia, and nonspecific interstitial pneumonia.