Systemic phenotype of sarcoidosis associated with radiological stages. Analysis of 1230 patients

Background: To analyze the association between Scadding radiological stages of sarcoidosis at diagnosis and the disease phenotype (epidemiology, clinical presentation and extrathoracic involvement) in one of the largest cohorts of patients with sarcoidosis reported from southern Europe. Methods: The SARCOGEAS-Study Group includes a multicenter database of consecutive patients diagnosed with sarcoidosis according to the WASOG 1999 criteria. Extrathoracic disease at diagnosis was defined according to the 2014 instrument and the clusters proposed by Schupp et al. Results: We analyzed 1230 patients (712 female, mean age 47 yrs.) who showed the following Scadding radiologic stages at diagnosis: stage 0 (n = 98), stage I (n = 395), stage II (n = 500), stage III (n = 195) and stage IV (n = 42). Women were overrepresented in patients presenting with extrathoracic/extrapulmonary disease, while the diagnosis was made at younger ages in patients presenting with BHL, and at older ages in those presenting with pulmonary fibrosis (q values < 0.05). Multivariable adjusted analysis showed that patients presenting with pulmonary involvement (especially those with stages II and III) had a lower frequency of concomitant systemic involvement in some specific extrathoracic clusters (cutaneous-adenopathic/musculoskeletal, ENT and neuroocular/OCCC) but a higher frequency for others (hepatosplenic), in comparison with patients with extrapulmonary involvement (stages 0 and I). The presence of either BHL or fibrotic lesions did not influence the systemic phenotype of patients with pulmonary involvement. Conclusions: The key determinant associated with a differentiated systemic phenotype of sarcoidosis at diagnosis was interstitial pulmonary involvement rather than the individual Scadding radiological stage.