Background: Fibrous dysplasia/McCune-Albright syndrome (FD/MAS) may cause pain, impaired ambulation and decreased quality of life (QoL). International guidelines advocate management of FD/MAS in a... Show moreBackground: Fibrous dysplasia/McCune-Albright syndrome (FD/MAS) may cause pain, impaired ambulation and decreased quality of life (QoL). International guidelines advocate management of FD/MAS in a tertiary multidisciplinary care pathway, but no longitudinal data are available to support this recommendation. This multicenter prospective observational study aimed to evaluate effects of 1 year of treatment in the FD/MAS care pathway in 2 tertiary clinics on QoL and pain, assessed by change in Short Form 36 and Brief Pain Inventory between baseline and follow-up. Patients completing baseline questionnaires < 1 year after intake were classified as new referrals, others as under chronic care. Results: 92 patients were included, 61 females (66%). 22 patients (24%) had monostotic disease, 16 (17%) isolated craniofacial FD, 27 (40%) polyostotic FD and 17 (19%) MAS. 26 were new referrals (28%) and 66 chronic patients (72%). Median age at baseline was 47 years (Q1-Q3 36-56). Skeletal burden correlated with baseline Physical Function (r(s) = - 0.281, p = 0.007). QoL was in all domains lower compared to the general population. New referrals reported clinically important differences (CID) over time in domains Physical Function (mean 67 & PLUSMN; SD24 to 74 & PLUSMN; 21, effect size (ES) 0.31, p = 0.020), Role Physical (39 & PLUSMN; 41 to 53 & PLUSMN; 43, ES 0.35, p = 0.066), Social Functioning (64 & PLUSMN; 24 to 76 & PLUSMN; 23, ES 0.49, p = 0.054), and Health Change (39 & PLUSMN; 19 to 53 & PLUSMN; 24, ES 0.76, p = 0.016), chronic patients in Physical Function (52 & PLUSMN; 46 to 66 & PLUSMN; 43, ES 0.31, p = 0.023) and Emotional Wellbeing (54 & PLUSMN; 27 to 70 & PLUSMN; 15, ES 0.59, p < 0.001). New referrals reported a CID of 1 point in maximum pain, average pain and pain interference, chronic patients reported stable scores. Change in pain interference and Role Physical were correlated (r(s) = - 0.472, p < 0.001). Patients with limited disease extent improved more than patients with severe disease. Patients receiving FD-related therapy had lower baseline scores than patients not receiving therapy and reported improvements in QoL after 1 year. Yet also patients without FD-related therapy improved in Physical Function. Conclusions: All FD-subtypes may induce pain and reduced QoL. A multidisciplinary care pathway for FD/MAS may improve pain and QoL, mainly in new referrals without MAS comorbidities with low baseline scores. Therefore, we recommend referral of patients with all subtypes of FD/MAS to specialized academic centers. Show less
Fibrous dysplasia is a heterogeneous rare bone disorder that is caused by the mosaic distribution of a postzygotic mutation of the GNAS-gene. Although its predominant features are the... Show moreFibrous dysplasia is a heterogeneous rare bone disorder that is caused by the mosaic distribution of a postzygotic mutation of the GNAS-gene. Although its predominant features are the characteristic bony lesions, there is a wide spectrum of FD phenotypes that include a continuously expanding list of extraskeletal manifestations. In line with its wide range of phenotypes, FD is associated with a wide clinical spectrum of symptoms, with pain, deformity, and fractures, leading not only to decreased mobility and function but also significantly impairing Quality of Life. Available surgical and medical therapeutic options should be delivered in a patient-tailored, individualized manner, with full knowledge of their limitations and complications to ensure their most optimal outcome of the various modalities used, singly or in combination. FD is often a multisystemic disease, particularly its most severe forms, so that a multidisciplinary approach is mandatory to achieve the best life-long outcomes. The rarity of FD dictates that all health care professionals involved in the care of FD should invest in international collaboration to provide the necessary power of numbers to address the unanswered questions posed by this ubiquitous disorder, and fulfil the clinical unmet need of developing best clinical practice guidelines for its management. Show less
