Identifying Pain Subtypes in Patients With Craniofacial Lesions of Fibrous Dysplasia/McCune-Albright Syndrome.

BACKGROUND: Fibrous dysplasia/McCune-Albright syndrome (FD/MAS) is a genetic disorder, marked by bone lesions, often affecting the craniofacial skeleton. Pain is a prevalent yet heterogeneous symptom reported by patients with craniofacial FD. Effective treatments are currently lacking, posing a significant clinical challenge to patient care. PURPOSE: This preliminary study examined pain profiles in craniofacial FD and aimed to identify subtypes of patients based on pain phenotypes and emotional health. STUDY DESIGN, SETTING, SAMPLE: A prospective, cross-sectional study involving 15 patients with FD/MAS, conducted at Boston Children's Hospital and Massachusetts General Brigham's Hospitals. PREDICTOR/EXPOSURE/INDEPENDENT VARIABLE: Headache frequency, craniofacial pain severity, neuropathic pain quality, pain interference, allodynia, photophobia, depression, and anxiety were assessed using clinical questionnaires. MAIN OUTCOME VARIABLE(S): The primary outcome variable was the symptom profile derived from standardized clinical questionnaires and analyzed using principal component analysis and K-means clustering. COVARIATES: Covariates included demographic data, diagnosis, and lesion location(s). ANALYSES: Principal component analysis and K-means clustering of patient-reported measures of pain and emotional health were performed. Analysis of variance was conducted to determine significant differences among patient subtypes. Statistical significance was set at (P < .05). RESULTS: The study included 15 subjects with FD/MAS, with a mean age of 36.2 (13.9) years, including 1 male. Clustering analysis identified 3 subtypes of patients with distinct symptom profiles. Cluster 1 (n = 2) averaged 70 (28.3) headache days in a 90-day period, pain level of 7.5 (0.7) on a 0-10 scale, and severe anxiety, depression, allodynia, photophobia, and pain interference. Cluster 2 (n = 7) patients reported an average of 5.4 (7.5) headache days, an average pain level of 2.7 (2.6), mild or no anxiety, depression, allodynia, photophobia, and pain interference. Cluster 3 (n = 6) patients displayed a mixed symptom profile with an average of 47.3 (36.4) headache days and a pain level of 5.25 (1.4). Notably, patients with temporal and skull base lesions were predominantly found in Clusters 1 and 3, which exhibited the most severe symptomatology. CONCLUSIONS AND RELEVANCE: This study establishes a basis for future longitudinal research aimed at understanding underlying pain mechanisms and evaluating the response to personalized pain management strategies in subtypes of patients with craniofacial FD.