Benign and Malignant Tumor Burden in Patients with Systemic Sclerosis: A Retrospective Single-Center Study from the United Arab Emirates.

INTRODUCTION: Malignancy is a significant comorbidity for patients with systemic scle-rosis (SSc). Data regarding the prevalence and risks of developing malignancy in SSc, particular-ly in the United Arab Emirates (UAE) population, are scarce. This study aims to investigate the proportion of benign and malignant tumors in the UAE's SSc patients. MATERIALS AND METHODS: SSc patients from the UAE Scleroderma Registry from April 2015 to April 2023 were characterized according to the presence of a tumor, whether benign or malig-nant. Descriptive statistics were utilized to examine the study's variables. RESULTS: Out of 133 patients, 33 (25%) had a history of a tumor. Benign and malignant tumors were reported in 54.5% and 42.4% of the cohort, respectively. The remaining 3.1% were tumors of unknown nature. Among the 133 patients, seven (21%) had genitourinary tumors, followed by 5 (15%) head and neck tumors, and 4 (12%) gastrointestinal tumors. The mean age of SSc diag-nosis was 38.9 ± 13.7 years. Among patients with tumors, there was SSc autoantibody positivity with topoisomerase I (Scl-70) (36%), anticentromere (ACA) (27%), and anti-polymerase III (ARA) (6%, p < 0.00001). IF-ANA was positive in 88% of patients with a predominantly centromere pattern (p < 0.05) and elevated titers ranging between 1:640 and 1:1280 (p < 0.05). Tumors were diagnosed a mean of 3.2 years before SSc diagnosis in some patients and a mean of 11 years after SSc diagnosis in others. DISCUSSION: Our findings reveal a distinctive malignancy profile characterized by a higher preva-lence of genitourinary, head, and neck, and gastrointestinal tumors compared to international co-horts, and an earlier average age of tumor onset highlighting unique regional characteristics. CONCLUSION: The study is the first to describe tumor burden in the UAE's SSc population and highlights the need to tailor malignancy screening and management.