Characteristics of melanoma among patients with connective tissue disease: A retrospective study

Summary: Abstract Body: Pro-inflammatory conditions such as connective tissue disease (CTD) have been associated with an increased risk of malignancy, including melanoma. However, the impact of immunosuppression on cancer risk and tumor presentation remains unclear in this population. To further investigate melanoma characteristics among patients with a history of CTD, this single institution, retrospective study examined all patients with pre-existing CTD who were subsequently diagnosed with melanoma from 2013 to 2023. Our cohort included 151 patients, with 114 (75.5%) in the rheumatoid arthritis (RA) group and 37 (24.5%) in the non-RA group. Non-RA diagnoses included lupus, scleroderma, dermatomyositis, polymyositis, Sjogren syndrome, and mixed CTD. Of 151 patients, the majority were female (60.9%), White (96.7%), non-Hispanic (94.7%), and never-smokers (53.6%). The average time from CTD to melanoma diagnosis was 6 years. Just over half of the melanomas (52.7%) were invasive, mostly located on the head/neck (35.9%) and trunk (25.7%). Although mean Breslow depth was similar in RA and non-RA patients (1.7 ± 2.0 vs. 1.8 ± 2.7 mm), those with RA had more advanced tumor features such as >1 mitoses/hpf (58.3% vs. 38.9%), lymphovascular invasion (5.9% vs. 0.0%), and nodal metastasis (9.7% vs. 0.0%). The most commonly used immunosuppressive medications were high-dose prednisone (45.7%) and methotrexate (39.7%). These findings provide important insights into the clinicopathologic characteristics of melanoma in patients with CTD. Further research is needed to understand why RA patients may face more aggressive disease, including the roles of chronic inflammation and immunosuppressive medications. Future directions include identifying a matched cohort of immunocompetent patients to compare melanoma characteristics across groups. Sakshi Chopra¹, Khushnood Faraz¹, Kelly E. Owens¹, Rachel D'Cunha¹, Adaora Okeke¹, Kali Morrissette¹, Beiyu Liu², Cynthia L. Green², Anne Marano³, Michelle Pavlis^{3, 4} 1. Duke University School of Medicine, Durham, NC, United States. 2. Department of Biostatistics and Bioinformatics, Duke University School of Medicine, Durham, NC, United States. 3. Department of Dermatology, Duke University Health System, Durham, NC, United States. 4. Durham VA Health Care System, Durham, NC, United States. Pigmentation, Melanoma, and Melanoma Immune Surveillance