Multiple Sclerosis and Lung Cancer: A Single Cancer Center Experience in Philadelphia.

Background: The association between multiple sclerosis (MS) and lung cancer (LC) remains poorly understood. This retrospective, single center study aims to characterize the clinical features and outcomes of LC in patients with MS, shedding light on this unique patient cohort characterized by immune dysregulation and significant immunosuppressive therapy.

Methods: This retrospective study analyzed 38 MS patients diagnosed with LC at Sidney Kimmel Comprehensive Cancer Center at Jefferson in Philadelphia, PA between January 1, 2016 and July 1, 2023. Clinical data including patient demographics, MS treatments, cancer diagnosis details (date, stage, histology), molecular and fusion data, PD-L1 status, and survival data were recorded and analyzed.

Results: In our cohort of 38 patients, 27 patients were female. Twenty nine patients identified as White and 6 as Black. About 33 patients had NSCLC (24 adenocarcinoma, 6 squamous cell carcinoma, 1 large cell lung cancer, 1 mucoepidermoid tumor, and 1 carcinoid tumor), 3 had SCLC, and 1 had unknown pathology. Nine patients received steroids and 15 received biologic therapy for the treatment of MS. The median time between MS and LC diagnosis was 16.3 years. The average age at LC diagnosis was 68.2 ± 9.8 years. Among the 38 patients, 19 patients were diagnosed with stage I disease, 2 were diagnosed with stage II, 1 was diagnosed with stage III, and 16 were diagnosed with stage IV diseases. Among 15 patients with molecular testing, BRAF mutation was found in 1 patient, EGFR mutation in 4 patients, and KRAS mutation in 2 patients. 1 patient out of 14 tested demonstrated an ALK fusion. PD-L1 testing was recorded in 12 patients: 3 had 0%, 6 had 1% to 49%, and 3 had > 50% PD-L1 expression. The average overall survival was 2.4 years (95% CI: 1.4-8.1 years).

Conclusions: Patients with MS were significantly exposed to immunosuppressive therapies, which may impact immune surveillance and the development of LC. In this cohort, MS patients with LC exhibited targetable mutations and PD-L1 expression. However, the use of immunotherapy in LC with concurrent MS remains limited. Nearly half of the patients had stage I LC and demonstrated favorable overall survival. Our findings highlight the need for further investigation into the relationship between MS and LC.