Cancer and immune-mediated necrotizing myopathy: a longitudinal referral case-controlled outcomes evaluation.

Abstract

OBJECTIVES:

To investigate immune-mediated necrotizing myopathy (IMNM) association with cancer and its clinical implications.

METHODS:

IMNM cases were identified 1 January 2000 to 31 December 2020 matching sex and age controls (4:1).

RESULTS:

A total of 152 patients with IMNM were identified and among serologically tested, 60% (83/140) were HMGCR-IgG+, 14% (20/140) were SRP-IgG+ and 26% (37/140) were seronegative. Cancer rates were not significantly different between serological subgroups; 18.1% (15/83) HMGCR-IgG+, 25% (5/20) SRP-IgG+ and 30% (11/37) seronegative (P = 0.34). Cancer screening was performed within 12 months from IMNM diagnosis in 88% (134/152) (whole-body CT plus FDG-PET CT in 53, CT alone in 72 and FDG-PET alone in 9). FDG-PET/CT was positive in 73% (25/34) of cancers. Increasing age was the only risk associated with cancer (P = 0.02). The odds of developing cancer at ±3 or ±5 years from IMNM diagnosis was not higher than controls (OR = 0.49; CI: 0.325-0.76). Lifetime IMNM diagnosis of cancer was less compared with controls (OR = 0.5 CI: 0.33-0.78, P = 0.002). Most patients responded to treatment (137/147, P < 0.001). Death and treatment response did not significantly differ between cancer [23% (8/34); 88% (29/33)] and non-cancer patients [19% (23/118); 92% (108/118)]. In total, 13% (20/152) of patients died during follow-up compared with 14% (41/290) of medicine and 16% (46/290) of neurology controls (P = 0.8). Seropositives had greater life expectancy than seronegatives (P = 0.01).

CONCLUSIONS:

Greater cancer risk is not observed in IMNM vs controls. Cancer screening in IMNM should be individualized based on age-personal and family history, including consideration of FDG-PET/CT. Immune-treatment response did not differ with cancer.

• Authors: Shahar Shelly, Grayson Beecher, Margherita Milone, Teerin Liewluck, Floranne Ernste, James Triplett, Elie Naddaf, Anastasia Zekeridou, Andrew McKeon, Sean J Pittock, Divyanshu Dubey, John R Mills, Jay Mandrekar, Christopher J Klein
• Journal: Rheumatology (Oxford, England) (Rheumatology (Oxford)) Vol. 62 Issue 1 Pg. 281-289 (12 23 2022) ISSN: 1462-0332 [Electronic] England
• PMID: 35285492 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © The Author(s) 2022. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For permissions, please email: [email protected].

Chemical References

• Fluorodeoxyglucose F18
• Immunoglobulin G
• Autoantibodies

Topics

• Humans
• Muscle, Skeletal
• Fluorodeoxyglucose F18
• Positron Emission Tomography Computed Tomography
• Necrosis
• Myositis (diagnostic imaging, epidemiology)
• Autoimmune Diseases (complications, diagnostic imaging, epidemiology)
• Neoplasms (diagnostic imaging, epidemiology, complications)
• Immunoglobulin G
• Autoantibodies
• Muscular Diseases (diagnostic imaging, epidemiology, complications)