Identification of multiple cancer-associated myositis-specific autoantibodies in idiopathic inflammatory myopathies: a large longitudinal cohort study

Table 2 Risk of cancer within 3 years of myositis onset with different MSAs compared to the general population

Autoantibodies	Total^a	Observed^b	Expected^c	SIR (95% CI)
Anti-TIF1-γ	89	34	1.97	17.28 (11.94, 24.14)
Anti-NXP2	42	3	0.37	8.14 (1.63, 23.86)
Anti-SAE1	13	4	0.31	12.92 (3.23, 32.94)
Anti-Mi-2	24	0	0.53	0 (0, 7.03)
Anti-HMGCR	21	1	0.33	3.0 (0.30, 16.83)
Anti-SRP	30	0	0.32	0 (0, 11.47)
Anti-MDA5	92	0	1.25	0 (0, 2.97)
Anti-Jo-1	63	3	1.01	2.98 (0.60, 8.74)
Anti-PL-7	33	0	0.71	0 (0, 5.24)
Anti-PL-12	17	2	0.34	5.92 (0.59, 21.31)
Anti-EJ	22	0	0.40	0 (0, 9.36)
Anti-OJ	1	0	0.06	0 (0, 58.78)
MSAs-^d	170	11	2.76	3.99 (1.96, 7.14)

Abbreviations: SIR standardized incidence ratio, MSAs myositis specific autoantibodies
^aNumber of autoantibody-positive patients
^bObserved cancer cases within 3 years of myositis onset
^cExpected cancer cases based on estimates in the general population in China, after adjustment for age and gender
^dPatients who were negative for all of the MSAs listed

ISSN: 1478-6362