Research Article

Risk of Malignant Neoplasm in Patients with Incident Rheumatoid Arthritis 1980–2007 in relation to a Comparator Cohort: A Population-Based Study

Table 1

Cumulative incidence rates of malignancy in 813 patients with rheumatoid arthritis in 1980–2007 compared to 813 subjects without rheumatoid arthritis.

Malignancy site/typeNumber of events after incidence/index in RA/non-RACumulative incidence at 10 years for RA patients (± SE)Cumulative incidence at 10 years for non-RA subjects (± SE)Hazard ratio (95% CI)

Any malignancy excluding NMSC143/11811.8 ± 1.29.3 ± 1.11.32 (1.03, 1.68)
Any malignancy including NMSC194/17915.6 ± 1.414.3 ± 1.41.13 (0.92, 1.38)
Any solid malignancy116/11310.3 ± 1.18.8 ± 1.11.11 (0.85, 1.44)
Hematologic28/91.5 ± 0.40.6 ± 0.33.58 (1.69, 7.60)
Head/neck11/90.9 ± 0.30.9 ± 0.31.41 (0.58, 3.42)
Colon/rectal9/90.8 ± 0.30.8 ± 0.31.08 (0.43, 2.72)
Lung29/172.1 ± 0.51.1 ± 0.41.97 (1.08, 3.59)
Breast (among females)24/291.8 ± 0.63.5 ± 0.80.95 (0.55, 1.63)
Bladder4/100.4 ± 0.20.6 ± 0.30.46 (0.14, 1.49)
Melanoma11/131.2 ± 0.40.8 ± 0.30.90 (0.40, 2.00)

NMSC86/1096.3 ± 0.97.5 ± 1.00.83 (0.63, 1.10)
Basal cell carcinoma57/753.3 ± 0.75.0 ± 0.70.81 (0.57, 1.14)
Squamous cell carcinoma56/694.2 ± 0.74.3 ± 0.70.90 (0.63, 1.29)

NMSC = nonmelanoma skin cancer; RA = rheumatoid arthritis; SE = standard error; CI = confidence interval.
No malignancies were observed in these sites/types: multiple myeloma, myeloproliferative syndrome, and myelodysplastic syndrome. Comparisons were not performed for the following sites/types with fewer than 5 malignancies per cohort (number of events after incidence in RA/index in non-RA): gastric (1/3), pancreatic (4/2), other digestive (2/5), other thorax (1/0), bone (1/0), soft tissue (1/4), ductal carcinoma in situ (6/4), ovary (2/1), other gynecological (4/4), kidney (2/5), other genitourinary (2/2), ophthalmologic (1/0), central nervous system (2/3), and other (2/2).
Adjusted for age, sex, and calendar year of RA incidence/index date. Cumulative incidence is adjusted for the competing risk of death.