Table 4.
Observed and expected numbers of cancers diagnosed within 2 years preceding and 3 years following diagnosis of idiopathic inflammatory myopathy, with standardized incidence ratio (SIR).
| Diagnosis | Gender | Observed | Expected | SIR (95% CI) | p, 2-tailed |
|---|---|---|---|---|---|
| DM | Female | 16 | 2.15 | 7.44 (4.25, 12.09) | < 0.0001 |
| DM | Male | 8 | 1.01 | 7.89 (3.41, 15.55) | < 0.0001 |
| PM | Female | 0 | 1.77 | 0 (0, 2.09) | 0.34 |
| PM | Male | 3 | 1.64 | 1.82 (0.38, 5.33) | 0.46 |
| ADM | Female | 2 | 0.72 | 2.76 (0.33, 9.98) | 0.33 |
| ADM | Male | 1 | 0.24 | 4.19 (0.11, 23.35) | 0.42 |
| IBM | Female | 1 | 0.22 | 4.46 (0.11, 24.88) | 0.40 |
| IBM | Male | 0 | 0.72 | 0 (0, 5.09) | 0.97 |
| JDM | Female | 0 | 0.01 | 0 (0, 446.8) | 1.00 |
| JDM | Male | 0 | 0.01 | 0 (0, 685.02) | 1.00 |
| MCTD | Female | 1 | 0.56 | 1.79 (0.05, 9.97) | 0.86 |
| MCTD | Male | 0 | 0.13 | 0 (0, 27.81) | 1.00 |
| All | Female | 20 | 5.43 | 3.68 (2.25, 5.68) | < 0.0001 |
| All | Male | 12 | 3.76 | 3.19 (1.65, 5.58) | < 0.01 |
DM: dermatomyositis; PM: polymyositis; ADM: amyopathic DM; IBM: inclusion body myositis; JDM: juvenile DM; MCTD: myositis associated with connective tissue disease; All: summed data for all IIM diagnoses.