Incidence of malignancy in Takayasu arteritis in Korea.

Cancer is associated with autoimmune diseases. This study aimed to estimate the incidence of cancer in a cohort of patients with Takayasu arteritis (TA) and to compare this incidence with the general population cancer rate in South Korea in a retrospective cohort study. The medical records of TA patients who underwent medical care at our institution between 1979 and 2009 were reviewed. The 2008 National Cancer Registry was used as the reference to calculate the standardized incidence ratio (SIR). The mean age of 180 patients was 48.6 ± 14.3 years, and 87.2 % of the patients were female. During the follow-up of 2,285 person years, 10 females developed cancer. Breast cancer was the most common malignancy with three cases, followed by two endometrial, one gastric, one colon, one pancreatic, one myelodysplastic syndrome (MDS) with refractory anemia with excess blasts, and one multiple myeloma. The SIR of cancer in TA was comparable with that of the general population at 1.3 [95 % confidence interval (CI) 0.6-2.3]; however, the risk of MDS was significantly increased (SIR 51.3; 95 % CI 1.3-285.7). While two patients with hematologic malignancies died, all TA patients with non-hematologic malignancies were still alive during the follow-up period. The overall risk of malignancy is not increased in TA. Further work is needed to determine if TA is associated with an increased risk of certain hematologic malignancies.