Cancer preceding giant cell arteritis: a case-control study.

OBJECTIVE

To study the association between previous cancer and giant cell arteritis (GCA).

METHODS

Using the resources of the Rochester Epidemiology Project, we identified incident cases of GCA diagnosed between January 1, 1950 and December 31, 2004. Each GCA patient was matched for age, sex, and length of medical history to 2 subjects without GCA from the same population. Medical records were reviewed. Diagnosis of cancer was confirmed by histopathologic analysis.

RESULTS

We identified 204 GCA cases and 407 controls. The GCA group included 163 women (80%) and 41 men (20%). Their mean +/- SD age was 76.0 +/- 8.2 years. The non-GCA group consisted of 325 women (80%) and 82 men (20%). Their mean +/- SD age was 75.6 +/- 8.4 years. At the index date, 45 GCA patients (22%) and 125 non-GCA patients (31%) had had a previous cancer. The odds ratio (OR) for previous cancer in cases compared with controls, adjusted for age, sex, and calendar year, was 0.63, and the 95% confidence interval (95% CI) was 0.42-0.94 (P = 0.022). The mean age at diagnosis of the first cancer before the index date was similar in the cases (67.5 +/- 11.9 years) and the controls (64.9 +/- 13.2 years) (P = 0.32). The mean +/- SD duration from the first cancer to the index date was 9.8 +/- 9.9 years in the cases and 11.7 +/- 10.8 years in the controls (P = 0.31). Cancer types were similar in both groups, but fewer gynecologic malignancies were noted in GCA patients (OR 0.39 [95% CI 0.13-1.15], P = 0.09). Colon cancer also appeared less commonly in the cases compared with the controls (OR 0.22 [95% CI 0.03-1.74], P = 0.15).

CONCLUSION

The findings of this population-based case-control study indicate that GCA patients had significantly fewer malignancies prior to the index date as compared with controls.