The authors of a new study published in the Annals of Rheumatic Diseases say malignancy should no longer be a major consideration in clinical decisions on the treatment of systemic necrotising vasculitis (SNV).
The study pooled data on malignancies from five randomised controlled trials (n=733) in SNV conducted by the French Vasculitis Study Group.
During the observation period of 4485.9 person-years (PY), 39 (5.3%) patients developed malignancies (869.5/100,000 PY), including solid cancers in 34 (4.6%) cases (757.9/100,000 PY) and haematological malignancies in 5 (0.7%; 111.5/100,000 PY).
The median time to malignancy’s diagnosis was 4.1 (interquartile range, 1.4-8.1) years.
The calculated standardised incidence ratios (SIR) for all cancers showed no difference between this cohort and the general population described in the French National registry (SIR, 0.95; 95% CI, 0.68-1.30; P=.84).
Solid cancers included gastrointestinal cancers in nine (26.5%) patients, urogenital cancers in eight (23.5%) patients, non-melanoma skin cancers (NMSC) in seven (20.6%) patients, lung cancers in six (17.6%) patients, breast cancers in two (5.9%) patients and brain tumour and carcinoma of unknown primary origin in one patient each.
Haematological malignancies included myelodysplastic syndromes in two patients and multiple myeloma, myeloproliferative syndrome and kidney lymphoma in one patient each.
In multivariate analysis, age ≥65 years (HR, 2.38; 95% CI, 1.13-4.99; P=.022), the use of azathioprine (HR, 3.05; 95% CI, 1.10-0.42; P=.032) and methotrexate (HR, 3.24; 95% CI, 1.07-9.81; P=.038) as maintenance were independently associated with the occurrence of malignancy. Similar results were obtained after exclusion of NMSC.
“Taken together, these findings suggest that malignancy should no longer be considered as a predominant feature driving the therapeutic strategy,” the authors concluded.
